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- 1. phys. stat. sol. (b) 245, 1298-1314 (2008) , “EPR identification of intrinsic defects in SiC”, J. Isoya, T. Umeda, N. Mizuochi, N. T. Son, E. Janzen, T. OhshimaThe structure determination of intrinsic defects in 4H-SiC, 6H-SiC, and 3C-SiC by means of EPR is based on measuring the angular dependence of the 29Si/13C hyperfine (HF) satellite lines, from which spin densities, sp-hybrid ratio, and p-orbital direction can be determined over... (Read more)Si SiC diamond| EPR Theory electron-irradiation thermal-meas./anneal-exp.| +1 -1 0(neutral) 1.0eV~ 13C 29Si C1h C3v Carbon Csi D2d EI5/6 HEI1 HEI9/10 P6/7 Silicon T1 Td Tv2a V1/2/3 Vc Vsi antisite dangling-bond mono(=1) motional-effect n-type p-type pair(=2) quartet semi-insulating spin-relaxation triplet vacancy .inp files: SiC/Baranov/Baranov_g.inp SiC/EI5_C1h/5.inp SiC/EI5_C3v/5.inp SiC/EI6_RT/6.inp SiC/HEI10/HEI10a.inp SiC/HEI10/HEI10b.inp SiC/HEI1_C1h/1.inp SiC/HEI9/HEI9a.inp SiC/HEI9/HEI9b.inp SiC/SI5_C1h/4.inp SiC/Ky2/Ky2.inp SiC/Tv2a/Main.INP SiC/Vsi-_II_4H/Main.INP SiC/Vsi-_II_6H/Main.INP SiC/Vsi-_I_4H/Main.INP SiC/Vsi-_I_6H/Main.INP | last update: Takahide Umeda
- 2. Appl. Phys. Lett. 90, 072502 (2007) , “Effect of oxygen vacancies on spin-dependent tunneling in Fe/MgO/Fe magnetic tunnel junctions”, J. P. Velev, K. D. Belashchenko, S. S. Jaswal, and E. Y. TsymbalFirst-principles calculations based on density functional theory are used to elucidate the effect of O vacancies, forming F centers, on spin-dependent tunneling in Fe/MgO/Fe(001) magnetic tunnel junctions. O vacancies produce occupied localized s states and unoccupied resonant p... (Read more)
- 3. J. Appl. Phys. 102, 013530 (2007) , “Fluorine-vacancy complexes in Si-SiGe-Si structures”, D. A. Abdulmalik, P. G. Coleman, H. A. W. El Mubarek, and P. AshburnFluorine-vacancy (FV) complexes have been directly observed in the Si0.94Ge0.06 layer in a Si-SiGe-Si structure, using variable-energy positron annihilation spectroscopy (VEPAS). These complexes are linked to the significant reduction of boron diffusion in the SiGe layer via... (Read more)
- 4. J. Appl. Phys. 101, 023515 (2007) , “He induced nanovoids for point-defect engineering in B-implanted crystalline Si”, E. Bruno, S. Mirabella, F. Priolo, E. Napolitani, C. Bongiorno, and V. RaineriIn this paper we present a systematic study on the formation of He ion implantation induced nanovoids in Si and how they influence the self-interstitial (Is) supersaturation, thus affecting the diffusion and electrical activation of implanted boron in crystalline silicon. We implanted He ions... (Read more)
- 5. Phys. Rev. B 75, 245202 (2007) , “Identification of positively charged carbon antisite-vacancy pairs in 4H-SiC”, T. Umeda, J. Ishoya, T. Ohshima, N. Morishita, H. Itoh, and A. GaliAn antisite-vacancy pair and a monovacancy are a set of fundamental stable and/or metastable defects in compound semiconductors. Theory predicted that carbon antisite-vacancy pairs would be much more stable in p-type SiC than silicon vacancies and that they would be a common defect. However,... (Read more)
- 6. Phys. Rev. B 75, 195208 (2007) , “Supercell and cluster density functional calculations of the thermal stability of the divacancy in germanium”, C. Janke, R. Jones, S. Öberg, and P. R. BriddonLarge vacancy clusters, or voids, formed during crystal growth have been reported in Ge. The divacancy is a precursor to such clusters, and is believed to be stable up to 150 or 180 °C. It is also believed to form in Ge irradiated at room temperature where single vacancies are mobile. Density... (Read more)
- 7. Phys. Rev. B 75, 193409 (2007) , “Magnetic properties of vacancies in a graphitic boron nitride sheet by first-principles pseudopotential calculations”, M. S. Si and D. S. XueWe use ab initio methods to calculate the magnetic properties of vacancies in a graphitic boron nitride sheet (g-BN). By applying a full spin-polarized description to the system, we demonstrate that the nitrogen vacancy (VN) or the boron vacancy (VB)... (Read more)
- 8. Phys. Rev. B 75, 193201 (2007) , “Compensating point defects in 4He+-irradiated InN”, F. Tuomisto, A. Pelli, K. M. Yu, W. Walukiewicz, and W. J. SchaffWe use positron annihilation spectroscopy to study 2 MeV 4He+-irradiated InN grown by molecular-beam epitaxy and GaN grown by metal-organic chemical-vapor deposition. In GaN, the Ga vacancies act as important compensating centers in the irradiated material, introduced at a... (Read more)
- 9. Phys. Rev. B 75, 144404 (2007) , “Ferromagnetism in Fe-doped ZnO nanocrystals: Experiment and theory”, Debjani Karmakar, S. K. Mandal, R. M. Kadam, P. L. Paulose, A. K. Rajarajan, T. K. Nath, A. K. Das, I. Dasgupta, and G. P. DasFe-doped ZnO nanocrystals are successfully synthesized and structurally characterized by using x-ray diffraction and transmission electron microscopy. Magnetization measurements on the same system reveal a ferromagnetic to paramagnetic transition temperature above 450 K with a low-temperature... (Read more)
- 10. Phys. Rev. B 75, 144103 (2007) , “Multiscale modeling of point defects in Si-Ge(001) quantum wells”, B. Yang and V. K. TewaryA computationally efficient hybrid Green's function (GF) technique is developed for multiscale modeling of point defects in a trilayer lattice system that links seamlessly the length scales from lattice (subnanometers) to continuum (bulk). The model accounts for the discrete structure of the lattice... (Read more)
- 11. Phys. Rev. B 75, 144102 (2007) , “Theoretical investigation of nitrogen substitution in cubic zirconia”, Thomas BredowNitrogen substitution of oxygen ions in cubic zirconia was studied theoretically at density functional level. Nitrogen contents of 12.5 and 3.1% were studied with Zr8O16−mN2 and Zr32O64−mN2 supercells. For... (Read more)
- 12. Phys. Rev. B 75, 134106 (2007) , “Exact linear response of reacting thermal defects driven by creation processes”, C. P. FlynnThe exact, linear response at steady state is calculated for reacting, but otherwise noninteracting, thermal defects driven by defect creation processes. The theory applies to vacancies and interstitials in the bulk, or to adatoms and advacancies on surface terraces. A wide variety of possible... (Read more)
- 13. Phys. Rev. B 75, 115418 (2007) , “Early stages of radiation damage in graphite and carbon nanostructures: A first-principles molecular dynamics study”, Oleg V. Yazyev, Ivano Tavernelli, Ursula Rothlisberger, and Lothar HelmUnderstanding radiation-induced defect formation in carbon materials is crucial for nuclear technology and for the manufacturing of nanostructures with desired properties. Using first-principles molecular dynamics, we perform a systematic study of the nonequilibrium processes of radiation damage in... (Read more)
- 14. Phys. Rev. B 75, 115206 (2007) , “Local-density-functional calculations of the vacancy-oxygen center in Ge”, A. Carvalho, R. Jones, J. Coutinho, V. J. B. Torres, S. Öberg, J. M. Campanera Alsina, M. Shaw, and P. R. BriddonWe carry out a comprehensive density-functional study of the vacancy-oxygen (VO) center in germanium using large H-terminated Ge clusters. The importance of a nonlinear core correction to account for the involvement of the 3d electrons in Ge-O bonds is discussed. We calculate the electrical... (Read more)
- 15. Phys. Rev. B 75, 115205 (2007) , “Stability of I3 complexes in III-V compound semiconductors by tight-binding molecular dynamics”, G. Zollo and F. GalaIntrinsic interstitials in GaAs are known to have a large formation energy that makes their concentration almost negligible in as-grown materials. However, interstitials must be explicitly considered in implanted GaAs where collision cascades, induced by the energetic ions, produce a large amount of... (Read more)
- 16. Phys. Rev. B 75, 085208 (2007) , “Clustering of vacancy defects in high-purity semi-insulating SiC”, R. Aavikko, K. Saarinen, F. Tuomisto, B. Magnusson, N. T. Son, and E. JanzénPositron lifetime spectroscopy was used to study native vacancy defects in semi-insulating silicon carbide. The material is shown to contain (i) vacancy clusters consisting of four to five missing atoms and (ii) Si-vacancy-related negatively charged defects. The total open volume bound to the... (Read more)
- 17. Phys. Rev. B 75, 045211 (2007) , “Ab initio supercell calculations on aluminum-related defects in SiC”, A. Gali, T. Hornos, N. T. Son, E. Janzén, and W. J. ChoykeAb initio supercell calculations of the binding energies predict complex formation between aluminum and carbon interstitials in SiC. In high-energy implanted SiC aluminum acceptor can form very stable complexes with two carbon interstitials. We also show that carbon vacancy can be attached to... (Read more)
- 18. Phys. Rev. B 75, 045210 (2007) , “Positron trapping kinetics in thermally generated vacancy donor complexes in highly As-doped silicon”, K. Kuitunen, K. Saarinen, and F. TuomistoWe have measured positron lifetime and Doppler broadening in highly As-doped silicon containing thermally generated V-As3 defect complexes (vacancy is surrounded by three arsenic atoms). We observe positron detrapping from the V-As3 defect complex and determine... (Read more)
- 19. Phys. Rev. B 75, 035211 (2007) , “Self- and foreign-atom diffusion in semiconductor isotope heterostructures. II. Experimental results for silicon”, H. Bracht, H. H. Silvestri, I. D. Sharp, and E. E. HallerWe report the diffusion of boron, arsenic, and phosphorus in silicon isotope multilayer structures at temperatures between 850 °C and 1100 °C. The diffusion of all dopants and self-atoms at a given temperature is modeled with the same setting of all native-point-defect-related parameters.... (Read more)
- 20. Phys. Rev. B 75, 014111 (2007) , “Effects of vacancies on the properties of disordered ferroelectrics: A first-principles study”, L. Bellaiche, Jorge Íñiguez, Eric Cockayne, and B. P. BurtonA first-principles-based model is developed to investigate the influence of lead vacancies on the properties of the disordered Pb(Sc1/2Nb1/2)O3 (PSN) ferroelectric. Lead vacancies generate large, inhomogeneous, electric fields that reduce barriers between energy... (Read more)
- 21. Phys. Rev. B 75, 014102 (2007) , “First-principles study of vacancy formation in hydroxyapatite”, Katsuyuki Matsunaga and Akihide KuwabaraFirst-principles plane-wave calculations were performed for hydroxyapatite (HAp) in order to investigate the electronic structure and vacancy formation mechanisms. The HAp unit cell contains PO4 tetrahedra and OH groups formed by covalent P-O and H-O bonds. Ca ions play a role for... (Read more)
- 22. Phys. Rev. Lett. 98, 265502 (2007) , “Monovacancy and Interstitial Migration in Ion-Implanted Silicon”, P. G. Coleman and C. P. BurrowsThe migration of monovacancies (V0) and self-interstitials (I) has been observed in ion-implanted low-doped float-zone silicon by variable-energy positron annihilation spectroscopy. V0 and I were created by the in situ implantation of ~20 keV... (Read more)
- 23. Phys. Rev. Lett. 98, 216803 (2007) , “High Mobility in LaAlO3/SrTiO3 Heterostructures: Origin, Dimensionality, and Perspectives”, G. Herranz, M. Basletić, M. Bibes, C. Carrétéro, E. Tafra, E. Jacquet, K. Bouzehouane, C. Deranlot, A. Hamzić, J.-M. Broto, A. Barthélémy, and A. FertWe have investigated the dimensionality and origin of the magnetotransport properties of LaAlO3 films epitaxially grown on TiO2-terminated SrTiO3(001) substrates. High-mobility conduction is observed at low deposition oxygen pressures... (Read more)
- 24. Phys. Rev. Lett. 98, 196802 (2007) , “Origin of Charge Density at LaAlO3 on SrTiO3 Heterointerfaces: Possibility of Intrinsic Doping”, Wolter Siemons, Gertjan Koster, Hideki Yamamoto, Walter A. Harrison, Gerald Lucovsky, Theodore H. Geballe, Dave H. A. Blank, and Malcolm R. BeasleyAs discovered by Ohtomo and Hwang, a large sheet charge density with high mobility exists at the interface between SrTiO3 and LaAlO3. Based on transport, spectroscopic, and oxygen-annealing experiments, we conclude that extrinsic defects in the form of oxygen vacancies... (Read more)
- 25. Phys. Rev. Lett. 98, 185501 (2007) , “Enhanced Ductile Behavior of Tensile-Elongated Individual Double-Walled and Triple-Walled Carbon Nanotubes at High Temperatures”, J. Y. Huang, S. Chen, Z. F. Ren, Z. Wang, K. Kempa, M. J. Naughton, G. Chen, and M. S. DresselhausWe report exceptional ductile behavior in individual double-walled and triple-walled carbon nanotubes at temperatures above 2000 °C, with tensile elongation of 190% and diameter reduction of 90%, during in situ tensile-loading experiments conducted inside a high-resolution transmission... (Read more)
- 26. Phys. Rev. Lett. 98, 146403 (2007) , “Evidence for an Oxygen Diffusion Model for the Electric Pulse Induced Resistance Change Effect in Transition-Metal Oxides”, Y. B. Nian, J. Strozier, N. J. Wu, X. Chen, and A. IgnatievElectric-pulse induced resistance hysteresis switching loops for Pr0.7Ca0.3MnO3 perovskite oxide films were found to exhibit an additional sharp “shuttle tail” peak around the negative pulse maximum for films deposited in an oxygen-deficient ambient. The... (Read more)
- 27. Phys. Rev. Lett. 98, 115503 (2007) , “Oxygen Vacancy Clustering and Electron Localization in Oxygen-Deficient SrTiO3: LDA+U Study”, Do Duc Cuong, Bora Lee, Kyeong Mi Choi, Hyo-Shin Ahn, Seungwu Han, and Jaichan LeeWe find, using a local density approximation +Hubbard U method, that oxygen vacancies tend to cluster in a linear way in SrTiO3, a prototypical perovskite oxide, accompanied by strong electron localization at the 3d state of the nearby Ti transition metal ion. The vacancy... (Read more)
- 28. Phys. Rev. Lett. 98, 095901 (2007) , “Experimental Evidence of the Vacancy-Mediated Silicon Self-Diffusion in Single-Crystalline Silicon”, Yasuo Shimizu, Masashi Uematsu, and Kohei M. ItohWe have determined silicon self-diffusivity at temperatures 735–875 °C based on the Raman shift of longitudinal optical phonon frequencies of diffusion annealed 28Si/30Si isotope superlattices. The activation enthalpy of 3.6 eV is obtained in such low temperature... (Read more)
- 29. Phys. Rev. Lett. 98, 045501 (2007) , “Dopability, Intrinsic Conductivity, and Nonstoichiometry of Transparent Conducting Oxides”, Stephan Lany and Alex ZungerExisting defect models for In2O3 and ZnO are inconclusive about the origin of conductivity, nonstoichiometry, and coloration. We apply systematic corrections to first-principles calculated formation energies ΔH, and validate our theoretical defect model against... (Read more)
- 30. Appl. Phys. Lett. 89, 262904 (2006) , “Oxygen vacancy in monoclinic HfO2: A consistent interpretation of trap assisted conduction, direct electron injection, and optical absorption experiments”, Peter Broqvist and Alfredo PasquarelloThe authors calculate energy levels associated with the oxygen vacancy in monoclinic HfO2 using a hybrid density functional which accurately reproduces the experimental band gap. The most stable charge states are obtained for varying Fermi level in the HfO2 band gap. To compare... (Read more)
- 31. Appl. Phys. Lett. 89, 262112 (2006) , “Identification of oxygen and zinc vacancy optical signals in ZnO”, T. Moe Børseth, B. G. Svensson, A. Yu. Kuznetsov, P. Klason, Q. X. Zhao, and M. WillanderPhotoluminescence spectroscopy has been used to study single crystalline ZnO samples systematically annealed in inert, Zn-rich and O-rich atmospheres. A striking correlation is observed between the choice of annealing ambient and the position of the deep band emission (DBE) often detected in ZnO. In... (Read more)
- 32. Appl. Phys. Lett. 89, 202904 (2006) , “Effects of O vacancies and C doping on dielectric properties of ZrO2: A first-principles study”, Gargi Dutta, K. P. S. S. Hembram, G. Mohan Rao, and Umesh V. WaghmareThe authors determine electronic properties, structural stability, and dielectric response of zirconia (ZrO2) with oxygen vacancies (O vacancies) and carbon doping (C doping) using first-principles density functional theory calculations based on pseudopotentials and a plane wave basis.... (Read more)
- 33. Appl. Phys. Lett. 89, 191903 (2006) , “Vacancy self-trapping during rapid thermal annealing of silicon wafers”, Thomas A. Frewen and Talid SinnoThe density and spatial distribution of oxide precipitates within a crystalline silicon wafer is of paramount importance for microelectronic device yield. In this letter, the authors show how the formation of previously unconsidered, very small vacancy aggregates can explain macroscopic spatial... (Read more)
- 34. Appl. Phys. Lett. 89, 172906 (2006) , “Oxygen vacancy motion in Er-doped barium strontium titanate thin films”, Junling Wang and Susan Trolier-McKinstryAmphoteric dopants are widely used in BaTiO3-based dielectrics to improve capacitor reliability. In this work, an analogous approach was explored for barium strontium titanate thin films. Ba0.7Sr0.3TiO3 thin films were prepared by chemical solution... (Read more)
- 35. Appl. Phys. Lett. 89, 152904 (2006) , “First principles calculations of oxygen vacancy passivation by fluorine in hafnium oxide”, Wei Chen, Qing-Qing Sun, Shi-Jin Ding, David Wei Zhang, and Li-Kang WangThe fluorine incorporation into HfO2 with oxygen vacancies has been investigated using first principles calculations. The authors show that atomic fluorine can efficiently passivate the neutral oxygen vacancy with excess energies of 4.98 and 4.39 eV for threefold- and... (Read more)
- 36. Appl. Phys. Lett. 89, 142914 (2006) , “Defect passivation in HfO2 gate oxide by fluorine”, K. Tse and J. RobertsonThe authors have calculated that fluorine substituting for oxygen gives no gap states in HfO2. This accounts for the good passivation of oxygen vacancies by F seen experimentally. Bonding arguments are used to account for why F may be the most effective passivant in ionic oxides such as... (Read more)
- 37. Appl. Phys. Lett. 89, 092113 (2006) , “Large fluorine-vacancy clusters in Si and their capture efficiency for self-interstitials”, Giorgia M. Lopez and Vincenzo FiorentiniBased on ab initio density-functional energetics for saturated (n=2m+2) fluorine-vacancy clusters FnVm for m up to 4, the authors set up a model showing that (a) fluorine-vacancy (FV) aggregates in Si can form in any... (Read more)
- 38. Appl. Phys. Lett. 89, 082908 (2006) , “Negative oxygen vacancies in HfO2 as charge traps in high-k stacks”, J. L. Gavartin, D. Muñoz Ramo, A. L. Shluger, G. Bersuker, and B. H. LeeThe optical excitation and thermal ionization energies of oxygen vacancies in m-HfO2 are calculated using a non-local density functional theory with atomic basis sets and periodic supercell. The thermal ionization energies of negatively charged V and... (Read more)
- 39. Appl. Phys. Lett. 89, 082510 (2006) , “Observation and manipulation of paramagnetic oxygen vacancies in Co-doped TiO2 nanocrystals”, Dengyu Pan, Guoliang Xu, Liya Lv, Yuan Yong, Xiuwei Wang, Jianguo Wan, Guanghou Wang, and Yunxia SuiElectron paramagnetic resonance measurements were presented to investigate paramagnetic oxygen vacancies (F+ centers) in Co-doped TiO2 nanocrystals. Surface and interior F+ centers were manipulated by washing or/and annealing. Anisotropic surface... (Read more)
- 40. Appl. Phys. Lett. 89, 071916 (2006) , “Migration and redistribution of oxygen vacancy in barium titanate ceramics”, L. Chen, X. M. Xiong, H. Meng, P. Lv, and J. X. ZhangDegradation of barium titanate based multilayer capacitor mainly results from migration and redistribution of oxygen vacancy. For barium titanate ceramics, the authors observe an internal friction relaxation peak around 70 °C due to oxygen vacancy, and its relaxation strength differs greatly... (Read more)
- 41. Appl. Phys. Lett. 89, 061903 (2006) , “Nitrogen related vacancies in GaAs based quantum well superlattices”, J. Slotte, K. Saarinen, E.-M. Pavelescu, T. Hakkarainen, and M. PessaThe authors report on the influence of nitrogen incorporation on vacancies in GaAs based superlattices. The samples were molecular beam epitaxy grown on p-type GaAs substrates with the superlattice structure consisting of ten periods of quantum well material separated by GaAs buffers. Three... (Read more)
- 42. Appl. Phys. Lett. 89, 053511 (2006) , “Density functional theory study of deep traps in silicon nitride memories”, Max Petersen and Yakov RoizinUsing density functional theory, the interaction of hydrogen with a nitrogen vacancy in -Si3N4 is investigated. A single H atom was found to be energetically favorable over non- and doubly protonated vacancies. The traps composed of excess silicon and hydrogen have negative... (Read more)
- 43. Appl. Phys. Lett. 89, 042503 (2006) , “Evidence for magnetism due to oxygen vacancies in Fe-doped HfO2 thin films”, Nguyen Hoa Hong, Nathalie Poirot, and Joe SakaiFe-doped HfO2 thin films are room temperature ferromagnetic. In comparison with results of the undoped HfO2 films, it seems that the Fe doping is not the main cause for the ferromagnetism but only acts as a catalyst. Experimental results of oxygen annealing and vacuum heat... (Read more)
- 44. Appl. Phys. Lett. 88, 253504 (2006) , “Single silicon vacancy-oxygen complex defect and variable retention time phenomenon in dynamic random access memories”, T. Umeda, K. Okonogi, K. Ohyu, S. Tsukada, K. Hamada, S. Fujieda, and Y. MochizukiThe variable retention time phenomenon has recently been highlighted as an important issue in dynamic random access memory (DRAM) technology. Based on electrically detected magnetic resonance and simulation studies, we suggest that a single Si vacancy-oxygen complex defect is responsible for this... (Read more)
- 45. Appl. Phys. Lett. 88, 242508 (2006) , “Thermal limits on field alignment of nanoparticle FePt media”, J. A. Bain, W. F. Egelhoff, Jr.We derive a simple expression for the average angular orientation distribution of ferromagnetic FePt particles in an applied field in thermal equilibrium. This system is closely related to the Langevin expression for paramagnetic susceptibility, which computes the average orientation of particles in... (Read more)
- 46. Appl. Phys. Lett. 88, 201918 (2006) , “Diffusion of zinc vacancies and interstitials in zinc oxide”, Paul Erhart and Karsten AlbeThe self-diffusion coefficient of zinc in ZnO is derived as a function of the chemical potential and Fermi level from first-principles calculations. Density functional calculations in combination with the climbing image-nudged elastic band method are used in order to determine migration barriers for... (Read more)
- 47. Appl. Phys. Lett. 88, 193502 (2006) , “Role of oxygen vacancy in HfO2/SiHfO2/Si(100) interfaces”, D.-Y. Cho, S.-J. Oh, Y. J. Chang, T. W. Noh, R. Jung, J.-C. LeeWe have investigated the interface states in HfO2/SiO2/Si(100) systems that were prepared by using the in situ pulsed laser deposition technique. X-ray photoelectron spectroscopy data revealed that when the HfO2 film thickness exceeds 11 Å, the film... (Read more)
- 48. Appl. Phys. Lett. 88, 182903 (2006) , “Effects of Al addition on the native defects in hafnia”, Q. Li, K. M. Koo, W. M. Lau, P. F. Lee, J. Y. Dai, Z. F. Hou, X. G. GongTwo occupied native defect bands are experimentally detected in pure HfO2. The density of states of band one in the middle of the band gap reduces drastically with the Al addition, while that of band two slightly above the valence-band maximum remains rather unaffected. We attribute the... (Read more)
- 49. Appl. Phys. Lett. 88, 162107 (2006) , “Physical origin of threshold voltage problems in polycrystalline silicon/HfO2 gate stacks”, Dae Yeon Kim, Joongoo Kang, and K. J. ChangBased on theoretical calculations, we find that at p+ polycrystalline silicon (poly-Si)/HfO2 gates, Si interstitials are easily migrated from the electrode, forming HfSi bonds with a charge transfer to the electrode, and the resulting interface dipole raises the Fermi level... (Read more)
- 50. Appl. Phys. Lett. 88, 091919 (2006) , “Calculation of deep carrier traps in a divacancy in germanium crystals”, J. Coutinho, V. J. B. Torres, R. Jones, A. Carvalho, S. berg, P. R. BriddonWe present an ab initio density functional study on the electronic structure and electrical properties of divacancies in Ge. Although suffering essentially different Jahn-Teller distortions when compared to the analogous defect in Si, the relative location of the electrical levels in the gap... (Read more)
- 51. Appl. Phys. Lett. 88, 091912 (2006) , “Hydrogen-vacancy related defect in chemical vapor deposition homoepitaxial diamond films studied by electron paramagnetic resonance and cathodoluminescence”, N. Mizuochi, H. Watanabe, H. Okushi, S. Yamasaki, J. Niitsuma, T. SekiguchiHydrogen-vacancy related defect (H1) in chemical vapor deposition homoepitaxial diamond films has been investigated by electron paramagnetic resonance and cathodoluminescence. It is found that the concentration of H1 significantly decreases as the dilution... (Read more)
- 52. J. Appl. Phys. 100, 113725 (2006) , “Light- and bias-induced metastabilities in Cu(In,Ga)Se2 based solar cells caused by the (VSe-VCu) vacancy complex”, Stephan Lany and Alex ZungerWe investigate theoretically light- and bias-induced metastabilities in Cu(In,Ga)Se2 (CIGS) based solar cells, suggesting the Se–Cu divacancy complex (VSe-VCu) as the source of this hitherto puzzling phenomena. Due to its amphoteric nature, the... (Read more)
- 53. J. Appl. Phys. 100, 113519 (2006) , “Void growth during thermal decomposition of silicon oxide layers studied by low-energy electron microscopy”, H. Hibino, M. Uematsu, and Y. WatanabeLow-energy electron microscopy (LEEM) has been used to investigate void growth during thermal decomposition of 1–2-nm-thick silicon oxide on Si substrates. Real-time LEEM observations clarify that the void size (square root of the void area) grows linearly with time. The temperature dependence... (Read more)
- 54. J. Appl. Phys. 100, 113513 (2006) , “Theoretical study of nitrogen-doping effects on void formation processes in silicon crystal growth”, Hiroyuki Kageshima, Akihito Taguchi, and Kazumi WadaNitrogen-doping effects in silicon crystal growth have been theoretically studied using thermodynamical simulation based on first-principles calculation results. The results show that the densities of various complexes are determined in the balance between the enthalpy effects and the entropy... (Read more)
- 55. J. Appl. Phys. 100, 083521 (2006) , “Thermally activated charge reversibility of gallium vacancies in GaAs”, Fedwa El-Mellouhi, Norm, and MousseauThe dominant charge state for the Ga vacancy in GaAs has been the subject of a long debate, with experiments suggesting −1, −2, or −3 as the best answer. We revisit this problem using ab initio calculations to compute the effects of temperature on the Gibbs free energy of... (Read more)
- 56. J. Appl. Phys. 100, 073501 (2006) , “Identification by photoluminescence and positron annihilation of vacancy and interstitial intrinsic defects in ion-implanted silicon”, R. Harding, G. Davies, J. Tan, P. G. Coleman, C. P. Burrows, and J. Wong-LeungDefect centers generated in crystalline silicon by MeV Si implants have been investigated by a combination of photoluminescence, variable-energy positron annihilation measurements, depth profiling by etching, annealing studies, and the dependence on impurities. The broad 935 meV photoluminescence... (Read more)
- 57. J. Appl. Phys. 100, 064501 (2006) , “Introduction of defects into HfO2 gate dielectrics by metal-gate deposition studied using x-ray photoelectron spectroscopy and positron annihilation”, A. Uedono, T. Naito, T. Otsuka, K. Shiraishi, K. Yamabe, S. Miyazaki, H. Watanabe, N. Umezawa, T. Chikyow, Y. Akasaka, S. Kamiyama, Y. Nara, and K. YamadaThe impact of TiN deposition on thin HfO2 films formed on Si substrates was studied using x-ray photoelectron spectroscopy and a monoenergetic positron beam. For the predeposition sample, the positrons implanted into Si were found to diffuse toward the HfO2/Si interface under... (Read more)
- 58. J. Appl. Phys. 100, 034509 (2006) , “Vacancy-impurity complexes in polycrystalline Si used as gate electrodes of HfSiON-based metal-oxide-semiconductors probed using monoenergetic positron beams”, A. Uedono, K. Ikeuchi, T. Otsuka, K. Yamabe, K. Eguchi, M. Takayanagi, S. Ishibashi, T. Ohdaira, M. Muramatsu, and R. SuzukiVacancy-impurity complexes in polycrystalline Si (poly-Si) used as a gate electrode of the metal-oxide-semiconductor field-effect transistor (MOSFET) were probed using monoenergetic positron beams. Doppler broadening spectra of the annihilation radiation and the positron lifetimes were measured for... (Read more)
- 59. J. Appl. Phys. 99, 113506 (2006) , “Theoretical properties of the N vacancy in p-type GaN(Mg,H) at elevated temperatures”, S. M. Myers, A. F. Wright, M. Sanati, and S. K. EstreicherThe elevated-temperature properties of the N vacancy in Mg-doped, p-type GaN containing H were modeled using atomic-configuration energies and phonon densities of states obtained with density-functional theory. This study encompassed both equilibrium thermodynamics and the rates of diffusion... (Read more)
- 60. J. Appl. Phys. 99, 066105 (2006) , “Thermal stability of in-grown vacancy defects in GaN grown by hydride vapor phase epitaxy”, F. Tuomisto, K. Saarinen, T. Paskova, B. Monemar, M. Bockowski, and T. SuskiWe have used positron annihilation spectroscopy to study the thermal behavior of different native vacancy defects typical of freestanding GaN grown by hydride vapor phase epitaxy under high pressure annealing at different annealing temperatures. The results show that the... (Read more)
- 61. J. Appl. Phys. 99, 053516 (2006) , “Correlation between Zn vacancies and photoluminescence emission in ZnO films”, A. Zubiaga, J. A. García, F. Plazaola, F. Tuomisto, K. Saarinen, J. Zuñiga Pérez, and V. Muñoz-SanjoséPhotoluminescence and positron annihilation spectroscopy have been used to characterize and identify vacancy-type defects produced in ZnO films grown on sapphire by metal-organic chemical-vapor deposition. The photoluminescence of the samples in the near band edge region has been studied, paying... (Read more)
- 62. J. Appl. Phys. 99, 044105 (2006) , “Passivation of oxygen vacancy states in HfO2 by nitrogen”, K. Xiong, J. Robertson, and S. J. ClarkNitrogen is known to reduce leakage currents and charge trapping in high-dielectric-constant gate oxides such as HfO2. We show that this occurs because nitrogen, substituting for oxygen atoms next to oxygen vacancy sites, repels the occupied gap states due to the neutral and positively... (Read more)
- 63. J. Appl. Phys. 99, 043509 (2006) , “Influence of metal trapping on the shape of cavities induced by high energy He+ implantation”, R. El Bouayadi, G. Regula, M. Lancin, B. Pichaud, and M. DesvignesIn He implantation induced cavities highly contaminated with metals (Au, Ni, Pt) we found that, when no three-dimensional structure is observed, the shape of the cavities can be strongly modified depending on the nature of the metal and on its trapped quantity. The equilibrium shape of cavities is... (Read more)
- 64. J. Appl. Phys. 99, 023523 (2006) , “Characterization of 6H-SiC surfaces after ion implantation and annealing using positron annihilation spectroscopy and atomic force microscopy”, G. Brauer, W. Anwand, W. Skorupa, S. Brandstetter, and C. TeichertSystematic slow positron implantation spectroscopy (SPIS) and atomic force microscopy studies of various 6H-SiC samples are presented to clarify the role of conductivity type, crystal quality, ion implantation (B+,Al+, and N+), and annealing (1.650 °C) in... (Read more)
- 65. Phys. Rev. B 74, 245420 (2006) , “Energetics, structure, and long-range interaction of vacancy-type defects in carbon nanotubes: Atomistic simulations”, J. Kotakoski, A. V. Krasheninnikov,, and K. NordlundThe presence of vacancy clusters in carbon nanotubes has been assumed to explain the formation of carbon peapods and the difference between the experimentally measured and theoretical fracture strength of nanotubes. We use atomistic simulations at various levels of theory to study the... (Read more)
- 66. Phys. Rev. B 74, 245411 (2006) , “Vacancy defects and the formation of local haeckelite structures in graphene from tight-binding molecular dynamics”, Gun-Do Lee, C. Z. Wang, Euijoon Yoon, Nong-Moon Hwang, and K. M. HoThe dynamics of multivacancy defects in a graphene layer is investigated by tight-binding molecular dynamics simulations and by first principles calculation. The simulations show that four single vacancies in the graphene layer first coalesce into two double vacancies, each consisting of a... (Read more)
- 67. Phys. Rev. B 74, 235209 (2006) , “Comparison of two methods for circumventing the Coulomb divergence in supercell calculations for charged point defects”, A. F. Wright and N. A. ModineDensity-functional-theory calculations were performed for the unrelaxed +2 Si vacancy and +2 self-interstitial utilizing periodic boundary conditions and two different methods—the uniform background charge method and the local moment counter charge method—for circumventing the divergence... (Read more)
- 68. Phys. Rev. B 74, 235208 (2006) , “Theoretical study of the magnetism of Mn-doped ZnO with and without defects”, D. Iuan, B. Sanyal, and O. ErikssonWe calculate the exchange interaction parameters of a classical Heisenberg Hamiltonian for Mn-doped ZnO (Mn concentration between 5% and 20%) by an ab initio Korringa-Kohn-Rostoker coherent-potential-approximation method in the framework of density functional theory. A weak antiferromagnetic... (Read more)
- 69. Phys. Rev. B 74, 235207 (2006) , “Vacancy-enhanced ferromagnetism in Fe-doped rutile TiO2”, Jun Chen, Paul Rulis, Lizhi Ouyang, S. Satpathy, and W. Y. ChingBased on a series of supercell density functional calculations of Fe-doped TiO2 both with and without O vacancy (VO), we show that VO plays an important role in determining the magnetic properties of the dilute magnetic semiconductors (DMS). Without... (Read more)
- 70. Phys. Rev. B 74, 235201 (2006) , “Annealing of multivacancy defects in 4H-SiC”, W. E. Carlos, N. Y. Garces, E. R. Glaser, and M. A. FantonThe annealing behavior of defects observed in electron paramagnetic resonance (EPR) and photoluminescence (PL) is discussed. We consider the divacancy (the P6/P7 EPR centers) and a previously unreported EPR center that we suggest is a VC-VSi-VC... (Read more)
- 71. Phys. Rev. B 74, 214109 (2006) , “Inversion of defect interactions due to ordering in Sr1−3x/2LaxTiO3 perovskites: An atomistic simulation study”, B. S. Thomas, N. A. Marks, and Peter HarrowellSr1−3x/2LaxTiO3 perovskites exhibit large variations in radiation resistance and A-site vacancy ordering, depending on x and thermal history. In this study we use a combination of ab initio and classical simulation techniques... (Read more)
- 72. Phys. Rev. B 74, 205208 (2006) , “Formation energies, binding energies, structure, and electronic transitions of Si divacancies studied by density functional calculations”, R. R. Wixom and A. F. WrightAtomic configurations, formation energies, electronic transition energies, and binding energies of the silicon divacancy in the +1, 0, −1, and −2 charge states were obtained from density functional theory calculations. The calculations were performed using the local density approximation... (Read more)
- 73. Phys. Rev. B 74, 205207 (2006) , “Charge-dependent migration pathways for the Ga vacancy in GaAs”, Fedwa El-Mellouhi, Norm, and MousseauUsing a combination of the local-basis ab initio program SIESTA and the activation-relaxation technique we study the diffusion mechanisms of the gallium vacancy in GaAs. Vacancies are found to diffuse to the second neighbor using two different mechanisms, as well as to the first and fourth... (Read more)
- 74. Phys. Rev. B 74, 193405 (2006) , “Role of charge in destabilizing AlH4 and BH4 complex anions for hydrogen storage applications: Ab initio density functional calculations”, A. J. Du, Sean C. Smith, and G. Q. LuNaAlH4 and LiBH4 are potential candidate materials for mobile hydrogen storage applications, yet they have the drawback of being highly stable and desorbing hydrogen only at elevated temperatures. In this letter, ab initio density functional theory calculations reveal... (Read more)
- 75. Phys. Rev. B 74, 184117 (2006) , “Ab initio thermodynamic properties of point defects and O-vacancy diffusion in Mg spinels”, Zbigniew odziana and Jacek PiechotaWe report ab initio plane wave density functional theory studies of thermodynamic properties of isolated cation substitutions and oxygen vacancies in magnesium spinel, MgAl2O4. The formation enthalpy of Ca, Cu, and Zn substitutions of Mg cation indicate that transition... (Read more)
- 76. Phys. Rev. B 74, 174407 (2006) , “Superexchange in dilute magnetic dielectrics: Application to (Ti,Co)O2”, K. Kikoin and V. FleurovWe extend the model of ferromagnetic superexchange in dilute magnetic semiconductors to the ferromagnetically ordered highly insulating compounds (dilute magnetic dielectrics). The intrinsic ferromagnetism without free carriers is observed in oxygen-deficient films of anatase TiO2 doped... (Read more)
- 77. Phys. Rev. B 74, 174122 (2006) , “Lithium colloids and color center creation in electron-irradiated Li2NH observed by electron-spin resonance”, F. Beuneu, P. Vajda, Y. Nakamori, and S. OrimoWe have irradiated Li2NH powder with MeV electrons at room temperature and investigated the introduced defects with electron spin resonance. Conduction electron spin resonance indicates the presence of nanosize metallic Li colloids seen as a Lorentzian line with a g=2.0023 and a... (Read more)
- 78. Phys. Rev. B 74, 174120 (2006) , “Single-crystal silicon coimplanted by helium and hydrogen: Evolution of decorated vacancylike defects with thermal treatments”, C. Macchi, S. Mariazzi, G. P. Karwasz, R. S. Brusa, P. Folegati, S. Frabboni, and G. OttavianiSi p-type (100) samples were coimplanted at room temperature with He+ ions at 30 keV with a dose of 1×1016 ions/cm2 and successively with H+ ions at 24 keV with a dose of 1×1016 ions/cm2. A series of samples was... (Read more)
- 79. Phys. Rev. B 74, 174101 (2006) , “First-principles study of the intrinsic defects in PbFCl”, Bo Liu, Zeming Qi, and Chaoshu ShiFirst-principles pseudopotential calculations have been performed to investigate intrinsic defects including vacancies, interstitials, antisite defects, as well as Schottky and Frenkel defects in PbFCl crystals. For the isolated vacancies and interstitials, their formation energies are critically... (Read more)
- 80. Phys. Rev. B 74, 165404 (2006) , “Density functional study of gold atoms and clusters on a graphite (0001) surface with defects”, Jaakko Akola and Hannu HäkkinenAdsorption of gold atoms and clusters (N=6) on a graphite (0001) surface with defects has been studied using density functional theory. In addition to perfect graphite (0001), three types of surface defects have been considered: a surface vacancy (hole), a pyridinelike defect comprising three... (Read more)
- 81. Phys. Rev. B 74, 165116 (2006) , “Density-functional-theory calculations for the silicon vacancy”, A. F. WrightThe atomic configurations and formation energies of a silicon vacancy in the +2, +1, 0, −1, and −2 charge states have been computed using density-functional theory with norm-conserving pseudopotentials and a plane wave basis. Calculations were performed in simple cubic supercells using... (Read more)
- 82. Phys. Rev. B 74, 161203(R) (2006) , “Room-temperature manipulation and decoherence of a single spin in diamond”, R. Hanson, O. Gywat, and D. D. AwschalomWe report on room-temperature coherent manipulation of the spin of a single nitrogen-vacancy center in diamond and a study of its coherence as a function of magnetic field. We use magnetic resonance to induce Rabi nutations and apply a Hahn spin echo to remove the effect of low-frequency dephasing.... (Read more)
- 83. Phys. Rev. B 74, 161202 (2006) , “Deactivation of Li by vacancy clusters in ion-implanted and flash-annealed ZnO”, T. Moe Børseth, F. Tuomisto, J. S. Christensen, W. Skorupa, E. V. Monakhov, B. G. Svensson, and A. Yu. KuznetsovLi is present in hydrothermally grown ZnO at high concentrations and is known to compensate both n- and p-type doping due to its amphoteric nature. However, Li can be manipulated by annealing and ion implantation in ZnO. Fast, 20 ms flash anneals in the 9001400 °C range... (Read more)
- 84. Phys. Rev. B 74, 155204 (2006) , “Vibronic spectrum of c-BN measured with cathodoluminescence”, C. Manfredotti, R. Cossio, A. Lo Giudice, E. Vittone, and F. FizzottiAn extended vibronic spectrum (up to six phonon replicas) has been measured by low temperature cathodoluminescence in pure c-BN microcrystalline samples obtained by high temperature high pressure method. The zero phonon line, found at 3.573 eV, should be connected to a center identified... (Read more)
- 85. Phys. Rev. B 74, 153403 (2006) , “Doping and the unique role of vacancies in promoting the magnetic ground state in carbon nanotubes and C60 polymers”, Antonis N. Andriotis, R. Michael Sheetz, and Madhu MenonThe role of various types of defects in establishing the magnetic properties of the C60-based polymers and the single-wall carbon nanotubes is investigated. Comparing the role of carbon vacancies, and that of substitutional impurity atoms X (X=N, B, O, Si, P, and S) in... (Read more)
- 86. Phys. Rev. B 74, 144432 (2006) , “Role of defects in ferromagnetism in Zn1−xCoxO: A hybrid density-functional study”, C. H. PattersonExperimental studies of Zn1−xCoxO as thin films or nanocrystals have found ferromagnetism and Curie temperatures above room temperature and that p- or n-type doping of Zn1−xCoxO can change its magnetic... (Read more)
- 87. Phys. Rev. B 74, 125203 (2006) , “Density functional theory of structural transformations of oxygen-deficient centers in amorphous silica during hole trapping: Structure and formation mechanism of the Egamma[prime]" align="middle"> center”, T. Uchino and T. YokoWe investigate the hole trapping process of a neutral oxygen vacancy in amorphous silicon dioxide (a-SiO2) using cluster calculations based on the density functional theory (DFT) method. We show that trapping a hole at a neutral oxygen vacancy leads to the formation of several... (Read more)
- 88. Phys. Rev. B 74, 104303 (2006) , “Nitrogen-vacancy center in diamond: Model of the electronic structure and associated dynamics”, N. B. Manson, J. P. Harrison, and M. J. SellarsSymmetry considerations are used in presenting a model of the electronic structure and the associated dynamics of the nitrogen-vacancy center in diamond. The model accounts for the occurrence of optically induced spin polarization, for the change of emission level with spin polarization and for new... (Read more)
- 89. Phys. Rev. B 74, 045217 (2006) , “Vacancy clustering and diffusion in silicon: Kinetic lattice Monte Carlo simulations”, Benjamin P. Haley, Keith M. Beardmore, and Niels Grønbech-JensenDiffusion and clustering of lattice vacancies in silicon as a function of temperature, concentration, and interaction range are investigated by kinetic lattice Monte Carlo simulations. It is found that higher temperatures lead to larger clusters with shorter lifetimes on average, which grow by... (Read more)
- 90. Phys. Rev. B 74, 035112 (2006) , “Charge localization or itineracy at LaAlO3/SrTiO3 interfaces: Hole polarons, oxygen vacancies, and mobile electrons”, R. Pentcheva and W. E. PickettWhile correlated electron behavior is to be expected at oxide interfaces (IFs) involving Mott insulators, we show how strong correlations in the oxygen 2p states may be necessary to account for observed insulating behavior at charged (001)-IFs between the band insulators LaAlO3 and... (Read more)
- 91. Phys. Rev. B 74, 024106 (2006) , “Oxygen-vacancy-related dielectric anomaly in CaCu3Ti4O12: Post-sintering annealing studies”, C. C. Wang and L. W. ZhangThe influence of post-sintering annealing on the dielectric properties of CaCu3Ti4O12 was investigated in the temperature range form 200 to 400 K. A dielectric peak featuring thermally activated Debye-like behavior was observed around 340 K (100 Hz). This peak... (Read more)
- 92. Phys. Rev. B 73, 235213 (2006) , “Donor-vacancy complexes in Ge: Cluster and supercell calculations”, J. Coutinho, S. Öberg, V. J. B. Torres, M. Barroso, R. Jones, and P. R. BriddonWe present a comprehensive spin-density functional modeling study of the structural and electronic properties of donor-vacancy complexes (PV, AsV, SbV, and BiV) in Ge crystals. Special attention is paid to spurious results which are related to the choice of the boundary... (Read more)
- 93. Phys. Rev. B 73, 205203 (2006) , “First-principles study of intrinsic point defects in ZnO: Role of band structure, volume relaxation, and finite-size effects”, Paul Erhart, Karsten Albe, and Andreas KleinDensity-functional theory (DFT) calculations of intrinsic point defect properties in zinc oxide were performed in order to remedy the influence of finite-size effects and the improper description of the band structure. The generalized gradient approximation (GGA) with empirical self-interaction... (Read more)
- 94. Phys. Rev. B 73, 195206 (2006) , “Relaxations and bonding mechanism in Hg1–xCdxTe with mercury vacancy defect: First-principles study”, L. Z. Sun, Xiaoshuang Chen, Y. L. Sun, X. H. Zhou, Zh. J. Quan, He Duan, and Wei LuThe structural and electronic properties of the mercury vacancy defect in Hg1xCdxTe have been studied by combining the full-potential linear augmented plane wave and plane-wave pseudopotential method base on the density functional theory. Structural... (Read more)
- 95. Phys. Rev. B 73, 193203 (2006) , “Theoretical study of the phosphorus vacancy in ZnGeP2”, Xiaoshu Jiang, M. S. Miao, and Walter R. L. LambrechtFirst-principles calculations are presented for the phosphorus vacancy VP in ZnGeP2, using full-potential linearized muffin-tin orbital supercell local density functional theory calculations. We find the VP to have a high energy of formation compared to... (Read more)
- 96. Phys. Rev. B 73, 193202 (2006) , “First-principles study of point defects in rutile TiO2–x”, Eunae Cho, Seungwu Han, Hyo-Shin Ahn, Kwang-Ryeol Lee, Seong Keun Kim, and Cheol Seong HwangWe report our first-principles results on point defects in TiO2 in the rutile phase. Both the oxygen vacancy and titanium interstitial are considered. The size effect of the supercell has been examined and the localized state associated with the oxygen vacancy turns out to be sensitive to... (Read more)
- 97. Phys. Rev. B 73, 184105 (2006) , “Iron-oxygen vacancy defect association in polycrystalline iron-modified PbZrO3 antiferroelectrics: Multifrequency electron paramagnetic resonance and Newman superposition model analysis”, Hrvoje Metri, Rüdiger-A. Eichel, Klaus-Peter Dinse, Andrew Ozarowski, Johan van Tol, Louis Claude Brunel, Hans Kungl, Michael J. Hoffmann, Kristin A. Schönau, Michael Knapp, and Hartmut FuessBy utilizing multifrequency electron paramagnetic resonance (EPR) spectroscopy, the iron functional center in Fe3+-modified polycrystalline lead zirconate (PbZrO3) was studied. The single phase polycrystalline sample remained orthorhombic and antiferroelectric down to 20 K as... (Read more)
- 98. Phys. Rev. B 73, 115203 (2006) , “Thermal stability of gamma-irradiation-induced oxygen-deficient centers in silica”, S. Agnello and L. NuccioThe effects of isochronal thermal treatments on three -irradiation-induced point defects, named the E, ODC(II), and H(I) centers, are investigated in various types of commercial silica (a-SiO2). ODC(II) is investigated by means of photoluminescence spectroscopy,... (Read more)
- 99. Phys. Rev. B 73, 115202 (2006) , “Annealing of electron-, proton-, and ion-produced vacancies in Si”, S. Dannefaer, V. Avalos, D. Kerr, R. Poirier, V. Shmarovoz, and S. H. ZhangPositron lifetime and Doppler measurements were performed on float-zone-refined and variously doped Czochralski-grown Si. The samples were irradiated by various particles (e, p, Kr) with energies between 2 MeV and 245 MeV. Electron or proton irradiation gave rise to... (Read more)
- 100. Phys. Rev. B 73, 014111 (2006) , “Structure of SiO2/4H-SiC interface probed by positron annihilation spectroscopy”, M. Maekawa, A. Kawasuso, M. Yoshikawa, A. Miyashita, R. Suzuki, T. OhdairaThe structure of the SiO2/4H-SiC interface produced by dry oxidation has been studied using positron annihilation spectroscopy using energy-variable slow positron beams. Based on the Doppler broadening shape and wing parameter (S-W) correlation, the interface layer was... (Read more)
- 101. Phys. Rev. Lett. 97, 226401 (2006) , “Quasiparticle Corrections to the Electronic Properties of Anion Vacancies at GaAs(110) and InP(110)”, Magnus Hedström, Arno Schindlmayr, Günther Schwarz, and Matthias SchefflerWe propose a new method for calculating optical defect levels and thermodynamic charge-transition levels of point defects in semiconductors, which includes quasiparticle corrections to the Kohn-Sham eigenvalues of density-functional theory. Its applicability is demonstrated for anion vacancies at... (Read more)
- 102. Phys. Rev. Lett. 97, 135901 (2006) , “Vacancy-Assisted Diffusion in Silicon: A Three-Temperature-Regime Model”, Damien Caliste and Pascal PochetIn this Letter we report kinetic lattice Monte Carlo simulations of vacancy-assisted diffusion in silicon. We show that the observed temperature dependence for vacancy migration energy is explained by the existence of three diffusion regimes for divacancies. This characteristic has been rationalized... (Read more)
- 103. Phys. Rev. Lett. 97, 135502 (2006) , “29Si Hyperfine Structure of the Eα Center in Amorphous Silicon Dioxide”, G. Buscarino, S. Agnello, and F. M. GelardiWe report a study by electron paramagnetic resonance on the Eα point defect in amorphous silicon dioxide (a-SiO2). Our experiments were performed on γ-ray irradiated oxygen-deficient materials and pointed out that the 29Si... (Read more)
- 104. Phys. Rev. Lett. 97, 066101 (2006) , “Structure and Interconversion of Oxygen-Vacancy-Related Defects on Amorphous Silica”, Chin-Lung Kuo and Gyeong S. HwangAtomic structure and structural stability of neutral oxygen vacancies on amorphous silica are investigated using combined Monte Carlo and density functional calculations. We find that, unlike their bulk counterparts, the Si-Si dimer configuration of surface oxygen vacancies is likely to be unstable... (Read more)
- 105. Phys. Rev. Lett. 96, 55501 (2006) , “Divacancy in 4H-SiC”, N. T. Son, P. Carlsson, J. ul Hassan, E. Janzén, T. Umeda, J. Isoya, A. Gali, M. Bockstedte, N. Morishita, T. Ohshima, H. ItohElectron paramagnetic resonance and ab initio supercell calculations suggest that the P6/P7 centers, which were previously assigned to the photoexcited triplet states of the carbon vacancy-antisite pairs in the double positive charge state, are related to the triplet ground... (Read more)
- 106. Phys. Rev. Lett. 96, 145501 (2006) , “Identification of the Carbon Antisite-Vacancy Pair in 4H-SiC”, T. Umeda, N. T. Son, J. Isoya, E. Janzn, T. Ohshima, N. Morishita, H. Itoh, A. Gali, M. BockstedteThe metastability of vacancies was theoretically predicted for several compound semiconductors alongside their transformation into the antisite-vacancy pair counterpart; however, no experiment to date has unambiguously confirmed the existence of antisite-vacancy pairs. Using electron paramagnetic resonance and first principles calculations we identify the SI5 center as the carbon antisite-vacancy pair in the negative charge state (CSiVC-) in 4H-SiC. We suggest that this defect is a strong carrier-compensating center in n-type or high-purity semi-insulating SiC. (Read more)SiC| ENDOR EPR Theory electron-irradiation optical-spectroscopy thermal-meas./anneal-exp.| -1 -2 1.0eV~ 13C 29Si C1h C3v Carbon Csi EI5/6 HEI1 HEI5/6 Nitrogen P6/7 SI5 Silicon Vc antisite bistable/metastable dangling-bond n-type pair(=2) semi-insulating vacancy .inp files: SiC/SI5_C1h SiC/SI5_80K SiC/SI5_100K | last update: Takashi Fukushima
- 107. Appl. Phys. Lett. 87, 062105 (2005) , “Negative-U property of oxygen vacancy in cubic HfO2”, Y. P. Feng, A. T. L. Lim, M. F. LiOxygen vacancy in cubic HfO2 was investigated using first-principles calculation based on density functional theory and generalized gradient approximation. Five different charge states (V++, V+, V0, V, and... (Read more)
- 108. Appl. Phys. Lett. 87, 022903 (2005) , “Electron spin resonance investigation of oxygen-vacancy-related defects in BaTiO3 thin films”, V. V. Laguta, A. M. Slipenyuk, I. P. Bykov, M. D. Glinchuk, M. Maglione, D. Michau, J. Rosa, L. JastrabikThe Ti3+ center, based on a regular Ti site perturbed by an oxygen vacancy (VO), is identified by electron spin resonance (ESR) in textured BaTiO3 films. The center shows tetragonal symmetry along cubic 100 axes with g-factors: g=1.997,... (Read more)
- 109. Appl. Phys. Lett. 86, 143507 (2005) , “First-principles studies of the intrinsic effect of nitrogen atoms on reduction in gate leakage current through Hf-based high-k dielectrics”, N. Umezawa, K. Shiraishi, T. Ohno, H. Watanabe, T. Chikyow, K. Torii, K. Yamabe, K. Yamada, H. Kitajima, T. ArikadoThe atomistic effects of N atoms on the leakage current through HfO2 high-k gate dielectrics have been studied from first-principles calculations within the framework of a generalized gradient approximation (GGA). It has been found that the intrinsic effects of N atoms drastically... (Read more)
- 110. J. Appl. Phys. 97, 053704 (2005) , “The role of nitrogen-related defects in high-k dielectric oxides: Density-functional studies”, J. L. Gavartin, A. L. Shluger, A. S. Foster, G. I. BersukerUsing ab initio density-functional total energy and molecular-dynamics simulations, we study the effects of various forms of nitrogen postdeposition anneal (PDA) on the electric properties of hafnia in the context of its application as a gate dielectric in field-effect transistors. We... (Read more)
- 111. Phys. Rev. B 72, 45204 (2005) , “Electron-positron momentum distributions associated with isolated silicon vacancies in 3C-SiC”, A. Kawasuso, M. Yoshikawa, H. Itoh, T. Chiba, T. Higuchi, K. Betsuyaku, F. Redmann, R. Krause-RehbergTwo-dimensional angular correlation of annihilation radiation (2D-ACAR) and coincidence Doppler broadening (CDB) of annihilation radiation measurements have been performed on electron-irradiated n-type 3C-SiC in which isolated silicon vacancies are responsible for positron trapping.... (Read more)
- 112. Phys. Rev. B 72, 235208 (2005) , “Spin multiplicity and charge state of a silicon vacancy (TV2a) in 4H-SiC determined by pulsed ENDOR”, N. Mizuochi, S. Yamasaki, H. Takizawa, N. Morishita, T. Ohshima, H. Itoh, T. Umeda, and J. IsoyaIn this paper, we unambiguously re-determine the spin multiplicity of TV2a by pulsed electron nucleus double resonance technique. The TV2a center is one of the most commonly observed defects in 4H-SiC, and its origin was... (Read more)
- 113. Phys. Rev. B 72, 045219 (2005) , “Fluorine in Si: Native-defect complexes and the supression of impurity diffusion”, Giorgia M. Lopez, Vincenzo Fiorentini, Giuliana Impellizzeri, Salvatore Mirabella, Enrico NapolitaniThe transient enhanced diffusion of acceptor impurities severely affects the realization of ultrahigh doping regions in miniaturized Si-based devices. Fluorine codoping has been found to suppress this transient diffusion, but the mechanism underlying this effect is not understood. It has been proposed that fluorine-impurity or fluorine–native-defect interactions may be responsible. Here we clarify this mechanism combining first-principles theoretical studies of fluorine in Si and purposely designed experiments on Si structures containing boron and fluorine. The central interaction mechanism is the preferential binding of fluorine to Si-vacancy dangling bonds and the consequent formation of vacancy-fluorine complexes. The latter effectively act as traps for the excess self-interstitials that would normally cause boron transient enhanced diffusion. Instead, fluorine-boron interactions are marginal and do not play any significant role. Our results are also consistent with other observations such as native-defect trapping and bubble formation. (Read more)
- 114. Phys. Rev. B 71, 193204 (2005) , “Angular correlation of annihilation radiation associated with vacancy defects in electron-irradiated 6H-SiC”, A. Kawasuso, T. Chiba, T. HiguchiElectron-positron momentum distributions associated with vacancy defects in 6H-SiC after irradiation with 2-MeV electrons and annealing at 1000 °C have been studied using angular correlation of annihilation radiation measurements. It was confirmed that the above vacancy defects have... (Read more)
- 115. Phys. Rev. B 71, 193202 (2005) , “EPR and theoretical studies of negatively charged carbon vacancy in 4H-SiC”, T. Umeda, Y. Ishitsuka, J. Isoya, N. T. Son, E. Janzén, N. Morishita, T. Ohshima, H. Itoh, A. GaliCarbon vacancies (VC) are typical intrinsic defects in silicon carbides (SiC) and so far have been observed only in the form of positively charged states in p-type or semi-insulating SiC. Here, we present electron-paramagnetic-resonance (EPR) and photoinduced EPR (photo-EPR)... (Read more)
- 116. Phys. Rev. B 71, 125202 (2005) , “Positively charged carbon vacancy in three inequivalent lattice sites of 6H-SiC: Combined EPR and density functional theory study”, V. Ya. Bratus', T. T. Petrenko, S. M. Okulov, and T. L. PetrenkoThe Ky1, Ky2, and Ky3 centers are the dominant defects produced in the electron-irradiated p-type 6H-SiC crystals. The electron paramagnetic resonance study of these defects has been performed in the temperature range of 4.2300 K at... (Read more)
- 117. Phys. Rev. B 71, 035213 (2005) , “Possibility for the electrical activation of the carbon antisite by hydrogen in SiC”, A. Gali, P. Deák, N. T. Son, and E. JanzénCalculations predict the carbon antisite to be the most abundant intrinsic defect in silicon carbide in a wide range of doping. The isolated carbon antisite is, however, optically and electronically inactive, therefore, difficult to observe by usual experimental techniques. However, CSi... (Read more)
- 118. Appl. Phys. Lett. 85, 1538 (2004) , “Observation of fluorine-vacancy complexes in silicon”, P. J. Simpson, Z. Jenei, P. Asoka-Kumar, R. R. Robison, M. E. LawWe show direct evidence, obtained by positron annihilation spectroscopy, for the complexing of fluorine with vacancies in silicon. Both float zone and Czochralski silicon wafers were implanted with 30 keV fluorine ions to a fluence of 2×1014 ions/cm2, and studied in the... (Read more)
- 119. Appl. Phys. Lett. 84, 3406-3408 (2004) , “Structure of 6H silicon carbide/silicon dioxide interface trapping defects”, David J. Meyer, Nathaniel A. Bohna, and Patrick M. LenahanWe utilize spin-dependent recombination (SDR) to observe deep level trap defects at or very near the interface of 6H silicon carbide and the SiO2 gate dielectric in SiC metal-oxide-semiconductor field effect transistors. The SDR response is strongly correlated to SiC/SiO2... (Read more)
- 120. Eur. Phys. J. Appl. Phys. 27, 13-19 (2004) , “Measurement of process-induced defects in Si sub-micron devices by combination of EDMR and TEM”, T. Umeda, A. Toda, Y. MochizukiProcess-induced defects are a serious issue for modern sub-micron Si LSIs. To characterize such defects, two different techniques are useful: electrically detected magnetic resonance (EDMR) and transmission electron microscope (TEM), which can detect small (point) and extended defects, respectively. We applied EDMR and TEM to the issue of defect-induced leakage currents in dynamic-random-access memory (DRAM) cells. For our DRAM samples (a 0.25- μm-rule series), although TEM showed no extended defects, EDMR successfully detected two types of point defects: V2+O x (Si divacancy-oxygen complexes) and larger Si vacancies (at least larger than V6). We confirmed that these defects are the source of DRAM leakage currents. The observed defects were formed by ion implantation processes, but were more thermally stable than those in bulk Si crystals. The origins of this enhanced stability are attributed to the presence of oxygen atoms and a strong mechanical strain in LSIs. To clarify the origin of the complicated strain in LSI structures, we can directly measure the local-strain distribution in DRAM samples by means of convergent-beam electron diffraction (CBED) using TEM, which provides us with a valuable hint for understanding the formation mechanism of process-induced defects. (Read more)
- 121. J. Appl. Phys. 96, 2406-2408 (2004) , “Annealing behavior of the carbon vacancy in electron-irradiated 4H-SiC”, Z. Zolnai, N. T. Son, C. Hallin, and E. JanzénElectron paramagnetic resonance (EPR) was used to study the annealing behavior of the positively charged carbon vacancy (EI5 center) in electron-irradiated 4H-SiC. At ~1000 °C the EPR signal of the defect starts decreasing gradually. Clear ligand hyperfine structure is still observed after... (Read more)
- 122. Mater. Sci. Forum 457-460, 465 (2004) , “EPR and pulsed ENDOR study of EI6 and related defects in 4H-SiC”, T. Umeda, Y. Ishitsuka, J. Isoya, N. Morishita, T. Ohshima, T. Kamiya
- 123. Mater. Sci. Forum 457-460, 437 (2004) , “Defects in high-purity semi-insulating SiC”, N. T. Son, B. Magnusson, Z. Zolnai, A. Ellison, E. Janzén
- 124. Phys. Rev. B 70, 245204 (2004) , “Silicon vacancy annealing and DI luminescence in 6H-SiC”, M. V. B. Pinheiro, E. Rauls, U. Gerstmann, S. Greulich-Weber, H. Overhof, and J.-M. SpaethCombining electron paramagnetic resonance measurements with ab initio calculations, we identify the VCCSi(SiCCSi) complex as a second annealing product of the silicon vacancy via an analysis of resolved carbon hyperfine interactions and of... (Read more)
- 125. Phys. Rev. B 70, 235212 (2004) , “EPR and theoretical studies of positively charged carbon vacancy in 4H-SiC”, T. Umeda, J. Isoya, N. Morishita, T. Ohshima, T. Kamiya, A. Gali, P. Deák, N. T. Son, E. JanzénThe carbon vacancy is a dominant defect in 4H-SiC, and the "EI5" electron-paramagnetic-resonance (EPR) spectrum originates from positively charged carbon vacancies (VC+) at quasicubic sites. The observed state for EI5, however, has been attributed to a... (Read more)
- 126. Phys. Rev. B 70, 201204(R) (2004) , “Annealing of vacancy-related defects in semi-insulating SiC”, U. Gerstmann, E. Rauls, and H. OverhofThe annealing of P6/P7 centers (VCCSi pairs) in the presence of carbon vacancies in high concentrations typical for semi-insulating (SI) silicon carbide (SiC) is studied theoretically. The calculated hyperfine parameters support the suggestion of a negatively... (Read more)
- 127. Phys. Rev. B 70, 195344 (2004) , “Ab initio study of structural and electronic properties of planar defects in Si and SiC”, C. Raffy, J. Furthmüller, J.-M. Wagner, and F. BechstedtWe present ab initio calculations for internal interfaces in Si and SiC. Density-functional calculations within the local-density approximation and the pseudopotential-plane-wave approach are performed to understand the effect of such two-dimensional defects on the electronic properties. We... (Read more)
- 128. Phys. Rev. B 70, 115203 (2004) , “Different roles of carbon and silicon interstitials in the interstitial-mediated boron diffusion in SiC”, Michel Bockstedte, Alexander Mattausch, and Oleg PankratovThe interstitial and vacancy mediated boron diffusion in silicon carbide is investigated with an ab initio method. The boron interstitials in p-type and n-type materials are found to be far more mobile than the boron-vacancy complexes. A kick-out mechanism and an interstitialcy... (Read more)
- 129. Phys. Rev. B 70, 085202 (2004) , “Reassignment of phosphorus-related donors in SiC”, E. Rauls, M. V. B. Pinheiro, S. Greulich-Weber, and U. GerstmannCombining efficient density-functional based tight-binding molecular dynamics with ab initio calculations, we show that despite higher formation energies the incorporation of phosphorus at the carbon sublattice is favored by kinetic effects during the annealing processes. Based on the... (Read more)
- 130. Phys. Rev. B 69, 45207 (2004) , “Intrinsic defects in GaN. I. Ga sublattice defects observed by optical detection of electron paramagnetic resonance”, K. H. Chow, L. S. Vlasenko, P. Johannesen, C. Bozdog, G. D. Watkins, Akira Usui, Haruo Sunakawa, Chiaki Sasaoka, Masashi MizutaIrradiation of GaN by 2.5-MeV electrons in situ at 4.2 K produces a broad photoluminescence (PL) band centered at 0.95 eV. Optical detection of electron paramagnetic resonance (ODEPR) in the band reveals two very similar, but distinct, signals, L5 and L6, which we identify as interstitial... (Read more)
- 131. Phys. Rev. B 69, 245205 (2004) , “Atomistic study of intrinsic defect migration in 3C-SiC”, Fei Gao, William J. Weber, M. Posselt, and V. BelkoAtomic-scale computer simulations, both molecular dynamics (MD) and the nudged-elastic band methods, have been applied to investigate long-range migration of point defects in cubic SiC (3C-SiC) over the temperature range from 0.36Tm to 0.95Tm (melting... (Read more)
- 132. Phys. Rev. B 69, 235202 (2004) , “Ab initio study of the annealing of vacancies and interstitials in cubic SiC: Vacancy-interstitial recombination and aggregation of carbon interstitials”, Michel Bockstedte, Alexander Mattausch, and Oleg PankratovThe annealing kinetics of mobile intrinsic defects in cubic SiC is investigated by an ab initio method based on density-functional theory. The interstitial-vacancy recombination, the diffusion of vacancies, and interstitials to defect sinks (e.g., surfaces or dislocations) as well as the... (Read more)
- 133. Phys. Rev. B 69, 233202 (2004) , “Diffusion of hydrogen in perfect, p-type doped, and radiation-damaged 4H-SiC”, B. Aradi, P. Deák, A. Gali, N. T. Son, E. JanzénThe diffusion of interstitial atomic hydrogen in 4H-SiC was investigated theoretically, using the local density approximation of density functional theory. We have found that the diffusion barrier in the perfect crystal is 0.6 eV. Comparing this value with the calculated zero point vibration... (Read more)
- 134. Phys. Rev. B 69, 125203 (2004) , “First-principles studies of the diffusion of B impurities and vacancies in SiC”, R. Rurali, E. Hernández, P. Godignon, J. Rebollo, and P. OrdejónIn this paper we analyze, by means of first-principles electronic structure calculations, the structural, energetic, and diffusive properties of B impurities in SiC as well as of vacancies. We focus our study on (i) determining the equilibrium structures of the impurity in the lattice by means of... (Read more)
- 135. Phys. Rev. B 69, 121201(R) (2004) , “EPR identification of two types of carbon vacancies in 4H-SiC”, T. Umeda, J. Isoya, N. Morishita, T. Ohshima, and T. KamiyaThe EI5 and EI6 centers are typical intrinsic defects in radiation-damaged and semi-insulating 4H-SiC. So far, their origins have been assigned to positively charged carbon vacancies (VC+) and silicon antisites (SiC+), respectively. However,... (Read more)
- 136. Phys. Rev. B 69, 035205 (2004) , “Metastable and nonmetastable recombination-induced defect reactions involving a hydrogen complex with a silicon vacancy in SiC”, Yaroslav KoshkaThe nontrivial recombination-induced behavior of the well-known low-temperature photoluminescence of the hydrogen complex with a silicon vacancy (VSi-H) has been previously reported by different authors. It was known to be limited to the metastable quenching and/or growth. In this... (Read more)
- 137. Phys. Rev. Lett. 93, 255502 (2004) , “Formation of Thermal Vacancies in Highly As and P Doped Si”, V. Ranki and K. SaarinenUsing positron annihilation measurements we observed the formation of thermal vacancies in highly As and P doped Si. The vacancies start to form at temperatures as low as 650 K and are mainly undecorated at high temperatures. Upon cooling the vacancies form stable vacancy-impurity complexes such as... (Read more)
- 138. Phys. Rev. Lett. 93, 245901 (2004) , “Ab Initio Calculations to Model Anomalous Fluorine Behavior”, Milan Diebel, Scott T. Dunhammplanted fluorine is observed to behave unusually in silicon, manifesting apparent uphill diffusion and reducing diffusion and enhancing activation of boron. In order to investigate fluorine behavior, we calculate the energy of fluorine defect structures in the framework of density functional theory. In addition to identifying the ground-state configuration and diffusion migration barrier of a single fluorine atom in silicon, a set of energetically favorable fluorine defect structures were found (FnVm). The decoration of vacancies and dangling silicon bonds by fluorine suggests that fluorine accumulates in vacancy-rich regions, which explains the fluorine redistribution behavior reported experimentally. (Read more)
- 139. Phys. Rev. Lett. 92, 135502 (2004) , “Hydrogen Incorporation in Diamond: The Vacancy-Hydrogen Complex”, C. Glover, M. E. Newton, P. M. Martineau, S. Quinn, D. J. TwitchenWe report the identification of the vacancy-hydrogen complex in single crystal diamond synthesized by chemical vapor deposition. The S = 1 defect is observed by electron paramagnetic resonance in the negative charge state. The hydrogen atom is bonded to one of the carbon atoms neighboring the... (Read more)
- 140. Phys. Rev. Lett. 92, 125504 (2004) , “Low Energy Electron Irradiation Induced Deep Level Defects in 6H–SiC: The Implication for the Microstructure of the Deep Levels E1/E2”, X. D. Chen, C. L. Yang, M. Gong, W. K. Ge, S. Fung, C. D. Beling, J. N. Wang, M. K. Lui, and C. C. LingN-type 6HSiC samples irradiated with electrons having energies of Ee = 0.2, 0.3, 0.5, and 1.7 were studied by deep level transient technique. No deep level was detected at below 0.2 MeV irradiation energy while for Ee0.3 MeV,... (Read more)
- 141. J. Appl. Phys. 94, 7105-7111 (2003) , “Electrically detected magnetic resonance of ion-implantation damage centers in silicon large-scale integrated circuits”, T. Umeda, Y. Mochizuki, K. Okonogi, K. HamadaWe used electrically detected magnetic resonance to study the microscopic structure of ion-implantation-induced point defects that remained in large-scale Si integrated circuits (Si LSIs). Two types of defects were detected in the source/drain (n+-type) region of... (Read more)
- 142. Phys. Rev. B 68, 205201 (2003) , “Ab initio study of the migration of intrinsic defects in 3C-SiC”, Michel Bockstedte, Alexander Mattausch, and Oleg PankratovThe diffusion of intrinsic defects in 3C-SiC is studied using an ab initio method based on density functional theory. The vacancies are shown to migrate on their own sublattice. The carbon split-interstitials and the two relevant silicon interstitials, namely the tetrahedrally... (Read more)
- 143. Phys. Rev. B 68, 165206 (2003) , “EPR studies of the isolated negatively charged silicon vacancies in n-type 4H- and 6H-SiC: Identification of C3v symmetry and silicon sites”, N. Mizuochi, S. Yamasaki, H. Takizawa, N. Morishita, T. Ohshima, H. Itoh, and J. IsoyaThe isolated negatively charged silicon vacancy (VSi-" align="middle">) in the hexagonal lattices of 4H- and 6H-SiC has been studied by electron paramagnetic resonance (EPR). The local structure was suggested to have Td symmetry from the... (Read more)
- 144. Phys. Rev. B 68, 155208 (2003) , “Theoretical study of vacancy diffusion and vacancy-assisted clustering of antisites in SiC”, E. Rauls, Th. Frauenheim, A. Gali, P. DeákUsing the self-consistent-charge density-functional-based tight-binding (SCC-DFTB) method, we have investigated the migration of vacancies at high temperatures, taking into account the entropy contribution to the Gibbs free energy. We have found that the energy barrier for sublattice migration of... (Read more)
- 145. Phys. Rev. B 68, 12102 (2003) , “240 GHz electron paramagnetic resonance studies of intrinsic defects in as-grown 4H SiC”, Valery V. Konovalov, Mary Ellen Zvanut, Johan van Tol240 GHz electron paramagnetic resonance (EPR) measurements of as-grown nominally semi-insulating 4H SiC detected two well-separated centers ID1 and ID2. The EPR parameters of ID1 and ID2 coincide with that of EI5 and EI6 centers previously detected in 2-MeV electron-irradiated p-type... (Read more)
- 146. Phys. Rev. B 68, 085202 (2003) , “Physics and chemistry of hydrogen in the vacancies of semiconductors”, Bernadett Szûcs, Adam Gali, Zoltán Hajnal, Peter Deák, and Chris G. Van de WalleHydrogen is well known to cause electrical passivation of lattice vacancies in semiconductors. This effect follows from the chemical passivation of the dangling bonds. Recently it was found that H in the carbon vacancy of SiC forms a three-center bond with two silicon neighbors in the vacancy, and... (Read more)
- 147. Phys. Rev. B 67, 205202 (2003) , “Formation and annealing of nitrogen-related complexes in SiC”, U. Gerstmann, E. Rauls, Th. Frauenheim, and H. OverhofWe propose a mechanism for the annealing of vacancy-related defects in SiC, based on ab initio total energy calculations. Our mechanism is based on the formation and migration of carbon and nitrogen split interstitials resulting in CSi(NC)n or... (Read more)
- 148. Phys. Rev. B 67, 193102 (2003) , “Signature of intrinsic defects in SiC: Ab initio calculations of hyperfine tensors”, Michel Bockstedte, Matthias Heid, and Oleg PankratovTo reveal the microscopic origin of the spin-resonance centers in 3C- and 4H-SiC, we perform first-principles calculations of the hyperfine tensors for vacancy-related defects and interstitials. The calculations for the silicon vacancy corroborates the earlier experimental identification. The... (Read more)
- 149. Phys. Rev. B 67, 125207 (2003) , “Silicon and carbon vacancies in neutron-irradiated SiC: A high-field electron paramagnetic resonance study”, S. B. Orlinski, J. Schmidt, E. N. Mokhov, P. G. BaranovElectron-paramagnetic-resonance (EPR) and electron-spin-echo (ESE) studies have been performed that show that isolated VSi-, VSi0, and VC vacancies are the dominant intrinsic paramagnetic defects in SiC treated by room-temperature neutron... (Read more)
- 150. Phys. Rev. Lett. 91, 109601 (2003) , “Comment on "Identification of Lattice Vacancies on the Two Sublattices of SiC"”, J. W. SteedsA Comment on the Letter by A. A. Rempel et al., Phys. Rev. Lett. 89, 185501 (2002). The authors of the Letter offer a Reply.... (Read more)
- 151. Phys. Rev. Lett. 90, 155901 (2003) , “Fluorine in Silicon: Diffusion, Trapping, and Precipitation”, X. D. Pi, C. P. Burrows, P. G. ColemanThe effect of vacancies on the behavior of F in crystalline Si has been elucidated experimentally for the first time. With positron annihilation spectroscopy and secondary ion mass spectroscopy, we find that F retards recombination between vacancies (V) and interstitials (I) because V and I trap F to form complexes. F diffuses in the V-rich region via a vacancy mechanism with an activation energy of 2.12±0.08 eV. After a long annealing time at 700ºC, F precipitates have been observed by cross-section transmission electron microscopy which are developed from the V-type defects around the implantation range and the I-type defects at the end of range. (Read more)
- 152. Phys. Rev. Lett. 90, 137402 (2003) , “Vacancy Defects as Compensating Centers in Mg-Doped GaN”, S. Hautakangas, J. Oila, M. Alatalo, K. Saarinen, L. LIszkay, D. Seghier, H.P. GislasonWe apply positron annihilation spectroscopy to identify VNMgGa complexes as native defects in Mg-doped GaN. These defects dissociate in postgrowth annealings at 500800 °C. We conclude that VNMgGa complexes contribute to... (Read more)
- 153. Physica B 340-342, 151 (2003) , “Optical and magnetic resonance signatures of deep levels in semi-insulating 4H SiC”, W. E. Carlos, E. R. Glaser and B. V. ShanabrookWe have studied semi-insulating (SI) 4H SiC grown by physical vapor transport (PVT) and by high-temperature chemical vapor deposition (HTCVD) using electron paramagnetic resonance (EPR) and infrared photoluminescence (IR-PL) to better understand the defect(s) responsible for the SI behavior.... (Read more)
- 154. Physica B 340-342, 15-24 (2003) , “Defects in SiC”, E. Janzén, I. G. Ivanov, N. T. Son, B. Magnusson, Z. Zolnai, A. Henry, J. P. Bergman, L. Storasta, F. CarlssonRecent results from studies of shallow donors, pseudodonors, and deep level defects in SiC are presented. The selection rules for transitions between the electronic levels of shallow donors in 4H–SiC in the dipole approximation are derived and the ionization energy for the N donor at... (Read more)
- 155. Appl. Phys. Lett. 81, 3945 (2002) , “Photoexcitation-electron-paramagnetic-resonance studies of the carbon vacancy in 4H-SiC”, N. T. Son, B. Magnusson, and E. JanzénPhotoexcitation-electron-paramagnetic-resonance (photo-EPR) studies were performed on p-type 4H-SiC irradiated with 2.5 MeV electrons. At W-band frequencies (~95 GHz) different EPR spectra could be well separated, allowing a reliable determination of the ground state levels of the... (Read more)
- 156. Appl. Phys. Lett. 81, 1818 (2002) , “Interface structures generated by negative-bias temperature instability in Si/SiO2 and Si/SiOxNy interfaces”, J. Ushio, T. Maruizumi, K. Kushida-AbdelghafarWe used a density functional method to investigate the mechanism of negative-bias temperature instability (NBTI) and resultant structural changes of Si/SiO2 and Si/SiOxNy interfaces. The reaction energies for the water- and hydrogen-originated... (Read more)
- 157. Appl. Phys. Lett. 80, 410 (2002) , “The level position of a deep intrinsic defect in 4H-SiC studied by photoinduced electron paramagnetic resonance”, M. E. Zvanut and V. V. KonovalovPhotoinduced electron paramagnetic resonance studies performed on nominally semi-insulating, high purity 4H-SiC have revealed charge transfer from an intrinsic defect (ID) to both the shallow boron acceptor and nitrogen donor. At 4 K, incident photon energy between 1.0 and 1.7 eV produces an... (Read more)
- 158. Phys. Rev. B 66, 235202 (2002) , “Continuous-wave and pulsed EPR study of the negatively charged silicon vacancy with S=3/2 and C3v symmetry in n-type 4H-SiC”, N. Mizuochi, S. Yamasaki, H. Takizawa, N. Morishita, T. Ohshima, H. Itoh, J. IsoyaThe TV2a center, which was suggested to be the excited triplet state (S=1) of the neutral silicon vacancy related defect [Sörman et al., Phys. Rev. B 61, 2613 (2000)] in the electron-irradiated n-type 4H-SiC has been studied by continuous wave and pulsed electron paramagnetic resonance... (Read more)
- 159. Phys. Rev. B 66, 155214 (2002) , “Ligand hyperfine interaction at the neutral silicon vacancy in 4H- and 6H-SiC”, Mt. Wagner, N. Q. Thinh, N. T. Son, W. M. Chen, E. Janzén, P. G. Baranov, E. N. Mokhov, C. Hallin, J. L. LindströmThe silicon vacancy in its neutral charge state (VSi) has been unambiguously identified in 4H- and 6H-SiC. This was achieved by observation of ligand hyperfine interaction with the four carbon atoms in the nearest-neighbor shell and the twelve silicon atoms in the next-nearest-neighbor... (Read more)
- 160. Phys. Rev. B 65, 085202 (2002) , “Divacancy in 3C- and 4H-SiC: An extremely stable defect”, L. Torpo, T. E. M. Staab, R. M. NieminenUsing first-principles calculations for divacancy defects in 3C- and 4H-SiC, we determine their formation energies and stability, their ionization levels, and relaxed geometries (symmetry point groups) for neutral as well as for charged states. For 4H-SiC all four possible nearest-neighbor divacancy... (Read more)
- 161. Phys. Rev. Lett. 89, 185501 (2002) , “Identification of Lattice Vacancies on the Two Sublattices of SiC”, A. A. Rempel, W. Sprengel, K. Blaurock, K. J. Reichle, J. Major, and H.-E. SchaeferThe identification of atomic defects in solids is of pivotal interest for understanding atomistic processes and solid state properties. Here we report on the exemplary identification of vacancies on each of the two sublattices of SiC by making use of (i) electron irradiation, (ii) measurements of... (Read more)
- 162. Appl. Phys. Lett. 79, 3950 (2001) , “Annealing behavior of vacancies and Z1/2 levels in electron-irradiated 4H–SiC studied by positron annihilation and deep-level transient spectroscopy”, A. Kawasuso, F. Redmann, R. Krause-Rehberg, M. Weidner, T. Frank, G. Pensl, P. Sperr, W. Triftshäuser, H. ItohAnnealing behavior of vacancies and the Z1/2 levels in n-type 4HSiC epilayers after 2 MeV electron irradiation has been studied using positron annihilation and deep-level transient spectroscopy. Isochronal annealing studies indicate that silicon vacancy-related defects... (Read more)
- 163. J. Appl. Phys. 90, 6026-6031 (2001) , “Oxygen-Related Defects in Low-Dose Separation-by-Implanted Oxygen Wafers Probed by Monoenergetic Positron Beams”, A. Uedono, Z. Q. Chen, A. Ogura, H. Ono, R. Suzuki, T. Ohdaira, T. Mikado.The depth distributions of oxygen-related defects in separation-by-implanted oxygen wafers were determined from measurements of Doppler broadening spectra of the annihilation radiation. Vacanyoxygen complexes were introduced by implanting 180-keV oxygen at (26)×1017 ... (Read more)
- 164. J. Appl. Phys. 90, 3377 (2001) , “Vacancies and deep levels in electron-irradiated 6H SiC epilayers studied by positron annihilation and deep level transient spectroscopy”, A. Kawasuso, F. Redmann, R. Krause-Rehberg, T. Frank, M. Weidner, G. Pensl, P. Sperr, H. ItohThe annealing behavior of defects in n-type 6H SiC epilayers irradiated with 2 MeV electrons have been studied using positron annihilation and deep level transient spectroscopy. Vacancy-type defects are annealed at 500700 °C and 12001400 °C. From the analysis of... (Read more)
- 165. J. Phys.: Condens. Matter 13, 6203-6231 (2001) , “Comprehensive ab initio study of properties of monovacancies and antisites in 4H-SiC”, L. Torpo, M. Marlo, T. E. M. Staab, R. M. NieminenWe present results of ab initio calculations for the electronic and atomic structures of monovacancies and antisite defects in 4H-SiC in all possible charge states. The calculations make use of a plane-wave pseudopotential method based on density-functional theory and the local spin-density... (Read more)
- 166. Phys. Rev. B 64, 245212 (2001) , “Structure of the silicon vacancy in 6H-SiC after annealing identified as the carbon vacancy-carbon antisite pair”, Th. Lingner, S. Greulich-Weber, J.-M. Spaeth, U. Gerstmann, E. Rauls, Z. Hajnal, Th. Frauenheim, H. OverhofWe investigated radiation-induced defects in neutron-irradiated and subsequently annealed 6H-silicon carbide (SiC) with electron paramagnetic resonance (EPR), the magnetic circular dichroism of the absorption (MCDA), and MCDA-detected EPR (MCDA-EPR). In samples annealed beyond the annealing... (Read more)
- 167. Phys. Rev. B 64, 245208 (2001) , “Ab initio and empirical-potential studies of defect properties in 3C-SiC”, Fei Gao, Eric J. Bylaska, William J. Weber, L. René CorralesDensity functional theory (DFT) is used to study the formation and properties of native defects in 3C-SiC. Extensive calculations have been carried out to determine the formation of point defects and the stability of self-interstitials. Although there is good agreement in the formation of vacancies... (Read more)
- 168. Phys. Rev. B 63, 245202 (2001) , “Ab initio density-functional supercell calculations of hydrogen defects in cubic SiC”, B. Aradi, A. Gali, P. Deák, J. E. Lowther, N. T. Son, E. Janzén, W. J. ChoykeBased on ab initio density-functional calculations in supercells of 3C-SiC, the stable configurations of hydrogen and dihydrogen defects have been established. The calculated formation energies are used to give semiquantitative estimates for the concentration of hydrogen in SiC after chemical vapor... (Read more)
- 169. Phys. Rev. B 63, 201201(R) (2001) , “Carbon vacancy-related defect in 4H and 6H SiC”, N. T. Son, P. N. Hai, E. JanzénAn electron paramagnetic resonance (EPR) spectrum was observed at temperatures above 25 K in p-type 4H and 6H SiC irradiated with electrons. The center has C3V symmetry with an electron spin S=1/2. Using high frequency (?95 GHz) EPR it was possible to obtain the detailed hyperfine... (Read more)
- 170. Phys. Rev. Lett. 87, 45502 (2001) , “Silicon Antisite in 4H SiC”, N. T. Son, P. N. Hai, E. JanzénElectron paramagnetic resonance spectrum with C3V symmetry and a spin S = 1/2 has been observed in p-type, electron-irradiated 4H SiC. Based on the observed 29Si hyperfine structures it is suggested that the defect is the isolated silicon antisite (SiC). The spin... (Read more)
- 171. Physica B 308-310, 637 (2001) , “Calculation of hyperfine parameters of positively charged carbon vacancy in SiC”, T. T. Petrenko, T. L. Petrenko, V. Ya. Bratus and J. L. MongeTheoretical simulation of hyperfine parameters for the nearest and next-nearest neighbor atoms of VC+ in SiC has been performed for the cubic and hexagonal clusters. The gradient-corrected all-electron DFT calculations with Becke's three-parameter functional have been performed by the use of split... (Read more)
- 172. Physica B 308-310, 621 (2001) , “Positively charged carbon vacancy in 6H–SiC: EPR study”, V. Ya. Bratus, I. N. Makeeva, S. M. Okulov, T. L. Petrenko, T. T. Petrenko and H. J. von BardelebenThe low-temperature X-band EPR study of Ky1 and Ky2 centers assigned to positively charged carbon vacancy (VC+) in two quasicubic sites of 6H–SiC crystal is presented. The CS symmetry, spin S=1/2 and close coincidence of the g-tensor components have been revealed. The principal values of... (Read more)
- 173. Physica B 302-303, 249-256 (2001) , “Hydrogen-Enhanced Clusterization of Intrinsic Defects and Impurities in Silicon”, B. N. Mukashev, Kh. A. Abdullin, Yu. V. Gorelkinskii, M. F. Tamendarov and S. Zh. TokmoldinFormation of intrinsic and impurity defect complexes in hydrogenated monocrystalline silicon is studied. Hydrogen was incorporated into samples by different ways: either by proton implantation at 80 and 300 K, or by annealing at 1250°C for 30–60 min in a sealed quartz ampoule containing... (Read more)
- 174. J. Phys.: Condens. Matter 12, 3369 (2000) , “Local electronic structure around vacancies and vacancy-antisite complexes in ?-SiC”, G. Cubiotti, Yu. Kucherenko, A. Yaresko, A. Perlov, V. AntonovThe local electronic structure around vacancies and vacancy-antisite complexes in cubic SiC has been calculated by means of the LMTO (linear muffin-tin orbital) method and the supercell approach. In order to improve the description of the electronic structure near the energy gap, the... (Read more)
- 175. Mater. Sci. Eng. B 73, 60-63 (2000) , “EPR study of He-implanted Si”, B. Pivac, B. Rakvin, R. Tonini, F. Corni and G. OttavianiElectron paramagnetic resonance has been used to study the influence of thermal treatments on defect evolution in helium-implanted Czochralski single-crystal silicon. It is shown that the thermal treatment induces helium migration and capturing by vacancy clusters that transform into pressurized... (Read more)
- 176. Mater. Sci. Eng. B 71, 249 (2000) , “New (S=1) EPR AA17 center in silicon — microplatelets or precursor of platelets?”, Yu. V. Gorelkinskii, Kh. A. Abdullin, B. N. Mukashev.New (S=1) EPR spectrum (labeled Si-AA17) is observed in irradiated high-purity hydrogen-contained silicon after annealing at ≥200°C. The AA17 defect has D3d symmetry with g=2.0028, g=2.0106; A(29Si)=175.0 MHz, A=89.0 MHz; and D=±33.6 MHz, D=±16.8 MHz. It is paramagnetic in a... (Read more)
- 177. Phys. Rev. B 62, 8016 (2000) , “Isochronal annealing studies of n-type 6H-SiC with positron lifetime spectroscopy”, C. C. Ling, C. D. Beling, S. Fungn-type 6H silicon carbide has been studied using positron lifetime spectroscopy with isochronal annealing temperatures of 400, 650, 900, 1200, and 1400 °C. In the as-grown sample, we have identified the VSi vacancy, the VCVSi divacancy, and probably the VC... (Read more)
- 178. Phys. Rev. B 62, 6854 (2000) , “Spin state of vacancies: From magnetic Jahn-Teller distortions to multiplets”, A. Zywietz, J. Furthmüller, and F. BechstedtThe spin configuration of isoelectronic vacancies surrounded by first-row atoms is studied within density-functional theory (DFT) using the local spin density approximation. Allowing for a symmetry break in the electronic system, a mixed-spin state is found to be lowest in energy. It is accompanied... (Read more)
- 179. Phys. Rev. B 62, 10841 (2000) , “Vacancy defects in p-type 6H-SiC created by low-energy electron irradiation”, H. J. von Bardeleben, J. L. Cantin, L. Henry, M. F. BartheThe intrinsic defects in p-type 6H-SiC:Al generated by electron irradiation at 300 keV, which is close to the threshold of the silicon atom displacement, have been studied by electron paramagnetic resonance spectroscopy. We observed two dominant irradiation-induced paramagnetic defects:?(i) a... (Read more)
- 180. Phys. Rev. B 62, 10126 (2000) , “Proton-implantation-induced defects in n-type 6H- and 4H-SiC: An electron paramagnetic resonance study”, H. J. von Bardeleben, J. L. Cantin, I. Vickridge, G. BattistigThe microscopic structure and introduction rate of point defects in n-type 6H- and 4H-SiC generated by room-temperature proton implantation have been studied by the electron paramagnetic resonance technique. In order to selectively study the effects of defect introduction in the trace region, 12-MeV... (Read more)
- 181. Phys. Rev. B 61, 4659-4666 (2000) , “Identification of the Oxygen-Vacancy Defect Containing a Single Hydrogen Atom in Crystalline Silicon”, P. Johannesen, B. Bech Nielsen, J. R. Byberg.Float-zone and Czochralski-grown silicon crystals have been implanted with protons or deuterons at ?50 K. Electron paramagnetic resonance measurements reveal a new signal in the spectrum of the Czochralski-grown (oxygen-rich) material. This signal is strongly temperature dependent, displaying a... (Read more)
- 182. Phys. Rev. B 61, 2657 (2000) , “Divacancy-Tin Complexes in Electron-Irradiated Silicon Studied by EPR”, M. Fanciulli, J. R. Byberg.n- and p-type float-zone silicon containing 1018-cm-3 tin were irradiated with 2 MeV electrons to a dose of 1018 cm-2 and subsequently examined by electron paramagnetic resonance (EPR). The p-type material yields only the well-known Si-G29 signal due to... (Read more)
- 183. Phys. Rev. B 61, 13655 (2000) , “Intravacancy transition energies in 3C- and 4H-SiC”, A. Zywietz, J. Furthmüller, F. BechstedtSpin-polarized ab initio calculations are used to determine energy differences between ground and excited states of silicon and carbon vacancies in 3C- and 4H-SiC. The calculated transition energies are compared with recent findings from photoluminescence and magnetic-resonance experiments. (Read more)
- 184. Phys. Rev. B 61, 12602 (2000) , “Phosphorus-related deep donor in SiC”, A. Gali, P. Deák, P. R. Briddon, R. P. Devaty, W. J. ChoykeTwo phosphorus centers in SiC, an isolated P atom substituting for Si (PSi) and a Si-site P-atom adjacent to a carbon vacancy (PSi+VC) are investigated by first principle calculations. It is shown that PSi+VC produces a singly occupied donor... (Read more)
- 185. Mater. Sci. Eng. B 61-62, 202 (1999) , “Carbon-vacancy related defects in 4H- and 6H-SiC”, N. T. Son, W. M. Chen, J. L. Lindström, B. Monemar, E. JanzénElectron paramagnetic resonance (EPR) was used to study intrinsic defects in 4H- and 6H-SiC irradiated with 2.5 MeV electrons with doses ranging from 1×1017 to 2×1018 cm−2. In p-type 4H- and 6H-SiC, the dominant EPR signal, labeled EI1, associates with a defect centre having a low... (Read more)
- 186. Phys. Rev. B 59, 15166 (1999) , “Vacancies in SiC: Influence of Jahn-Teller distortions, spin effects, and crystal structure”, A. Zywietz, J. Furthmüller, and F. BechstedtWe present results of first-principles calculations for the neutral and charged Si and C monovacancies in cubic (3C) and hexagonal (4H) SiC. The calculations are based on the density functional theory in the local-density approximation as well as local spin density approximation. Explicitly a... (Read more)
- 187. Phys. Rev. B 59, 12900 (1999) , “Electron-paramagnetic-resonance measurements on the divacancy defect center R4/W6 in diamond”, D. J. Twitchen, M. E. Newton, J. M. Baker, T. R. Anthony, W. F. BanholzerElectron-paramagnetic-resonance (EPR) studies in radiation damaged diamond enriched to 5% 13C have resulted in the identification of the nearest-neighbor divacancy center. It is the isotopic enrichment, and consequent observation of 13C hyperfine lines, that has permitted the... (Read more)
- 188. Phys. Rev. B 59, 10823-10829 (1999) , “Defect energy levels in electron-irradiated and deuterium-implanted 6H silicon carbide”, M. O. Aboelfotoh, J. P. DoyleUsing deep-level transient spectroscopy, we studied defect energy levels and their annealing behavior in nitrogen-doped 6H-SiC epitaxial layers irradiated with 2-MeV electrons and implanted with 300-KeV deuterium or hydrogen at room temperature. Five levels located at Ec-0.34,... (Read more)
- 189. Phys. Rev. B 59, 10603 (1999) , “Defect characterization in electron-irradiated 6H-SiC by positron annihilation”, A. Polity, S. Huth, M. LausmannIsochronal annealing investigations in electron-irradiated 6H-SiC were correlated with temperature-dependent measurements of positron lifetime. It turned out that the positron trapping at temperatures up to 300 K was dominated by the trapping in shallow positron traps. These defects were already... (Read more)
- 190. Phys. Rev. Lett. 83, 372 (1999) , “Hydrogen Electrochemistry and Stress-Induced Leakage Current in Silica”, Peter E. Blöchl and James H. StathisHydrogen-related defects in oxygen-deficient silica, representing the material of a thermal gate oxide, are analyzed using first-principles calculations. Energetics and charge-state levels of oxygen vacancies, hydrogen, and their complexes in the silica framework are mapped out. The neutral hydrogen... (Read more)
- 191. phys. stat. sol. (b) 210, 13 (1999) , “Neutral Vacancies in Group-IV Semiconductors”, A. Zywietz, J. Furthmüller, F. BechstedtAb initio plane-wave-supercell calculations are performed for the neutral monovacancies in silicon, silicon carbide and diamond using ultrasoft non-normconserving Vanderbilt pseudopotentials. We study the structure, the energetics and the single-particle energy spectrum. The local symmetry, the... (Read more)
- 192. Semicond. Sci. Technol. 14, 1141 (1999) , “Optically detected magnetic resonance studies of intrinsic defects in 6H-SiC”, N. T. Son, P. N. Hai, Mt. Wagner, W. M. Chen, A. Ellison, C. Hallin, B. Monemar, E. Janzén
- 193. Appl. Phys. A 67, 209 (1998) , “Silicon vacancies in 3C-SiC observed by positron lifetime and electron spin resonance”, A. Kawasuso, H. Itoh, N. Morishita, M. Yoshikawa, T. Ohshima, I. Nashiyama, S. Okada, H. Okumura, S. YoshidaPositron lifetime and electron spin resonance (ESR) measurements were performed for 1-MeV electronirradiated cubic silicon carbide (3C-SiC). From a comparison of the annealing behaviors of positron lifetime and ESR signal, we identified the annihilation of positrons localized at single-negative silicon vacancies. The positron lifetime at silicon vacancies was first determined experimentally to be 188|±|4 ps. This value agrees well with the theoretical positron lifetime for silicon vacancies [G. Brauer et al. Phys. Rev. B 54, 2512 (1996)]. The trapping coefficient of singlenegative silicon vacancies was also derived. (Read more)
- 194. J. Non-Cryst. Solids 239, 16-48 (1998) , “Optically active oxygen-deficiency-related centers in amorphous silicon dioxide”, Linards SkujaThe spectroscopic properties, structure and interconversions of optically active oxygen-deficiency-related point defects in vitreous silica are reviewed. These defects, the E′-centers (oxygen vacancies with a trapped hole or 3-fold-coordinated silicons), different variants of diamagnetic... (Read more)GeO2 SiO2| EPR PL gamma-irradiation optical-spectroscopy| 0.5-1.0eV 1.0eV~ 1H 2.0eV~ 3.0eV~ 4.0eV~ 5.0eV~(larger) Chlorine E' E'-alpha E'-betha E'-delta E'-gamma Germanium H(I) H(II) Hydrogen ODC ODC(I) ODC(II) OHC Oxygen POR Silicon amorphous dangling-bond dielectric interstitial pair(=2) surface triplet vacancy | last update: Takahide Umeda
- 195. Phys. Rev. B 57, 1607 (1998) , “Electronic structure of the deep boron acceptor in boron-doped 6H-SiC”, A. v. Duijn-Arnold, T. Ikoma, O. G. Poluektov, P. G. Baranov, E. N. Mokhov, J. SchmidtA high-frequency (95 GHz) and conventional-frequency (9.3 GHz) pulsed electron paramagnetic resonance and electron-nuclear double resonance (ENDOR) study is reported on the deep boron acceptor in 6H-SiC. The results support a model in which the deep boron acceptor consists of a boron on a silicon... (Read more)
- 196. Phys. Rev. Lett. 80, 317-320 (1998) , “Experimental Evidence for Frenkel Defect Formation in Amorphous SiO2 by Electronic Excitation”, H. Hosono, H. Kawazoe, N. MatsunamiConcentrations of defects in amorphous SiO2 created by implantation of 10 MeV protons were examined. The depth profile of Si-Si bonds, E? centers, or peroxy radicals (PORs) was close to that of electronic energy loss. Interstitial O2 molecules were identified and... (Read more)
- 197. phys. stat. sol. (b) 210, 13 (1998) , “Neutral Vacancies in Group-IV Semiconductors”, A. Zywietz, J. Furthmüller, F. BechstedtAb initio plane-wave-supercell calculations are performed for the neutral monovacancies in silicon, silicon carbide and diamond using ultrasoft non-normconserving Vanderbilt pseudopotentials. We study the structure, the energetics and the single-particle energy spectrum. The local symmetry, the... (Read more)
- 198. Phys. Rev. B 56, 7384 (1997) , “Negatively charged Si vacancy in 4H SiC: A comparison between theory and experiment”, T. Wimbauer, B. K. Meyer, A. Hofstaetter, A. Scharmann, H. OverhofWe use electron paramagnetic resonance and electron nuclear double resonance to identify the negatively charged Si vacancy in neutron-irradiated 4H SiC. The identification is based on resolved ligand hyperfine interactions with carbon and silicon nearest and next nearest neighbors and on the... (Read more)
- 199. Phys. Rev. B 55, 2863 (1997) , “Optically detected magnetic resonance studies of defects in electron-irradiated 3C SiC layers”, N. T. Son, E. Sörman, W. M. Chen, C. Hallin, O. Kordina, B. Monemar, and E. JanzénDefects in electron-irradiated 3C SiC were studied by optically detected magnetic resonance (ODMR). In addition to the isotropic L2 center previously reported, an ODMR spectrum labeled L3, with a trigonal symmetry and an effective electron spin S=1, was observed after annealing at ?750 °C. The g... (Read more)
- 200. Phys. Rev. Lett. 79, 1507 (1997) , “Identification of the Silicon Vacancy Containing a Single Hydrogen Atom by EPR”, B. Bech Nielsen, P. Johannesen, P. Stallinga, K. Bonde Nielsen
- 201. Appl. Phys. Lett. 68, 403 (1996) , “Correlation between photoluminescence and oxygen vacancies in ZnO phosphors”, K. Vanheusden, C. H. Seager, W. L. Warren, D. R. Tallant, and J. A. VoigtBy combining electron paramagnetic resonance (EPR), optical absorption, and photoluminescence (PL) spectroscopy, a strong correlation is observed between the green 510 nm emission, the free-carrier concentration, and the density of singly ionized oxygen vacancies in commercial ZnO phosphor powders.... (Read more)
- 202. J. Appl. Phys. 79, 7983-7990 (1996) , “Mechanisms behind green photoluminescence in ZnO phosphor powders”, K. Vanheusden, W. L. Warren, C. H. Seager, D. R. Tallant, J. A. Voigt, B. E. GnadeWe explore the interrelationships between the green 510 nm emission, the free-carrier concentration, and the paramagnetic oxygen-vacancy density in commercial ZnO phosphors by combining photoluminescence, optical-absorption, and electron-paramagnetic-resonance spectroscopies. We find that the green... (Read more)
- 203. Appl. Phys. Lett. 67, 1280 (1995) , “Impact of Pb doping on the optical and electronic properties of ZnO powders”, K. Vanheusden, W. L. Warren, J. A. Voigt, C. H. Seager, and D. R. TallantElectron paramagnetic resonance (EPR), optical absorption, and photoluminescence (PL) spectroscopy have been combined to characterize Pb-doped ZnO ceramic powders. We observe a decrease in the 2.26 eV emission peak and a concomitant smearing of the band edges, narrowing the effective gap of the... (Read more)
- 204. J. Appl. Phys. 77, 837 (1995) , “Photoluminescence of radiation induced defects in 3C-SiC epitaxially grown on Si”, Hisayoshi Itoh, Masahito Yoshikawa, Isamu Nashiyama, Hajime Okumura, Shunji Misawa, Sadafumi YoshidaPhotoluminescence (PL) has been used to study defects introduced by 1-MeV-electron irradiation in cubic silicon carbide (3C-SiC) films epitaxially grown on Si substrates by means of chemical vapor deposition. A dominant PL line of 1.913 eV observed in 3C-SiC irradiated with electrons was found to... (Read more)
- 205. Phys. Rev. B 51, 1928 (1995) , “Carbon and silicon vacancies in electron-irradiated 6H-SiC”, S. Dannefaer, D. Craigen, D. KerrPositron-lifetime and Doppler-broadening spectroscopies were used to investigate vacancies formed by 2.2- and 10-MeV electrons. Carbon vacancies yield a positron lifetime of 160 ps, only 15 ps longer than the bulk lifetime, and the Doppler-broadening S parameter is very close to that for the bulk.... (Read more)
- 206. J. Non-Cryst. Solids 179, 1-9 (1994) , “The many varieties of E′ centers: a review”, Robert A. WeeksThree varieties of E′ centers with a spin state, S = 1/2, and with a G-tensor, Gx Gy 2.0003, Gz 2.0018, were identified in the early reports on paramagnetic states in irradiated α-quartz. The atomic structure of two of these had an hydrogen ion (proton) in nearby sites and hence... (Read more)
- 207. Proc. symp. on the degradation od electronic devices due to device operation as well as crystalline and process-induced defects 94-1, 221-234 (1994) , ECS (ISBN:1-56677-037-8) , “Spin dependent recombination in Si p-n junctions”, B. K. Meyer , P. Christmann , W. Stadler, H. Overhof, J.-M. Spaeth, S. Greulich-Weber, B. Stich
- 208. Phys. Rev. B 46, 12335 (1992) , “Microscopic mechanism of atomic diffusion in Si under pressure ”, Osamu Sugino and Atsushi OshiyamaWe have performed the first-principles total-energy calculations on the atomic diffusion of group-V impurities in Si, and have revealed the pressure effect on the activation energy of the diffusion. For the vacancy mechanism, the activation energies for P, As, and Sb decrease with pressure. For the... (Read more)
- 209. Phys. Rev. Lett. 67, 2517 (1991) , “Experimental evidence for excitonic mechanism of defect generation in high-purity silica”, T. E. Tsai and D. L. GriscomDirect evidence for the creation of oxygen-vacancy, oxygen-interstitial pairs in SiO2 glasses by an excitonic mechanism is developed from an electron-spin-resonance study of high-purity fused silicas exposed to highly focused 6.4-eV excimer laser light. (Read more)
- 210. Physica B 170, 155-167 (1991) , “Electron paramagnetic resonance of hydrogen in silicon ”, Yu.V. Gorelkinskii, N.N. Nevinnyi
- 211. J. Appl. Phys. 66, 4529 (1989) , “Electron spin resonance in electron-irradiated 3C-SiC”, Hisayoshi Itoh, Naohiro Hayakawa, Isamu Nashiyama, Eiichiro SakumaElectron-irradiation-induced defects in epitaxially grown 3C-SiC crystals have been studied by electron-spin-resonance (ESR) measurements. The results indicate the presence of an isotropic ESR center that consists of five lines equally spaced at about 1.5 G and has a g value of... (Read more)
- 212. Phys. Rev. B 38, 3395-3399 (1988) , “Electrical and Optical Properties of Defects in Silicon Introduced by High-Temperature Electron Irradiation”, Jian-Guo Xu, Fang Lu, and Heng-Hui Sun2-MeV electron irradiation of Si at elevated temperature creates a dominant deep level at the energy Ec-0.36 eV in addition to the oxygen vacancies. This level, which is less significant in room-temperature-irradiated Si, is found to be an efficient recombination center in the present... (Read more)
- 213. Phys. Rev. B 38, 12752(R) (1988) , “Formation energies, abundances, and the electronic structure of native defects in cubic SiC”, C. Wang, J. Bernholc, R. F. DavisThe relative abundance of native point defects in cubic SiC has been studied via ab initio calculations as a function of composition and the Fermi-level position. For Si-rich cubic SiC, the SiC antisite is the dominant defect in n-type material, while the carbon vacancy, which is a double... (Read more)
- 214. Phys. Lett. A 125, 354 (1987) , “EPR Evidence of Helium-Oxygen-Vacancy Complexes in Crystalline Silicon”, Yu. V. Gorelkinskii, N. N. Nevinnyi and S. S. AjazbaevTwo new (S = 1) EPR spectra, labeled Si-AA7 and Si-AA8, arise from a helium-associated defect in crystalline silicon. Both are produced only in Czochralski-grown silicon by helium ion implantation at ≈ 20°C followed by annealing at ≈ 180°C and are stable to ≈... (Read more)Si| EPR| AA10 AA7 AA8 Helium vacancy .inp files: Si/V-He-O2 Si/AA10 Si/V-He-O1 | last update: Takeo Kitamura
- 215. Phys. Rev. B 35, 1582 (1987) , “Electronic and Atomic Structure of the Boron-Vacancy Complex in Silicon”, M. Sprenger, R. van Kemp, E. G. Sieverts, and C. A. J. AmmerlaanIn electron-irradiated boron-doped silicon the electron paramagnetic resonance spectrum Si-G10 has been studied. Earlier this spectrum had tentatively been identified with a boron-vacancy complex in a next-nearest-neighbor configuration. With electron-nuclear double resonance the hyperfine and... (Read more)
- 216. Solid State Commun. 61, 199-202 (1987) , “An EPR study on a new triclinic symmetry defect in neutron-irradiated FZ-silicon”, Wu En, Wu Shu-xian, Mao Jin-Chang, Yan Mao-Xun, Qin Guo-gang
- 217. Phys. Lett. A 110, 157 (1985) , “EPR of Neutral Vacancy-Helium Centers in Silicon”, Yu. V. Gorelkinskii, N. N. Nevinnyi and S. S. AjazbaevIn this letter we report the first observation by EPR of helium-associated defects in solid. Two new (S = 1) EPR spectra, labeled Si-AA5 and Si-AA6, arise from the association of helium and intrinsic defects in crystalline silicon. Both are produced by helium ion implantation at room temperature and... (Read more)
- 218. phys. stat. sol. (a) 92, K53 (1985) , “Low Symmetry Centre in Silicon”, A. V. Dvurechenskii, V. V. Suprunchik.Investigation of the defect formation in heavily doped silicon irradiated by high dose of electrons have led to the discovery of new types of defects /1, 2/. The present note is the next one of this series. A new centre is investigated in p-type silicon irradiated by neutrons. (Read more)Si| EPR neutron-irradiation| A5 C1 H8 P3 P6 Sii Vsi interstitial p-type triclinic vacancy .inp files: Si/H8/H8.inp | last update: Takahide Umeda
- 219. phys. stat. sol. (a) 86, 313 (1984) , “New EPR Defects in Si<Al>”, A. V. Dvurechenskii, B. P. Kashnikov, V. V. Suprunchik.Two new paramagnetic centres, labeled Si-H5 and Si-H6 are found in silicon containing aluminium (6 × 1017 to 5 × 1018 cm-3) and irradiated with high dose of 1 Me V electrons (up to 2 × 1020 cm-2). Spin-Hamiltonian constants of the Si-H5... (Read more)
- 220. J. Appl. Phys. 54, 179-183 (1983) , “The Mechanism of the Enhancement of Divacancy Production by Oxygen During Electron Irradiation of Silicon. II. Computer Modeling”, G. S. Oehrlein, I. Krafcsik, J. L. Lindström, A. E. Jaworowski, and J. W. CorbettNumerical tests of possible models for the oxygen dependence of the divacancy introduction rate in silicon electron irradiated at room temperature were performed on a computer. Only the model in which oxygen traps Si self-interstitials can reproduce all the experimental data. Our modeling results... (Read more)
- 221. Phys. Lett. A 99, 117 (1983) , “Low-Symmetry EPR Center in Hydrogen-Implanted Silicon”, Yu.V. Gorelkinskii, N.N. NevinnyiA new S = 1/2 EPR spectrum, labeled Si-AA2, arises from a negative-charge-state defect which has a low symmetry(C1). It is produced in crystalline silicon by hydrogen implantation at ≈20°C followed by annealing at ≈580°C and disappears completely at 700°C. The kinetics... (Read more)Si| EPR ion-implantation| 29Si AA2 C1 Hydrogen Si-H Vsi cluster(>3) p-type triclinic vacancy .inp files: Si/AA2/AA2.inp | last update: Takahide Umeda
- 222. Phys. Rev. Lett. 51, 423 (1983) , “Creation of Quasistable Lattice Defects by Electronic Excitation in SiO2”, Katsumi Tanimura, Takeshi Tanaka, and Noriaki ItohThe transient volume change of ?-quartz and fused silica induced by irradiation with an electron pulse has been measured above 80 K. It is shown that transient changes of volume and optical absorption due to the E1? centers (oxygen vacancies) decay in parallel and that the... (Read more)
- 223. Solid State Commun. 43, 41 (1982) , “The Neutral Divacancy in Silicon”, E. G. Sieverts, J. W. Corbett.Extended Hückel Theory calculations have been carried out on a cluster of silicon atoms to examine the relative stability of two configurations of the divacancy: (1) two vacancies on adjacent sites, i.e. the "normal" divacancy configuration; and (2) two vacancies separated by two... (Read more)
- 224. Sov. Phys. Solid State 23, 2126 (1981) , “Electron spin resonance of exchange-coupled vacancy pairs in hexagonal silicon carbide”, V. S. Va?ner, V. A. ll’in
- 225. J. Vac. Sci. Technol. 15, 1298-1310 (1978) , “Reactions of oxygen with ZnO–100-surfaces”, W. GöpelInvestigations are reported on the reaction of oxygen with electrostatic neutral ZnO100-surfaces studied by means of AES, LEED, EPR, thermal desorption spectroscopy, and isotopic exchange as well as changes in the surface conductivity and work function. Geometric and electronic structures of... (Read more)
- 226. Solid State Commun. 28, 221 (1978) , “On the Production of Paramagnetic Defects in Silicon by Electron Irradiation”, E. G. Sieverts, S. H. Muller and C. A. J. AmmerlaanMonocrystalline silicon samples of different impurity contents have been irradiated with 1.5 MeV electrons in order to produce divacancies in their negative charge state. In these samples different combinations of defects have been observed with electron paramagnetic resonance. The conditions for... (Read more)
- 227. Phys. Lett. A 60, 55 (1977) , “Oxygen-vibrational bands in irradiated silicon*1”, Y. H. Lee, J. C. Corelli, J. W. Corbett.A correlation is made between the EPR spectra and the IR absorption bands for the known multivacancy-oxygen complexes in irradiated silicon. (Read more)
- 228. Appl. Phys. Lett. 29, 265 (1976) , “EPR Evidence for a Positively Charged Vacancy-Oxygen Defect in Silicon”, Paul R. BrosiousA new EPR spectrum, labeled Si-I3, has been observed in electron-irradiated n-type Czochralski silicon illuminated with approximately band-gap light. The g-tensor symmetry, the g shifts from the free-electron value, and the temperature dependence of the spectrum amplitude lead to the... (Read more)
- 229. Phys. Rev. B 13, 2653 (1976) , “EPR Studies of Defects in Electron-Irradiated Silicon: A Triplet State of Vacancy-Oxygen Complexes”, Young-Hoon Lee and James W. CorbettThree new EPR spectra (Si-A 14, -A 15, and -A 16) and two previously known spectra (Si-P2 and -P4) are observed for the first time in electron-irradiated silicon. The microscopic defect models are established as multivacancy-oxygen complexes with the oxygen(s) in Si-O-Si structure inside the ... (Read more)
- 230. Phys. Rev. B 13, 2511 (1976) , “EPR of a Trapped Vacancy in Boron-Doped Silicon”, G. D. Watkins.An S=1/2 EPR spectrum, labeled Si-G10, is tentatively identified as a lattice vacancy trapped by substitutional boron in silicon. It is produced in boron-doped vacuum floating-zone silicon by 1.5-MeV-electron irradiation at 20.4 K followed by an anneal at ? 180 K, where the isolated vacancy... (Read more)
- 231. Z. Physik B 23, 171-181 (1976) , “Intrinsic Defects in Electron Irradiated Zinc Oxide”, B. Schallenberge, A. Hausmann
- 232. Lattice Defects in Semiconductors 23, 1-22 (1975) , Institute of Physics, London , “EPR Studies of the Lattice Vacancy and Low-Temperature Damage Processes in Silocon”, G. D. Watkins.EPR studies of silicon irradiated at 20.4 K and 4.2 K by 1.5 MeV and 46 MeV electrons are described. In 46 MeV irradiations the dominant defects formed appear to be divavancies and other multiple defect aggregates which liberate vacancies throughout the anneal to room temperature as they reorder, recombine, etc. For 1.5 MeV irradiations group III atoms play a vital role in p- and n-type materials in trapping interstitials and stabilizing damage. Carbon and oxygen are not effective interstitial traps at these temperatures. Evidence of limited vacancy migration during irradiation is also cited. Two distinct excited configurations of vacancy-oxygen pairs are identified as precursors to A-centre formation in n-type silicon. The kinetics for their conversion to A-centres depends strongly upon the Fermi level as does the isolated vacancy migration energy whhich is measured to be 0.18 ± 0.02 eV for the Vï¼ charge state. The vacancy has four charge states, V+, V0, Vï¼ and Vï¼. Kinetics for hole release from V+ reveals an activation barrier of 0.057 eV. The concentration of V+ at 20.4 K in boron-doped material indicates the corresponding donor level even closer to the band edge, approximately EV + 0.039 eV. Jahn-Teller energies for V0, V+, and Vï¼ are estimated from stress-alignment studies and confirmed to be large. Kinetics studies for reorientation from one Jahn-Teller distortion to another are also described for each charge state.
- 233. Phys. Rev. B 12, 4383 (1975) , “Defects in Irradiated Silicon: EPR of the Tin-Vacancy Pair”, G. D. Watkins.An EPR spectrum, labeled Si-G29, is identified as a lattice vacancy trapped by substitutional tin. The resulting tin-vacancy pair is observed in its neutral ground state with S=1. Studies versus wavelength of illumination indicate that it has a donor level at ?Ev+0.35 eV. Analysis of the... (Read more)
- 234. Solid State Commun. 16, 171 (1975) , “On the Role of Defect Charge State in the Stability of Point Defects in Silicon”, L. C. Kimerling, H. M. DeAngelis, J. W. Diebold.Defect annealing in 1-MeV electron-irradiated, phosphorus-doped silicon is studied. Charge state effects are explored directly using a p-n junction structure. A defect state which is associated with the E center (phosphorus-vacancy pair) is found to disappear at approximately 150°C with an... (Read more)
- 235. Phys. Rev. B 9, 4351-4361 (1974) , “EPR study of defects in neutron-irradiated silicon: Quenched-in alignment under <110>-uniaxial stress”, Young-Hoon Lee and James W. CorbettThe stress effect in an EPR study is first treated rigorously in terms of the piezospectroscopic tensor, taking account of the local symmetry of a defect. It is found that the degree of alignment (n?/n?) provides incisive information on the structure of a defect; in general, a... (Read more)
- 236. Solid State Commun. 14, 953-956 (1974) , “Temperature dependence of the ESR spectrum of the zinc vacancy in ZnO”, D. Galland and A. HerveThe temperature dependence of the spectrum of two trapped hole centers introduced by electron irradiation in ZnO is described. The results firmly establish the identification of these centers as being two slightly inequivalent configurations of the zinc vacancy in its negative charge state. (Read more)
- 237. Phys. Rev. B 8, 2810 (1973) , “EPR Studies in Neutron-Irradiated Silicon: A Negative Charge State of a Nonplanar Five-Vacancy Cluster (V5-)”, Y. H. Lee, J. W. Corbett.EPR studies are carried out for the float-zone intrinsic silicon irradiated with reactor neutrons up to the total fluence 1018 n/cm2. Details of the Si29 hyperfine structure and of the g tensor in the P-1 spectrum are observed with respect to temperature from 77 to... (Read more)Si| EPR neutron-irradiation| 29Si P1 Silicon cluster(>3) vacancy .inp files: Si/V5- | last update: Takahide Umeda
- 238. J. Appl. Phys. 43, 3499-3506 (1972) , “Electron Paramagnetic Resonance of the lattice Damage in Oxygen-Implanted Silicon”, K.L. Brower and Wendland BeezholdThe nature of the lattice damage produced at room temperature in ion-implanted intrinsic and n-type silicon has been studied as a function of 160-keV O+ ion fluence using electron paramagnetic resonance (EPR). The known EPR spectra observed were the negative divacancy (Si-G7), the... (Read more)Si| EPR ion-implantation neutron-irradiation| 31P D G7 Oxygen P3 Phosphorus S1 S2 SL2 Silicon amorphous vacancy .inp files: Si/SL2 | last update: Takahide Umeda
- 239. Phys. Rev. B 5, 4274 (1972) , “17O Hyperfine Structure of the Neutral (S=1) Vacancy-Oxygen Center in Ion-Implanted Silicon”, K. L. Brower.The intensity of the 17O hyperfine spectrum associated with the 28Si-17O-28Si isotopic configuration of the vacancy-oxygen (Si-S1) center was enhanced by ion implantation of 17O into silicon. The Si-S1 17O hyperfine spectrum was... (Read more)Si| EPR ion-implantation| 17O Oxygen SL1 pair(=2) vacancy .inp files: Si/V-O* | last update: Takahide Umeda
- 240. Phys. Rev. B 5, 3988 (1972) , “Electron-Paramagnetic-Resonance Detection of Optically Induced Divacancy Alignment in Silicon”, C. A. J. Ammerlaan, G. D. Watkins.An EPR study was made of the divacancy in silicon, produced by 1.5-MeV electron irradiation at room temperature, under illumination with polarized light. A light-induced alignment of divacancies among the various Jahn-Teller distortion directions in the lattice is observed for the singly positively... (Read more)
- 241. Radiat. Eff. 15, 77 (1972) , “New EPR Spectra in Neutron-Irradiated Silicon”, Y. H. Lee, Y. M. Kim, J. W. Corbett.Six new EPR spectra are reported which are apparently due to intrinsic defects created in the neutron-irradiation and, in some cases, annealing of silicon. In addition a spectrum similar to, but distinct from, that due to the vacancy-phosphorus center is reported. Some tentative defect models are discussed to emphasize the features of the spectra, but more detailed studies are required to establish the identity of the giving rise to these spectra.
- 242. Phys. Rev. B 4, 1968 (1971) , “Electron Paramagnetic Resonance of the Neutral (S=1) One-Vacancy-Oxygen Center in Irradiated Silicon”, K. L. Brower.A new EPR spectrum, labeled Si-S1, has been observed in electron- or neutron-irradiated, n- or p-type, crucible-grown silicon under illumination with approximately band-gap light. The Si-S1 spectrum consists primarily of a fine-structure spectrum and a 29Si hyperfine spectrum. By... (Read more)
- 243. Phys. Lett. A 33, 1-2 (1970) , “ESR spectra of the zinc vacancy in ZnO”, D. Galland and A. HerveElectron irradiated ZnO single crystals show anisotropic ESR spectra corresponding to a spin and a spin 1 hole centers. Tehy are respectively identified as the negative and the neutral charge states of the zinc vacancy. (Read more)
- 244. Solid State Commun. 8, 1359-1361 (1970) , “Electron paramagnetic resonance associated with Zn vacancies in neutron-irradiated ZnO”, A. L. Taylor, G. Filipovich and G. K. LindebergLines in the EPR spectrum of ZnO crystals irradiated by 3.6 × 1018cm−2 fast neutrons are ascribed to holes on oxygen atoms in the basal plane of O4 tetrahedra which surround Zn vacancies. (Read more)
- 245. Phys. Rev. 174, 881 (1968) , “Defects in Irradiated Silicon: Electron Paramagnetic Resonance and Electron-Nuclear Double Resonance of the Arsenic- and Antimony-Vacancy Pairs”, Edward L. Elkin and G. D. WatkinsTwo EPR spectra are observed in irradiated silicon (designated Si-G23 and Si-G24) which are identified with the neutral charge states of a lattice vacancy adjacent to a substitutional arsenic or antimony atom, respectively. EPR and ENDOR studies reveal a high degree of similarity between these... (Read more)
- 246. Phys. Rev. 155, 802 (1967) , “Defects in Irradiated Silicon: Electron Paramagnetic Resonance and Electron-Nuclear Double Resonance of the Aluminum-Vacancy Pair”, G. D. Watkins.An EPR spectrum produced in aluminum-doped silicon by 1.5-MeV electron irradiation is described. Labeled Si G9, it is identified as arising from an aluminum-vacancy pair, presumably formed when a mobile lattice vacancy is trapped by substitutional aluminum. The resonance is observed only upon... (Read more)
- 247. Phys. Rev. 138, A555 (1965) , “Production of Divacancies and Vacancies by Electron Irradiation of Silicon”, J. W. Corbett and G. D. WatkinsA study is described of the dependence of the room-temperature production of divacancies and vacancies in silicon upon the energy of the bombarding electrons over the range 0.7-56 MeV. For the divacancy, the Si-G6 electron-paramagnetic-resonance spectrum associated with the singly positively charged... (Read more)
- 248. Phys. Rev. 138, A543 (1965) , “Defects in Irradiated Silicon: Electron Paramagnetic Resonance of the Divacancy”, G. D. Watkins and J. W. CorbettTwo electron paramagnetic resonance spectra produced in silicon by 1.5-MeV electron irradiation are described. Labeled Si-G6 and Si-G7, they are identified as arising from the singly positive and singly negative charged states of the divacancy, respectively. The observed hyperfine interactions with... (Read more)
- 249. Radiation Damage in Semiconductors 97-113 (1965) , Dunod, Paris , “A Review of EPR Studies in Irradiated Silicon”, G. D. Watkins.1. INTRODUCTION (p.97): 2. THE EPR EXPERIMENT (p.97): 3. RESULTS (p.99): A. The lattice Vacancy (p.99), B. Vacancies Trapped by Other Defects (p.102), C. Vacancy Motion (p.103), D. Interstitial Defects (p.103), E. Other Spectra (p.105), 4. SUMMARY AND CONCLUSION (p.110): 5.ACKNOWLEDGMENTS (p.110):
- 250. Phys. Rev. 135, A1381-A1385 (1964) , “New Oxygen Infrared Bands in Annealed Irradiated Silicon”, J. W. Corbett, G. D. Watkins, and R. S. McDonaldInfrared and electron-spin-resonance measurements on the recovery of silicon irradiated with 1.5-MeV electrons are presented. In the infrared measurements the disappearance of the previously reported 829-cm-1 (12?) oxygen vibration band is followed, and the appearance and subsequent... (Read more)
- 251. Phys. Rev. 134, A1359 (1964) , “Defects in Irradiated Silicon: Electron Paramagnetic Resonance and Electron-Nuclear Double Resonance of the Si-E Center”, G. D. Watkins, J. W. Corbett.The Si-E center is one of the dominant defects produced by electron irradiation in phosphorus-doped vacuum floating zone silicon. It introduces an acceptor level at ?(Ec-0.4) eV and gives rise to an electron paramagnetic resonance when this level does not contain an electron. As a result... (Read more)
- 252. J. Phys. Soc. Jpn. sppl. II, 18, 22 (1963) , “An EPR Study of the Lattice Vacancy in Silicon”, G. D. Watkins.An EPR spectrum is observed in silicon which is identified as arising from the isolated lattice vacancy. It is observed in p-type silicon which has been irradiated in situ at~40ºK by 1.5 Mev electrons. A simple molecular orbital treatment of the vacancy is outlined which describes many of the features of the spectrum and predicts the observed anisotrophy as resulting from a Jahn-Teller distortion. Studies of the disappearance of the vacancy vs anneal are described and interpreted in terms of long range migration of the vacancy and subsequent trapping by other defects. The activation energy for vacancy motion is determined to be 0.33±.03 ev in p-type material. Further study is required in n-type silicon before an unambiguous interpretation of the emergence of vacancy-impurity pairs can be made.
- 253. Phys. Rev. 132, 648 (1963) , “Spin-1 Centers in Neutron-Irradiated Silicon”, Wun Jung and G. S. NewellElectron paramagnetic resonance was used to study a number of fast-neutron-induced defects formed in pile-irradiated silicon and to follow their concentrations as a function of annealing. Measurements were made at 300, 77, and 4.2°K on samples which had attained intrinsic resistivity during... (Read more)
- 254. Phys. Rev. 121, 1001 (1961) , “Defects in Irradiated Silicon. I. Electron Spin Resonance of the Si-A Center”, G. D. Watkins, J. W. Corbett.The Si-A center is a major, radiation-damage defect produced in "pulled" silicon by a room temperature irradiation. As a result of studies described in this paper (I), and the following one (II), it is concluded that this center is a lattice vacancy with an oxygen atom impurity bridging two of the... (Read more)
- 255. Phys. Rev. Lett. 7, 314 (1961) , “Silicon Divacancy and Its Direct Production by Electron Irradiation”, J. W. Corbett and G. D. WatkinsTo date two defects produced in radiation damage of silicon hava been identified.These defects are a vacancy-oxygeon pair and a vacancy-phosphorous pair. They were identified largely by their associated electron spin resonance spectra and have been labeled the Si-A and Si-E... (Read more)Si| EPR electron-irradiation| G6 Silicon pair(=2) vacancy .inp files: Si/V2+ | last update: Takashi Fukushima
- 256. J. Appl. Phys. 30, 1195 (1959) , “Paramagnetic Resonance in Electron Irradiated Silicon”, G. Bemski.Electron spin resonance has been observed in n-type silicon irradiated with 0.5-Mev electrons. The particular resonance lines discussed here appear only in pulled crystals which contain about 1018 oxygen atoms per cm3. The lines do not appear in floating zone crystals... (Read more)Si| EPR electron-irradiation| A Oxygen Silicon pair(=2) vacancy .inp files: Si/V-O | last update: Takahide Umeda
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