« Previous
1
Next »
(75 hits, 1/1)
Showing
10, 25, 50, 100, 500, 1000, all papers per page.
Sort by:
last publication date,
older publication date,
last update date.
- 1. 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)
- 2. 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)
- 3. 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)
- 4. 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)
- 5. 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)
- 6. 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)
- 7. 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)
- 8. 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)
- 9. 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)
- 10. 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)
- 11. 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)
- 12. 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)
- 13. 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)
- 14. 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)
- 15. 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)
- 16. 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)
- 17. 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)
- 18. 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)
- 19. 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)
- 20. 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)
- 21. 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)
- 22. 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)
- 23. 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)
- 24. 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)
- 25. 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)
- 26. 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)
- 27. 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)
- 28. 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)
- 29. 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)
- 30. 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)
- 31. 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)
- 32. 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)
- 33. 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)
- 34. 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)
- 35. 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)
- 36. 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)
- 37. 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)
- 38. 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)
- 39. 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)
- 40. 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)
- 41. 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)
- 42. 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)
- 43. 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)
- 44. 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)
- 45. 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)
- 46. 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)
- 47. 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)
- 48. 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)
- 49. 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)
- 50. 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)
- 51. 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)
- 52. 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
- 53. 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)
- 54. 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)
- 55. 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)
- 56. 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)
- 57. 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)
- 58. 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)
- 59. 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)
- 60. 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)
- 61. 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)
- 62. 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)
- 63. 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)
- 64. 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)
- 65. 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)
- 66. 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)
- 67. Z. Physik B 23, 171-181 (1976) , “Intrinsic Defects in Electron Irradiated Zinc Oxide”, B. Schallenberge, A. Hausmann
- 68. 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.
- 69. 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
- 70. 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
- 71. 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)
- 72. 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):
- 73. 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)
- 74. 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)
- 75. 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
« Previous
1
Next »
(75 hits, 1/1)
Showing
10, 25, 50, 100, 500, 1000, all papers per page.
Sort by:
last publication date,
older publication date,
last update date.
All papers (3399)
Updated at 2010-07-20 16:50:39
Updated at 2010-07-20 16:50:39
(view as: tree
,
cloud
)
1329 | untagged |
Materials
(111 tags)
Others(101 tags)
Technique
(46 tags)
Details
(591 tags)
Bond(35 tags)
Defect(interstitial)(18 tags)
Defect(vacancy)(15 tags)
Defect-type(19 tags)
Element(65 tags)
Energy(8 tags)
Isotope(56 tags)
Label(303 tags)
Sample(17 tags)
Spin(8 tags)
Symmetry(15 tags)