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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. 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)
- 3. 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)
- 4. 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)
- 5. 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)
- 6. Phys. Rev. Lett. 97, 227401 (2006) , “Optical Detection and Ionization of Donors in Specific Electronic and Nuclear Spin States”, A. Yang, M. Steger, D. Karaiskaj, M. L. W. Thewalt, M. Cardona, K. M. Itoh, H. Riemann, N. V. Abrosimov, M. F. Churbanov, A. V. Gusev, A. D. Bulanov, A. K. Kaliteevskii, O. N. Godisov, P. Becker, H.-J. Pohl, J. W. Ager III, and E. E. HallerWe resolve the remarkably sharp bound exciton transitions of highly enriched 28Si using a single-frequency laser and photoluminescence excitation spectroscopy, as well as photocurrent spectroscopy. Well-resolved doublets in the spectrum of the 31P donor reflect the hyperfine... (Read more)
- 7. 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)
- 8. 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)
- 9. Physica B 340-342, 903-907 (2003) , “Pulsed EPR studies of shallow donor impurities in SiC”, J. Isoya, T. Ohshima, N. Morishita, T. Kamiya, H. Itoh, S. YamasakiSpin-lattice relaxation time (T1) and phase memory time (TM) of shallow donors in 3C-, 4H- and 6H-SiC have been measured in time domain by using pulsed EPR technique. The temperature dependence of T1 suggests that the Orbach process should be frozen at relatively high temperatures. Shallow donors in SiC are promising in attaining a sufficiently long phase memory time at temperatures much higher than Si:P. (Read more)
- 10. 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)
- 11. Phys. Rev. B 58, 3842 (1998) , “Electron Paramagnetic Resonance Study of Hydrogen-Vacancy Defects in Crystalline Silicon”, P. Stallinga, P. Johannesen, S. Herstm, K. Bonde Nielsen, B. Bech Nielsen, J. R. Byberg.Electron paramagnetic resonance measurements on float-zone silicon implanted with protons at ?50 K followed by heating to room temperature have revealed two signals S1a and S1b belonging to the S1 group of signals. S1a and S1b both originate from defects... (Read more)
- 12. 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
- 13. IEEE Trans. Nucl. Sci. 37, 1650-1657 (1990) , “Spin dependent recombination: A 29Si hyperfine study of radiation-induced Pb centers at the Si/SiO2 interface”, M. A. Jupina , P. M. Lenahan
- 14. Phys. Rev. B 37, 7268 (1988) , “Electron-nuclear double resonance of titanium in silicon: 47Ti and 49Ti ENDOR”, D. A. van Wezep, C. A. J. AmmerlaanThe electron-nuclear double-resonance spectra of interstitial 47Ti+ and 49Ti+ in silicon have been measured at 4.2 K. Spin Hamiltonians for these systems were determined and had to include hyperfine contributions of the type S3I and... (Read more)
- 15. J. Phys. Chem. 88, 5255-5260 (1984) , “Dynamic Interchange among Three States of Phosphorus (4+) in ?-Quartz. 2.”, Y. Uchida, J. Isoya, J. A. WeilThe dynamic process due to electron jumping among three states with different sp hybrid directions in the quasitetrahedral P4+ center [PO4]0 in a-quartz has been investigated by 10-GHz electron paramagnetic resonance, over the temperature range 40 to 400 K. The relative populations (mole fractions ƒІ and ƒІІ) of the ground state P(І) and two degenerate thermally excited states P(ІІ) were determined from the measured EPR absorption line intensity ratios and from the line positions of the averaged state P(A), respectively, in the slow and fast kinetic regions. The temperature dependence of the mole fractions has been explained by considering vibrational sublevels in the potential well describing each state. The jump rate was also obtained, via EPR absorption line-width analysis based on the Bloch equations, in both the slow and the fast regions. The characteristic parameters of the dynamic process, Le., energy separation and vibrational sublevels of the ground and excited states, and barrier height between these, have been determined. (Read more)
- 16. J. Phys. Chem. 83, 3462-3467 (1979) , “Dynamic Interchange among Three States of Phousphorus 4+ in ?-Quartz”, Y. Uchida, J. Isoya, J. A. WeilDynamic averaging due to electron jumping among three states with different sp hybrid directions in the P4+ center [PO4]0 in α-quartz has been studied by single-crystal electron paramagnetic resonance. The spin-Hamiltonian matrices g and Aslp for low temperature (i.e., C140 K) spectra P(І) and P(â…¡) and for high temperature spectrum P(A) are reported. For each crystal site, the line positions of P(A) agree well with those derived from the matrices measured for the three states. i.e., with weighted averages including P(І) and the two symmetry-related P(â…¡) spectra. (Read more)
- 17. Z. Physik B 23, 171-181 (1976) , “Intrinsic Defects in Electron Irradiated Zinc Oxide”, B. Schallenberge, A. Hausmann
- 18. 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.
- 19. 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)
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