Positively charged carbon vacancy in 6H–SiC: EPR study
| Autor: | H. J. von Bardeleben, V.Ya. Bratus, I.N. Makeeva, S. M. Okulov, T.T. Petrenko, T.L. Petrenko |
|---|---|
| Rok vydání: | 2001 |
| Předmět: |
Materials science
Ab initio Condensed Matter Physics Crystallographic defect Electronic Optical and Magnetic Materials law.invention Crystal Crystallography Ab initio quantum chemistry methods law Vacancy defect Electrical and Electronic Engineering Spin (physics) Electron paramagnetic resonance Hyperfine structure |
| Zdroj: | Physica B: Condensed Matter. :621-624 |
| ISSN: | 0921-4526 |
| DOI: | 10.1016/s0921-4526(01)00755-4 |
| Popis: | The low-temperature X-band EPR study of Ky1 and Ky2 centers assigned to positively charged carbon vacancy (V + c ) 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 g-tensor are determined as g z = 2.0048, g x = 2.0022 and g y =2,0037 for Ky2 defect, where z- and x-directions reside in the ( 120) plane and the z-axis makes up an angle 65° with the c-axis. The same residence of z- and x-axis and an angle 59° are found for Kyl center with g z = 2.0058, g x =2.0025 and g y , = 2.0023. For Ky2 center, the principal values and corresponding directional cosines of the hyperfine (HF) interaction tensor A are determined for four Si atoms in the nearest neighborhood of the defect. Ky3 center is tentatively proposed as V + c defect in quasihexagonal site of 6H-SiC. The results of ab initio DFT calculations using cubic C 18 Si 16 H 36 and hexagonal C 18 Si 20 H 40 clusters corroborate the main features of proposed V + c defect models including the point symmetry and values of HF parameters. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect