Premium
Electronic structure of the nitrogen donors in 6H SiC as studied by pulsed ENDOR and TRIPLE ENDOR spectroscopy
Author(s) -
Savchenko Dariya V.,
Kalabukhova Ekateri.,
Pöppl Andreas,
Shanina Bela D.
Publication year - 2012
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.201248209
Subject(s) - electron paramagnetic resonance , atomic physics , spectroscopy , hyperfine structure , nitrogen , crystallography , lattice constant , resonance (particle physics) , electron , lattice (music) , chemistry , spectral line , materials science , molecular physics , nuclear magnetic resonance , physics , organic chemistry , quantum mechanics , astronomy , diffraction , acoustics , optics
The nitrogen (N) donors in 6H SiC were investigated by field sweep electron spin echo (FS ESE), pulsed electron nuclear double resonance (ENDOR) and pulsed General TRIPLE ENDOR spectroscopy. The 29 Si and 13 C superhyperfine (shf) lines observed in the FS ESE and ENDOR spectra of N in n‐type 6H SiC were assigned by pulsed General TRIPLE resonance spectroscopy to the specific carbon (C) and silicon (Si) atoms located in the environment of N donors residing at two quasi‐cubic lattice sites (N k1 , N k2 ) in 6H SiC. As a result, the largest value of the shf interaction was found with Si atoms for the N donors at the hexagonal (N h ) and quasi‐cubic site N k1 , while for N k2 the largest value of the shf interaction was found with C atoms. It gives us the argument to consider that N substitute different lattice sites in 6H SiC lattice. The relative signs of the shf interaction (shfi) constants for N k1 and N k2 with 29 Si and 13 C nuclei located in the nearest‐neighbor, next nearest‐neighbor, and outer shells are found from the TRIPLE ENDOR spectra to be positive for C atoms and negative for Si atoms. From the comparison of the experimentally obtained shfi constants with the theory, the electronic spin‐density distribution over the 29 Si and 13 C nuclei located in the nearest neighbor shells of N donors has been obtained taking into account the Kohn–Luttinger interference effect. The position of the conduction band minimum along the ML‐line was determined to be at k 0 z / k max = 0.2 ± 0.05.