Papers by Keyword: ENDOR

Abstract: We show that electrically detected electron nuclear double resonance (EDENDOR) can be detected with relatively high signal-to-noise ratios in fully processed 4H-SiC bipolar junction transistors (BJTs). We observe EDENDOR of nitrogen interacting with recombination center defects in the depletion region of forward-biased emitter-base junctions of these devices at room temperature. Our results indicate that EDENDOR has great potential in the investigation of SiC-based devices specifically, as well as in the investigation of solid-state devices based upon other material systems.

Abstract: The nitrogen donors residing at quasi-cubic lattice site (N_k) in 4H SiC were investigated by field sweep electron spin echo (FS ESE), pulsed electron nuclear double resonance (ENDOR) and pulsed General TRIPLE ENDOR spectroscopy. The ²⁹Si and ¹³C superhyperfine lines observed in the FS ESE and ENDOR spectra of N_k 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 nearest environment of N_k in 4H SiC. The superhyperfine interaction constants and their relative signs for Nk with ²⁹Si and ¹³C nuclei located in the nearest-neighbor shells are found from the General TRIPLE ENDOR spectra to be positive for C atoms and negative for Si atoms.

Abstract: In EPR (electron paramagnetic resonance) identification of point defects, hyperfine (HF) interaction is decisive information not only for chemical identity but also for the local geometry and the electronic state. In some intrinsic defects in SiC, the wave function of the unpaired electron extends quite unevenly among major atoms comprising the defects. In such a case, the determination of the number of equivalent atoms and the chemical identity (Si or C) of those atoms even with weak HF splitting are useful to compare with HF parameters obtained theoretically. For vacancy-related defects of relatively deep levels, the sum of the spin densities on the nearest-neighbor shell is found to be 60-68%.