Anharmonicity of the C-H stretch mode in SiC: Unambiguous identification of hydrogen-silicon vacancy defect

Using first principles calculations, the vibronic properties of hydrogen in a silicon vacancy (V-Si+H) are investigated in 3C-SiC. The calculations show that the neutral V-Si+H complex, which can bind an exciton, is stable only in lightly p-type SiC. This result is consistent with the experimental findings. The calculations are able to account well for the observed anharmonicity of the C-H stretch vibrations, up to the third harmonic, and for the isotope effects. (C) 2002 American Institute of Physics.