Metastable defect complexes in GaAs

Metastability of the boron-vacancy complex in silicon: Insights from hybrid functional calculations

Using four distinct configurations of the boron-vacancy (BV) complex in silicon, we investigate the experimentally observed defect metastability of the BV complex in silicon using the HSE06 hybrid functional within the density functional theory formalism. We identify the experimentally observed metastable configurations of the defect complex when the substitutional boron is in the nearest neighbor position with respect to silicon vacancy and when the two defects are in the next (second) nearest neighbor position with respect to each other. The next (second) nearest neighbor position consists of two configurations that almost degenerate with C1 and C1h symmetry.

Identification of the carbon antisite-vacancy pair in 4H-SiC

The metastability of vacancies was theoretically predicted for several compound semiconductors alongside their transformation into the antisite-vacancy pair counterpart; however, no experiment to date has unambiguously confirmed the existence of antisite-vacancy pairs. Using electron paramagnetic resonance and first principles calculations we identify the S15 center as the carbon antisite-vacancy pair in the negative charge state (C(Si)V-(C)) in 4H-SiC. We suggest that this defect is a strong carrier-compensating center in n-type or high-purity semi-insulating SiC.