Shockley-Read-Hall recombination and trap levels in In0.53Ga0.47As point defects from first principles

We present charge state transition levels of 23 intrinsic defects and dopant substitutions in the compound III-V semiconductor ${\mathrm{In}}_{0.53}{\mathrm{Ga}}_{0.47}\mathrm{As}$, calculated with density functional theory. We also report the Shockley-Read-Hall (SRH) recombination rate and capture coefficients for defects found to have deep trap levels. Our calculations show that seven of the considered defects exhibited deep trap levels capable of acting as electron and hole traps in devices: the ${\mathrm{As}}_{\text{In/Ga}}$ antisites, the ${\mathrm{V}}_{\text{In/Ga}}$ vacancies, the ${(\text{In/Ga})}_{\text{As}}\text{\ensuremath{-}}{\mathrm{As}}_{\text{In/Ga}}$ double antisites, and the ${\mathrm{Sn}}_{\text{As}}$ substitution. We found that the ${\mathrm{As}}_{\text{In}}$ antisite exhibits the highest electron-capture coefficient of ${C}_{n}=2.2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}\phantom{\rule{0.28em}{0ex}}{\mathrm{cm}}^{3}\phantom{\rule{0.16em}{0ex}}{\mathrm{s}}^{\ensuremath{-}1}$ at room temperature. The defect with the highest hole-capture coefficient was found to be the ${\mathrm{In}}_{\text{As}}\text{\ensuremath{-}}{\mathrm{As}}_{\text{In}}$ double antisite, with ${C}_{p}=3.4\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}\phantom{\rule{0.28em}{0ex}}{\mathrm{cm}}^{3}\phantom{\rule{0.16em}{0ex}}{\mathrm{s}}^{\ensuremath{-}1}$. Furthermore, this defect also causes the highest recombination rate in the intrinsic semiconductor, owing to its likewise relatively large electron-capture coefficient. The defects which are most likely to occur are argued to be the antisites, due to their low formation energies and matching transition levels with experiments. Additionally, it is found that the ${\mathrm{Sn}}_{\text{As}}$ substitution also causes a significant recombination in the semiconductor, but it is argued to only be of importance at very high doping levels.