Substitutional defect pairs in GaAs1-xPx

A theory of paired substitutional sp3-bonded defects in zincblende hosts is presented and successfully applied to the (spectator, oxygen) paris (Zn, O) and (VGa,O) in GaAs1-xPx and to (Mg, O), (Cd, O), (Zn, O), (VGa,O), and (Si, O) in GaP. Spectator impurities, when paired with isolated oxygen, may alter the oxygen binding energy or even drive its deep A1 level out of the band gap. © 1980 The American Physical Society.