Electron parametric resonance identification of the SbGa heteroantisite defect in GaAs:Sb

GaAs doped with antimony (Sb) to a level of 10 high 19 cm high minus 3 has been studied by electron paramagnetic resoncance (EPR). A new EPR spectrum has been discovered which is identified as the Sb sub Ga heteroantisite defect. The electronic structure of this defect is practically indentical whith that of the intrinsic-anion antisite devects in GaP, GaAs, and InP. The EPR results show that Sb can be incorporated as an electrically active defect and therefore is not a suitable isovalent dopant in the growth of low-dislocation-density semi-insulating GaAs.