AsGa antisite defects in LT GaAs as studied by magnetic resonance and magneto-optical techniques.

GaAs epitaxial layers grown by molecular beam epitaxy (MBE) at low temperature (LT) have been characterized by electron spin resonance (ESR) infrared absorption, magnetic circular dichroism (MCD) and optically detected magnetic resonance (ODMR) via MCD . The data prove that AssubGa antisite defects contribute to the below-gap infrared absorption of LT MBE GaAs layers. Furthermore it is found that ESR-spectra of LT GaAs epitaxial layers are very similar to those observed in fast neutron irradiated bulk GaAs crystals.