AsGaantisites and their relation to EL2 defects in GaAs

Abstract

Photoquenching experiments of the magnetic circular dichroism and optically detected ESR and ENDOR signals of the As-antisite in various semi-insulating GaAs materials show that the isolated As_Ga defects cannot be identified with the EL2 defect in either charge state. Investigations of the spin-lattice relaxation time T₁ in conventional ESR and ODESR experiments show that the As_Ga defects seen in conventional ESR are not isolated As_Ga centres but most probably complexes of As_Ga defects. Therefore the correlations established previously between EL2 and As_Ga defects from conventional ESR experiments must be reinterpreted to be correlations between EL2 defects and complexes of As_Ga defects.