Quenching by Copper Atoms of the EL2-induced Luminescence in GaAs

It is shown that the introduction of copper atoms into GaAs crystals containing antistructure defects EL2 (isolated arsenic atoms on gallium sites As_Ga) leads to a practically complete disappearance of the EL2-induced luminescence bands peaked at 0.63 and 0.68eV. This effect is connected with the passivation of the EL2 defects (i.e. with the substantial decrease in their concentration) because of their interaction with copper atoms (they become bound by copper atoms) resulting in an appearance of electrically inactive AS_GaCU_Ga complexes.