Optical investigation of implantation damage in GaAs/AlGaAs quantum wells

Abstract

We used optical spectroscopy to study the depth range distribution of Ar + implantation induced damage at ion energies between 15 and 170 keV. The photoluminescence efficiency of implanted GaAs/GaAlAs quantum wells is determined as a function of the ion energy and the angle of incidence. The evidence for damage by channeled ions is investigated by varying the incidence angle of the Ar ion beam through the major crystallographic axes of the sample. Implantations along the axial channels of the zinc-blende crystal lead to a dramatic decay of the photoluminescence intensity from quantum wells much deeper than in the case of random incidence. In particular channeling simulations with a new molecular dynamics program reproduce the experimentally observed energy and angular dependence of the damage due to channeled ions.