OPTICAL INVESTIGATION OF IMPLANTATION DAMAGE IN GAAS ALGAAS QUANTUM-WELLS/

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 we lls is determined as a function of the ion energy and the angle of inc idence. The evidence for damage by channeled ions is investigated by v arying the incidence angle of the Ar ion beam through the major crysta llographic axes of the sample. Implantations along the axial channels of the zinc-blende crystal lead to a dramatic decay of the photolumine scence intensity from quantum wells much deeper than in the case of ra ndom incidence. In particular channeling simulations with a new molecu lar dynamics program reproduce the experimentally observed energy and angular dependence of the damage due to channeled ions.