Patterned and unpatterned quantum-well structures were implanted with 100keV Ar ions in order to investigate the lateral and vertical extents of the implantation-induced defect profile. The degradation of the photoluminescence emission intensity of implanted quantum-well layers, at well-defined positions below the sample surface, was used to characterize the damage. The depth profile of the exponential tail of the damage distribution could be determined, as a function of crystal orientation, with a defect sensitivity of between 1014 and 1018/cm3. The lateral spread of the damage profile was evaluated by measuring the quantum efficiency as a function of the implantation mask width. When compared with randomly implanted samples, implantation along a crystallographic axis led to a clear increase in the longitudinal damage range and a reduced lateral spread.

A.Kieslich, H.Doleschel. J.P.Reithmaier, A.Forchel, N.G.Stoffel: Nuclear Instruments and Methods in Physics Research B, 1995, 99, 594-7