REDUCED LATERAL STRAGGLING OF IMPLANTATION-INDUCED DEFECTS IN III V HETEROSTRUCTURES BY ION-IMPLANTATION ALONG CHANNELING DIRECTIONS/

Argon ions at an energy of 50 keV were implanted in patterned GaInAs/G aAs quantum well structures to investigate the lateral broadening of t he implantation induced defect profile. Tn order to study the influenc e of ion channeling on the lateral spread of the damage distribution, implantations were carried out along channeling axes and along random directions. The degradation of the photoluminescence emission intensit y of the laterally damaged quantum well layers was measured as a funct ion of the implantation mask width. The experimental results were mode led by using a simple diffusion calculation, which considers the diffu sivity of the electron-hole pairs beneath the implantation mask. This model allows the evaluation of an effective lateral straggling length for channeling as well as for random implantations. In comparison to r andomly implanted samples, a clearly reduced lateral spread of the dam age profile could be determined for implantations along the [100]- or the [110]-axis of the crystal. (C) 1996 American Institute of Physics.