Characterization of low energy ion-induced damage using the multiple quantum well probe technique with an intervening superlattice

Abstract

Observations of low energy ion-induced damage of III–V semiconductor materials indicate that the ion damage penetrates much more deeply than simple projected ion range theory would suggest. Our present experiments are aimed to investigate two proposed mechanisms of this low energy, long range ion-induced damage: namely, (1) ion channeling and (2) defect generation and diffusion. Accordingly, we have designed a set of well-controlled ion exposure experiments based on the multiple quantum well (MQW) probe technique. Our experimental approach incorporates both the use of structural variations of our MQW probe structures and Ar ion beam parameter variations. An intervening superlattice placed in the surface barrier region of one of our MQW probe structures is effective in reducing observed defects. Bombardment carried out at a variety of substrate temperatures (78 K, room temperature, and 150 °C) reveal decreased damage profiles at the lowest temperature.