Optical study of implantation damage recovery from Si-implanted GaN

摘要

Comprehensive and systematic optical activation studies of Si-implanted GaN grown on sapphire substrates have been made as a function of ion dose and anneal temperature. Silicon ions were implanted at 200 keV with doses ranging from 1 X 10(13) to 5 X 10(15) cm(-2) at room temperature. The samples were proximity cap annealed from 1250 to 1350degreesC with a 500-Angstrom-thick AIN cap in a nitrogen environment. The results of photoluminescence measurements made at 3 K show a very sharp neutral-donor-bound exciton peak along with a sharp donor-acceptor pair peak after annealing at 1350degreesC for 20 s, indicating excellent implantation damage recovery. The results also indicate the AIN cap protected the implanted GaN layer very well during high temperature annealing without creating any significant anneal-induced damage. This observation is consistent with the electrical activation results for these samples. (C) 2004 Elsevier Ltd. All rights reserved.