RAMAN-SCATTERING IN ION-IMPLANTED GAN

Raman measurements were performed on molecular beam epitaxially grown GaN before and after implantation with Ar+, Mg+, P+, C+, and Ca+ ions. With increasing ion dose, new Raman peaks arise at 300, 360, 420, and 670 cm(-1), independent of the ion species. After rapid thermal annea ling at temperatures between 900 and 1150 degrees C for 15 s, the inte nsities of the Raman modes decrease with increasing temperature with t he exception of the 360 cm(-1) mode which shows a maximum in intensity after annealing at 900 degrees C. The mode at 300 cm(-1) is attribute d to disorder-activated Raman scattering, whereas the other three mode s are assigned to local vibrations of vacancy-related defects. (C) 199 8 American Institute of Physics.