SYNTHESIS OF GAN NANOCRYSTALS BY SEQUENTIAL ION-IMPLANTATION

We have synthesized GaN nanocrystals by sequential implantation of Ga and N ions into a sapphire substrate followed by a postimplantation an neal. The nanocrystals have been identified as the wurtzite phase alph a-GaN structure by transmission electron microscopy, We also found tha t the nanocrystals are aligned with the sapphire following the relatio nship: (0001)(sapphire)\\(0001)(GaN) and (<11(20)over bar>)(sapphire)\ \(<11(20)over bar>)(GaN). The use of a sapphire substrate allows for t he measurements of optical properties, and near band-edge luminescence and the yellow band are observed in photoluminescence spectroscopy.