The use of micro-raman spectroscopy to monitro high-pressure high-temperature ananealing lf ion-implanted GaN films

摘要

We have investigated the high-rpessure high-temperature annealing of Mg/P-implanted GaN films using visible and ultraviolet (UV) micro-Rman spectroscopy. The results illustrate the use of Raman spectroscopy to monitopr processing of GaN where fast feedback is required. The structural quality and he stress in ion-implanted GaN films was monitored in a 40nm-thin surface layer of the sample as well as averaged over the sample layer thicness. We find the nearly full recovery of the crystalline quality of ion-implanted GaN films after annealing at 1400-1500 degC under introgen overpressures of 1.5 GPa. No significant dgreadation effects occurred in the GaN sufface layer during the annealing. The high nitrogen overpressures proved very effective in preventing the nitrogen out-diffusion from the GaN surface. Stress introduced during the annealing was monitored. Raman spectra of ion-implanted GAN films were investigated at different temperatures and excitation wavelengths to study the GaN phonon density of states.