Competitive adsorption effects in the metalorganic vapor phase epitaxy of GaN

Abstract
The growth mechanisms of GaN grown on a GaN buffer deposited onto sapphire substrates are studied here. The growth rate was measured at different temperatures versus ammonia flow and was found to decrease with increasing NH 3 flow. This surprising behavior is modeled in terms of competitive adsorption of species on the growing surface. Very good agreement is obtained between the model and the experimental data.