GAN GROWTH BY METALLORGANIC VAPOR-PHASE EPITAXY - A COMPARISON OF MODELING AND EXPERIMENTAL MEASUREMENTS

A model for the growth of gallium nitride in a vertical metallorganic vapor phase epitaxy (MOVPE) reactor is presented and compared to exper imental growth rate measurements. For a mixture of nondilute gases, th e flow, temperature, and concentration profiles are predicted using re cent kinetic data. Growth rates are predicted based on simple reaction mechanisms and compared with those obtained experimentally These comp arative results show that the growth of GaN epi layers proceeds throug h an intermediate adduct of trimethylgallium and ammonia. Loss of addu ct species due to oligmerization leads to the lowering of the growth r ate. Quantification of this loss of reacting species is made based on experimentally observed growth rates. An apparent chemistry model is p resented based on the salient features of GaN MOVPE. Process condition s are perturbed to obtain trends in growth rate and uniformity in orde r to demonstrate the utility of such a model in optimizing the GaN MOV PE process.