GaN-MOVPE growth and its microscopic chemistry of gaseous phase by computational thermodynamic analysis

We studied microscopic chemistry of gaseous phase in GaN growth by computational thermodynamic analysis of metalorganic vapor phase epitaxy with two- and three-flow methods. Correlations between quality of GaN layers and gaseous phase chemistry were found from the computational analysis. It was confirmed that laminar flow on a substrate during growth was necessary to obtain a high-quality GaN layer in spite of high growth temperature. Optimum decomposed-species V/III ratio (NH₂/GaCH₃) were considered in the range of 1000-2000 to achieve high electron mobility more than 200 cm²/Vs. Two-flow method was easier to achieve the optimum condition than three-flow method both in experiments and in computational analysis.