Growth of quaternary AlInGaN with various TMI molar rates

We report the growth of very thick (∼400 nm) quaternary AlInGaN layer on GaN/sapphire template by metalorganic chemical vapor deposition. By properly controlling the trimethylindium molar flow rate, we successfully achieved an Al0.89In0.02GaN layer perfectly lattice matched to the underneath GaN buffer. It was found that we can minimize the number of V-defect pits and the linewidth of X-ray (3 0 2) diffraction peak. Other than the AlInGaN-related photoluminescence peak, we also observed a low-energy band which is originated from indium segregation.