Selective-area metalorganic vapour phase epitaxy of GaN was investigated using optimized growth conditions for layer (Frank–van der Merwe) growth, and GaN-template substrates having a low dislocation density. The surface of a GaN hexagon, 16µm in diameter, had a single wide terrace over almost the entire area (step-free surface), when there were no screw-type dislocations in the finite area. Step-free GaN hexagons grew in the two-dimensional nucleus growth mode and had an approximately eight times lower growth rate than that of a GaN film grown in the step-flow mode under the growth conditions used here.

Step-Free GaN Hexagons Grown by Selective-Area Metalorganic Vapor Phase Epitaxy. T.Akasaka, Y.Kobayashi, M.Kasu: Applied Physics Express, 2009, 2[9], 091002