Heteroepitaxy and Characterization of Low-Dislocation-Density GaN on Periodically Grooved Substrates

We have developed a new method to prepare low-dislocation-density GaN by using periodically grooved substrates in a conventional MOVPE growth technique. This new approach was demonstrated for GaN grown on periodically grooved α-Al 2 O 3 (0001), 6H-SiC(0001)Si and Si(111) substrates. Dislocation densities were 2×10 7 cm −2 in low-dislocation-density area.