A drastic reduction in the dislocation density in a semi-polar (11•2) GaN stripe on a patterned Si substrate was achieved via the two-step selective growth of a GaN stripe. After depositing a SiO2 mask onto the (11•2) and (00•1) faces of a GaN stripe grown onto a (113) Si substrate, GaN was re-grown only on the (11•2) face. The dislocation density estimated from the dark-spot density in a cathodoluminescence image decreased greatly from 4.0 x 108 to 1.0 x 105/cm2 in the re-growth region. A transmission electron microscopy image also confirmed that there were no dislocations at the re-growth interfaces.

Drastic Reduction of Dislocation Density in Semipolar (1122) GaN Stripe Crystal on Si Substrate by Dual Selective Metal–Organic Vapor Phase Epitaxy. T.Murase, T.Tanikawa, Y.Honda, M.Yamaguchi, H.Amano, N.Sawaki: Japanese Journal of Applied Physics, 2011, 50, 01AD04