Nitride growth at 1μm/h was carried out by means of migration-enhanced molecular beam epitaxy, using radio-frequency plasma N. The threading dislocation density of the resultant GaN was estimated to be between 1.0 x 1010 and 3.0 x 1010/cm2; as based upon cross-sectional transmission electron microscopic images. A marked improvement in electrical properties was obtained by growing an intermediate AlN/GaN multiple layer at 750C. Cross-sectional transmission electron microscopic images showed that threading dislocations were bent or terminated at the multiple intermediate layer.

High-Quality GaN on AlN Multiple Intermediate Layer with Migration Enhanced Epitaxy by RF-Molecular Beam Epitaxy D.Sugihara, A.Kikuchi, K.Kusakabe, S.Nakamura, Y.Toyoura, T.Yamada, K.Kishino: Japanese Journal of Applied Physics - 2, 2000, 39[3A/B], L197-9