SURFACE ORIENTATION DEPENDENCE OF GROWTH-RATE OF CUBIC GAN

The metalorganic vapor phase epitaxy (MOVPE) growth of cubic GaN has b een performed on the patterned GaAs(100) substrates which have (111)A or (111)B facets. It is found that the growth features are strongly de pendent on the configuration of the pattern. It is deduced that these features come from the surface-orientation-dependent growth rate, whic h is in the order (111)B > (100) > (111)A, combined with the diffusion of Ga adatoms on the surface. Taking advantage of the growth on the p atterned substrates, the diffusion length of the Ga adatoms on the GaA s(100) surface is estimated to be several microns in the typical case.