The effects of growth temperature and V/III ratio upon the initial nucleation of islands on the GaN (00•1) surface were investigated. It was found that the InN nuclei density increased upon decreasing the growth temperature from 375 to 525C. At lower temperatures, the InN films took the form of small, closely-packed islands, with diameters less than 100nm. At high temperatures, the InN islands were larger and well-separated; approaching an equilibrium hexagonal shape due to enhanced adatoms surface diffusion. At a growth temperature of 500C, controllable densities and sizes of separate InN islands could be achieved by adjusting the V/III ratio. The larger islands led to fewer defects when they coalesced.

The Influence of Growth Temperature and Input V/III Ratio on the Initial Nucleation and Material Properties of InN on GaN by MOCVD. H.Wang, D.S.Jiang, J.J.Zhu, D.G.Zhao, Z.S.Liu, Y.T.Wang, S.M.Zhang, H.Yang: Semiconductor Science and Technology, 2009, 24[5], 055001