The influence of underlying layer on morphology of InGaN quantum dots self-assembled by metal organic vapor phase epitaxy

Abstract

The influences of two different underlying layers of GaN on the growth of InGaN quantum dots self-assembled by metal organic vapor phase epitaxy are studied. One is a 2 μm high-temperature grown GaN/sapphire template, and the other includes a 15 nm GaN layer on the template which possesses the same growth temperature with InGaN. The results show the latter can reduce the dot diameter greatly, and hence increase the aspect ratio of quantum dots to about 0.5. This morphology improvement is considered related to the strain area reduction at certain locations when InGaN is deposited on low-temperature grown GaN. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.