Atomic-scale nanofacet structure in semipolar ð 20 2 1 Þ and ð 20 21 Þ InGaN single quantum wells

Atomic-scale nanofacets were observed in semipolar ð20 2 1Þ and ð20 21Þ InGaN quantum wells (QWs)/GaN quantum barriers interfaces. Transmission electron microscopy studies showed that these nanofacets were mainly composed of ð10 10Þ, ð10 1 1Þ; and ð10 11Þ planes, which led to significant fluctuations in QW thickness. Atom probe tomography studies were carried out to visualize the nanofacet structure. The In composition in the InxGa1%xN alloys followed a binominal distribution despite the formation of the nanofacet structure. One-dimensional (1D) Schrödinger– Poisson drift-diffusion simulation showed that these nanofacets and associated QW thickness fluctuations will lead to a large wavelength shift and a broadened spectral linewidth for semipolar QWs. © 2014 The Japan Society of Applied Physics