Strain relaxation in thick ($1{\bar {1}}01$) InGaN grown on GaN/Si substrate

Abstract

AbstractWe demonstrated the growth of thick InGaN on ($1{\bar {1}}01$) GaN/Si. The InGaN layer showed a marked inclination along the 〈0001〉 projection direction. The InGaN with a higher indium composition showed a larger inclination. Owing to the lattice mismatch between InGaN and GaN, misfit dislocations and/or stacking faults are generated from the heterointerface, which resulted in a larger inclination. As the indium content increased, inclining was observed in the early stage of InGaN growth. After InGaN was substantially relaxed, the crystallinity was saturated or improved. The surface morphology also became roughened because of the strain relaxation to form triangular grains, and then recovered following the coalescence.