Influence of strain and buffer layer type on In incorporation during GaInN MOVPE

We have studied the growth behaviour of GaN by metalorganic vapor phase epitaxy on various buffer layers. GaInN grown on high quality GaN buffers is coherently strained up to a thickness of ∼100 nm. When grown on AlGaN, the strain remains unchanged up to a critical Al content, above which relaxation was observed. In parallel, the In content increased significantly. When grown on lower quality GaN, the strain in our GaInN layers also relaxed and the In content increased. Therefore, we suggested a relation between In incorporation efficiency and defect structure on the growing epilayer surface.