Growth Mechanism of Polar-Plane-Free Faceted InGaN Quantum Wells

Abstract

The growth mechanisms of three-dimensionally (3D) faceted InGaN quantum wells (QWs) on (1122) GaN substrates are discussed. The structure is composed of (1122), {1101}, and {1100} planes, and the cross sectional shape is similar to that of 3D QWs on (0001). However, the 3D QWs on (1122) and (0001) show quite different inter-facet variation of In compositions. To clarify this observation, the local thicknesses of constituent InN and GaN on the 3D GaN are fitted with a formula derived from the diffusion equation. It is suggested that the difference in the In incorporation efficiency of each crystallographic plane strongly affects the surface In adatom migration.