In-Redistribution in a GaInN Quantum Well upon Thermal Annealing

Abstract

A GaInN quantum-well structure with an average In-concentration of 16%, grown by metal organic chemical vapor deposition (MOCVD) on a SiC substrate, was studied by transmission electron microscopy (TEM) and photoluminescence spectroscopy (PL) before and after an one-hour annealing treatment at 980 C. Due to the heat treatment, the formation of In-rich clusters with extensions between 10 nm and 100 nm and In-concentrations above 80% was observed. Nevertheless, the PL exhibits a blue shift in the PL-peak energy of about 90 meV compared to the asgrown sample and do not show a significant influence of the In-rich clusters on the emission wavelength.