Concentration dependence of carrier localization in InN epilayers

Abstract

The authors studied the concentration dependence of carrier localization in InN epilayers using time-resolved photoluminescence (PL). Based on the emission-energy dependence of the PL decays and the PL quenching in thermalization, the localization energy of carriers in InN is found to increase with carrier concentration. The dependence of carrier concentration on the localization energy of carriers in InN can be explained by a model based on the transition between free electrons in the conduction band and localized holes in the deeper tail states. They suggest that carrier localization originates from the potential fluctuations of randomly located impurities.