Extremely high internal quantum efficiency of AlGaN-based quantum wells on face-to-face annealed sputter-deposited AlN templates

Abstract

Abstract This study investigated the influence of high-quality AlN templates on the internal quantum efficiency (IQE) of AlGaN-based multiple quantum wells (MQWs) using photoluminescence spectroscopy. An extremely high IQE of 90% at room temperature was obtained from MQWs on face-to-face annealed sputter-deposited AlN/sapphire templates. The dependence of efficiency curves on temperature indicated that nonradiative recombination centers were almost fully saturated under higher excitation power densities even at 400 K. Moreover, analysis of the efficiency curves using a rate equation model based on exciton recombination processes suggested that radiative recombination was the dominant recombination process even at 400 K.