Abstract
In order to improve the quality of AlGaN-based crystals for deep-UV light emission, we studied photoluminescence (PL) of four MOCVD-grown AlGaN quantum wells from standpoints of growth temperature and In incorporation. A growth at 880℃ with In flow was shown to be best among them based on the comparative measurements on PL spectra, temperature and excitation density dependence. With increasing excitation density, a saturation of nonradiative recombination centers takes place and increases internal quantum efficiency. A simplified rate-equation analysis yielded weak carrier density dependence of nonradiative recombination constant for each sample. Detailed optimization of growth condition with a minute In incorporation is promising for improving the internal quantum efficiency.
