Temperature dependence of photoluminescence intensity from AlGaInP/GalInP-quantum well structures

The photoluminescence (PL) intensity of AlGaZnP/GaInP-quantum well structures under a continuous excitation condition was measured as a function of the crystal temperature (10-450 K). The thermal emission of carriers from the well layers to the barrier layers was investigated by generating the carriers only in the wells. The dependence of the PL intensity on the crystal temperature was analyzed by fitting a model function to the experimental results. The rapid decrease in PL intensity at temperatures higher than 200 K was found to be probably due to the emission of carriers into the barrier layers. The effective barrier heights obtained by the fitting are in good agreement with the band-energy alignment schemes of these crystals. When AlInP barrier layers were inserted directly beside the quantum wells, the emission of carriers to the quaternary layers through the AlInP layers was reduced, resulting in stronger PL intensity at higher temperatures and a larger effective barrier height. (C) 1997 American Institute of Physics.