Degradation of Photoluminescence from Quantum Wells Grown on Top of Low-Temperature Buffers

摘要

The high-resistivity properties of low-temperature (200-300 deg C) molecular-beam-epitaxy-grown GaAs and AlGaAs have great potential for device applications. The purpose of this study is to examine the effect of low-temperature buffers (LTB) on the crystal quality of epilayers grown on top. Photoluminescence (PL) from quantum wells grown at regular growth temperatures (620 deg C) is found to be sensitive to changes in crystal quality introduced by the LTB. Limiting LT AlGaAs buffer thicknesses to a critical thickness is found necessary for growing layers with good quantum-well PL.