We report the growth of high quality molecular beam epitaxy (MBE) AlGaAs, AlGaAs/GaAs/AlGaAs, and AlAs/GaAs/AlAs multiple quantum wells (MQWs) on (111)A GaAs substrates. For (111)A AlGaAs/GaAs/AlGaAs MQWs, there is no detectable photoluminescence (PL) at a growth temperature of 640 deg;C, and narrow PL linewidth can only be obtained at growth temperatures higher than 680 deg;C. A PL linewidth of 13.8 meV is measured at the growth temperature of 720 deg;C. To understand such growth temperature dependence of (111)A MQWs, we have investigated the material quality of (111)A AlGaAs at different growth temperatures. The strong PL integrated intensity of 640 deg;C grown (111)A AlGaAs indicates good material quality and a low concentration of nonhyphen;radiative recombination centers. However, the broad PL linewidth of 640 deg;C grown (111)A AlGaAs indicates the strong compositional modulation and a rough growth front. We have used AlAs instead of AlGaAs in order to reduce the compositional modulation and smooth the interface. A PL linewidth of 13.4 meV is measured for 640 deg;C grown (111)A AlAs/GaAs/AlAs MQWs, which is the narrowest value for (111)A MQWs. copy;1996 American Institute of Physics.
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