Growth orientation dependent photoluminescence of GaAsN alloys

Abstract

We report photoluminescence (PL) studies of both as-grown and electron-irradiated GaAsN epilayers on (311)A/B and (100) GaAs substrates. A long room-temperature (RT) PL lifetime, as well as an enhanced N incorporation, is observed in (311)B GaAsN epilayers as compared with (311)A and (100) samples. There is no direct correlation between the RT PL lifetime and the emission intensity from Ga vacancy complex detected at low temperature. The lifetime damage coefficient is relatively low for (311)B GaAsN. The irradiation-induced nonradiative recombination defects are suggested to be N- and/or As-related according to a geometrical analysis based on the tetrahedral coordination of GaAsN crystal. © 2012 American Institute of Physics.