A study of minority carrier lifetime versus doping concentration in n-type GaAs grown by metalorganic chemical vapor deposition

Abstract

Time-resolved photoluminescence decay measurements are used to explore minority carrier recombination in n-type GaAs grown by metalorganic chemical vapor deposition, and doped with selenium to produce electron concentrations from 1.3×1017 cm−3 to 3.8×1018 cm−3. For electron densities n0<1018 cm−3, the lifetime is found to be controlled by radiative recombination and photon recycling with no evidence of Shockley–Read–Hall recombination. For higher electron densities, samples show evidence of Shockley–Read–Hall recombination as reflected in the intensity dependence of the photoluminescence decay. Still, we find that radiative recombination and photon recycling are important for all electron concentrations studied, and no evidence for Auger recombination was observed.