Measurement of the non-radiative minority recombination lifetime and the effective radiative recombination coefficient in GaAs

The combination of time-resolved (TR) and power-dependent relative (PDR) photoluminescence (PL) measurements reveals the possibility of separating the radiative and non-radiative minority carrier lifetimes and measuring the sample-dependent effective radiative recombination coefficient in direct bandgap semiconductors. To demonstrate the method, measurements on 2 mu m thick p-type GaAs double-hetero structures were conducted for various doping concentrations in the range of 5x10(16) and 1x10(18) cm(-3). With a photon recycling factor of 0.76 +/- 0.04 the radiative recombination coefficient was determined to be (3.3 +/- 0.6) x 10(-10) cm(3)s(-1) for the structures with a doping concentration below 1*10(18) cm(-3), whereas the effective radiative recombination parameter for an absorber thickness of 2 mu m was directly measured to be (0.78 +/- 0.07) x 10(-10) cm(3)s(-1). For a doping concentration of 1 x 10(18) cm(-3), the radiative recombination coefficient decreases significantly probably due to the degeneracy of the semiconductor. (C) 2019 Author(s).