Numerical modeling of the influence of photon recycling on lifetime measurements

Accurate determination of minority carrier lifetimes in solar cell devices is important for developing numerical models and making performance predictions. One popular technique is the time-resolved photoluminescence method. While the technique is straight-forward, analysis of the results can be complicated for direct band-gap semiconductors such as GaAs and InP due to the photon recycling effect. Reabsorption of radiative recombination radiation leads to an enhancement of the radiative lifetime, so that an estimate of the efficiency of the recycling process is required in order to permit extraction of the nonradiative component of the minority carrier lifetime. This paper investigates the effects of photon recycling on the measured minority carrier lifetime using ADEPT, a complete numerical simulation program developed at Purdue University. Initial modeling of TRPL measurements on a series of AlGaAs/GaAs/AlGaAs double heterostructures are presented