Difficulties encountered in developing numerical InP solar cell models

A number of different InP solar cell models have appeared in the literature, with the ultimate goals of identifying loss mechanisms and designing an optimal cell. Approaches have ranged from traditional analytical models to commercially-available finite element device simulation packages. However, values other than those obtained experimentally for material parameters are often employed in order to fit experimental cell parameters. Effects such as bandgap narrowing, surface recombination, photon recycling and two-dimensional current flow can significantly alter performance predictions, and care must be taken to ensure that they are properly accounted for. This paper describes modeling efforts of InP solar cells using ADEPT, a multidimensional complete numerical simulation package developed at Purdue University