Physical Mechanisms Contributing to Nonlinear Responsivity in Silicon Concentrator Solar Cells

Comparison of experimental data with the results of present models indicates that silicon solar cell operation at high solar concentration is not completely understood. That silicon concentrator cells are not fully understood was first recognized as nonlinearities experimentally observed in the response of the short circuit current to increasing solar concentration. In order to interpret the experimentally observed sublinear responsivities, a review in the literature of the physical mechanisms which have significance for solar cell operation at high solar intensities is essential. These phenomena include bandgap narrowing, Auger recombination, carrier diffusion, and the loss of base conductivity modulation. In this thesis, through modeling with the Solar Cell Analysis Program in One and Two Dimensions, SCAPlD and SCAP2D, an extensive study of these phenomena on the steady-state performance of two major cell designs for silicon concentrator solar cells, the conventional design and the back-contacted design, is made. The back-contacted design includes both the interdigitated back contact (IBC) solar cell and the point contact concentrator (PCC) solar cell.