Grain boundary recombination analysis of GaAs Schottky barrier solar cells

A cylindrical grain is used to model the short circuit current density of a thin film polycrystalline GaAs Schottky barrier solar cell. Both backwall and frontwall solar cells are considered and it is found that the optimum thickness for either cell is less than 2.5 μm if reflection of solar energy from the back metallic contact is considered. The grain size and grain boundary recombination velocity affects each cell in the same way. However, the ohmic contact recombination velcocity has a greater influence on the backwall solar cell. The conclusion of this study is that although the backwall cell is potentially more efficient, the frontwall cell is less influenced by semiconductor and contact parameter variation and thus, for production quantities, the frontwall cell will yield more consistent results.