Grain boundary recombination and efficiency of polycrystalline silicon solar cells

The dependence of grain boundary (GB) space-charge potential barrier height (qV g ), effective diffusion length of minority carriers L* n , and the efficiency of polycrystalline silicon (PX-Si) solar cells on grain size is studied theoretically. The computations are done by considering Gaussian energy distribution for GB interface states. It is observed that a good agreement between the theoretical results and the available experimental data for efficiency of PX-Si solar cells can be achieved only when the variation of diode quality factor with grain size is considered.