These losses are due to surface and bulk recombination at metal or semiconductor contact and recombination in depletion region. These recombination losses mainly affect the open circuit voltage. Impurities, crystalline defects and incomplete chemical bond on semiconductor acts as traps for photoexcited carriers, and recombination on these traps cause the reduction of photocurrent. The reduction in the concentration of impurities and defects can increase the diffusion length of minority carriers and this can decrease the recombination losses in a solar cell [12].