An alternative method for the performance analysis of silicon solar cells

Abstract

An approximate formula for electron-hole generation rate has been proposed. The proposed approximation is found to give good representation of the actual generation rate provided by Dunbar and Hauser and by Fossum. In order to determine the applicability of this approximation attempts have been made to calculate short-circuit current, open-circuit voltage, and solar cell efficiency of an n+p silicon solar cell. The calculations involve consideration of nonuniform doping, spatial dependence of the band, and drift field for the n+ region, and band gap narrowing, Shockley–Read–Hall recombination, and Auger recombination for both n+ and p regions. The variations of short-circuit current, open-circuit voltage, and solar cell efficiency with doping concentration of the substrate p region are found to be in good agreement with results obtained from experiments. The trend of the results indicates that proper optimization of the width and impurity concentration of the diffused n region, of the width and impurity concentration of the substrate p region, and of the front-surface recombination velocity is necessary for achieving the highest efficiency of a solar cell.