Series resistance variation of polysilicon solar cells modified by electrochemical coating of heteropolytungstates

A model has been developed for the analysis of the series resistance in solar cells. The equation for the series resistance of the solar cells is evolved. The results obtained with this equation have been compared with the experimentally measured series resistance, in order to determine the effects of the electrodeposited heteropolytungstates on the series resistance in polysilicon solar cells. That leads to the study of the influence of the electrochemical coating of heteropolytungstates on the grain boundaries at the front surface of the polysilicon solar cells. The series resistance variation with the treatment time has been observed. This variation is due to the electrochemical reactions which occur on the front surface of the solar cells during treatment. We observed that the oxidation process increases the series resistance while the reduction of the heteropolytungstates and fixation of its reduced species on the front surfaces of the solar cells, decrease the series resistance and increase the cell's efficiency. (C) 1997 Elsevier Science Ltd.