Open-Circuit Voltage, Fill Factor, and Efficiency of a CdS/CdTe Solar Cell

The dependences of the open-circuit voltage, fill factor, and efficiency of the thin-film CdS/CdTe solar cell on the resistivity rho and carrier lifetime tau in the absorbing CdTe layer were studied. In the common case in which the uncompensated acceptor concentration and the electron lifetime in the CdTe layer are within 10(15)-10(16) cm(-3) and 10(-10)-10(-9) s, the calculation results correspond to the achieved efficiency of the best thin-film CdS/CdTe solar cells. It was shown that, by decreasing rho and increasing tau in the absorbing CdTe layer, the open-circuit voltage, fill factor, and efficiency can be substantially increased, with their values approaching the theoretical limit for such devices.