Illumination intensity dependence of the performance of interdigitated back contact heterojunction silicon solar cells and the effects of front surface field

Abstract

The performance of interdigitated back contact silicon heterojunction solar cells as a function of illumination intensity has been studied by two-dimensional simulation. A doped front surface field layer is effective to suppress the reduction of conversion efficiency at the illumination below 0.01 sun even with good front passivation and at 1 sun with poor passivation. The experimental devices showed the almost consistent results. For the illuminations above approximately 1 sun, the fill factor and efficiency decreased with illumination intensity, likely due to the increase in series resistance with the increase of “hole” current passing through the high potential barrier at the p-type heterojunction.