Tunneling-Enhanced Recombination in Polycrystalline CdS/CdTe Solar Cells

Abstract

The dominant dark current transport mechanism in as-grown and CdCl2 processed CdS/CdTe heterojunction solar cells for temperatures below 300 K was investigated. The current-voltage properties of these solar cells is explained via tunnelling enhanced bulk and interface recombination models which give a quantitative description of the electronic loss mechanisms in the chalcopyrite-based heterojunction solar cells. The temperature dependence of the saturation current and the diode ideality factors of the as-grown and CdCl2 processed CdTe solar cells are shown to be well described by this model.