Thin film CdTe solar cells with an absorber layer thickness in micro- and sub-micrometer scale

CdTe thin film solar cell with an absorber layer as thin as 0.5 mu m was fabricated. An efficiency of 7.9% was obtained for a 1-mu m-thick CdTe solar cell. An increased intensity of deep recombination states in the band gap, which was responsible for the reduced open-circuit voltage and fill factor for ultra-thin solar cells, was induced due to the not-well-developed polycrystalline CdTe microstructure and the CdS/CdTe heterojunction and the presence of Cu in the back contact. The experimental results presented in this study demonstrated that 1-mu m-thick absorber layer is thick enough to fabricate CdTe solar cell with a decent efficiency. (C) 2011 American Institute of Physics. [doi :10.1063/1.3644160]