Parameter studies and analysis of high efficiency Cu(In,Ga)Se/sub 2/ based solar cells

Solar cells based on Cu(In,Ga)Se/sub 2/ with gallium contents of 20% and 40% have been prepared and analyzed. Efficiencies exceeding 12% have been obtained. This contribution focuses on XRD, XPS and UPS analysis of these films. The influence of morphology, orientation of the grains, bulk composition, and secondary phases detected by surface analysis on the solar cell characteristics are presented and discussed. The existence of a metallic behavior on the Cu-rich side is shown and correlated to a shift in the Auger structure of Se and Cu. The possibility of passivating oxides is demonstrated.<
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