Microscopic Opto-Electronic Characterization of CuInSe2 Solar Cells. Final Report, 1 April 1985-31 March 1986

摘要

The objective of this work was to investigate how the polycrystalline material currently used in CuInSe sub 2 solar cells differs from single-crystal material. A light probe was introduced, equivalent to approximately 1000 suns, and cells were scaled downwards. Considerable variation was seen in the light current response. The current-voltage curves revealed the variations to be roughly superimposed, the same behavior as that resulting from variations in light intensity. Large J/sub sc/ values, average reflected light scattered 25 sup 0 , and significant point-to-point differences in reflected light all suggested an optical explanation for the spatial variations in cell response. Photoluminescence showed some spatial variation and revealed a high level of donor-acceptor compensation. The compensation is less during a typical anneal cycle for evaporated CuInSe sub 2 , but still seems higher than that for single crystals. The defect levels deduced from the polycrystalline CuInSe sub 2 appear consistent with those for n- and p-type crystalline material. (ERA citation 11:053771)