Performance comparison of hybrid sputtering/evaporation CuIn1−Ga Se2 solar cells with different transparent conducting oxide window layers

Abstract In this work we report the results of a study where solar cells were prepared with CuIn 1− x Ga x Se 2 (CIGS) as the absorber layer deposited by a two-stage hybrid sputtering/evaporation method and finished with two different transparent conducting oxides (TCO): i-ZnO/ZnO:Al or indium tin oxide (ITO). The solar cell structure is soda lime glass/Mo/CIGS/CdS/TCO. The ZnO and the ITO window layers were deposited by RF-magnetron and DC-magnetron sputtering at room temperature respectively. The deposition of these two TCOs was optimized to obtain similar parameters. In both cases the control samples showed sheet resistivities at around 50 Ω/□ and transmission coefficients around 85% in the visible spectral range for layers 300 nm thick. The I – V characteristics of finished solar cells under simulated solar spectrum illumination have been measured and the cell parameters analyzed.