18% Thin-Absorber CdSeTe/CdTe Solar Cells

High-efficiency thin CdSeTe/CdTe solar cells with absorber thicknesses of 1 µm, composed of 500 nm CdSeTe and 500 nm CdTe, and 1.5 µm, with 500 nm CdSeTe and 1000 nm CdTe, were fabricated using close-space sublimation. Optimization of post-deposition treatments, including CdCl<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>, Cu doping, and Te at the back was crucial for achieving high performance. Typical optical and electrical characterization techniques were done to analyze device performance and identify loss mechanisms. The resulting devices had efficiencies as high as 16% for 1-µm absorbers and 18% for 1.5-µm absorbers. The results demonstrate the potential of thin-absorber CdSeTe/CdTe technology for achieving high efficiencies with reduced material consumption and processing times. Additional work is focused on continued data analysis, optimizing back contacts, and monitoring material uniformity to further improve performance.