Sprayed zinc-cadmium sulfide films for Cu2S/ZnxCd1-xS heterojunction solar cells

Cu2S/ZnxCd1-xS solar cells with stable open-circuit voltages up to 0.784 V were formed on zinc-cadmium sulfide films deposited by spray pyrolysis. x was varied between zero and 0.7 by varying the spray solution composition. ZnxCd1-xS films formed Schottky diodes with evaporated chromium contacts; depletion layer width (in light) in the films increased with x, from 0.16 to 3.1 microns. Resistivity of the films increased exponentially with x. Optical band gap increased with x from 2.41 eV at x = 0 to 2.82 eV at x = 0.6.