Thin film solar cells of chemically deposited SnS of cubic and orthorhombic structures

Chemical bath deposition yields SnS thin films of cubic, SnS-CUB, or of orthorhombic, SnS-ORT, crystal structures. They have optical bandgaps (Eg) of 1.7 eV and 1.1 eV, respectively. We present solar cells produced by depositing these SnS thin films on glass substrates coated with F-doped SnO2 (SnO2:F) as transparent conducting oxide (TCO) and CdS film of Eg, 2.6 eV as window layers. Chemical bath for depositing SnS-CUB thin films contained thioacetamide, while that for SnS-ORT contained thiosulfate as the source of sulfide. With SnS-CUB, TCO/CdS(80 nm)/SnS-CUB(400 nm)/C-Ag solar cells showed open circuit voltage (Voc) of 0.368 V, short circuit current density (Jsc) of 2.7 mA/cm2, fill factor (FF) of 33% and conversion efficiency (η) of 0.33%. Solar cells with CdS (120 nm) SnS-ORT (1200 nm) thin films showed Voc, 0.336 V; Jsc, 13 mA/cm2; FF, 25% and η, 0.96%. For a solar cell with both SnS-CUB and SnS-ORT absorber films: TCO/CdS(80 nm)/SnS-CUB(200 nm)/SnS-ORT(300 nm)/C-Ag, Voc was 0.488 V; Jsc, 6.96 mA/cm2, FF, 41% and η, 1.38%.