Chemically Deposited Sb2 S 3 and Sb2 S 3 ‐ CuS Thin Films

Thin films of antimony sulfide have been deposited from chemical baths containing antimony trichloride and sodium thiosulfate maintained at 10°C. Upon annealing in nitrogen at 300°C for 1 h, the films become photosensitive with photo‐ to dark‐current ratio of two to three orders of magnitude at 2 kW m − 2 tungsten halogen radiation. The annealed films are crystalline with an X‐ray diffraction pattern matching that of stibnite, Sb 2 S 3 , (JCPDS 6‐0474) and show an optical bandgap of 1.78 eV. Deposition of a thin film of CuS on the antimony sulfide thin film and subsequent annealing in nitrogen at 250°C for 1 h produces films with acceptable solar control characteristics: integrated visible transmittance, T vis , 15%; integrated visible reflectance, R vis , 12%; integrated infrared transmittance, T ir , 14%; integrated infrared reflectance, R ir , 36%; and a shading coefficient of about 0.35. The X‐ray diffraction patterns of the annealed Sb 2 S 3 ‐ CuS thin films indicate the formation of a ternary compound with the structure of famatinite, Cu 3 SbS 4 .