Abstract
CuSbS2 is an emerging potential compound semiconductor for absorber layer in thin film heterojunction solar cell. Spray pyrolysis technique has been successfully employed to deposit CuSbS2 thin films onto soda-lime glass substrates held at different substrate temperatures in the range of 220 °C–280 °C. The structural and optical analysis revealed that films deposited at 260 °C are CuSbS2 with chalcostibite structure. The films deposited at other substrate temperatures contained binary/ternary phases like Cu2-xS, Cu3SbS4 and Cu12Sb4S13. The lattice parameters of CuSbS2 films are found to be a = 0.599 nm, b = 0.379 nm and c = 1.449 nm respectively. The band gap of CuSbS2 films is close to the optimum band gap (1.5eV) required for highest theoretical photovoltaic conversion efficiency. The optical absorption coefficient value lies in the range of 104 cm−1. The nature of these films is found to be p-type.
•CuSbS2 thin films are an alternative emerging potential solar cell absorber layer to traditional solar cell absorber layers like Cu(In,Ga)(S,Se)2, CdTe and Cu2ZnSn(S,Se)4.•CuSbS2 thin films were deposited by a low-cost technique.•Obtaining phase-pure CuSbS2 thin films is challenging task.•The optimum substrate temperature of CuSbS2 thin films was found.