Abstract

In this research, Sn-doped In₂S₃ thin films were prepared on glass substrates by spray pyrolysis technique. The effect of tin impurity on the structural, morphological, electrical, thermo-electrical, optical and photoconductive properties of films has been investigated. The tin to indium atomic ratios (x = [Sn]/[In]) were varied from 0 to 0.15 in the spray solution. X-ray diffraction analysis showed the formation of cubic β-In₂S₃ phase in all deposited films. Scanning electron microscopy images indicated that nanostructure of the condensed films has a particle-cluster to rock-plate growth type. The Hall effect measurements have shown n-type conductivity in all deposited films. The lowest resistance of 1.3 MΩ/□ and the highest the carrier concentration of 3.93 × 10¹⁸ cm^− 3were obtained for the film deposited with x = 0.08. The maximum of the Seebeck coefficient equal to 132 μVK^− 1 was obtained at 400 K for the film deposited with x = 0.15. The average transmittance of films varied over the range of 40–60%. The band gap values of samples were obtained in the range of 2.89–3.75 eV for direct and 2.61–3.37 eV for indirect allowed transitions. From the photoconductivity studies, the sample prepared with x = 0.05 exhibited the highest photoconductivity among the In₂S₃:Sn films.