Optical and Electrical Properties of Ag-Doped In2S3 Thin Films Prepared by Thermal Evaporation

Ag-doped In2S3 (In2S3:Ag) thin films have been deposited onto glass substrates by a thermal evaporation method. Ag concentration is varied from 0 at.% to 4.78 at.%. The structural, optical, and electrical properties are characterized using X-ray diffraction (XRD), spectrophotometer, and Hall measurement system, respectively. The XRD analysis confirms the existence of In2S3 and AgIn5S8 phases. With the increase of the Ag concentration, the band gap of the films is decreased gradually from 2.82 eV to 2.69 eV and the resistivity drastically is decreased from ~103 to 5.478×10-2 Ω·cm