Correlation between physical properties and growth mechanism of In₂S₃thin films fabricated by electrodeposition technique with different deposition times

Abstract

Indium sulfide (In2S3) thin films were grown on ITO-coated glass substrate using the electrodeposition method. The effect of the deposition time on the structural, morphological, optical and electrical properties of the as-grown In2S3 thin films was studied. XRD spectra of the obtained films reveal the polycrystalline nature of (β-In2S3) with a tetragonal crystal structure along the (109) plane, and exhibit a sharp transition to the (0012) plane when the deposition time is extended beyond 20 min. Using atomic force microscope (AFM), the surface morphology shows a remarkable change in the grain size, thickness, and surface roughness when varying the deposition time. UV-VIS spectrophotometer show that the optical band gap values of In2S3 decrease from about 2.82 to 1.93 eV by extending the electrodeposition duration from 5 to 20 min. All films were found to have an n-type character with a lower electrical resistivity of about 1.8×10-3 Ω cm for films deposited at 20 min.