Correlation between physical properties and growth mechanism of In₂S₃ thin films fabricated by electrodeposition technique with different deposition times

¹ Laboratoire de Photovoltaïques, Centre de Recherches et des Technologies de l’Energie Technopole Borjcedria,Bp 95 2050 Hammam lif, Tunisie
² Physics Department, Taif University, Saudi Arabia
³ Interfaces, Traitements, Organisation et Dynamique des Systèmes (ITODYS), Université Paris Diderot,Sorbonne Paris Cité, UMR CNRS 7086, 75205 Paris Cedex 13, France

^a e-mail: braik.zied@yahoo.fr

Received: 7 April 2015
Revised: 7 July 2015
Accepted: 12 August 2015
Published online: 30 September 2015

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.