Molar ratio S/In effect on properties of sprayed In₂S₃ films

¹ Laboratoire de Physique des Matériaux et des Nanomatériaux Appliquée à l’Environnement, Université de Gabès, Faculté des Sciences de Gabès, Cité Erriadh Manara Zrig, 6072 Gabès, Tunisia
² LPMS, Département de Génie Industriel, Ecole Nationale d’Ingénieurs de Tunis, PB 37, Le Belvédère 1002, Tunis, Tunisia
³ Department of Physics, College of Applied Science, Umm Al-Qura University, Makka El Mukarrama, Saudi Arabia
⁴ GPS, Tour 23, 2 Place Jussieu, 75251 Paris Cedex 05, France
⁵ LPMC, Faculté des Sciences de Tunis, Le Belvédère 1060, Tunis, Tunisia

^a e-mail: timoumiabdelmajid@yahoo.fr

Received: 30 May 2013
Accepted: 9 July 2013
Published online: 7 August 2013

Abstract

We have studied the structural, morphological and optical properties of In₂S₃ layers deposited on glass substrate by the spray pyrolysis method with the molar ratio S/In varies from 1 to 4. The substrate temperature was maintained at 613 K. The characteristics of these films have been determined by X-ray diffraction (XRD), optical absorption-transmission and atomic force microscopy (AFM). Their structure is strongly dependent on the molar ratio. The deposit is mainly constituted by the β phase towards (4 0 0) direction. No characteristic peaks were observed for other impurities such as In₂O₃, S or In₂(OH)₃. The best crystallinity and surface morphology are obtained at molar ratio equal to 2.5. At this ratio, the crystallites coalesce and the local roughness is of the order of 1 nm. Optical transmission of 80% has been achieved in the visible spectrum. In₂S₃ band gap energy reached 2.63 eV from layers with x = 2 and deposited at T_s = 613 K.