Structural, optical and electrical properties of β-In2S3-3xO3x thin films obtained by PVD

b-In2S3-3xO3X thin films have been synthesized following a dry physical process on glass substrates. The highest temperature used during the elaboration of the films is 473 K. The films have been structurally and optically characterized by X-ray diffraction, electronic microprobe analysis, X-ray photoelectron spectroscopy, scanning electronic microscopy and atomic force microscopy. They crystallize in the tetragonal beta-In2S3 structure. Their optical band gap varies from 2.1 eV, when they are pure beta-In2S3, to 2.9 eV when they contain 8.5 at.% of oxygen. The electrical properties of the thin films have also been determined, they have n-type electrical conductivity of approximately 10(-3) S(.)cm(-1). All these properties make beta-In2S3-3xO3x thin films good candidates to substitute CBD-CdS as buffer layer in CIGS-based solar cells. (C) 2002 Elsevier Science B.V. All rights reserved.