Table of Contents
ISRN Condensed Matter Physics
Volume 2013 (2013), Article ID 142029, 6 pages
http://dx.doi.org/10.1155/2013/142029
Research Article

Thickness-Dependent Physical Properties of Coevaporated Cu4SnS4 Films

Department of Physics, Sri Venkateswara University, Tirupati 517 502, India

Received 17 May 2013; Accepted 17 June 2013

Academic Editors: S. Krukowski, Y. Ohta, T. Prokscha, and S. Wang

Copyright © 2013 V. P. Geetha Vani et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Cu4SnS4 films of different thicknesses were prepared by thermal coevaporation technique on glass substrates at a constant substrate temperature of 400°C. The layer thickness was varied in the range 0.25–1 μm. The composition analysis revealed that all the evaporated films were nearly stoichiometric. The XRD patterns indicated the presence of a strong (311) peak as the preferred orientation, following the orthorhombic crystal structure corresponding to Cu4SnS4 films. Raman analysis showed a sharp peak at 317 cm−1, also related to Cu4SnS4 phase. The optical transmittance spectra suggested that the energy band gap decreased from 1.47 eV to 1.21 eV with increase of film thickness. The hot-probe test revealed that the layers had p-type electrical conductivity. A decrease of electrical resistivity was observed with the rise of film thickness.