Available online at www.sciencedirect.com ScienceDirect Materials Today: Proceedings 3 (2016) 4128–4133 www.materialstoday.com/proceedings 2214-7853© 2016 Elsevier Ltd. All rights reserved. Selection and Peer-review under responsibility of International conference on materials research and applications-2016. ICMRA 2016 Studies on Physical Properties of SnSe 2 Thin Films Grown by a Two-Stage Process K. Saritha, G. Phaneendra Reddy and K.T. Ramakrishna Reddy * Solar Photovoltaic Laboratory, Department of Physics, S.V. University, Tirupati-517502, Andhra Pradesh, India Abstract Tin diselenide (SnSe 2 ) thin films were prepared on glass substrates by using a two-stage process. It involves the sputtering of tin metallic precursors followed by selenization process using elemental selenium. The selenization was conducted in two-zone furnace at three different temperatures 300°C, 350°C and 400°C. The physical properties of as-deposited thin films were evaluated using appropriate techniques. The X-ray diffraction patterns indicated that the films formed at 350°C had only SnSe 2 phase with (001) plane as its preferred orientation, which exhibits hexagonal crystal structure while the thin films formed at other temperatures showed secondary phases also. The scanning electron micrographs revealed uniform and plate like morphology for as-grown layers. The energy dispersive X-ray analysis of the films formed at 350°C confirmed that the compositional ratio of Sn and Se was in stoichoimetry while the other layers showed a deviation. The optical absorbance data obtained from UV-Vis spectrophotometer was used to find out the optical band gap of SnSe 2 thin films and was found to be in the range of 1.60 - 1.81 eV. These results are presented and discussed in detail. © 2016 Elsevier Ltd. All rights reserved. Selection and Peer-review under responsibility of International conference on materials research and applications-2016. Keywords: SnSe2; Two stage process; Sputtering; Selenization 1. Introduction Tin selenides are the least thermally conductive crystalline materials. Particularly tin diselenide (SnSe 2 ) belongs to the binary compound of metal chalcogenide family with a melting point of 675°C [1]. In tin diselenide, selenium acts as anion and tin (+4) acts as electropositive element. It is an n-type semiconductor having nearly 1 to 2 eV as its energy band gap. Its fundamental edge absorption is due to forbidden, indirect and direct transitions. SnSe 2 structure is composed of planes of hexagonally close packed chalcogen Se atoms interleaved with planes of metal Sn atoms to give the stacking sequence of Se-Sn-Se in the c-direction of the unit cell. Thus it adopts the CdI 2 layered structure with hexagonal unit cell. * Corresponding author. Tel.: +91 9441137898; E-mail address:ktrkreddy@gmail.com