International Journal of ChemTech Research CODEN (USA): IJCRGG ISSN: 0974-4290 Vol.7, No.2, pp 1038-1044, 2014-2015 ICONN 2015 [4 th - 6 th Feb 2015] International Conference on Nanoscience and Nanotechnology-2015 SRM University, Chennai, India Characterization of ZnIn 2 S 4 AND In rich-ZnIn 2 S 4 Films By Spray Pyrolysis Method S.Hemalatha 1 *, J.Tamil Illakkiya 1 , Rachel Oommen 1 , P.Usha Rajalakshmi 1 , 1 Department of Physics, Avinashilingam Institute for Home Science and Higher Education for Women, Coimbatore-641 043, India. Abstract : Using the Spray pyrolysis method, Zinc thioindate (ZnIn 2 S 4 ) and In rich-Zinc thioindate thin films were deposited on a glass substrate with the molar ratio of Zn/In = 4.6, 3.1 respectively using ZnCl 2 , InCl 3 and SC(NH 2 ) 2 as precursor material with substrate temperature of 350˚C. From XRD analysis, the position of the peak was shifted with increasing the Zn/ In molar ratio which is well agreed with the Raman spectrum. Optical study shows the maximum transparency of nearly 80% in NIR region. Absorbance shows the maximum for ZIS thin film compared to In rich film. The absorbance edge of ZIS and In rich ZIS film were observed to be around 462 nm and 750 nm respectively. The E g value of stoichiometric and In rich ZIS film were calculated as 2.1eV and 2.3eV. Morphology has great impact on the molar ratio revealing flower like morphology was observed for ZIS film. Composition of the film was observed using the EDAX spectrum. The presence of Indium rich in ZIS film was confirmed by EDAX analysis. Keywords: ZnIn 2 S 4, In rich ZnIn 2 S 4 thin films, spray pyrolysis, XRD, UV-Vis-NIR, Raman, FE-SEM with EDAX. Introduction Wide band gap semiconductor materials have been the center of various studies in the last decade, owing to their physical properties and numerous applications including solar cell.Polymorphism of inorganic materials has attracted extensive interest in many applications. Different types of polymorphs usually exhibit different properties. Zinc indium sulphide is a ternary chalcogenide which belongs to AB 2 X 4 (A=Zn, Cd, Hg, B=Al, Ga, In, X=S, Se, Te) exhibited different polymorphs 1 .Several layered ternary intermediate phases are formed in the ZnS-In, S, system with the general formula Zn m In 2 S 3+m (m = 1,2,3, ...) and that a fairly large variety of polytypic forms exists for each of these phases 2 . ZnIn 2 S 4 is a ternary chalcogenide with two distinct polymorphs: hexagonal and cubic. According to recent studies physical and electronic properties of these compounds could play a crucial part in the establishment of new devices ZnIn 2 S 4 has been part of many recent experimental works 3,4 . due to its possible uses in areas such as photo-catalysis 5,6 , thermoelectricity 7 , photoconduction 8 , Charge storage 9 . The indirect band gap (1.8– 2.1 eV) of ZnIn 2 S 4 is comparable to the solar spectrum and is thus suitable for energy conversion applications 10 , ZnIn 2 S 4 thin film prepared by various deposition condition such as hydrothermal method 11 , electro deposition 12 , atomic layer deposition 13 ,spin coating method 14 ,microwave-assisted synthesis equipment 15 , MOCVD 16 , magnetron sputtering 17 , CBD method 18 , facile solvothermal 19 , spray pyrolysis 20,21 , Successive ionic layer adsorption and reaction (SILAR) 22 , solvothermal