Growth and characterization of tin disulfide (SnS2) thin film deposited by successive ionic layer adsorption and reaction (SILAR) technique

Thin films of tin disulfide (SnS2) have been deposited by using low cost successive ionic layer adsorption and reaction (SILAR) technique. The deposition parameters such as SILAR cycles (60), immersion time (20s), rinsing time (10s) and deposition temperature (27 degrees C were optimized to obtain good quality of films. Physical investigations were made to study the structural, optical and electrical properties. X-ray diffraction (XRD) patterns reveal that the deposited SnS2 thin films have hexagonal crystal structure. Energy dispersive X-ray analysis (EDAX) indicated elemental ratio close to those for tin disulfide (SnS(2.02)). Uniform deposition of the material over the entire glass substrate was revealed by scanning electron microscopy (SEM). Atomic force microscopy (AFM) showed the film is uniform and the substrate surface is well covered with small spherical grains merged in each other. A direct band gap of 2.22 eV was obtained. Photoluminescence (PL) showed two strong peaks corresponding to green and red emission. Ag/SnS2 junction showed Schottky diode like I-V characteristics. The barrier height calculated was 0.22 eV. Thermoelectric power (TEP) properties showed that tin disulfide exhibits n-type conductivity. (C) 2007 Elsevier B.V. All rights reserved.