Spray pyrolysised tin disulphide thin film and characterisation

Thin film of tin disulphide on glass substrate is prepared by spray pyrolysis technique at a substrate temperature of 458 K. Using the hot probe technique the type of semiconductor is found to be n-type. X-ray diffraction analysis revealed the polycrystalline nature of the film with hexagonal structure and a preferential orientation along the (0 0 1) plane. Fibre-like surface morphology has been observed on the film. The surface composition of the elements is analysed with EDAX spectrum. A value of 3.85 x 10(-7)Omega(-1)cm(-1) for the room temperature (302 K) conductivity is determined using the four-probe method. Activation energy of about 0.25 eV is determined by plotting a graph between log (conductivity) versus reciprocal temperature. The optical absorption and transmittance spectra have been recorded for this film in the wavelength range 380-900 nm. Thickness of the film and variation of absorption coefficient with wavelength are determined using these spectral data. Band gap values of 2.16 eV with indirect allowed and 1.82 eV with indirect forbidden nature are observed for this pyrolysised SnS2 thin film. (C) 2002 Published by Elsevier Science B.V.