The influence of heat treatment on the crystallite size, dislocation density, stacking faults probability and optical band gap of nanostructured cadmium sulfide films

Nanocrystalline cadmium sulfide films were deposited on the ordinary glass slide substrates by chemical bath deposition. Two advanced X-ray diffraction analyses i.e. DIFFaX and eCMWP were applied and the microstructure of films was evaluated as a function of annealing temperature. The optical properties of samples were also studied, using the transmittance spectra in the wavelength range of 300-900 nm. Based on our studies, we have found that with the elevation of annealing temperature, the crystallite size increases, however, the dislocation density, the fraction of stacking faults and the band gap energy decrease and the outer cut-off radius of dislocation does not appreciably change. We can also see that the energy gap follows the linear, inverse square and quadratic relation with uniform strain, crystallite size and dislocation density, respectively. Comparing the microstructure evaluated from eCMWP with the results of Scherrer formula and Williamson-Hall plot shows that there is no agreement between the results of advanced and early X-ray diffraction analysis. (C) 2014 Elsevier Ltd. All rights reserved.