Structural, morphologic and optical characterization of In(2−x)AlxS3

Aluminum-doped indium sulfide thin films are deposited on glass by spray pyrolysis technique. The structure and the surface morphology of these films were characterized by X-ray diffraction and atomic force microscopy. The effects of aluminum ratio z and substrate temperature Ts, on the film structure and grain size are discussed. The influence of aluminum ratio on surface morphology is revealed by scanning electron microscope. Besides, energy dispersive spectrometry technique is used to compare atomic aluminum concentration in the film with aluminum ratio z in spray solution. Optical properties are studied by a spectrophotometer in the wavelength range 350–850 nm, at room temperature. Optical transmission and grain size are found to be maximal for z = 1.8 %. Moreover, band-gap energy is found to increase with aluminum ratio.