Characterization of zinc blende CuInS₂ nanostructured film: the XRD, Raman, FT-IR and UV-vis spectroscopical investigations

Zinc blende semiconductor CuInS₂ has not been focus of studies until recently. Ultrasonic spray pyrolysis (USP) method is used to deposit zinc blende CuInS₂ nanostructured film on glass substrate at 250°C in this study. The film was characterized by vibrational (FT-IR and Raman) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-vis spectra. The crystallite size was calculated to be around 30 nm by using the well- known Scherrer equation with the peak corresponding to (111) plane. The Raman peak at 306 cm^-1 is assigned to the A₁ mode of the CuAu ordered CuInS₂ . Thus, metastable cubic zinc blende structure would be evidenced. The absorption coefficient of the film has been found to be in the order of 10⁴ -10⁵ cm⁻¹, which make it promising for an intensive optoelectronic application. (author)