Investigation of the effect of S/In molar ratio on physical properties of sprayed InS thin films.

Indium sulfide (InS) thin films have been synthesized on glass substrates using the spray technique (CSP). The S : In molar ratio was varied from 1 to 4 in the starting solution. The Raman analysis confirms the formation of the β-InS material and the absence of a secondary phase. The EDS analysis reveals that our layers are pure. The thin film surface is free of cracks, as observed in AFM images. Optical transmission achieved 80% in the visible and near infrared region. The refractive index () is affected by the changes in the S/In molar ratio. The optical parameters, single oscillator energy ( ), dispersion energy ( ) and high frequency dielectric constant ( ), are calculated the Wemple-DiDomenico model. In addition, the photoconductivity kinetics in InS films for S/In = 2 were investigated and analyzed. The - characteristics and the photoresponse were also studied.