Structural and Optical Properties Study of SnS: Ag Doped Cu Thin Films Prepared by PLD Technique for Solar Cell Application

Abstract

Cu-doped SnS: Ag thin films have been fabricated by the PLD technique to modify specific properties of SnS films for a promising approach to reduce theantisite defects and further improve the efficiency of choosing the optimum condition to fabricated SnS: Ag solar cell by doping with different ratios of Cu deposited on Si wafers. A significant effect of the Cu doping ratio is noticed on the XRD pattern and optical properties of prepared thin films.The results of XRD show the polycrystalline nature of the prepared SnS powder and broad lines for thin films as its nanocrystalline structure. Additional phases appeared corresponding to Ag and Cu at a high ratio.  The crystallite size reduced from 15.4 to12.8 nm after doping with 0.05 Cu and increased up to 14.7 with an increasing Cu ratio to 0.15 while the lattice strain has the opposite behavior. The optical absorbance increases for the SnS: Ag sample and more increasing with the Cu content. A red shift in the band edge with Cu doping appeared.  The band gap reduced from 2.2 eV for SnS to 1.75 eV for (SnS:Ag)0.85Cu0.15.