A simple route for synthesis of copper iron tin sulfide thin films

Abstract

Copper iron tin sulfide Cu2FeSnS4 (CFTS) thin films are prepared by a facile and low-cost route using sol-gel spin-coating method without a sulfurization step. The optimal condition for synthesis of CFTS thin films has been determined. X-ray diffraction and Raman spectroscopy analysis revealed that the formation of a pure phase of CFTS thin films at 400 °C for 40 min with a large crystallite size 60 nm. The morphological and chemical composition study indicates the formation of uniform, smooth, cracks free and nearly stoichiometric thin films. The films show p-conductivity, good optical and electrical properties; high absorption coefficient >104 cm−1 in visible region, band gap energy of about 1.5 eV, carrier density of 3.85 1016 cm−3 and low resistivity of 0.364 Ω.cm. The obtained physical properties of CFTS thin films are suitable for solar cell applications.