Study of sprayed CZTS thin films containing various copper content

Abstract

By ultrasonic spray, we have deposited CZTS films on Mo coated substrates. A sulfurization treatment was systematically performed under Argon atmosphere at 500 °C for one hour. Copper content effect of CZTS thin films of about 1 µm was studied by X-ray diffraction, Raman spectroscopy and optical transmittance measurements. The films exhibited the kesterite structure despite the appearance of some secondary phases for a high and poor copper content. The gap energy value was sensitive to the copper content and ranged between 1.42 eV and 1.68 eV.