Growth and characterization of spray deposited quaternary Cu2FeSnS4 semiconductor thin films

Quaternary stannite Cu2FeSnS4 thin films (CFTS) have been grown on well cleaned amorphous glass substrates at various deposition temperatures (175 degrees C-325 degrees C) by chemical spray pyrolysis. CFTS thin films have been characterized to examine the structural, morphological, compositional, optical and electrical properties. Tetragonal crystal structure has been confirmed from X-ray diffraction. Crystalline size was found to be 10-18 nm. Scanning electron microscopy showed monodisperse particles with hexagonal morphologies. Energy dispersive analysis by X-rays study confirmed stoichiometric deposition of CFTS thin films. The direct bandgap was found to be 1.54 eV for CFTS thin film deposited at 250 degrees C. It was observed that film resistivity drop at deposition temperature of 250 degrees C. The structural, morphological, compositional, optical and electrical properties of CFTS films have been found to be deposition temperature dependent. An appropriate optical band gap of 1.54 eV and a noteworthy and stable electrical property indicate their prospective for solar cell applications.