Earth-abundant non-toxic Cu2ZnSnS4 thin films by direct liquid coating from metal-thiourea precursor solution

A simple process for deposition of pure CZTS films from a methanolic solution of metal-thiourea complex is described. The precursor films are thermolysed at 200 degrees C in air for 10 min. Formation of kesterite CZTS is confirmed by X-ray diffraction (XRD). The films have grains of 100-200 nm and rms roughness of 1-2 nm. The energy band gap of CZTS films is 1.4 eV and is p-type in nature with electrical conductivity of 0.5 S/cm and thermo electric power coefficient of 86 mu V/K. The films are photoconducting. (C) 2012 Elsevier B.V. All rights reserved.