CZTS thin films on transparent conducting electrodes by electrochemical technique

Abstract

We have fabricated single phase Cu 2ZnSnS 4 (CZTS) films using a specially designed 3-stage electrochemical system. Sequential electrodepositon of constituent metallic layers was carried out on SnO 2/F coated glass substrates using a platinum counter electrode and a saturated calomel reference electrode. Unique bath compositions were formulated for each of these constituents. Sequentially deposited tri-layer stacks were annealed in sulfur environment to get CZTS phase. Detailed structural, morphological and optical characterization experiments were performed using several techniques including x-ray diffraction, Raman and UV–visible spectroscopy, scanning electron microscopy and atomic force microscopy. All characterization experiments indicated that the films are single phase with a measured direct band gap of 1.5 eV.