Growth characterization of CZTS based thin films grown by elektrochemical growth technique

In this work, CZTS thin films was grown on ITO by electrochemical deposition technique using copper (II) sulfate pentahydrate (CuSO_4.5H_2 O), zinc (II) sulfate heptahydrate (ZnSO4.7H2O), tin (II) sulfate (SnSO_4) and as a sulfur source sodium thiosulfate (Na_2 S_2 O_3) in DI water. In order to obtain optimum film characteristics, growth parameters was changed; between 4,50 - 6,30 for pH; -1,0 and -1,50 V for potential and at the temperature 〖25〗^0 C. The best quality CZTS thin filmshave been obtained from 0,02 M copper (II) sulfate pentahydrate( CuSO_4.5H_2 O), 0,01 M zinc (II) sulfate heptahydrate (ZnSO4.7H2O), 0,02 M tin (II) sulfate (SnSO_4), 0,02 M sodium thiosulfate (Na_2 S_2 O_3), 0,1 M tartaric acid (C_4 H_6 O_6) and 0,2 M (Na_2 C_6 H_5 O_7.2H_2 O) within DI water of 〖25〗^0 C for one hour, at the pH=5,70 and V=-1,05 V. It was observed from the XRD measurements that the CZTS thin films grown by elecyrochemical deposition were in polycrystal from having the (211) preferred orientation. The band gap values of the optimum CZTS thin films were measured as 1,6 eV from the absorption measurements. The atomic force microscopy (AFM) measurements showed that the average roughness value of the surfaces of CZTS films obtained by electrochemical deposition technique was around of 41 nm. We investigated the thickness and structure of thin film with Scanning Electron Microscope (SEM).