Solar Energy Materials and Solar Cells, Vol.101, 277-282, 2012
A two-step approach for electrochemical deposition of Cu-Zn-Sn and Se precursors for CZTSe solar cells
A two-step electrochemical route for fabrication of Cu-Zn-Sn (CZT) and Se precursors' layers for a thin film Cu2ZnSnSe4 (CZTSe) absorber for solar cells is demonstrated. The CZT was electrochemically co-deposited in a citrate solution and after that an appropriate amount of Se was electrodeposited on the top. The CZT+Se were annealed in Ar atmosphere using a slow or fast increase in temperature up to 500 degrees C. SEM with EDX. XRD and Raman spectroscopy examinations of precursors and of the manufactured CZTSe thin films were carried out. The XRD measurements indicated that the CZT precursor contained eta-Cu2.26Sn5, Sn and gamma-CuZn5 phases. The electrodeposited Se was polycrystalline with a hexagonal structure. The manufactured CZTSe in all the cases presented Cu2ZnSnSe4 with kesterite or partially disordered kesterite structure; however a purer CZTSe phase was formed using the fast increase in the annealing temperature. (C) 2012 Elsevier B.V. All rights reserved.