Recently the films of solid solutions CuZnSn(S Se) (CZTSSe) are used as the light absorbing layers in the thin film solar elements. The CZTSSe films are the Cu(In, Ga)Se analog, but do not contain rare and expensive In and Ga elements. In this study the CZTSSe absorbing films have been grown by a two-step process. At the first step the electrochemical deposition of the Cu, Zn, Sn and S components on the Mo coated glass has been performed. At the second step the annealing in the Se(S) atmosphere under the N flow has followed. It has been shown that the phase composition and structure of the synthesized CZTSSe thin films are strongly dependent on their elemental composition and processing regimes. The CZTSSe polycrystalline thin films of tetragonal structure, containing kesterite and stannite phases with the band gap energies 1.36 and 1.48 eV , have been obtained. The investigation of CZTSSe films by Raman spectroscopy confirms the formation of CZTSSe solid solutions with a two-mode character of vibrations for films, containing more than 30 at% sulfur. The preliminary results demonstrate the applicability of the proposed approach for producing the CZTSSe absorber for thin film solar cells.
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