Study on formation and characterization of kesterite CZTSSe thin films deposited by thermal evaporation technique for solar cell applications

In last few years, CZTSSe has shown promising characteristics, material properties and better efficiencies for the application in solar cell. In this paper, various structural and optical properties of CZTSSe have been studied. Cu 2 ZnSn(S 0.8 Se 0.2 ) 4 was synthesized using melt quench technique and deposition of thin films was done using thermal evaporation technique. X-ray diffraction (XRD), Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy and Raman spectroscopy were used for the characterization of the material to investigate the composition, morphological and structural properties. XRD and Raman studies suggest that CZTSSe samples have attained pure kesterite phase. The microstructural properties such as crystalline size, lattice constants and lattice strain have been analysed which confirm tetragonal unit cell structure. Moreover, the result of SEM shows good morphological properties of the material. Further analysis of optical properties suggests that prepared CZTSSe sample has high absorption coefficient of the order of 10 4 cm −1 and calculated value of the optical bandgap is 1.42 eV, which are in desirable range and make the material suitable for solar cell applications.