STUDY OF Cu2ZnSnSe4 THIN FILMS PREPARED BY E-BEAM EVAPORATION OF SOLID-STATE REACTED COMPOUND

A quaternary semiconductor Cu2ZnSnSe4 (CZTSe) has been emerged as a paramount candidate in form of absorber layer in thin film solar cell. CZTSe holds additional advantages like non-toxic constituents, abundant in earth crust and low cost over other chalcogenides like CIGS, CdTe etc. In this paper we have reported the growth of CZTSe thin films using pre synthesized bulk CZTSe solid state reacted compound as a source in e-beam evaporation deposition technique. Firstly bulk CZTSe compound in five different ratios were prepared using elemental constituents of Cu, Zn, Sn and Se. These five solid state reacted compounds were used as a target for thin film deposition. The Cu/(Zn+Sn) ratio in these films vary nearly to stoichiometry. The structural result analysis carried out using XRD data of thin films confirmed that phase content was noticeably affected during the film deposition process with respect to Cu/(Zn+Sn) ratios variation. Some amount of secondary phases were also found in the samples. Compositional variation in elemental constituents was studied by SEM-EDX and mapping spectra.