Deposition of Cu2ZnTi(S:Se)4 absorber layer by sputtering methods and their usage in the fabrication of solar cells

Photovoltaic (PV) cell production is an area where value added is high and innovation and development activities are intense. Triple polycrystalline chalcopyrites such as CuInSe2 (CIS) and Cu (In,Ga)Se2 (CIGS) are very popular as thin film solar cells with up to 20% efficiency. CIGS based commercial thin film solar cells are limited in practice due to the low availability of In and Ga elements and high prices. Therefore, it has become obligatory to replace the rare elements in nature with those that are easily provided. For this purpose, solar cells have been developed using Cu2ZnSnS4 (CZTS) and similar thin films which do not contain high cost elements such as In and Ga. Cu2ZnTi (S:Se)4 (CZTiS:Se) is a promising material that can be used as an alternative compound due to its direct bandwidth of 1.04 eV and its high absorption coefficient (104 cm-1). CZTiS:Se does not contain rare and expensive elements and therefore has the potential to be used in low priced commercial systems. In recent years, CZTiS thin film production and the studies on the production of these cells with the solar cells have been done. In this study, in order to use CZTiS:Se thin films more effectively in PV systems, using the reactive magnetron co-sputtering method, CZTiS:Se films were formed on glass, and the structural, electrical and optical properties of the films were investigated. The morphological, optical, electrical, temperature dependent conductivity, photoconductivity and structural properties were investigated using SEM-EDS, UV-VIS data, Hall Effect, XRD and Raman spectroscopy methods. By using CZTiS: Se thin films whose optical, electrical and structural properties have been determined, solar cells have been formed and the electrical and photovoltaic properties of these cells have been examined and the effect of these thin films on PV performance has been investigated. In conclusion, it has been shown that CZTiS:Se thin films can be an alternative absorber layer in conventional CIGS and CZTS based solar cells.