The effect of secondary phases on Cu2ZnSn(S,Se)4 based solar cell

The highest efficient Cu
₂
ZnSn(S,Se)
₄
(CZTSSe) Solar cell have a Cu-poor and Zn-rich metal ratio compared to the stoichiometry. Therefore secondary phases, such as Zn(S,Se), are formed. To investigate a possible correlation between these secondary phases and the solar cell properties, four samples were prepared which have efficiencies of 4.85-6.27%. In the semiconducting CZTSSe films, different amounts of Zn(S,Se) and SnSe
₂
are observed, and a correlation with solar cell properties is found. From the experimental results, conclusions about the influence of secondary phases on the cell efficiency are obtained.