LAUSR

Abstract Cations substitutions are known to make much significant contribution on achieving the high-quality kesterite Cu2ZnSn(S,Se)4 thin films. And the optimal ratios of Mn, Ni and Co substitutions are reported to be ~0.05, belong to the low doping to reduce their defect density, which looks like to some extent the effect of Na doping. In this study, learning the research experience of alkali metal doping, we introduced the extra trace Mn2+ ion into the precursor solution without affecting the compositions of other elements (i.e. Cu, Zn, and Sn), and the effect of trace addition on properties of the absorber layer was also studied. It was discovered that crystalline, electrical properties, and hole carrier concentration of Cu2ZnSn(S,Se)4 thin films increased with an increase of Mn incorporation, and the best doping ratio of Mn/(Cu + Zn + Sn) was considered to be 0.03. In addition, the effect of extra trace Mn-doping on the film thickness and elemental compositions of Cu2ZnSn(S,Se)4 absorber layer were studied in detail.