The effect of binary sulfides precursors with different value states on CZTS thin films

摘要

In this work, Cu2ZnSnS4 (CZTS) thin film was successfully prepared from four types of mixed binary sulfides nanoparticles under inert Ar atmosphere. A comparison study was conducted to explore the effect of binary sulfides with different value states on the CZTS thin films. Through X-ray diffraction (XRD), Raman and scanning electron microscopy (SEM), the pure CZTS phase can be obtained independent of the value states. However, distinguished crystallinity and morphology_ of CZTS were_observed by using binary precursor with different value states. The grain size up to 1 pm was achieved by annealing (Cu2S + ZnS + SnS2) precursor without additional sulfur atmosphere, suggesting that value state of binary sulfides precursor play an important role in CZTS growth. This result also agrees well with our theoretical prediction. Finally, appropriate ratio of Cu/Zn/Sn was evidenced to yield an enhancement in power conversion efficiency from 0.09% (stoichiometric ratio) to 0.55% (Cu-poor, Zn-rich).