硫代硫酸钠浓度对电沉积制备铜锌锡硫硒薄膜性质的影响(英文)

Effect of Na_2S_2O_3·5H_2O concentration on the properties of Cu_2 ZnSn(S,Se)_4 thin films fabricated by selenization of co-electroplated Cu-Zn-Sn-S precursors

采用后硒化Cu-Zn-Sn-S电沉积预制层的方法制备了铜锌锡硫硒薄膜,其中Cu-Zn-Sn-S预制层是通过含有不同浓度的硫代硫酸钠电解液电沉积而成的.实验发现,硒化前后薄膜的性质与硫代硫酸钠浓度密切相关.SEM,EDS,XRD,Raman和透射光谱分析表明,当硫代硫酸钠的浓度为5 mM时,沉积的薄膜形貌平整,晶粒明显,组分贫锌,具有单一的铜锌锡硫硒结构,且其带隙为1.11 eV;在浓度高于5 mM下沉积的薄膜形貌粗糙并产生杂相硒化锡;在浓度低于5 mM下沉积的薄膜组分严重贫锌并生成大量的Cu2SnSe3.

Cu2ZnSn( S,Se) 4 films were fabricated through post-selenization of Cu-Zn-Sn-S precursors co-electroplated by varied Na2S2O3·5H2O concentrations. The property of obtained films before and after selenization shows a close dependence on the concentration of Na2S2O3 ·5H2O. Only the film grown by 5 mM of Na2S2O3 ·5H2O shows a uniform surface with faceted grains,a Zn-poor composition,a single phased Cu ZnSn( S,Se)4 structure and a 1. 11 eV band gap evidencing by SEM,EDS,XRD,Raman and transmittance spectra. More than 5 mM of Na2S2O3 ·5H2O additive to the electrolyte yielded the films with rougher morphology and the presence of SnSe x. Less than 5 mM of Na2S2O3 ·5H2O additive to the electrolyte resulted in the films with highly Zn-poor content and the primary formation of Cu2SnSe3. Key words: Cu2 ZnSn( S,Se) 4 thin film,Na2S2O3 ·5H2O concentration,co-electroplating,selenization