SEM analysis and selenization of Cu-Zn-Sn sequential films produced by evaporation of metals

The formation of Cu2SnZnSe4thin films in the selenization of different sequential metallic and alloy films is investigated. It is shown that the main process of low temperature selenization (up to 300degC) is the formation of different binary copper selenides on the layer surface. High temperature selenization (over 400degC) leads to the formation of Cu2ZnSnSe4phase with some excess of a separate ZnSe phase. The content of ZnSe diminishes with the rise of the selenization temperature, but the selenized films stayed always multiphased. The size of the formed Cu2ZnSnSe4crystals is controlled by the composition of the precursor.