Cu(In,Ga)Se_2 Thin-Film Evolution During Se/Ar atmosphere Selenization of Sputtered Metallic Cu-In-Ga Precursors

摘要

The dependence of surface morphology and structure properties of Cu(In,Ga)Se_2 films on the substrate temperature profile is investigated using selenization of sputtered metallic Cu-In-Ga precursors at low pressure of Se/Ar atmosphere. The samples were characterized by means of X-ray fluorescence,X-ray diffraction and Scanning Electron Microscope. It is found that the formation of volatile In selenides during selenization process result in loss of In. It indicates that the surface of the sample b has many voids and the Cu/(In+Ga) ratio changes from slightly In-rich to Cu-rich side. No diffraction reflections of In_2Se_3 are observed in this low pressure selenization process. The homogenized quaternary Cu(In,Ga)Se_2 film are obtained at higher temperature through diffusion-controlled reaction.