NOVELTY - An electrode layer (1000) is formed on a substrate. A thin layer of indium material and a copper material are sequentially formed on the electrode layer, to form a multilayered structure. The structure is subjected to thermal treatment process in an environment containing a sulfur-bearing species to form a copper-indium disulfide alloy material. The copper sulfide material is selectively removed from the alloy material, and a window layer is formed to obtain a thin-film photovoltaic device.    USE - Formation of thin-film photovoltaic device e.g. solar cell.    ADVANTAGE - The method uses a consumable material which facilitates adhesion between absorber material and electrode material for manufacturing high-efficiency thin-film photovoltaic cells.    DETAILED DESCRIPTION - An electrode layer is formed overlying the surface region of a transparent substrate. A thin layer of indium material is formed using a sputtering target of indium material, overlying the electrode layer to act as an intermediary glue layer to facilitate attachment to the electrode layer. A copper material is formed overlying the thin layer of indium material, and an indium layer is formed overlying the copper material to form a multilayered structure including the thin layer of indium material, copper material, and indium layer. The multilayered structure has thickness (I). The multilayered structure is subjected to thermal treatment process in an environment containing a sulfur-bearing species to form a copper-indium disulfide alloy material while consuming entire indium layer from at least the treatment process of the multilayered structure. The copper-indium disulfide alloy material has a copper-indium atomic ratio of 1.35:1-3:1. The copper-indium disulfide alloy material has thickness (II) of more than two times of thickness (I) of the multilayered structure. The entire thin layer of indium material is consumed into a portion of the copper-indium disulfide alloy material during the thermal treatment process, causing formation of a copper sulfide material overlying the copper-indium disulfide alloy material during the thermal treatment process. The copper sulfide material is selectively removed from the copper-indium disulfide alloy material, and a window layer is formed overlying the copper-indium disulfide material to obtain a thin-film photovoltaic device.    DESCRIPTION OF DRAWING(S) - The drawing shows a top view of the photovoltaic material.    Electrode layer (1000)