A light weight and a low cost EL display device is provided, in which light emitting elements are formed on a flexible film. A thin metallic substrate is used as an element forming substrate with the present invention, edge portions of the metallic substrate are bent, and the metallic substrate is attached with good adhesion, within a vacuum, to a substrate holder which possesses curvature in its edge portions. After then forming light emitting elements on the thin metallic substrate, the substrate holder is separated.