PURPOSE: To form a bubble-free oxygen barrier film by subjecting a resist layer to X-ray irradiation through a specific resin layer.

CONSTITUTION: The oxygen barrier film which has no air bubbles, etc., can be formed by coating the layer consisting of the resin such as polyvinyl pyrrolidone or pullulan which is not crosslinked by X-ray irradiation and does not generate an insoluble intermediate interposing layer by dissolving with the underlying resist layer with each other on the resist layer. Degradation in resolution is thereby enabled. For example, CMS chloromethylated polystyrene which is a negative type resist is spin-coated on a substrate 22 consisting of a silicon wafer, etc., and is then prebaked. The polyvinyl pyrrolidone PVP which is a water soluble high polymer is then spin-coated on the resist layer 23 consisting of the CMS and thereafter, the coating is baked. The PVP layer 24 to serve as the oxygen barrier film is thereby formed on the resist layer 23. The X-rays of the prescribed pattern formed by a mask 15 are projected through this PVP layer 24 to the resist layer 23.