A laminating step includes a second step of laminating a second insulation layer on a conductive pattern last formed at a first step, roughening the surface of the laminated second insulation layer excluding a desired area, and forming a conductive layer on at least the desired area of the surface of the second insulation layer, and a processing step includes a removing step of removing an upper part of the area higher than the second insulation layer on the substrate obtained at the laminating step, and an exposing step of exposing a part of the area of a conductive pattern adjacent to the lower side of the second insulation layer.