Wiring substrate and method for manufacturing the same

A method for manufacturing a wiring substrate, comprising:

• forming a copper plating film on an entire surface of a substrate;
• forming a dry film resist layer on the copper plating film such that the dry film resist layer has a wiring pattern;
• forming a conductor layer on the substrate such that an upper surface of the conductor layer has a width that is equal to or larger than a width of a lower surface of the conductor layer and that the width of the lower surface is larger than a minimum width of a middle portion of the conductor layer between the upper surface and the lower surface;
• and
• removing the dry film resist layer from the conductor layer formed on the substrate,
• wherein the forming of the conductor layer includes etching the copper plating film formed on the substrate such that part of the copper plating film is removed and that the conductor layer comprising copper and having the wiring pattern is formed on the substrate.