US Patent 8413321 Module substrate and production method

A module substrate includes a multilayer substrate that includes a plurality of layers, a bottommost of the layers being a ceramic layer. Solderable contacts, which include fired pads composed of a conductive paste, are applied to the bottommost ceramic layer. A covering layer overlies the pads. The covering layer covers all outer edges of the pads. A window is cut out of the covering layer. A metallic coating is applied to each pad exclusively within the window.