Patent ID: 6518672
Filing Date: 2003-02-11
Classification: H01L,H05K

Abstract:
A multi-layer wiring substrate comprising:a plurality of wiring substrates, each of said substrates comprising a plate or sheet-like insulating layer and a wiring layer formed on only one of the surfaces of the insulating layer; said plurality of wiring substrates being laminated in such a manner that said insulating layer and wiring layer are alternately arranged; at least a pair of said wiring layers arranged on respective surfaces of the insulating layer being electrically connected with each other by means of connecting portions formed so as to pass through said insulating layer; and said connecting portion comprising a part of wiring of said wiring layer, which is extended into a region of an opening, formed so as to pass through said insulating layer, so that only said part of wiring being formed as an extension and a low melting point metal disposed in said opening and electrically connecting said extension of the wiring layer with a wiring substrate formed on an adjacent insulating layer of the laminated structure.