Patent ID: 8895868

Claim:
A wiring substrate comprising; a wiring layer including a non-electrolytic plating layer formed by non-electrolytic plating and an electrolytic plating layer formed by electrolytic plating stacked directly on the non-electrolytic, plating layer the wiring layer being made of copper; a silicon substrate having a first surface and a second surface, said silicon substrate having a through hole, said through hole being formed so as to penetrate the silicon substrate from the first surface toward the second surface; a through electrode made of copper filled into the through hole; an insulating layer made of silicon dioxide and arranged adjacent to the through electrode, said insulating layer being directly stacked on the silicon substrate and covering the first surface and the second surface of the silicon substrate and an inner wall surface of the through hole, and wherein a side surface of the through electrode is in contact only with the insulating layer; and, an adhesive layer made of titanium, said adhesive layer formed only outside the through hole directly on a surface of the insulating layer and formed on at least one of the first surface and second surface of the silicon substrate, wherein the insulating laver, the adhesive laver, the non-electrolytic plating layer, and the electrolytic plating layer are formed and arranged on the silicon substrate in this order, the electrolytic plating layer is stacked directly on an end surface of the through electrode, the wiring layer is made on at least one of the first surface and the second surface of the silicon substrate via the adhesive layer and the insulating layer, the insulating layer and the wiring layer are stacked with the adhesive layer interposed between the insulating layer and the wiring layer, the non-electrolytic plating layer is stacked directly on the adhesive layer, and the non-electrolytic plating layer and the adhesive layer are formed only directly below the electrolytic plating layer, and the through electrode and the wiring layer are stacked in contact with each other.