| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a wiring board which can achieve high density of a wiring layer.SOLUTION: The present wiring board comprises: a first wiring layer; a first insulation layer which is formed to cover the first wiring layer and composed of a thermosetting resin; first via wiring which is embedded in the first insulation layer and in which via holes each having one end face exposed from a top face of the fist insulation layer is filled with metal; a second wiring layer which is formed on the top face of the first insulation layer and on the one end face of the via hole and connected with the first wiring layer through the first via wiring; and a second insulation layer which is formed on the top face of the first insulation layer so as to cover the second wiring layer and composed of a photosensitive resin. Both of the top face of the first insulation layer and one end face of the first via wiring are polished faces and the one end face of the first via wiring is directly bonded with the second wiring layer. The second wiring layer is formed to have a wiring density higher than that of the first wiring layer and an electronic component mounting surface is formed on the side where the second insulation layer is formed.</p> |
