WIRING BOARD

• Main Authors: MUTSUKAWA AKIO, TANAKA MASATO, KANEDA WATARU, SHIMIZU NORIYOSHI
• Format: Patent
• Language: English; Japanese
• Published: 04.12.2014
• Subjects: CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS; PRINTED CIRCUITS

PROBLEM TO BE SOLVED: To provide a wiring board which can achieve high density of a wiring layer.SOLUTION: A wiring board 1 comprises a core layer 11, a first insulation layer and a second insulation layer which are laminated on one surface side of the core layer, and a third insulation layer and a solder resist layer 40 which are laminated on the other surface side of the core layer. Each of the first insulation layer and the second insulation layer includes a plurality of insulation layers, a first wiring layer is formed between the first insulation layers, and a second wiring layer is formed on a surface where the second insulation layers are laminated. The first insulation layer and the third insulation layer are composed of a thermosetting resin and the second insulation layer and the solder resist layer 40 are composed of a photosensitive resin. In each of the first insulation layer and the second insulation layer, via wiring is embedded, and one end face of the first via wiring embedded in the top layer of the first insulation layer is exposed from a surface where the second insulation layer is laminated and directly connected to the second wiring layer. The surface of the first insulation layer, where the second insulation layer is laminated is a polished surface and the wiring density of the second wiring layer is formed higher than the wiring density of the first wiring layer. 【課題】配線層の高密度化を実現可能な配線基板を提供する。【解決手段】配線基板１は、コア層１１と、コア層の一面側に積層された第１絶縁層及び第２絶縁層と、コア層の他面側に積層された第３絶縁層及びソルダーレジスト層４０とを有し、第１絶縁層及び第２絶縁層は各々複数の絶縁層を備え、第１絶縁層間には第１配線層が形成され、第２絶縁層が積層された面には第２配線層が形成され、第１絶縁層及び第３絶縁層は熱硬化性樹脂からなり、第２絶縁層及びソルダーレジスト層４０は感光性樹脂からなり、第１絶縁層及び第２絶縁層にはビア配線が埋設され、第１絶縁層の最上層に埋設された第１ビア配線の一方の端面は、第２絶縁層が積層された面から露出し、第２配線層と直接接合されており、第１絶縁層の第２絶縁層が積層された面は研磨された面であり、第２配線層は、第１配線層よりも配線密度が高く形成されている。【選択図】図１