WIRING BOARD, SEMICONDUCTOR DEVICE AND WIRING BOARD MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a wiring board which can inhibit separation of an insulation layer but correspond to refinement of a wiring layer.SOLUTION: A wiring board 10 has a wiring structure 11 having an insulation layer 35 and via wiring 36, and a wiring structure 12 laminated on a top face of the wiring structure 11. The wiring structure 12 has a wiring layer 50 formed on a top face 35A of the insulation layer 35 and an upper end face 36A of the via wiring 36. The wiring structure 12 has: a plane layer 60 which has a plurality of through holes 60X which penetrate in a thickness direction and in which at least a part thereof is formed in a lattice shape in plan view and which is laminated on the insulation layer 35; and an insulation layer 51 which is laminated on the insulation layer 35 and fills the through holes 60X and covers the plane layer 60 and the wiring layer 50. A wiring density of the wiring structure 12 is higher than a wiring density of the wiring structure 11. Each through hole 60X is formed in a manner such that an opening width of an upper opening end is narrower than an opening width of a lower opening end.