| 摘要 |
PROBLEM TO BE SOLVED: To provide a multilayer wiring board, in which a fine conductor circuit layer of metal foil is prevented from short-circuiting through deformation of resin, when the multilayer wiring board is produced by a transfer method. SOLUTION: The multilayer wiring board comprises an insulation layer, composed of a composite material of a heat resistance cloth 1b and thermosetting resin 1a, a conductor circuit layer 5 comprising a plurality of layers formed on the surface of the insulation layer and between the insulation layers, and a plurality of via hole conductors 4 formed by filling the via holes with metallic powder. The conductor circuit layer 5 is embedded in the surface of the insulation layer 2 and has a surface roughness (Rz) of 2-8μm on the side which is being embedded in the insulation layer 2. The thickness of the conductor circuit layer 5 is larger than thickness L of a thermosetting resin layer 3, extending from the heat resistance cloth 1b of the insulation layer 2 to the surface thereof and protruding, and recessed parts on the surface of the conductor circuit layer 5 side are embeddedly engaged, protruding and recessed parts of the heat resistance cloth 1b. |
