| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of producing a multilayer circuit board which uses a build-up layer formed by connection using conductive protrusions as a cable, and to provide a circuit base material suitable for the multilayered circuit board. SOLUTION: In a method of producing the multilayer circuit board, the circuit base material which has metal foil 2 having conductive protrusions 1 erected at least on one of its surface and an insulation resin layer 3 laminated to the one surface of the metal foil and fixed with the conductive protrusions extending therethrough is laminated with another circuit member, and circuit layers are connected with one another by the conductive protrusions. The insulation resin layers having a multilayered structure is formed by coating and drying a resin layer one by one on one surface of the metal foil. One of the insulation resin layers is a polyamic acid being a polyimide precurser when laminated. After laminating, imidizing is performed to form a polyimide resin layer. COPYRIGHT: (C)2008,JPO&INPIT |
