Patent ID: 8153909
Filing Date: 2012-04-10
Classification: H05K,Y10T

Abstract:
1. A multilayer wiring board, comprising: a laminated structure in which conductor layers, at least one inner insulating layer, and at least one outer insulating layer are alternately laminated into a multilayer, the at least one inner insulating layer containing a fiber material in a polymeric material, the at least one outer insulating layer not containing the fiber material, the at least one inner insulating layer and the at least one outer insulating layer having a plurality of via holes penetrating therethrough, the plurality of via holes having respective diameters increasing in a same direction, and a plurality of filled via conductors formed in the via holes respectively for electrically connecting the conductor layers, wherein a tip of the fiber material protruded from an internal wall surface of each of the via holes of the at least one inner insulating layer cuts into a respective sidewall of each of the filled via conductors of the at least one inner insulating layer.