Patent ID: 6518514
Filing Date: 2003-02-11
Classification: H05K,Y10T

Abstract:
A circuit board, comprising:not less than two wiring layers; an insulator layer for electric insulation between the wiring layers; and an inner-via-hole conductive member provided in the insulator layer in a thickness direction of the insulator layer for electric connection between the wiring layers, wherein: the insulator layer is made of a composite material containing an organic resin and a material having a smaller thermal expansion coefficient than that of the organic resin, and includes a surface part, a core part, and a surface part laminated in the stated order, each surface part having a higher content of the organic resin than the core part; the wiring layers have land portions on both sides of the insulator layer that are connected with the inner-via-hole conductive member and are embedded so as to be substantially in contact with both sides of the core part; and the inner-via-hole conductive member has a thickness substantially equal to a thickness of the core part.