CORE SUBSTRATE,AND MULTILAYER CIRCUIT BOARD USING IT

摘要

A core substrate (B) being used when a multilayer circuit board is produced by laying a plurality of unit circuit boards on the upper and lower surfaces in which two insulation layers (10A, 10B) are laid while holding a conductor land part (11A) between them, a pair of holes (12A, 12B) are made by laser machining above and below the conductor land part while extending from the surface of the insulation layer to the conductor land part and filled with a electroplating material thus forming a pair of columnar conductors (13A, 13B) being connected electrically through the conductor land part. Since all layers can be interconnected through a series structure formed of an electric copper plating material, the core substrate is useful for producing a multilayer circuit board in which low resistance and fine patterning can be realized.