Patent ID: 8935851
Filing Date: 2015-01-20
Classification: B32B,H05K,Y10T

Abstract:
1. A method of manufacturing a circuit board, comprising the steps of: forming a core material by attaching a copper foil having a thickness of 9 μm or more and 18 μm or less on both surfaces of a prepreg while subjecting the prepreg with the attached copper foil to an elevated temperature, the prepreg being formed by impregnating carbon fiber cloth made of a pitch-based fiber with a resin which contains an elastomer component and in which an elastic modulus when cured is 3 GPa or less; forming a first through hole in the core material; forming a first conductive film on an inner wall of the first through hole; forming an insulating layer on both surfaces of the core material and in the first through hole; forming a second through hole in the insulating layer in the first through hole; forming a second conductive film on an inner wall of the second through hole; and forming, on surfaces of the insulating layers formed on the both surfaces of the core material, a circuit layer electrically connected to the second conductive film.