CIRCUIT FORMING BOARD PRODUCING METHOD, CIRCUIT FORMING BOARD, AND MATERIAL FOR CIRCUIT FORMING BOARD

摘要

A manufacturing method of a clad board includes: sticking a releasing film to a pre-preg sheet; forming a non-through-hole or through-hole in the pre-preg sheet including the releasing film; filling the hole with conductive paste; peeling off the film; and heating and pressing a metal foil onto the pre-preg sheet. The clad board has a smooth face formed on one face or both the faces of the pre-preg sheet, so that the conductive paste is restrained from spreading in an interface between the pre-preg sheet and the releasing film. This structure can avoid short-circuit between circuits and prevent insulating reliability from lowering. As a result, an yield rate is improved, and a reliable circuit board is obtainable. IMAGE