MULTILAYERED CIRCUIT BOARD WITH THROUGH-HOLE CONDUCTIVE PART AND MANUFACTURE OF THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a multilayered circuit board with a through-hole conductive part in which connection between an inside copper foil circuit pattern and a through-hole conductive part can be surely and simply made. SOLUTION: Copper foil circuit patterns 2a-2e are laminated through insulating layers 3a-3d so that a multilayered circuit substrate material can be prepared. A main through-hole 5a put through the central part of land parts 4a and 4e of outside copper foil circuit patterns 2a and 2e of the multilayered circuit substrate material and the central part of a land part 4c of an inner copper foil circuit pattern 2c is formed at the multilayered circuit substrate material. Auxiliary through-holes 5b... laminated with the main through hole 5a, and put through land parts 4a, 4c, and 4e are formed by the irradiation of laser beams. Conductive paste is packed in a through-hole 5 constituted of the main through-hole 5a and the auxiliary through holes 5b, and then the conductive paste is burnt so that a through-hole conductive part 6 can be formed.