MANUFACTURE OF MULTILAYERED PRINTED WIRING BOARD

摘要

PURPOSE: To easily form a via hole by removing a conductive film which connects the plated through hole of a multilayer printed wiring board to the outermost circuit pattern of the wiring board by forming a recessed section facing the opening of the plated through hole. CONSTITUTION: A multilayer printed wiring board is formed by overlapping a prepeg 12 between printed boards 14a and 14b carrying circuit patterns L1-L4 and sticking the boards 14a-14b to the prepreg 12 by thermocompression bonding. Then a plated through hole 3 is formed by forming a through hole 15 through the wiring board with a drill and plating 10 the internal surface of the hole 15. Thereafter, a conductive film 4 which electrically connects the through hole 3 to the outermost circuit pattern 5 is removed by forming a recessed section 1 facing the opening 2 of the through hole 3.