MANUFACTURE OF PRINTED CIRCUIT BOARD, WIRING FORMING METHOD AND WIRING MODIFYING METHOD THEREFOR, AND WIRING-MODIFICATION AIDING APPARATUS

摘要

PROBLEM TO BE SOLVED: To obtain easily and with a high yield a printed circuit board, having vertical wirings with a high mounting density and respective high aspect ratios. ;SOLUTION: A wiring modifying method consists of a step for forming a first resist layer 21 to cover therewith a second resist layer 16 (b, c), a step for projecting thereafter a laser beam on the first resist layer 21 present over each second through, hole 19 with an incompletely filled conductor (d), a step for decomposing and removing thereby the first resist layer 21 and forming each first through-hole 19b reaching the second through-hole 19 (e), and a step for filling the conductor into the second through-hole 19, opened via the first through-hole 19b to form each vertical wiring 23.;COPYRIGHT: (C)1998,JPO