METHOD OF MANUFACTURING WIRING BOARD

摘要

PROBLEM TO BE SOLVED: To form a fine wiring layer on an insulating layer with good adhesion in a method of manufacturing a coreless type wiring board.SOLUTION: A method of manufacturing a wiring board comprises the steps of: forming a build-up intermediate 5 composed of n layers (n is an integer of 2 or more) on a support 10 via an etching stop layer 12; removing the support 10 to expose the etching stop layer 12; removing the etching stop layer 12 to expose a lowermost wiring layer 21; forming second insulating layers 35 and 36 on both surfaces of the build-up intermediate 5; forming via holes VH5 and VH6 reaching wiring layers 21 and 25 in the insulating layer 35 and 36 on both surface sides, respectively; roughening an exposed surface of the insulating layer 36 covering the wiring layer 21; and forming a wiring layer 27 connected to the wiring layer 21 via the via hole VH6 on the exposed surface of the insulating layer 36, and forming a wiring layer 26 connected to the wiring layer 25 via the via hole VH5 on the insulating layer 35.