| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing a high density build-up printed wiring board, in which a via hole and a conductor circuit can be formed in the same step and the insulation between circuits be secured without plating resist. SOLUTION: In this method for manufacturing a highly dense build-up printed wiring board, a mask film 30 having a part with different light transmissivities corresponding to the position and depth of the respective parts of a pattern which is formed relating to the inner layer circuits 11, 12 and 13 of an inner layer printed wiring board 10, is placed on a photosensitive resin layer 20 formed on the board 10, and it is exposed and developed to form a build-up resin layer. In addition, in a palladium layer 40 as a catalyst layer formed on the build-up resin layer, the heighest part in the resin layer is surface-ground together with the palladium layer 40 up to a prescribed height, so that the highest part is left as an insulation area between circuits and the circuits are electrically isolated. |
