| 摘要 |
PROBLEM TO BE SOLVED: To reduce poor insulation due to deposition of foreign substances on a mask and repairs therefor by laminating positive-type photosensitive resin layer and thermosetting insulating resin layer soluble to a developer. SOLUTION: On a circuit board, having a first wiring are laminated an insulating resin layer and positive-type photosensitive resin layer. After exposure to an active ray through a mask, shielding parts other than the inter-layer connection holes, inter-layer connection holes for a first circuit are opened by a developer. After developing the positive type photosensitive resin layer of the holes, this resin layer is used as an etching mask to develop the insulating resin layer. The positive-type photosensitive resin layer is then removed, such that the entire surface of this layer is again exposed to an active ray and developed to remove this layer. The insulating resin remaining on the first circuit board is hardened by light or heat and is plated with Cu. |
