| 摘要 |
PURPOSE:To obtain a sheet type printed coil having an extremely high space factor, having high reliability in regard to electric connection between coil patterns on both sides of the surface and the back of an insulating layer, and moreover having superior mass productivity by a method wherein conductive metal layers are formed according to electroplating. CONSTITUTION:Conductive metal foils 5, 5' are adhered to both the sides of the surface and the back of an insulating layer 4 to form a substrate (s). A photo resist material is applied on the conductive metal foils 5, 5', and exposure and development are performed to form etching resist layers 6, 6' in the desired coil pattern type spirally on the conductive metal foils 5, 5'. Then conductive metal foil parts 7, 7' not adhered with the etching resist layers 6, 6' are etched to be removed according to an etching liquid to form the desired coil patterns consisting of the conductive metal foils 5, 5'. Then electroplating is performed to the substrate (s) formed with a penetrating hole 9 to form conductive metal plated layers 10, 10', 10'' on the coil pattern type conductive metal foils 5, 5' and on the inside wall surface of the penetrating hole 9. |
