| 摘要 |
PURPOSE:To form a coil conductor, the thickness of a film thereof is uniform without depending upon the position of a metallic plate and a resistance value thereof hardly varies, by executing chemical plating before copper electroplating. CONSTITUTION:A glossy chromium plated plate is used, washed by a neutral detergent and nitric acid, washed by water, and untrasonic-cleaned in isopropyl alchohol and purified. The plate is dried, a negative type photo-resist is lined on the surface, ultraviolet rays are projcted by using a mask capable of projecting ultraviolet rays only to sections except a coil conductor, and a resist 2 is formed through a development in trichloroethane. A copper plated film 3' in approximately 1mum thickness is formed by using a copper chemical plating liquid. A coil conductor 3 is shaped through copper electroplating by an immersion in a copper sulfate plating bath. The film thickness of the obtained conductor is 80mum at a section such as the center of the metallic plate and is kept within a range of 80-85mum in the periphery, and a resistance value hardly varies. |
