| 摘要 |
PURPOSE: To realize a printed circuit board, having an appropriate wiring capacitance at a desirable cost by a method, wherein there are provided on a surface a first region having first wiring density and a second region having a wiring density about four times higher than that of the first region as a sub-region. CONSTITUTION: A printed circuit board 1 is manufactured in an internal layer 7, having a conductive wire 2 having both structural external layer, and wiring density of the conductive wire 2 corresponds to wiring density of a first sub-region 4 and is greater than about 5 cm/cm<2> , and a thin film of a dielectric 8 is provided on a surface of the board 1, for example, in a sub-region 5. The entire surface is coated with a photoresist 9, is positioned, and is them exposed, so that the sub-region 5 is exposed and a hole 3 is bored to the conductive wire 2 through the dielectric 8 in the sub-region 5, and a thin metal layer 10 is formed by electrodeposition on the sub-region 5. Accordingly, if the sub-region 5 is coated and exposed using a mask and the metal layer 10 uncoated is removed, the wiring density of the sub-region 5 can be increased about four times more than that of the region 4. |
