| 摘要 |
PURPOSE:To perform easily amendable and high-speed and high-density mounting by a method wherein wiring patterns for amendment are provided in 45 deg. direction to a side and the end sections are exposed to the surface of a substrate in a multilayer wiring substrate having wiring patterns running in parallel and at right angles to one side of the substrate. CONSTITUTION:Multilayer wirings 21, 22 are crossed at right angles respectively and wiring patterns 31 for amendment are provided in 45 deg. direction to the multilayer wirings 21, 22 and pads 32 are made by exposing the end sections of the patterns 31 to the regions except pads 42 for LSI adhesion and pads 41 for LSI connection on the substrate surface. For example, a recessed section is formed at the region corresponding to an insulating layer 23 and pads 32 are formed on the same plane as the patterns 31. With each pad 32 or each pad 41 connected, amendment is completed by a few externally mounted wirings 33 as the wirings 33 are formed with high density. Therefore, the mounting density of LSI does not decrease and amendment wirings and substrate wirings form at 45 deg. and there are a few paralleled section. Thus, signal leakage is extremely small. |
