| 摘要 |
PURPOSE:To form a conductor part of high pitch accuracy by forming a wiring part to electrically connect conductor part and a via-hole, on the main surface of a multilayer ceramic substrate, by applying thin film wiring technique. CONSTITUTION:On the surface of a multilayer ceramic substrate 2. thin films composed of Ti, Mo, and Cu are formed in order, on which electrolytic plating 7 of Cu is performed. Photoresist 8 is spread on the plating 7, and unnecessary parts of the photoresist are eliminated by processes of pattern exposure and development. Unnecessary parts of the thine film are eliminated by etching process. Thus the following are formed by the thin film 6; a conductor part 9, the cover pad 10 of a via-hole 4, a wiring part 11 to electrically connect the conductor pad 9 and the via-hole 4, and the junction surface of a heat sink 12. As a result, forming the conductor part of high pitch accuracy is enabled without the influence of irregularity of shrinkage factor at the time of baking a green sheet. |
