| 摘要 |
PURPOSE:To make it possible to form a uniform connecting hole for wiring and also to reduce reject by pinhole, by forming a photoresist layer on a conductor pattern on a thermal-resistance insulating substrate. CONSTITUTION:After coating a photoresist 3 on a thermal-resistance insulating substrate 1 on which a conductor pattern 2 is formed, the photoresist on other sections than a joint of a top layer conductor is removed. And then, on the entire surfaces of the substrate 1 and the resist 3, an insulating paste 4 is printed and drived. A photoresist 5 is coated on surface of the paste 4, the resist 5 on the joint of the top layer conductor is selectively removed and, at the same time, the paste 4 is removed from this section, and by doing so a connecting hole 6 is formed. In this case, because of existence of the resist 3, excessive removal of the paste 4 is prevented and a uniform hole 6 is formed. And, at the same time, an insulation layer can be prevented from becoming a reject due to pinhole problem. And then, the substrate 1 is baked at a high temperature to incinerate the resists 3 and 5 and the paste 4, and as a result, an insulating layer 7 is formed with a hole 6 connected to the top layer conductor. |
