| 摘要 |
PURPOSE:To acquire adequate insulating resistance on a surface by forming a polyimide resin insulating layer on an alumina board at first and by forming a metal thin film thereon. CONSTITUTION:After an insulating layer 5 having a polyimide resin via hole 4 is formed on an alumina ceramic multilayer wiring board 1, a metal thin film 2 is formed thereon by deposition or sputtering. A photo resist 3 is formed thereon, a wiring pattern is formed by photolithography and a wiring layer 6 is formed by plating method on a wiring pattern 7. Thereafter, the photoresist 3 is peeled off and the metal thin film 2 is etched by an ion beam etching device. Thereby, generation of insulation resistance defective caused by etching residue is eliminated since a surface of polyimide resin is fully smooth compared with alumina ceramic. |
