| 摘要 |
PURPOSE:To fully protect a polyimide layer against runaway, sinking, or the like so as to protect a ceramic board against insulation defects by a method wherein metal oxide powder excellent in wettability to polyimide is forced into the cutout of a via, then a corrective layer is formed, and a polyimide coating is provided. CONSTITUTION:Metal oxide powder is uniformly sprinkled on a base material 8 so as to repair a via cutout 5 induced at the surface end of a via 1 due to the filling failure of via metal or the like and rolled with a buff or the like. The metal oxide powder is formed of SiO2 or Al2O3 excellent in wettability to a polyimide insulating layer 3. The metal oxide power 6 is forced into all the via cutouts 5 by rolling it with a buff or the like 5-6 times, then the metal oxide powder 6 attached to the surface is wiped off with a gauze or the like, and N2 gas or the like-is jetted to clean the surface of the base material 8. Metal of Al or the like is sputtered and etched into a corrective layer 2, the layer 2 is coated with polyimide, a via hole 1 is provided, and polyimide is subjected to a hard baking process, whereby a polyimide insulating layer 3 is formed. |
