| 摘要 |
PURPOSE:To enable simultaneous vapor deposition on the side and the back of leads by a method wherein one surface of a lead frame is sprayed with an Al vapor ionized with the plasma of an inert gas at 10<-2>-10<-5>Torr. CONSTITUTION:In an Ar gas plasma at 10<-2>-10<-5>Torr, Al ionizing vapor deposition is applied to one surface of the lead frame of know composition by using pure Al or Al-Si alloy as the evaporation source. In the case of the thickness of the lead frame e.g. at 0.25mm., if the lead width is 2mm. or less, the coating rate of the back is 100%; if the width is 1mm. or less, the film thickness and quality are both uniform. With this construction, the process is simplified by both-coating by vacuum vapor deposition, and the torsion of base filaments does not generate. Besides, the title frame is excellent in adhesion and minuteness and has good line junction property. |
