| 摘要 |
PURPOSE:To facilitate the deburring of the molded resin in the lead frame for the integrated circuit, by selectively performing the treatment of the surface of the material in the region on which a gold or silver film is formed, and improving the close contacting property of the film. CONSTITUTION:The surface of the lead frame of an iron-nickel alloy is selectively masked with a masking jig such as silicon rubber and the like. A partial aventurine surface 8' having the diameter of concave and convex parts of about 20mum and the roughness of 0.1-0.2mum is obtained by the etching for 30-90sec by using acid comprising sulfuric acid, fluoride, and hydrogen peroxide. Then, a silver film 9, which is about 20mum thick and has strong contacting property, is formed by silver- plating the partial aventurine surface 8'. Thereafter, a semiconductor element is placed on the film part, bonding is performed, and the molding is made by resin. The silver film 9 has excellent contacting property because of the partial aventurine surface 8'. Since aventurine treatment is not applied on an outer lead part 7, the deburring work is easy. |
