| 摘要 |
PURPOSE:To reduce cost by directly forming a silver plating layer on a metallic substrate constituting a lead frame through an electroless plating method. CONSTITUTION:A metallic substrate 1 shaping a lead frame is pre-treated, and dipped in an etching liquid, and the outer surface of the substrate is etched and treated. The substrate is washed by ion-exchange water, dried, and introduced into a vacuum furnace and heated, and nitrogen gas is encapsulated into the vacuum furnace to return pressure in the furnace to atmospheric pressure, thus cooling the frame. The substrate is forwarded to a rinsing treating process 6, dipped in a rinsing liquid, washed by ion-exchange water, and dried. On the other hand, a silver plating liquid is compounded in a silver plating liquid compounding process 7, and the lead frame is plated with silver 2 as fast as possible. Accordingly, a plating treating process is simplified, and the cost of the lead frame is reduced. |
