| 摘要 |
PURPOSE:To obtain the semiconductor element having excellent electric, thermal and mechanical characteristics by a method wherein the lead frame of the device is made to have structure coated with metal films of three layers. CONSTITUTION:The whole surfaces of outside leads 1, inside leads 2 and a die stage 3 are coated with a layer 4 of copper or silver. A middle metal layer 5 of nickel to act as the barrier layer preventing the alloying phenomenon is formed on the bonding regions of the inside leads 2 to adhere metal fine wires 7, and on the metal coated layer 4 of the die stage 3 at the equipping region of the element 7. Moreover the layer 6 of a metal (gold, for example) having the favorably adhesive property with the semiconductor element 7 and the metal fine wire 8 are formed thereon. The edge part of the metal layer 6 and the edge part of the nickel layer 5 are formed in a step type. After the semiconductor element 7 is adhered on the metal layer 6, they are sealed with resin 9 to complete the semiconductor device. |
