LEAD FRAME FOR SEMICONDUCTOR DEVICE

PURPOSE:To fabricate highly reliable chip bonds and wire bonds at a low cost, by forming a film of an Au-Sn alloy and a film of Ag on a die-pad part and an inner lead part in a lead frame, respectively. CONSTITUTION:An Au-Sn alloy film 8 is coated on a chip bonding part 2 of a lead frame 1 made of 42wt% Ni-Fe alloy. Ag films 9 are applied on wire bonding parts 3. The films are formed by a wet plating method or an evaporation method. By using this lead frame, an Si chip is bonded under the eutactic condition. Then the uniform wetting equivalent to the conventional method can be confirmed. Thus excellent ohmic conct property and mechanical bonding strength can be obtained.