Lead frame for IC having a wire bonding part composed of multi-layer structure of iron containing alloy, refractory metal and aluminum
AssigneeSumitomo Metal Mining Co., Ltd.
InventorHideyasu Nikaido
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Abstract
In a lead frame for an IC which is provided on a wire bonding part of the inner lead unit thereof with an aluminum coating, possible detrimental diffusion of the component elements of the lead frame into the aluminum coating can be effectively precluded by having a layer of a high melting point metal interposed between the lead substrate and the aluminum coating in the wire bonding part without appreciably increasing the cost of production.
Claims5
A lead frame for a semiconductor integrated circuit device which includes an inner lead unit that has a wire bonding part and is composed of an iron-containing alloy, a layer of a metal having a melting point of at least 1700.degree. C. on said wire bonding part of said inner lead unit, and a coating of aluminum on said layer of metal;
- said layer of metal reducing diffusion of metals from said inner lead frame to said coating of aluminum when subjected to elevated temperatures of at least 500.degree. C.
Dependencies are inferred from the claim text.