Electrolysis: processes – compositions used therein – and methods – Electrolytic coating – Forming multiple superposed electrolytic coatings
Patent
1997-03-31
1998-03-17
Gorgos, Kathryn L.
Electrolysis: processes, compositions used therein, and methods
Electrolytic coating
Forming multiple superposed electrolytic coatings
205122, 205176, C25D 510, H01L 23495
Patent
active
057282854
ABSTRACT:
A lead frame for a semiconductor device includes a base which is coated by a protective coating. The lead frame base is made of a ferrous material. The protective coating is made by sequentially electroplating a copper-containing layer, a silver-containing layer and a palladium-containing layer. Protective coatings constructed in this way are bondable, solderable, oxidation resistant, corrosion resistant, free of lead (Pb), resistant to high temperatures, cost effective, and cosmetically acceptable. It is also possible to use a layer of tin or a tin alloy in place of the silver layer.
REFERENCES:
patent: 3648355 (1972-03-01), Shida et al.
patent: 4141029 (1979-02-01), Dromsky
patent: 4404080 (1983-09-01), Jahani
patent: 4405432 (1983-09-01), Kosowsky
patent: 4441118 (1984-04-01), Fister et al.
patent: 4486511 (1984-12-01), Chen et al.
patent: 4529667 (1985-07-01), Shiga et al.
patent: 4628165 (1986-12-01), Nobel et al.
patent: 4888449 (1989-12-01), Crane et al.
patent: 4894752 (1990-01-01), Murata et al.
patent: 5001546 (1991-03-01), Butt
patent: 5138431 (1992-08-01), Huang et al.
patent: 5221859 (1993-06-01), Kobayashi et al.
patent: 5360991 (1994-11-01), Abys et al.
patent: 5454929 (1995-10-01), Kinghorn
patent: 5486721 (1996-01-01), Herklotz et al.
Donald C. Abbott et al., Palladium as a Lead Finish for Surface Mount Integrated Circuit Packages; Texas Instruments Incorporated, Dallas, Texas, frm IEPC Proceedings, Sep. 1990, pp. 110-119.
Gorgos Kathryn L.
Leader William T.
National Semiconductor Corporation
LandOfFree
Protective coating combination for lead frames does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Protective coating combination for lead frames, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Protective coating combination for lead frames will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-954732