The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 26, 2002
Filed:
Dec. 03, 1999
George S. Bokisa, North Olmsted, OH (US);
Craig V. Bishop, Lakewood, OH (US);
John R. Kochilla, Cleveland, OH (US);
Atotech Deutschland GmbH, Berlin, DE;
Abstract
A process of preserving solderability and inhibiting tin whisker growth of exposed copper or copper alloy surfaces on a substrate comprises the steps of preparing an immersion tin plating solution substantially free of other immersion-platable metals; applying the immersion tin plating solution to the substrate to form a tin coating on the surfaces; preparing an immersion alloy plating solution containing at least two immersion-platable metals; applying the immersion alloy plating solution to the substrate by immersing the substrate in the immersion alloy plating solution to form an alloy cap layer on the tin coating. The immersion platable metals in the immersion alloy plating solution may be at least two metals selected from tin, silver, bismuth, copper, nickel, lead, zinc, indium, palladium, platinum, gold, cadmium, ruthenium and cobalt. The immersion platable metals may be added to the solution in the form of metal salts