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. 16, 1993
Filed:
Aug. 05, 1991
Kevin D Moore, Schaumburg, IL (US);
John W Stafford, St. Charles, IL (US);
William M Beckenbaugh, Barrington, IL (US);
Ken Cholewczynski, Streamwood, IL (US);
Motorola Inc., Schaumburg, IL (US);
Abstract
A method for forming a solder-bumped terminal on a planar dielectric substrate utilizes a terminal of a particular configuration and comprises depositing onto the terminal a thin plate of solder alloy and reflowing the solder alloy to form a bump. The terminal configuration includes an enlarged terminal pad connected to a relatively narrow linear runner section. Preferably, the runner section width is between about 50 and 150 microns, whereas the pad width is between about 1.2 and 2.0 times the runner section width. The terminal is initially fabricated to include a metal layer adjacent the substrate formed, for example, of copper and a thin, outer plate composed of the solder alloy. The solder plate is deposited in a uniform thickness to both the terminal pad and the adjacent runner section. The terminal is then heated to melt the solder plate, whereupon the molten solder is drawn from the runner onto the enlarged pad to form a bump. In a preferred embodiment, a solder plate between about 10 and 25 microns is electrodeposited onto the terminal and reflowed to form a bump having a height between 60 and 80 microns.