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:
Apr. 13, 1993
Filed:
Feb. 20, 1992
Christopher J Lebeau, Tempe, AZ (US);
Shay-Ping T Wang, Tempe, AZ (US);
Motorola, Inc., Schaumberg, IL (US);
Abstract
A non-destructive method for testing quality of at least one bond which physically and electrically couples a package lead to an integrated circuit. A thermal gradient is created across the at least one bond which causes heat transfer thru the at least one bond. Heat transfer is measured which is proportional to area at a bond interface. The measured heat transfer thru the at least one bond is compared with heat transfer data taken under substantially equal conditions of known good bonds thereby determining quality of the at least one bond. The heat transfer is indirectly measured by creating a mechanical vibration at an input area and by measuring the time it takes the mechanical vibration to reach an output area after the mechanical vibration has traveled through the at least one bond.