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:
Jan. 16, 1990
Filed:
Dec. 05, 1988
Wilbur T Layton, San Diego, CA (US);
Dale L Robinson, Escondido, CA (US);
Jerry I Tustaniwskyj, Mission Viejo, CA (US);
Unisys Corporation, Blue Bell, PA (US);
Abstract
A leak in an enclosure of an integrated circuit package is detected by the steps of: filling the enclosure with a first gas at the time the enclosure is sealed; subsequently enveloping the integrated circuit package with a second gas that is different than the first gas; holding the second gas at a constant pressure over a certain time period; and sensing a surface of the enclosure, during the above steps, for the presence of microscopic deflections. If the enclosure has a gross leak, no deflection will occur when the package is initially enveloped with the second gas. If the package has a minor leak, a deflection will occur when the package is initially enveloped with the second gas, and the amount of the deflection will decrease during the holding time period. Preferably, the second gas is lighter than the first gas so that it diffuses into the cavity faster than the first gas diffuses out of the cavity; and preferably the microscopic deflections of the enclosure are sensed with a mechanical probe in increments of 0.0001 inches.