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:
Dec. 24, 1991
Filed:
Sep. 21, 1990
Ronald A Norell, Carlsbad, CA (US);
Unisys, Blue Bell, PA (US);
Abstract
A multichip integrated circuit module includes a ceramic substrate, a plurality of integrated circuit chips mounted on the substrate, and a metal lid which covers the chips and rests on the substrate without attaching to it. Also, the module includes two thin cylindrical members. One cylindrical member surrounds the substrate and makes an airtight solder joint to the substrate's perimeter, while the other cylindrical member surrounds the lid and makes an airtight solder joint to the lid's perimeter. Both cylindrical members run parallel to each other and make an airtight welded joint with each other. When the lid and substrate thermally expand at unequal rates, one thin cylindrical member is deflected by the other member. When a defective chip is replaced, the joint between the two cylindrical members is ground away; and subsequently, the remaining parallel portions of the cylindrical members are rewelded together.