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. 04, 1994
Filed:
Nov. 12, 1991
Henry F Breit, Attleboro, MA (US);
James A Forster, Barrington, RI (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A layer of ceramic material such as alumina is plasma-deposited on a sheet member such as molybdenum or a composite laminate of molybdenum and graphite or other material of low thermal expansion to form a circuit unit substrate having a thick, adherent, electrically-insulating coating on a light, rigid and thermally-conducting base. Thick and thin film materials are deposited and fired on the insulating coating to provide conductors, insulators or resistors or the like in a circuit unit. The materials of the sheet member and of the insulating coating are selected to have matching thermal expansion coefficients so that the substrate remains flat and free of bowing during the firing of the thick and thin film materials. The plasma-deposited electrically-insulating layer is sealed to prevent moisture absorption during use.