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. 08, 1994
Filed:
Jun. 19, 1992
Akira Yamakawa, Hyogo, JP;
Akira Sasame, Hyogo, JP;
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
An aluminum nitride sintered body that has been fired/formed to have a prescribed sintered configuration, is used as a substrate. A metal paste of tungsten is prepared and applied to the substrate. The metal paste of tungsten contains oxide components of at least 1 percent by weight of the paste and not more than 40 percent by weight of the paste. The oxide components include SiO.sub.2 of at least 1 percent by weight of the oxide components and not more than 40 percent by weight of the oxide components. The oxide components include CaO and Al.sub.2 O.sub.3 in a weight ratio of at least 0.5 and not more than 2 of CaO to Al.sub.2 O.sub.3. The aluminum nitride sintered body coated with the metal paste is heated/fired in a non-oxidizing atmosphere at a temperature of at least 1400.degree. C. and not more than 2000.degree. C.