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:
Feb. 23, 1999
Filed:
Jun. 23, 1997
Kyocera Corporation, Kyoto, JP;
Abstract
A sintered aluminum nitride contains rare earth elements (RE) in amounts of from 3 to 10% by weight in terms of RE.sub.2 O.sub.3, alkaline earth elements (R) in amounts of from 0.3 to 3.0% by weight in terms of RO, and silicon atoms in an amount of from 0.3 to 1.0% by weight in terms of SiO.sub.2, the grain boundaries of AlN crystals being chiefly a YAG type crystalline phase. The sintered product is obtained by firing at a temperature as low as 1700.degree. C. or lower, has a thermal conductivity of not smaller than 60 W/m.cndot.K, loses weight in an amount of not more than 10 mg/cm.sup.2 when it is left to stand in a 4N NaOH aqueous solution maintained at 70.degree. C. for one hour, and exhibits excellent resistance against the alkalis.