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:
Jul. 19, 1994
Filed:
Jul. 12, 1993
Noboru Hashimoto, Suita, JP;
Kyoji Tanaka, Kobe, JP;
Susumu Kajita, Hirakata, JP;
Hiroyoshi Yoden, Kadoma, JP;
Matsushita Electric Works, Ltd., Osaka, JP;
Abstract
An aluminum nitride (AlN) sintered product with a high thermal conductivity of 120 W/m.multidot.k or above can be produced at a relatively low sintering temperature of 1650.degree. C. or below in accordance with the following process of the present invention. That is, an A1N powder having a specific surface in a region of about 3.5 to 8 m.sup.2 /g and an oxygen content between 0.5 to 1.8 wt % is mixed with optimum additive amounts of sintering aids (I) to (III) to obtain a mixture powder. The sintering aid (I) is at least one selected from the group consisting of rare earth oxides and rare earth compounds which are converted to corresponding rare earth oxides by the sintering. The sintering aid (II) is at least one selected from the group consisting of alkaline earth oxides and alkaline earth compounds which are converted to corresponding alkaline earth oxides by the sintering. The sintering aid (III) is at least one selected from the group consisting of LAB.sub.6, NbC, and WB. The optimum additive amount of LaB.sub.6 is in a range of 0.05 to 3 wt % of the A1N sintered product. The mixture powder is compacted, and then sintered at the sintering temperature in a non-oxidation atmosphere to obtain the A1N sintered product.