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:
Sep. 12, 1995
Filed:
May. 02, 1994
Seiji Nakahata, Hyogo, JP;
Takahiro Matsuura, Hyogo, JP;
Kouichi Sogabe, Hyogo, JP;
Akira Yamakawa, Hyogo, JP;
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
An aluminum nitride sintered body has a high breakdown voltage for serving as a substrate material particularly suited to highly integrated circuits. The aluminum nitride sintered body contains titanium, which is included as a solid solute in the aluminum nitride crystal lattice in a weight ratio of at least 50 ppm and not more than 1000 ppm. The unpaired electron concentration in the sintered body as determined from an absorption spectrum of electron spin resonance is at least 1.times.10.sup.13 /g. At least 0.1 percent by weight and not more than 5.0 percent by weight, in terms of TiO.sub.2, of an oxy-nitride of titanium and aluminum exists in the aluminum nitride sintered body. The aluminum nitride sintered body has a breakdown voltage of 20 kV/mm. The sintered body is obtained by nitriding aluminum nitride raw material powder in a nitrogen atmosphere at a temperature of 800 to 1400.degree. C., adding an oxy-nitride of titanium thereto with a sintering assistant, and sintering the mixture.