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:
Apr. 04, 2006
Filed:
Oct. 02, 2002
Toshiyuki Hamada, Kokubu, JP;
Masahiro Nakahara, Kokubu, JP;
Toshiyuki Hamada, Kokubu, JP;
Masahiro Nakahara, Kokubu, JP;
Kyocera Corporation, Kyoto, JP;
Abstract
There is provided a ceramic member for semiconductor manufacturing equipment which is formed of an alumina-based sinter containing an yttrium-aluminum-garnet at the amount of 3 to 50 wt %, silicon oxide at the amount of not more than 0.2 wt %, preferably 0.1 wt %, and the balance substantially alumina, wherein the sinter has dielectric loss of not more than 4×10particularly 2.5×10or less in the frequency range of 10 MHz to 5 GHz. Such a member may be formed of a ceramic sinter including an aluminum phase having mean crystal grain size in a range of 2 to 10 μm and a yttrium-aluminum-garnet phase having a mean crystal grain size in a range of 1.5 to 5 μm, wherein the ratio of the mean crystal grain size of the alumina phase to that of the yttrium-aluminum-garnet phase is larger than 1 and smaller than 7.