| US 7,612,006 B2 | ||
| Conductive silicon nitride materials and method for producing the same | ||
| Katsutoshi Komeya, Kanagawa (Japan); Junichi Tatami, Kanagawa (Japan); Takeshi Meguro, Kanagawa (Japan); Tomofumi Katashima, Kanagawa (Japan); and Toru Wakihara, Kanagawa (Japan) | ||
| Assigned to Yokohama TLO Company, Ltd., Kanegawa (Japan) | ||
| Appl. No. 11/664,072 PCT Filed Sep. 27, 2005, PCT No. PCT/JP2005/017701 § 371(c)(1), (2), (4) Date Mar. 27, 2007, PCT Pub. No. WO2006/038489, PCT Pub. Date Apr. 13, 2006. |
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| Claims priority of application No. 2004-290328 (JP), filed on Oct. 01, 2004; and application No. 2004-376116 (JP), filed on Dec. 27, 2004. | ||
| Prior Publication US 2008/0076657 A1, Mar. 27, 2008 | ||
| Int. Cl. C04B 35/584 (2006.01); C04B 35/78 (2006.01) | ||
| U.S. Cl. 501—97.2 [501/97.3; 501/97.4; 501/99; 501/100; 252/506; 252/507; 252/520.22; 252/521.3] | 13 Claims |
| 1. A sintered silicon nitride with a conductivity of higher than 10−1Ω−1 m−1 produced by (a) preparing a mixture, comprising 0.5 to 10 weight percent of rare-earth compounds in terms of oxide, 0.1 to 5 weight percent of aluminum oxide or its precursor, 0 to 5 weight percent of aluminum nitride, 0.1 to 5 weight percent of oxides of titanium group or other titanium group compounds in terms of equimolar titanium nitride wherein the titanium group compounds can be converted to nitrides of titanium group elements by sintering, and silicon nitride powder as a balance, and further comprising 0.3 to 12 weight percent of carbon nanotubes (CNT) relative to 100 weight percent of the foregoing mixture, wherein the silicon nitride powder has an average grain diameter of less than 1.0 μm and contains less than 1.7 weight percent of oxygen content and more than 90 weight percent of alpha phase type silicon nitride, and (b) sintering the mixture by a normal pressure sintering method or an ambient pressure sintering method. |