| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain a porous silicon nitride ceramic having uniform and fine closed pores, and its manufacturing method. <P>SOLUTION: The porous silicon nitride ceramic having the uniform and fine closed pores is obtained by mixing a metallic silicon powder and a sintering aid, and heat treating it with 2 steps as a pretreatment, by a microwave heating, at a temperature of ≥1,000°C, wherein, the metallic silicon is nitriding reacted from its surface, and the metallic silicon is diffused into a nitride formed on an outer shell of the metallic silicon. This porous silicon nitride is having closed pores at a high rate, and excellent in mechanical performance. Therefore, it shows excellent performance, when used as a substrate for electronic circuit, etc., which is needed for hygroscopic resistance, low dielectric constant, and low dielectric loss, and also needed for mechanical strength. <P>COPYRIGHT: (C)2003,JPO |
