Silicon nitride substrate, silicon nitride circuit board utilizing the same, and use thereof
Patent 8029903 Issued on October 4, 2011. Estimated Expiration Date: July 27, 2026. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
Provided are a silicon nitride substrate and a silicon nitride circuit board with excellent electrical characteristics, and power control parts utilizing them.A silicon nitride substrate comprises a silicon nitride sintered body obtainable by sintering a silicon nitride powder in the presence of a sintering aid comprising MgO, Y2O3 and SiO2 in a proportion of (1) MgO/(MgO+SiO2)=34-59 mol %, and (2) Y2O3/(Y2O3+SiO2)=50-66 mol %, and a silicon nitride circuit board utilizes it.
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