SILICON NITRIDE SINTER HAVING HIGH THERMAL CONDUCTIVITY AND PROCESS FOR PREPARING THE SAME

摘要

A silicon nitride sinter having high thermal conductivity and comprising a crystal grain phase of silicon nitride and a grain boundary phase containing 1 to 20 % by weight in terms of oxide of at least one compound of an element selected from among yttrium and lanthanides, wherein 0.01 to 10 % by weight based on the sinter of free silicon is dispersed. The silicon sinter possesses high strength and high thermal conductivity and hence is useful as components for various structures, such as heat dissipation/insulation boards for semiconductor devices, mechanical devices, and office automation equipment.