ULTRA-PURE SPHERE-LIKE BETA SILICON NITRIDE POWDER WITH LOW RADIOACTIVITY, PREPARATION METHOD THEREFOR AND USE THEREOF

摘要

Disclosed is an ultra-pure sphere-like β silicon nitride powder with a low radioactivity, wherein the degree of sphericity is between 0.5-0.99, the uranium impurity content is < 5 ppb, the thorium impurity content is < 5 ppb, and the particle size ranges between 0.5 µm-50 µm. As a filler of an electronic encapsulation material, β silicon nitride powder is suitable for a memory semiconductor encapsulation material with a high thermal conductivity.