Coating of Si₃N₄ Fine Particles with AlN by Fluidized Bed-CVD

Abstract

Agglomerates of 100250 μm consisting of Si₃N₄ primary particles of 0.76 μm were made with a rotary vibrating sieve. Si₃N₄ fine particles were coated with AlN by gas phase reaction with AlCl₃ and NH₃ in some fluidized beds of the agglomerates. The cross sectional distribution of AlN in the agglomerate was measured by EPMA analysis. As a result, uniform deposition of AlN was obtained at a relatively low reaction temperature and low gas velocity.