抄録
In the electronics processes, downsizing of various electronic parts and increase in load of semiconductor elements cause the increase in heat production. Therefore AlN with high thermal conductivity, radiativity, and expansibility similar to Si is utilized as semiconductor packaging materials. For this purpose, highly pured AlN is required. Excellent properties of AlN remarkably fall down with increase in concentration of impurities. In recent years, AlN is manufactured by the direct nitriding and the carbothermal reduction methods. However, these methods have the problems of high reaction temperature (1500°C) and also the difficulties in continuous operations.In the present study, we synthesized AlN fine powder by direct nitriding method in a fluidized bed. The present process is expected to enable the continuous production of AlN fine powder with high conversion rate at relatively low temperature, because fluidized bed method gives excellent heat exchange; Al material are melted and distributed in the bed. To find suitable operation conditions for efficient continuous synthesis of AlN in a fluidized bed with bed materials of AlN,various operational conditions were tested. it was demonstrated that products with high purity AlN without unreacted Al were obtained at relatively low temperature (1200°C). However some parts of the product was obtained not as fine powder but as agglomerates.
