| abstract |
An aluminum nitride sintered body having a thermal conductivity of at least 100 W/mK, preferably at least 120 W/mK, more preferably at least 140 W/mK, and most preferably at least 160 W/mK is produced by baking with a sintering additive using an aluminum nitride starting powder of high purity derived by direct nitriding of metallic aluminum. The sintering additive is selected from compounds of Group IIa, IIIa, and IIIb metals of the periodic table and preferably it comprises predominantly Y2O3 or a precursor thereof. In one embodiment, the starting powder and the sintering additive are slurried with a binder and an organic solvent and shaped into a sheet. The sheet, after drying and binder removal, is suitable for use in making multilayered ceramic substrates, ceramic heaters, radiators, and the like. |