METHOD FOR CALCINING ALUMINUM NITRIDE SUBSTRATE

摘要

PURPOSE:To eliminate the unbalance of a calcination atmosphere and to prevent the generation of warpage by forming recesses on a boron nitride substrate surface disposed with an aluminum nitride substrate, putting aluminum nitride powder into the recesses and calcining the powder. CONSTITUTION:The aluminum nitride substrate 14 is disposed on a boron nitride plate 21 housed into a calcination vessel 11 and the aluminum nitride powder 15 is packed to the inner side of the vessel 11. The many small recesses 21a are formed atop the boron nitride substrate 21 and the aluminum nitride powder 22 is put into the recesses 21a in the state of having no contact with the substrate 14 and is then calcined. The aluminum nitride powder 15 is heated and the gaseous nitrogen contg. aluminum enters the inside of the holes of the spacer 13 disposed with the substrate 14. The gaseous nitrogen contg. the aluminum is simultaneously generated from the above-mentioned recesses 21a. The unbalance is eliminated in the atmosphere around the substrate 14 in this way and the generation of the warpage in the calcined substrate 14 is decreased.