Abstract
Improvement has been made on the thermal conductivity of aluminum nitride ceramics which is one of the hopeful candidates of substrates for semiconductor devices. The thermal conductivity has been thought to be reduced by the presence of some impurities such as oxygen and transition metal ions in the ceramics. However, much improvement was made on the thermal conductivity of aluminum nitride ceramics by using a suitable amount of yttrium oxide and calcium oxide as a sintering aid. Addition of yttrium fluoride has also brought on faily good results for improvement of its thermal conductivity.
