| abstract |
An aluminum nitride substrate having a via hole (3) and an inner conductive layer (2), wherein an aluminum nitride sintered body has a high thermal conductivity, has a high bonding strength to the layer (2) and the via hole (3), and are excellent in other properties. The substrate comprises a conductor layer (2) formed thereinside, and an aluminum nitride sintered body formed with at least one conductive via hole (3) between the inner conductive layer (2) and one surface of the substrate, characterized in that the aluminum nitride sintered body has a thermal conductivity at 25°C of at least 190 W/mK and a bonding strength to the inner conductive layer (2) of at least 5.0 kg/mm2. |