| 摘要 |
The invention provides an AlN substrate that has excellent heat transfer efficiency between the AlN substrate and another member, such as a semiconductor substrate, to be bonded to a bonding surface of the AlN substrate, and provides a method for producing the AlN substrate. The AlN substrate is composed of an AlN sintered body containing a group 2A element and a group 3A element, and the surface roughness Ra of the bonding surface is 3 nm or less, and, in voids having long diameters of 0.25 µm or more that are exposed on the bonding surface, the mean value of the long diameters is 1.5 µm or less, and the maximum value thereof is 1.8 µm or less. The method for producing the AlN substrate includes sintering, at a temperature of 1,500 to 1, 900°C, a precursor formed of a sintering material that contains 88.7 to 98.5 mass% with respect to AlN, 0.01 to 0.3 mass% with respect to a group 2A element in oxide equivalent, and 0.05 to 5 mass% with respect to a group 3A element in oxide equivalent so as to form a sintered body and applying HIP treatment onto the sintered body at a temperature of 1,450 to 2,000°C and at a pressure of 9.8 MPa or more. |
