Effects of adding Y(2)O(3) on the electrical resistivity of aluminum nitride ceramics

Electrical resistivity of AlN ceramics was examined with various amounts of Y(2)O(3) within 0 to 4.8 mass%. The electrical resistivity at room temperature varied from 10(16) to 10(10) [Omega].cm with different Y(2)O(3) amounts and at sintering temperatures. In the typical samples sintered at 1900'C, a smaller amount of Y(2)O(3) addition with 0.1 to 0.5 mass% gives the lowest electrical resistivity of 10(10) [Omega].cm, whereas the higher amount of Y(2)O(3) maintains high resistivity of more than 10(13) [Omega].cm. The results derived from different analytical techniques such as impedance analysis, cathodoluminescence spectrum and microstructural analysis explain the importance of the oxygen concentration in the AlN grain for the electrical resistivity of AlN ceramics.