Enhanced high-temperature volume resistivity of AlN by doping

Abstract The addition of various oxide dopants for AlN were investigated aiming to increase the AlN volume resistivity at high temperature. It was confirmed that the volume resistivity of 1 mol% MgO doped AlN shows four orders of magnitude higher than that of non-doped AlN. To further clarify the effect of MgO doping, we sintered various kinds of AlN with different MgO concentration and grain sizes, and the microstructures were investigated by transmission electron microscopy. The results suggest the inversion domain boundary appeared in the MgO doped AlN might be the possible reason for the increase of volume resistivity.