Making insulating Al2O3 electrically conductive without loss of translucency using a small amount of ITO grain boundary phase

Abstract The electrical conductivity of Al2O3 must be improved from 10−16 S/cm to the range between 10−5 and 100 S/cm, when insulating Al2O3 parts are employed for semiconductor manufacturing equipment. To remain the advantages of Al2O3 ceramics, it is necessary to control electrical conductivity using a small amount of conducting phase by sintering in air atmosphere. In this study, electrical conductivity of Al2O3 ceramics was successfully increased from 10−16 to 10−1 S/cm by precipitating a small amount of indium tin oxide (ITO) grain boundary phase, without evident deterioration of translucent of sintered Al2O3 polycrystals.