A ceramic heater is provided that includes a power terminal for connecting a resistive heating element to a power source. An intermediate layer is disposed on an AlN ceramic substrate proximate the resistive heating element. The power terminal is bonded to the intermediate layer by an active brazing material. The intermediate layer is formed of Mo/AlN or W/AlN and has a coefficient of thermal expansion between that of the active brazing material and that of the AlN ceramic substrate so that thermal stress generated in the ceramic substrate can be reduced.