Thermal management: Use of aluminum-nitride multilayer heaters in dispenser cathodes

Dispenser cathodes must operate at specific temperature while applying specific heater power. To achieve the required temperature a wire coil heater is commonly used. During the heater and cathode design process several aspects (structure rigidness, heat transfer path, uniformity of surface temperature distribution, heater and cathode life) have to be taken under consideration which makes the design difficult and costly. This paper offers an insight into study of aluminum-nitride drop-in heater package as a heating element for dispenser cathodes.