Total Dose Hardness of Microwave GaAs Field Effect Transistors

GaAs MESFET devices are becoming increasingly desirable for satellite communication systems and other microwave applications because of their performance and high reliability. Low power, low noise MESFETs are used in satellites such as INTELSAT V. Medium to high-power GaAs MESFET amplifiers have been developed for the next generation satellites. A variety of radiation tests have been run, primarily on GaAs optoelectronic devices such as LED over the past 15 years. Neutron displacement damage and transient dose rate effects have dominated the research while total dose testing has been minimal. In this paper, the total dose test results of five types of GaAs MESFET devices are presented. These MESFETs range from high-power (2.5 watt) to very low-power, low-noise (0.01 watt, 0.5 ¿m gate length) devices, from four manufacturers. A total of 22 amplifiers/devices were exposed to cobalt -60 ¿ radiation source under biased and unbiased conditions. All devices were irradiated up to 2 × 108 rad (GaAs). The damage was minimal and all devices were functionally operable after irradiation.