Radiation Effects And Damage Mechanisms Of Domestic GaAs MESFET

GaAs metal semiconductor field effect transistor(GaAs MESFET)are widely used in satellite,radar,electronic countermeasure and other fields.It is unique in microwave devices and integrated circuits.With the development of microwave technology in China,it is an urgent problem to study the reliability of new domestic GaAs MESFETs in space environment.In this paper,the radiation effect and damage mechanism of the new type GaAs MESFET under the action of low energy electrons,high-energy electrons,low-energy protons and high-energy protons are studied.The results of 150 keV low energy electron irradiation show that with the increase of irradiation fluence,the source drain saturation current of GaAs MESFET increases slightly,the series resistance decreases slightly,the maximum transconductance increases slightly,and the transfer characteristics,sub threshold characteristics and gate source schottky forward characteristics remain unchanged.DLTS test results show that there are no new defects in the device after 150 keV electron irradiation,but the concentration of the original defects decreases slightly,which is attributed to the injection annealing effect of 150 keV electron on the GaAs MESFET;after 1 Me V high energy electron irradiation,with the increase of irradiation fluence,the source drain saturation current of GaAs MESFET decreases continuously,the series resistance increases continuously,the pinch off voltage shows a large positive drift,the subthreshold slope decreases,the subthreshold swing increases,the gate control ability decreases,the maximum transconductance decreases,and the gate source schottky forward characteristics remain basically unchanged.DLTS test results show that after 1 Me V electron irradiation,the original defects in the device disappear and new defects appear,which are H(260),E(310)and E(375),respectively,and the three kinds of defects are displacement defects.The results of 150 keV low energy proton irradiation show that with the increase of irradiation fluence,the source drain saturation current of GaAs MESFET decreases significantly,the series resistance increases significantly,the maximum transconductance decreases significantly,the pinch off voltage has a small positive drift,the subthreshold slope decreases,the subthreshold swing increases,the gate control ability decreases,and the gate source schottky forward characteristics degrade,the ideal factor increases.DLTS test results show that after 150 keV proton irradiation,the intrinsic defects disappear and new defects appear,which are H(140)and H(260),respectively;after 10 Me V proton irradiation,with the increase of irradiation fluence,the source drain saturation current of GaAs MESFET decreases,the series resistance increases slightly,the transfer characteristics,sub threshold characteristics and gate source schottky forward characteristics remain unchanged,and the maximum transconductance decreases slightly.DLTS test results show that 10 Me V proton irradiation does not produce new defects inside the device,but the concentration of original defects increases slightly,which indicates that 10 Me V proton irradiation only aggravates the original defects of GaAs MESFET.SRIM simulation results show that 150 keV low energy protons have greater influence on the gate schottky junction,while 10 Me V high energy protons have less influence.