Radiation tolerant GaAs MESFET with a highly-doped thin active layer grown by OMVPE

A novel GaAs MESFET structure with high radiation tolerance is proposed. Changes in electrical parameters of a GaAs MESFET as a function of total gamma -ray dose were found to be caused mainly by a decrease in the effective carrier concentration in an active layer. The structure was designed from a simulation based on an empirical relationship between the changes of the effective carrier concentration and the total gamma -ray dose. It was successfully demonstrated by utilizing a highly doped thin active layer (4*10/sup 18/ cm/sup -3/, 100 AA) grown by organometallic vapor-phase epitaxy (OMVPE). This MESFET can withstand a dose ten times higher (1*10/sup 9/ rads(GaAs)) than a conventional one can.<
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