SEU measurements on HFETs and HFET SRAMs

The single-event-upset (SEU) response of n⁺-AlGaAs/GaAs heterostructure field-effect transistors (HFETs) and HFET static random access memories (SRAMs) was evaluated by measuring their response to focused-electron-beam pulses. Initially the pulses were used to measure and model HFET drain and gate SEU responses. Circuit simulations using these SEU models predicted that an HFT memory is most vulnerable to a single-particle event in the area between the drain and the source (drain hit) of the OFF pull-down HFET. Subsequent testing of an HFET SRAM cell confirmed the above prediction. These SEU evaluations of HFETs and HFET memories show that measurements on individual HFETs and circuit simulations of SEU hits can be used to predict the SEU response of HFET memories