We measured the effects of 3-MeV proton irradiation on
AlInN/AlIn/GaN HEMTs. After fluences larger or equal to
1013 p/cm2, the devices experience threshold voltage shifts and
transconductance degradation, visible both in DC and pulsed
measurements, within the range of the observed degradation in
conventional GaN HEMTs. Some differences in the post-rad
response are visible between the two types of tested devices,
likely due to a different initial concentration of defects.
Source field plates are shown to have a very limited impact on
the radiation response