Single-Event Mechanisms in InAlSb/InAs/AlGaSb High Electron Mobility Transistors
Single-event mechanisms in InAlSb/InAs/AlGaSb high electron mobility transistors (HEMTs) are identified and investigated. Single-event transients are characterized using broadbeam and microbeam experiments along with 2-D technology computer-aided design (TCAD) modeling. The experiments show that single-event transients can be generated not only in the channel region but also across the drain-source alloy and buffer interface. The prevalence of strong single-event transient sensitivity to gate bias is demonstrated through broadbeam experiments, where the integrated charge peaks at threshold bias and drops off at both depletion and accumulation biases. A type-II band alignment in the InAlSb/InAs/AlGaSb HEMT modulating charge transport and electric field in the channel is shown to be responsible for the observed single-event transient sensitivity to gate bias. The effects of processing-induced device threshold voltage variations on the corresponding single-event response are studied through 2-D TCAD modeling.