Scaling Effects on Single-Event Transients in InGaAs FinFETs

The single-event-transient response of InGaAs FinFETs with different fin widths is examined using pulsed-laser and heavy-ion irradiation. Devices with wider fins collect more charge in both environments. Quantum-well structures confine charge collection in the channel, and determine the sensitive volume. Simulations show that the charge density produced by irradiation is similar for devices with different fin widths, but more charge is collected by wider fin devices due to the larger channel volume. Charge accumulated in the buffer and substrate layers modulates the body potential, altering the degree of back-gate control, leading to additional effects associated with charge accumulation in wider fin devices. Optical simulations for a model system suggest that optical phenomena in the fins should be considered for laser testing. These include optical interference, plasmonic enhancement at the metal-dielectric interfaces, and enhanced electron-hole pair recombination due to multiple reflections in multigate devices with nanoscale dimensions.