GaN multichannel devices with latch-induced sub-60 mV/decade subthreshold slope.

Abstract

AlGaN/GaN-based Superlattice Castellated Field Effect Transistors (SLCFET) are the foundation for high power RF amplifiers and switches for future radars, although their reliability is not yet well understood. Transistor latching is observed in GaN transistors for the first time. At the latching condition, drain current (ID) transits from an OFF-State value to high ON-State value sharply with a slope less than 60 mV/decade. Current-voltage (I-V), simulations and correlated electroluminescent (EL) emission at the latching condition indicates that triggering of fin width dependent localized impact ionization is responsible for latching. This localization is attributed to the presence of fin width variation arising due to variability in the fabrication process. The reversible and non-degrading nature of the latching condition is promising for next generation RF applications.