Gate-Length Dependence of DC Characteristics in Submicron-Gate AlGaN/GaN High Electron Mobility Transistors

Abstract

We investigated the gate-length dependence of room-temperature DC operation in submicron-gate AlGaN/GaN high-electron-mobility transistors (HEMTs). The threshold voltage was reduced by the short-channel effect, which is only dependent on the aspect ratio of the gate length to the barrier-layer thickness. On the other hand, the transconductance was restricted by the source resistance, and was dependent on not only the gate length LG but also the source–gate length LSG. The transconductance was increased by reducing LSG rather than LG in the submicron-gate HEMTs.