Dual-metal gate AlGaN/GaN high electron mobility transistors: A theoretical study

The effect of dual-metal gate (DMG) on AlGaN/GaN high electron mobility transistors (HEMTs) has been investigated. An additional peak in the electric field is present in the interface between two metals in DMG device and leads to an enhancement in average drift velocity under the gate. Improvement in both output current and transconductance is observed in the device with DMG compared to its single-metal gate counterpart. Moreover, drain induced barrier lowering effect is suppressed as the device scales down to sub-micrometer due to the presence of screening effect in the channel potential in the DMG HEMTs.