Advances in DC/RF Performance of AlGaN/GaN MIS-HEMT by Incorporating Dual Metal Gate Architecture

This study presents a modified version of MIS-HEMT via incorporation of dielectric pocket with a dual metal enabled gate (DP-DMG) architecture to achieve an enhancement in the electrical performance of AlGaN/GaN HEMT. A noteworthy improvement in DC/RF characteristics is observed with DP-DMG HEMT in comparison to conventionally used single metal gated Schottky (SMG) HEMT including gate leakage. Moreover, DP-DMG is further studied with different dielectrics to tune its electrical performance along with the depth of the dielectric pocket. The maximum rise in drain current and transconductance achieved with different dielectric DP-DMG HEMT is 13% and 13.5%, respectively. Apart from this, a significant positive shift of similar to 0.6 V is recorded with HfO2 with a dielectric thickness of 5 nm. RF simulations showed significant improvement (similar to 2x) in the cut-off frequency of DP-DMG HEMT in comparison to SMG HEMT.