Simulation of Improved 3D tri-gate 4H-SiC MESFETs with Recessed Drift Region

摘要

An improved 3D tri-gate 4H-SiC MESFETs structure with recessed drift region was proposed and its DC and RF electrical performances were studied by numerical simulation. The recessed source/drain drift region of the proposed structure is to eliminate gate depletion layer extension to source/drain to decrease gate-source capacitance as well as to reduce the channel thickness between gate and drain to increase breakdown voltage. The simulated results showed that the maximum theoretical output power density,the cut-off frequency (fT) and the maximum oscillation frequency (fmax) of the proposed structure are 18.5W/mm,19.3GHz and 74.1GHz compared to 15.5 W/mm, 16.1GHz and 55.9GHz of that of the published 3D tri-gate structure,respectively.