Asymmetric 3D tri-gate 4H-SiC MESFETs with a recessed drain drift region

An improved asymmetric 3D tri-gate 4H-SiC metal–semiconductor field effect transistor with a recessed drain drift region was proposed in order to improve the power and frequency performance of the device. The dc and RF electrical characteristics of the proposed structure were studied in detail by numerical simulation. The simulated results showed that the maximum theoretical output power density of the proposed structure is about 36% larger than that of the published symmetric 3D tri-gate structure due to significant improvement of saturation drain current and breakdown voltage. The cut-off frequency (fT) and the maximum oscillation frequency (fmax) of the proposed structure are 20.6 GHz and 82.4 GHz compared to 16.1 GHz and 55.9 GHz of those of the published 3D tri-gate structure, respectively