New structures named as recessed gate and channel (RGC) silicon carbide (SiC) based metal semiconductor field effect transistors (MESFETs) are reported in this paper, in which the gate is recessed into the channel, and the channel is recessed into the p-buffer layer at the source and/or the drain side. Important parameters such as short channel effect, maximum DC trans-conductance (gm), drain current, breakdown voltage and output resistance of the proposed structures are simulated and compared with the conventional 4H–SiC MESFET. Simulation results disclose that, compared to the conventional structure, the structure with recessed full gate and channel (FGC): 1. Improves the DC trans-conductance (gm). 2. Increases the output resistance. 3. Enhances the breakdown voltage. 4. Reduces the short channel effect. Moreover, source side recessed gate and drain side recessed channel (SG–DC) structure has higher gm and output resistance in comparison with the conventional structure. Drain side recessed gate and source side recessed channel (DG–SC) structure has larger breakdown voltage and drain current than those of the conventional structure.

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