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A Novel 4H-SiC MESFET with a Heavily Doped Region, a Lightly Doped Region and an Insulated Region.

ABSTRACT: A novel 4H-SiC MESFET was presented, and its direct current (DC), alternating current (AC) characteristics and power added efficiency (PAE) were studied. The novel structure improves the saturation current (I_dsat) and transconductance (g_m) by adding a heavily doped region, reduces the gate-source capacitance (C_gs) by adding a lightly doped region and improves the breakdown voltage (V_b) by embedding an insulated region (Si₃N₄). Compared to the double-recessed (DR) structure, the saturation current, the transconductance, the breakdown voltage, the maximum oscillation frequency (f_max), the maximum power added efficiency and the maximum theoretical output power density (P_max) of the novel structure is increased by 24%, 21%, 9%, 11%, 14% and 34%, respectively. Therefore, the novel structure has excellent performance and has a broader application prospect than the double recessed structure.

SUBMITTER: Jia H

PROVIDER: S-EPMC8146966 | biostudies-literature |

REPOSITORIES: biostudies-literature

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