A novel 4H-SiC MESFET with serpentine channel for high power and high frequency applications

In this paper, a novel 4H-SiC metal semiconductor field effect transistor with serpentine channel (SC-MESFET) is proposed which the gate-drain drift region shifts downward integrally compared to the gate-source drift region. With the depth of the gate-drain shift increasing, the channel electric field and the gate depletion layer have been modulated. The simulated results show that the drain saturation current and breakdown voltage of the SC-MESFET are about 21.5% and 46.7% larger than that of the conventional double-recessed 4H-SiC MESFET (DR-MESFET). The gate-source capacitance of proposed structure is also improved from 0.59 pF/mm to 0.51 pF/mm and the DC transconductance of the SC-MESFET is very close to that of the DR-MESFET at the bias conditions of Vgs = 0 V and Vds = 40 V, which results in better RF characteristics. All of the results show that the novel 4H-SiC MESFET with serpentine channel has superior electrical characteristics and performances.