Abstract: Small-signal high frequency characteristics of 4H-SiC MESFETs have been studied with the two-dimensional device simulator MEDICI based on the operation model of 4H-SiC MESFETs developed in this paper. The simulation results using teh sinusoidal steady-state analysis approach agree well with the experimental data within the cut-off frequency. Also, the effects of the gate length, gate-to-drain spacer distances, inpruity concentration and lemperature on the high frequency characteristic of SiC MESFETs have been studied based on the presented model.

Key words: 4H-SiC, MESFET, high frequency small-signal, cut-off frequency