Abstract: Dual-channel 4H-SiC MESFET is optimized for high power microwave applications.Physics-based analytical models for the device are obtained by solving one- and two-dimensional Poisson's equations.Direct-current (DC) and alternating-current (AC) performances of the 4H-SiC MESFET are calculated.The result is in agreement with experimental data.Calculated maximum saturation current density and breakdown voltage are about 420 μA·μm^-1 and 155 V,respectively,which are greater than those of dual-channel structure,275 μA·μm^-1 and 141 V.Resultant maximum output power density is 7.4 W·mm^-1,which is 64% higher than that of dual-channel structure.Cutoff frequency and the maximum oscillation frequency are slightly improved.The power performance is significantly improved while its AC characteristics are not degraded.

Key words: H-SiC, MESFETs, Poisson's equation