Theoretical Investigation of the Electrical Behavior of SiC MESFETs for Microwave Power Amplification

The electrical behavior of 3C, 4H, and 6H SiC MESFETs has been simulated using an analytical two region transistor model which takes into account the nonlinear v-E characteristics, incomplete ionization, and self heating. The results show that the 4H SiC polytype is best suited for microwave power MESFETs, but 3C and 6H SiC also seem to be useful materials for this purpose. Using Si instead of SiC al the subtrate material causes increased channel temperatures and a deterioration of the transistor performance at high gate-source voltages.