Electrical and thermal analysis of vertical unidirectional 3C-SiC/Si MESFETs on silicon substrate

The performance of a Unidirectional Normally-on 3C-SiC/Si power MESFET is analyzed. The electrical characteristics are simulated using the industry standard Silvaco Atlas simulator. Thermal analysis and self-heating are investigated using COMSOL, the most advanced Multiphysics simulator. The electrical analysis shows that the drain current of this device is 100% higher than a lateral device with the same dimensions, while occupying less than 33% of the area. The study shows that for a gate voltage of 0V, the drain current reaches 600mA/mm; the breakdown voltage reaches more than 600V; and the critical breakdown electric field increases to 3.9×10⁶V/cm. The Thermal analysis is conducted using the Si substrate as a heat sink, with T=300K. The drain current was set 600 mA/mm and the drain voltage at 600V. The results show that highest surface temperature due to self-heating does not exceed 312K.