Thermal Modeling of Multi-finger SiC Power MESFETs

The self-heating phenomena of one- and multi-fingered SiC MESFETs were studied through 2D electro-thermal simulations and 2D and 3D steady-state thermal simulations. The device performance degradation caused by selfheating was observed, and is more profound for devices operating at room temperature than for devices working at elevated temperatures. The junction temperature and temperature distribution of devices fabricated on SiC substrates were estimated through both electro-thermal simulations and steady-state thermal simulations, and the results agree well. Different layouts and gate pitches were investigated to optimize the trade-off between maximum operating temperature and the longest signal path, which limits the size of high-frequency devices