Investigation of Microdevice Performance by Transient Heat Transfer Simulation

The present work considers transient electrothermal simulation of sub-micrometer silicon device and electron-phonon interactions in electrical and thermal fields. A coupled thermal and electrical model is developed for a silicon n+-n -n+ structure consisting of the hydrodynamic equations for electron transport and energy conservation equations for phonon. The results indicate that, for one electric field the lattice temperature gradient has significant effect on the magnitude of electric current. The transient phonon temperature affects the device performance due to the change of mobility and gradient temperature of electron. At an external voltage of 0.1 V, calculations show that an increase in the junction boundary temperature by 100 (degree)C, cause increasing the drain current by 16% at 3 picosecond and decreases it by 17% up to steady state condition.