Electrothermal simulation of power vdmos transistors

Poisson’s equation and the electron continuity equation, together with heat flow equation are solved self‐consistently to obtain the lattice temperature profile under non‐isothermal conditions in a power VDMOS transistor. The effect of the variable lattice temperature on the forward characteristics of VDMOSTs is presented, and discussed. The results show that self‐heating in power VDMOSTs has a significant effect. The thermal coupling effects on the forward I—V characteristics are compared and discussed between the power VDMOST and the conventional MOSFET.