Coupled Monte Carlo simulation of transient electron-phonon transport in nanoscale devices

Using a coupled Monte Carlo method for solving both electron and phonon Boltzmann transport equations, the transient electrothermal behaviors of nanoscale Si n-i-n device are simulated. The nonequilibrium optical phonon distribution is characterized by a temperature different from that of the acoustic phonons, and these two temperatures show different characteristics not only in the steady state, but also in transient conditions. It has been also suggested that the simulated transient response of the phonon temperatures can be practically described by the equivalent thermal circuit model, which is useful for, e.g., projecting the NBTI lifetime during the realistic circuit operations.