Thermal simulation techniques for nanoscale transistors

Thermal simulations are important for advanced electronic systems at multiple length scales. A major challenge involves electrothermal phenomena within nanoscale transistors, which exhibit nearly ballistic transport both for electrons and phonons. The thermal device behavior can influence both the mobility and the leakage currents. We discuss recent advances in modeling coupled electron-phonon transport in future nanoscale transistors. The solution techniques involve solving the Boltzmann transport equation (BTE) for both electrons and phonons. We present a practical method for coupling an electron Monte Carlo simulation with an analytic "split-flux" form of the phonon BTE. We use this approach to model self-heating in a 20 nm quasi-ballistic n+/n/n+ silicon diode, and to investigate the role of hot electron and hot phonon transport.