NONEQUILIBRIUM TRANSPORT IN NANOSCALE SEMICONDUCTOR DEVICES

Soon, semiconductor devices will utilize very short gate lengths, of order 10-30 nm. These devices are expected to be dominated by quasi-ballistic, quantum transport in the active region. Simulation has developed as a major tool for predictive behavior of new devices, particularly with kinetic transport handled via a multi-particle Monte Carlo approach. Initial quantum effects have been incorporated into such simulations via an effective potential approach with great success, and we will discuss the application to small fully-depleted silicon-on-insulator devices. As devices grow smaller, however, more advanced techniques, such as the non-equilibrium Green’s functions (NEGF) must be utilized, although there are constraints upon these approaches that must be incorporated into modeling of small devices. Nevertheless, approaches which derive from NEGF, such as the Wigner distribution function, can still be implemented via the kinetic Monte Carlo approaches. The application of this approach to the modeling of a resonant tunneling diode also is discussed. The inclusion of both collisional broadening and the intra-collisional field effect into a Monte Carlo simulation of the Wigner function transport is described.