Efficient Monte Carlo device modeling

A single-particle approach to full-band Monte Carlo device simulation is pr esented which allows an efficient computation of drain, substrate and gate currents in deep submicron MOSFETs, In this approach, phase-space elements are visited according to the distribution of real electrons. This scheme is well adapted to a test-function evaluation of the drain current, which emp hasizes regions with large drift velocities (i.e., in the inversion channel ), a substrate current evaluation via the impact ionization generation rate (i.e., in the LDD region with relatively high electron temperature and den sity) and a computation of the gate current in the dominant direct-tunnelin g regime caused by relatively cold electrons (i.e, directly under the gate at the source well of the inversion channel). Other important features are an efficient treatment of impurity scattering, a phase-space steplike propa gation of the electron allowing to minimize self-scattering, just-before-sc attering gathering of statistics, and the use of a frozen electric field ob tained from a drift-diffusion simulation. As an example an 0.1-mu m n-MOSFE T is simulated where typically 30 minutes of CPU time are necessary per bia s point for practically sufficient accuracy.