Investigation of Spurious Velocity Overshoot Using Monte Carlo Data

For the simulation of state-of-the-art devices hydrodynamic and energy transport models allow to account for non-local effects which cannot be captured by the drift-diffusion model. Although these models have been available for several decades, there are still unresolved issues. One of these issues is the occurrence of spurious peaks in the velocity profile which have originally been related to Blotekjær's model. Recent research, however, showed that these peaks are inherent to both Stratton's and Bletekjær's model. We investigate the origin of these peaks by introducing relaxation times, mobilities, and closure relations directly from a coupled Monte Carlo simulator. Although accurate modeling of the relaxation times and mobilities is important, it appears that the origin of the spurious peaks lies in the truncation of the infinite series of moments.