Drift Velocity Calculation in Si Using an Analytical Model for the Phonon Dispersion

M. Gada, D. Vasileska, K. Raleva, S.M. Goodnick
Arizona State University, US

Keywords: silicon, drift velocity


It is well known that crystalline silicon is the material of choice for fabrication of integrated circuits because silicon wafers are cheap and silicon dioxide is abundant in nature. Properties of the crystalline silicon have been explored extensively both experimentally and theoretically. In the theoretical calculations non-parabolic bands and full-band bulk Monte Carlo calculations have been used. Phonons have been treated either using the Debye approximation for the acoustic modes and the Einstein relation for the optical modes or full phonon dispersions have been calculated using the rigid ion approximation. In a recent work by Pop and co-workers analytical model for the phonon dispersion has been used in conjuncture with non-parabolic model which is quite accurate for current state of the art devices because the supply voltages are on the order of 1 V or smaller. The choice of the scattering processes was determined using a rejection algorithm, which sometimes tends to be time consuming. To overcome this and obtain results faster, in this work an analytical model for the scattering rates has been used that utilizes the full phonon dispersion.