Calculation of electron drift velocity at Si avalanche

In evaluating the electron drift velocity at Si avalanche, the electron distribution is obtained by solving the Boltzmann transport equation in the maximum anisotropy truncation (MAT) approximation of Baraff. Improvements are made to the MAT procedure so that the symmetrical part of the distribution function can be obtained in a straightforward manner. The temperature dependence of electron drift velocity is studied by including both optical phonon emission and absorption rather than emission alone. The calculated electron drift velocity varies from
1 \times 10^{7}
to
2.9 \times 10^{7}
cm/s at Si avalanche.