ABSTRACT
This chapter examines the nature of phonon generation in silicon at several strengths of applied electric field. Identifying trends in phonon emission spectra at high fields is crucial to enabling more thermally efficient devices. The relationship between phonon energy and momentum is usually presented by the phonon dispersion relationship. This relationship bears some similarity to the usual electron dispersion, better known as the band diagram. The dispersion was calculated using an adiabatic bond charge model. The model was suggested nearly three decades ago as an alternative to the similar valence shell models. The model itself consists of representing the lattice vibrations as 3D forces between the four types of interactions: nearest-neighbor ion, bond-charge, coulomb and bond-bond. The rate of change of the phonon distribution can be computed by integrating the scattering rate over all electron momenta. Phonon transport is described by the Boltzmann transport equation, which describes the evolution in time of the phonon distribution function.
