Derivation of Macroscopic Equations

In this chapter we explain the strategy how to derive macroscopic models from the semiconductor Boltzmann equation by the so-called moment method. The macroscopic models contain only averaged physical quantities. A main assumption of the derivation of the transport equations is that scattering of the electrons is (in some sense) dominant. Then, depending on the considered timescale, hydrodynamic or diffusive fluid-type models are derived.