Consistent comparison of drift-diffusion and hydro-dynamic device simulations

Due to the ongoing downscaling of devices non-local effects become more and more important. These non-local effects can be considered in a device simulator using a hydrodynamic (HD) transport model. However, solving the equation system resulting from a HD transport model is known to be much more expensive in computational terms compared to the simpler drift-diffusion (DD) transport model. Thus the HD model should only be used when really necessary in order not to waste valuable computational resources. However, the validity of the DD model must be carefully investigated which is subject to this paper