COMPARISON OF NON-PARABOLIC HYDRODYNAMIC MODELS BASED ON DIFFERENT BAND-STRUCTURE MODELS

This paper presents two non-parabolic hydrodynamic model formulations suitable for the simulation of inhomogeneous semiconductor devices. Th e first formulation uses the Kane dispersion relationship, ((h) over b ar)k(2)/2m = W(l+alpha W). The second formulation makes use of a power law, ((h) over bar k)(2)/2m = xW(y), for the dispersion relation. The non-parabolicity and energy range of the hydrodynamic model based on the Kane dispersion relation is limited. The power law formulation pro duces closed form coefficients similar to those under the parabolic ba nd approximation but the carrier concentration can deviate. An extende d power law dispersion relation is proposed to account for band struct ure effects, ((h) over bar k)(2)/2m = xW(1+yW). This dispersion relati on closely matches the calculated band structure over a wide energy ra nge and may lead to closed form coefficients for the hydrodynamic mode l.