Subband Structure of Silicon Nanowires from the Hensel-Hasegawa-Nakayama Model

The subband structure of nanowires is commonly obtained through an atomistic tight binding approach. In this work an alternative, continuum based method is investigated, namely a two-band k ·p approximation of the conduction band structure. A derivation of the subband Schrödinger equations from the bulk model and their numerical solution are presented for [100] nanowires. Self-consistent simulation results of exemplary devices are examined and the influence of confinement on the band structure is discussed. For nanowire thicknesses below ten nanometers band structure effects similar to those observed using atomistic models become apparent.