Correlation between three-dimensional current distribution profiles and surface scatterings in nanostructured materials

Abstract

Intensive heat generation associated with surface scattering is a major obstacle for minimizing high performance electronic circuit components beyond submicron scale, a regime in which the device length scale is comparable to the electron inelastic scattering mean free path. In this work, the fundamental physics of surface scattering during the electrical transport process is addressed by quantum mechanical modeling of the current distribution profile in a three-dimensional conduction channel. The results show that the surface potentials act as local scatters that deflect the current from the topmost surface layer, leading to an accumulation of the current density in the subsurface layer. The possible size dependency in such a current distribution profile is proposed based on the scaling theory in weak localization regime. It suggests that for Gaussian-like surface potential profile, the inelastic scattering mean free path decreases as the full width half maximum of the potential profile increases. Surface scatterings are also likely to play an important role in producing the resistivity of extremely narrow conducting channels.