Size-dependent electron mobility in InAs nanowires

This work studies the electron mobility in InAs nanowires, taking into account the contribution of the main scattering mechanisms that determine its behavior. Moreover, we analyze its dependence on the nanowire diameter, carrier density and population of the Γ, L and X valleys. It is found that surface roughness and polar optical phonons are the scattering mechanisms that mainly limit the mobility behavior. We also show that the electron mobility of the L valleys is much lower than the one of the Γ valley, because of the higher conduction effective mass. The combination of the higher population of the L valleys and the stronger impact of the surface roughness scattering degrades the characteristic high mobility of InAs as the nanowire diameter decreases.