Multi-Band Mobility in Semiconducting Carbon Nanotubes

TL;DR

This paper introduces a new compact model for the mobility of single-wall carbon nanotubes, highlighting how mobility varies with diameter, temperature, and charge density, and establishing an upper limit at room temperature.

Contribution

It provides a simple two-parameter mobility model based on experimental data, revealing the impact of subband scattering on mobility limits.

Findings

Mobility increases with nanotube diameter.

Mobility decreases with temperature.

Room temperature mobility is capped at around 10,000 cm2/V.s at high carrier densities.

Abstract

We present new data and a compact mobility model for single-wall carbon nanotubes, with only two adjustable parameters, the elastic and inelastic collision mean free paths at 300 K. The mobility increases with diameter, decreases with temperature, and has a more complex dependence on charge density. The model and data suggest the room temperature mobility does not exceed 10,000 cm2/V.s at high carrier density (n > 0.5 nm-1) for typical single-wall nanotube diameters, due to the strong scattering effect of the second subband.