Hall Effect Mobility of Epitaxial Graphene Grown on Silicon Carbide

TL;DR

This study measures the Hall effect mobility and carrier densities of epitaxial graphene grown on silicon carbide, revealing face-dependent properties and potential for high mobility applications.

Contribution

It provides detailed measurements of Hall effect mobility and carrier densities of epitaxial graphene on SiC, highlighting face-dependent differences and scattering mechanisms.

Findings

Mobility reaches ~150,000 cm2V-1s-1 on (000-1) face at 300 K.

Mobility is higher at lower carrier densities, regardless of carrier type.

Approximately 40% of samples show holes as the dominant carrier.

Abstract

Epitaxial graphene films were grown in vacuo by silicon sublimation from the (0001) and (000-1) faces of 4H- and 6H-SiC. Hall effect mobilities and sheet carrier densities of the films were measured at 300 K and 77 K and the data depended on the growth face. About 40% of the samples exhibited holes as the dominant carrier, independent of face. Generally, mobilities increased with decreasing carrier density, independent of carrier type and substrate polytype. The contributions of scattering mechanisms to the conductivities of the films are discussed. The results suggest that for near-intrinsic carrier densities at 300 K epitaxial graphene mobilities will be ~150,000 cm2V-1s-1 on the (000-1) face and ~5,800 cm2V-1s-1 on the (0001) face.