Low-temperature quantum transport in CVD-grown single crystal graphene

TL;DR

This study demonstrates that CVD-grown single crystal graphene exhibits electronic properties at low temperatures comparable to exfoliated graphene, with high mobility and observable quantum Hall effects, indicating high quality suitable for practical applications.

Contribution

The paper provides a detailed analysis of the electronic properties of high-quality CVD-grown single crystal graphene, showing its superior performance over polycrystalline graphene and its similarity to exfoliated graphene.

Findings

Mobility up to 11000 cm²/Vs in CVD graphene

Observation of over 12 quantum Hall plateaus

Inelastic scattering length exceeds 1 μm at charge neutrality

Abstract

Chemical vapor deposition (CVD) has been proposed for large-scale graphene synthesis for practical applications. However, the inferior electronic properties of CVD graphene are one of the key problems to be solved. In this study, we present a detailed study on the electronic properties of high-quality single crystal monolayer graphene. The graphene is grown by CVD on copper using a cold-wall reactor and then transferred to Si/SiO2. Our low-temperature magneto-transport data demonstrate that the characteristics of the measured single-crystal CVD graphene samples are superior to those of polycrystalline graphene and have a quality which is comparable to that of exfoliated graphene on Si/SiO2. The Dirac point in our best samples is located at back-gate voltages of less than 10V, and their mobility can reach 11000 cm2/Vs. More than 12 flat and discernible half-integer quantum Hall plateaus have been observed in high magnetic field on both the electron and hole side of the Dirac point. At low magnetic field, the magnetoresistance shows a clear weak localization peak. Using the theory of McCann et al., we find that the inelastic scattering length is larger than 1 {\mu}m in these samples even at the charge neutrality point.