Growth of monolayer graphene on 8deg off-axis 4H-SiC (000-1) substrates with application to quantum transport devices

TL;DR

This study demonstrates the growth of high-quality monolayer graphene on off-axis 4H-SiC substrates, exhibiting properties suitable for quantum transport applications and integration with existing SiC device technology.

Contribution

It introduces a method for growing large, homogeneous monolayer graphene on off-axis SiC with confirmed high quality and quantum Hall effects.

Findings

High carrier mobility in graphene layers

Observation of half-integer Quantum Hall effect

Moderate p-type doping levels

Abstract

Using high temperature annealing conditions with a graphite cap covering the C-face of an 8deg off-axis 4H-SiC sample, large and homogeneous single epitaxial graphene layers have been grown. Raman spectroscopy shows evidence of the almost free-standing character of these monolayer graphene sheets, which was confirmed by magneto-transport measurements. We find a moderate p-type doping, high carrier mobility and half integer Quantum Hall effect typical of high quality graphene samples. This opens the way to a fully compatible integration of graphene with SiC devices on the wafers that constitute the standard in today's SiC industry.