Hydrogenated monolayer graphene with reversible and tunable wide band gap and its field-effect transistor.

Sanghoon Kim,Sang Jin Kim,Jangyup Son,Jongill Hong,Jae Hoon Kim,Han-Koo Lee,Byung Hee Hong,Byung Cheol Park,Soogil Lee

doi:10.1038/ncomms13261

Abstract

Graphene is currently at the forefront of cutting-edge science and technology due to exceptional electronic, optical, mechanical, and thermal properties. However, the absence of a sizeable band gap in graphene has been a major obstacle for application. To open and control a band gap in functionalized graphene, several gapping strategies have been developed. In particular, hydrogen plasma treatment has triggered a great scientific interest, because it has been known to be an efficient way to modify the surface of single-layered graphene and to apply for standard wafer-scale fabrication. Here we show a monolayer chemical-vapour-deposited graphene hydrogenated by indirect hydrogen plasma without structural defect and we demonstrate that a band gap can be tuned as wide as 3.9 eV by varying hydrogen coverage. We also show a hydrogenated graphene field-effect transistor, showing that on/off ratio changes over three orders of magnitude at room temperature.

Highlights

Graphene is currently at the forefront of cutting-edge science and technology due to exceptional electronic, optical, mechanical, and thermal properties
The absence of a sizeable band gap in graphene synthesized by the present technologies and experimental challenges originating from the intrinsic nature and extrinsic degradation of graphene are impeding further developments in envisioned carbon-based electronics
We show that monolayer graphene hydrogenated by indirect hydrogen plasma at room temperature acquires a band gap up to B4.0 eV that can be tuned by varying hydrogen coverage while preserving the structural integrity of the original graphene

Summary

Introduction

Graphene is currently at the forefront of cutting-edge science and technology due to exceptional electronic, optical, mechanical, and thermal properties. We first demonstrate that the intrinsic band-gapped graphene we created fully functions as a field-effect transistor (FET), showing that conductivity at gate voltages changes over three orders of magnitude at room temperature.

Results

Conclusion