Oriented graphene nanoribbons embedded in hexagonal boron nitride trenches

Chunxiao Cong,Tianru Wu,Lingxiu Chen,Daoli Zhang,Shujie Tang,Hui Shan Wang,Lei Li,Xiaoming Xie,Haomin Wang,Ting Yu,Mianheng Jiang,Li He,Lianwen Deng,Hong Xie,Hui Xia,Tianxin Li

doi:10.1038/ncomms14703

Abstract

Graphene nanoribbons (GNRs) are ultra-narrow strips of graphene that have the potential to be used in high-performance graphene-based semiconductor electronics. However, controlled growth of GNRs on dielectric substrates remains a challenge. Here, we report the successful growth of GNRs directly on hexagonal boron nitride substrates with smooth edges and controllable widths using chemical vapour deposition. The approach is based on a type of template growth that allows for the in-plane epitaxy of mono-layered GNRs in nano-trenches on hexagonal boron nitride with edges following a zigzag direction. The embedded GNR channels show excellent electronic properties, even at room temperature. Such in-plane hetero-integration of GNRs, which is compatible with integrated circuit processing, creates a gapped channel with a width of a few benzene rings, enabling the development of digital integrated circuitry based on GNRs.

Highlights

Graphene nanoribbons (GNRs) are ultra-narrow strips of graphene that have the potential to be used in high-performance graphene-based semiconductor electronics
In the GNR samples, the band gap exhibited a strong dependence on the width of the ribbons
The electronic structure of GNRs is strongly dependent on the edge of the GNRs

Summary

Introduction

Graphene nanoribbons (GNRs) are ultra-narrow strips of graphene that have the potential to be used in high-performance graphene-based semiconductor electronics. We report the successful growth of GNRs directly on hexagonal boron nitride substrates with smooth edges and controllable widths using chemical vapour deposition. The approach is based on a type of template growth that allows for the in-plane epitaxy of mono-layered GNRs in nano-trenches on hexagonal boron nitride with edges following a zigzag direction. The embedded GNR channels show excellent electronic properties, even at room temperature. The capability to precisely produce GNRs with defined chirality at the atomic level is required in order to engineer their band gap and electrical properties[2,3]. Electronics always require scalable transfer-free approaches for growing GNRs and conducting band gap engineering. We demonstrate the successful growth of GNRs directly on h-BN substrates with smooth edges and controllable widths via templated growth using chemical vapour deposition (CVD). The crystallographically selective chemical reaction indicates lower activation energy along the ZZ patterns of the h-BN

Methods

Results

Conclusion