Effects of Functionalization and Stress on Graphene Electronic Properties: Focusing on Bandgap

Xiaohan Ming,O.P Malik

doi:10.1051/e3sconf/202123101007

Abstract

Graphene is considered as a promising base material for nanodevices due to the excellent mechanical, thermal and electronic properties. However, when developing 2D semiconductor device such as a field-effect transistor, one obstacle we are facing is the zero bandgap of pure graphene, which makes it hard to apply to the semiconductor field. In this study, we verify the feasibility of opening the bandgap by functionalizing a graphene and adding stresses based on first principle calculations, where hydroxyl and epoxy groups are used. The effect on bandgap is also observed in the calculations after adding stress about a few GPa. The results show that bandgaps of 1~2 eV in functionalized graphene were opened and stresses of 1GPa induced slightly variations of bandgaps. The electron density differences indicate that the loaded functional groups take away the charge of graphene, making it a betatopic system. Our study may provide a potential method to modify the electronic properties of two-dimensional materials.

Highlights

The development of artificial intelligence (AI) and the fifth-generation mobile communication technologies spawns the demand of next-generation electron devices which requires miniaturization, low energy consumption and high frequency [1,2]
Its charge carriers act like massless Dirac fermions which can switch between electrons and holes under certain voltage, and its special structure makes it unnecessary to rearrange its atoms for adjusting to external stress
We demonstrate the effects of functional groups and stress to modulate bandgap of graphene based on a first principle calculation

Summary

Introduction

The development of artificial intelligence (AI) and the fifth-generation mobile communication technologies spawns the demand of next-generation electron devices which requires miniaturization, low energy consumption and high frequency [1,2]. A traditional Si-based complementary metal-oxide-semiconductor (CMOS) transistor has a theoretical limit of 5 nm due to the rapidly decrease of carrier mobility with the thickness [3,4,5,6]. Some two-dimension materials, including transition metal disulfide (TMD) compounds and their heterojunction based field-effect transistors (FETs), have been proposed [7,8,9]. Graphene has the potential to become the ideal replacement for the silicon-based nanodevice because of the superior electronic and mechanic properties [10,11]. Unlike TMDs as direct-gap semiconductors, the zero bandgap of graphene prohibits many promising applications in the semiconductor field. It will be helpful for us to develop a regulative bandgap which can be modulated by the external influence that we exert

Methods

Results

Conclusion