Epitaxial Graphene Grown on 4H-SiC with Excess Electrons Provided by Electron Beam Irradiation

Abstract

Epitaxial graphene (EG) growth on SiC substrate is one of the most intensively investigated graphene production methods. Compared with other methods, it has the advantage of scalability as EG can be grown in wafer-scale, beneficial for industrial applications. Conventional EG growth on SiC by using thermal annealing requires heating an entire substrate to very high temperatures (>1300℃). Instead, EG growth with electron beam (e-beam) irradiation demonstrated that EG can be grown at lower temperatures (<1000℃). However, the electron mobility is typically smaller than the value of the conventional annealing. Here, we report the enhanced electrical properties of EG grown on 4H-SiC(0001) substrate, including its electron mobility of ~994 cm2/Vs, by optimizing the parameters of e-beam irradiation. Additionally, the density functional theory calculations show that the injected electrons can reduce the cohesive energy of SiC, triggering the early sublimation of Si atoms and leading to the EG growth at relatively low temperatures.

NRF- 2023R1A2C1006519