Evolution of morphology and defects of graphene with growth parameters by PECVD

Abstract

The morphology of graphene has an important impact on its applications such as sensing and energy storage. In this study, the evolution of the surface morphology and defect types of graphene that was directly grown on Al2O3 by plasma enhanced chemical vapor deposition (PECVD) was investigated by controlled growth conditions. It was found that the defect type of graphene was determined by the ion source power while the surface morphology of graphene was determined by the combination of growth temperature and ion source power. The type of defects of graphene changed from vacancy-like to boundary-like as the ion source power increased, and the morphology of graphene changed from two-dimensional (2D) to three-dimensional (3D) as the temperature rose or the power of the ion source increased. The hydrophobicity of graphene was well correlated with surface morphology, in which the contact angle of graphene changes from 78° to 132° with the change of graphene from 2D to 3D.