Morphology of Graphene on SiC(000-1) Surfaces

TL;DR

This paper investigates the morphological differences of graphene grown on SiC(000-1) surfaces compared to SiC(0001), revealing terraced versus flat structures and the formation of nanocrystalline graphite on some wafers.

Contribution

It provides a comparative analysis of graphene morphology on different SiC surfaces and links morphological differences to interface structures.

Findings

Graphene on C-face forms terraced structures.

Graphene on Si-face exhibits flatter morphology.

Nanocrystalline graphite can form on top of graphene.

Abstract

Graphene is formed on SiC(000-1) surfaces (the so-called C-face of the crystal) by annealing in vacuum, with the resulting films characterized by atomic force microscopy, Auger electron spectroscopy, scanning Auger microscopy and Raman spectroscopy. Morphology of these films is compared with the graphene films grown on SiC(0001) surfaces (the Si-face). Graphene forms a terraced morphology on the C-face, whereas it forms with a flatter morphology on the Si-face. It is argued that this difference occurs because of differing interface structures in the two cases. For certain SiC wafers, nanocrystalline graphite is found to form on top of the graphene.