Determination of the graphene growth mode on SiC(0001) and SiC(000-1)

TL;DR

This study investigates how graphene grows on SiC surfaces by tracking isotopic markers, revealing that new layers form underneath existing ones during thermal decomposition.

Contribution

It provides direct experimental evidence of the growth mode of graphene on SiC(0001) and SiC(000-1) using isotopic labeling techniques.

Findings

13C predominantly in outermost graphene layers

Graphene layers form underneath existing layers during decomposition

Growth mode consistent on both Si-face and C-face surfaces

Abstract

We have determined the growth mode of graphene on SiC(0001) and SiC(000-1) using ultra-thin, isotopically-labeled Si13C `marker layers' grown epitaxially on the Si12C surfaces. Few-layer graphene overlayers were formed via thermal decomposition at elevated temperature. For both surface terminations (Si-face and C-face), we find that the 13C is located mainly in the outermost graphene layers, indicating that, during decomposition, new graphene layers form underneath existing ones.