Decoupling the Graphene Buffer Layer from SiC(0001) via Interface Oxidation
Epitaxial graphene (EG) grown on SiC(0001) resides on the so-called buffer layer. This carbon rich (6√3×6√3)R30° reconstruction is covalently bound to the topmost silicon atoms of the SiC. Decoupling the graphene buffer layer from the SiC interface is a well studied topic since successful intercalation has been shown for hydrogen [1-3]. Recently, intercalation was also shown for oxygen [4, 5]. We present ARPES, XPS and Raman spectroscopy studies to determine the quality of oxygen intercalated buffer layer samples in terms of decoupling and integrity of the transformed graphene layer. The decoupling effect is demonstrated by ARPES measurements showing a graphene-like π band. XPS shows whether the oxidation takes place in the buffer layer or at the interface. Raman spectroscopy is well suited to investigate oxygen induced defects in graphene-like material.
Robert P. Devaty, Michael Dudley, T. Paul Chow and Philip G. Neudeck
M. Ostler et al., "Decoupling the Graphene Buffer Layer from SiC(0001) via Interface Oxidation", Materials Science Forum, Vols. 717-720, pp. 649-652, 2012