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arXiv · 1503.08588

Why graphene growth is very different on the C face than on the Si face of SiC: Insights from surface equilibria and the (3$\times$3)-3C-SiC($\bar{\text{1}}\bar{\text{1}}\bar{\text{1}}$) reconstruction

Lydia Nemec·Florian Lazarevic·Patrick Rinke·Matthias Scheffler·Volker Blum
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Abstract

We address the stability of the surface phases that occur on the C-side of 3C-SiC($\bar{1} \bar{1} \bar{1}$) at the onset of graphene formation. In this growth range, experimental reports reveal a coexistence of several surface phases. This coexistence can be explained by a Si-rich model for the unknown (3$\times$3) reconstruction, the known (2$\times$2)$_{C}$ adatom phase, and the graphene covered (2$\times$2)$_{C}$ phase. By constructing an $ab$ $initio$ surface phase diagram using a van der Waals corrected density functional, we show that the formation of a well defined interface structure like the "buffer-layer" on the Si side is blocked by Si-rich surface reconstructions.

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Lydia Nemec, Florian Lazarevic, Patrick Rinke, Matthias Scheffler, Volker Blum. 2015-03-30. Why graphene growth is very different on the C face than on the Si face of SiC: Insights from surface equilibria and the (3$\times$3)-3C-SiC($\bar{\text{1}}\bar{\text{1}}\bar{\text{1}}$) reconstruction. https://doi.org/10.1103/physrevb.91.161408

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