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arXiv · 1103.6160

Multilayer epitaxial graphene formed by pyrolysis of polycrystalline silicon-carbide grown on c-plane sapphire substrates

Timothy J. McArdle·Jack O. Chu·Yu Zhu·Zihong Liu·Mahadevaiyer Krishnan·Christopher M. Breslin·Christos Dimitrakopoulos·Robert Wisnieff·Alfred Grill
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Abstract

We use ultra-high vacuum chemical vapor deposition to grow polycrystalline silicon carbide (SiC) on c-plane sapphire wafers which are then annealed between 1250 and 1450°C in vacuum to create epitaxial multilayer graphene (MLG). Despite the surface roughness and small domain size of the polycrystalline SiC, a conformal MLG film is formed. By planarizing the SiC prior to graphene growth, a reduction of the Raman defect band is observed in the final MLG. The graphene formed on polished SiC films also demonstrates significantly more ordered layer-by-layer growth and increased carrier mobility for the same carrier density as the non-polished samples.

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Timothy J. McArdle, Jack O. Chu, Yu Zhu, Zihong Liu, Mahadevaiyer Krishnan, Christopher M. Breslin, Christos Dimitrakopoulos, Robert Wisnieff, Alfred Grill. 2011-03-31. Multilayer epitaxial graphene formed by pyrolysis of polycrystalline silicon-carbide grown on c-plane sapphire substrates. https://doi.org/10.1063/1.3575202

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