论文标题
钻石（111）表面重建和外延石墨烯界面
The Diamond (111) Surface Reconstruction and Epitaxial Graphene Interface
论文作者
论文摘要
通过角度分辨光发射光谱，低能量电子衍射和互补密度的功能理论计算，研究了钻石表面（111）表面的演变（111）表面的演变。从C（111） - （2x1）进行表面重建开始，该过程在920°C脱离后发生，并在1000°C以上的温度下脱离了重建的表面原子的释放，直至将重建的表面原子释放为单层的免费单层单层。我们的结果表明，C（111） - （2x1）表面是金属的，因为它具有与费米级相交的电子状态。这与对称的π键模型非常吻合，应该有助于解决该表面电子性质的文献中存在的争议。在新形成的C（111） - （2 \ times1）表面上存在于较高温度下形成的石墨烯，并且由于在Fermi-Level处观察到DIRAC点时似乎几乎没有底物相互作用。最后，我们证明，可以通过血浆加工而无需去除石墨烯层，从而形成石墨烯 - 轴向导剂界面，从而通过血浆处理终止了基础钻石表面。这对于通过可调底物相互作用在钻石表面形成的石墨烯可能具有特殊意义，因为通过血浆处理改变了钻石 - 格拉烯界面处的终端物种。
The evolution of the diamond (111) surface as it undergoes reconstruction and subsequent graphene formation is investigated with angle-resolved photoemission spectroscopy, low energy electron diffraction, and complementary density functional theory calculations. The process is examined starting at the C(111)-(2x1) surface reconstruction that occurs following detachment of the surface adatoms at 920 °C, and continues through to the liberation of the reconstructed surface atoms into a free-standing monolayer of epitaxial graphene at temperatures above 1000 °C. Our results show that the C(111)-(2x1) surface is metallic as it has electronic states that intersect the Fermi-level. This is in strong agreement with a symmetrically π-bonded chain model and should contribute to resolving the controversies that exist in the literature surrounding the electronic nature of this surface. The graphene formed at higher temperatures exists above a newly formed C(111)-(2\times1) surface and appears to have little substrate interaction as the Dirac-point is observed at the Fermi-level. Finally, we demonstrate that it is possible to hydrogen terminate the underlying diamond surface by means of plasma processing without removing the graphene layer, forming a graphene-semiconductor interface. This could have particular relevance for doping the graphene formed on the diamond (111)surface via tuneable substrate interactions as a result of changing the terminating species at the diamond-graphene interface by plasma processing.
