Department of Chemistry, University of Illinois at Urbana−Champaign, 1206 West Green Street, Urbana, Illinois 61801, USA.
ACS Nano. 2010 Oct 26;4(10):5591-8. doi: 10.1021/nn101896a.
Here we report a technique for transferring graphene layers, one by one, from a multilayer deposit formed by epitaxial growth on the Si-terminated face of a 6H-SiC substrate. The procedure uses a bilayer film of palladium/polyimide deposited onto the graphene coated SiC, which is then mechanically peeled away and placed on a target substrate. Orthogonal etching of the palladium and polyimide leaves isolated sheets of graphene with sizes of square centimeters. Repeating these steps transfers additional sheets from the same SiC substrate. Raman spectroscopy, scanning tunneling spectroscopy, low-energy electron diffraction and X-ray photoelectron spectroscopy, together with scanning tunneling, atomic force, optical, and scanning electron microscopy reveal key properties of the materials. The sheet resistances determined from measurements of four point probe devices were found to be ∼2 kΩ/square, close to expectation. Graphene crossbar structures fabricated in stacked configurations demonstrate the versatility of the procedures.
在这里，我们报告了一种从通过在 6H-SiC 衬底的 Si 终止面上外延生长形成的多层沉积物中单层转移石墨烯层的技术。该方法使用沉积在涂覆有石墨烯的碳化硅上的钯/聚酰亚胺双层膜，然后将其机械剥离并放置在目标衬底上。钯和聚酰亚胺的正交蚀刻留下具有平方厘米尺寸的孤立石墨烯片。重复这些步骤可从同一 SiC 衬底转移更多的石墨烯片。拉曼光谱、扫描隧道光谱、低能电子衍射和 X 射线光电子能谱，以及扫描隧道显微镜、原子力显微镜、光学显微镜和扫描电子显微镜揭示了材料的关键特性。通过四点探针器件测量确定的片电阻约为 2 kΩ/平方，接近预期值。以堆叠配置制造的石墨烯交叉结构证明了这些方法的多功能性。
