Nanolithography and manipulation of graphene using an atomic force microscope(8)

oxidation process. Additionally, the hydrophobic character of graphite will repel water necessary to from a meniscus between tip and substrate during the oxidation procedure. This hydrophilic behavior of a graphene surface is clearly visible in Fig. 5, where the high environmental humidity (58%) leads to the formation of water droplets, (indicated by the circle) on top of a single layer graphene sheet [34]. These droplets only form on the hydrophobic graphene, but not on the more hydrophilic SiO2 substrate where rather a homogeneous wetting by a water film takes place. As a consequence, we can observe a stripe of water along the edges of the graphene sheet (dotted line in Fig 5, see also Fig. 4) which will substantially ease oxidation from the edges.

3. Conclusions

In summary, we have shown that it is possible to use an AFM to nano-manipulate individual layers of graphene either by means of mechanical peeling or by electrochemical oxidation. Local anodic oxidation proved to be an extremely useful manner to manipulate graphene. By oxidizing grooves of less than 30 nm wide in a graphene sheet it is in principle possible to cut out every structure imaginable, e.g. quantum point contacts or quantum dots, making this technique very promising for table top graphene based devise fabrication.

搜索“diyifanwen.net”或“第一范文网”即可找到本站免费阅读全部范文。收藏本站方便下次阅读，第一范文网，提供最新工程科技Nanolithography and manipulation of graphene using an atomic force microscope(8)全文阅读和word下载服务。