Scalable Synthesis and Metrology of Epitaxial Graphene on SiC

石墨烯是一种单原子石墨层，具有特殊的电子特性，例如能够以极高的速度携带电荷，这使得这种新的纳米材料对下一代电子设备具有吸引力。然而，合成和表征这种超薄材料尤其具有挑战性。提出了碳化硅（SiC）单晶的激光照射作为石墨烯合成方法。激光吸收导致SiC的分解和硅的选择性蒸发，在表面上留下石墨烯层。使用斯坦福大学同步加速器源的X射线束，将研究激光合成的石墨烯层的晶体完整性和取向。此外，石墨烯层的键合缺陷将被光谱学研究。最后，通过在照射过程中屏蔽部分激光束，演示一步合成和图案化。拥有一种可以扩展到大晶片（类似于硅）的石墨烯合成方法的社会效益将非常显著。事实上，使大面积的石墨烯适合于制造设备是开发这种材料的主要挑战之一。此外，参与该项目的学生将接受材料科学方面的培训，这种新材料可能在下一代先进电子设备中发挥作用。还计划通过位于斯坦福的NSF中心的中学教师暑期研究所开展外展活动，以探索纳米尺度，并通过开发可导入课堂环境的实践活动。

Graphene, a single-atom-think layer of graphite, has exceptional electronic qualities, such as the ability to carry charge at great speed, that make this new nanomaterial attractive for the next generation of electronic devices. Synthesizing and characterizing such ultra-thin material however is especially challenging. Laser irradiation of a single-crystal of silicon carbide (SiC) is proposed as a graphene synthesis method. Laser light absorption causes the decomposition of the SiC and selective evaporation of silicon leaving a graphene layer on the surface. Using the x-ray beam at the Stanford Synchrotron source crystalline perfection and orientation of the laser-synthesized graphene layer will be investigated. Furthermore, bonding defects of the graphene layer will be investigated spectroscopically. Finally, one-step synthesis and patterning will be demonstrated by masking parts of the laser beam during irradiation.The societal benefits of having a graphene synthesis method that can be scaled to large wafers, similarly to silicon, would be very significant. Indeed, making large areas of graphene suitable for the fabrication of devices is one of the main challenges to the development of this material. Furthermore, students working on the project would be trained in the Materials Science of a novel material that is likely to play a role in the next generation of advanced electronic devices. Outreach activities are also planned through the summer institute for middle-school teachers at the Stanford-based NSF center for probing the nanoscale and through the development of hands-on activities that can be exported into a classroom environment.