Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo, 153-8505, Japan.
National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki, 305-0044, Japan.
Nat Commun. 2018 Apr 12;9(1):1413. doi: 10.1038/s41467-018-03723-w.
Van der Waals heterostructures are comprised of stacked atomically thin two-dimensional crystals and serve as novel materials providing unprecedented properties. However, the random natures in positions and shapes of exfoliated two-dimensional crystals have required the repetitive manual tasks of optical microscopy-based searching and mechanical transferring, thereby severely limiting the complexity of heterostructures. To solve the problem, here we develop a robotic system that searches exfoliated two-dimensional crystals and assembles them into superlattices inside the glovebox. The system can autonomously detect 400 monolayer graphene flakes per hour with a small error rate (<7%) and stack four cycles of the designated two-dimensional crystals per hour with few minutes of human intervention for each stack cycle. The system enabled fabrication of the superlattice consisting of 29 alternating layers of the graphene and the hexagonal boron nitride. This capacity provides a scalable approach for prototyping a variety of van der Waals superlattices.
范德华异质结构由堆叠的原子层状二维晶体组成，是提供前所未有性能的新型材料。然而，剥离二维晶体在位置和形状上的随机性，需要基于光学显微镜的重复手动搜索和机械转移任务，从而严重限制了异质结构的复杂性。为了解决这个问题，我们开发了一种机器人系统，该系统可以在手套箱内搜索剥离的二维晶体并将它们组装成超晶格。该系统可以自主检测每小时 400 个单层石墨烯薄片，错误率（<7%）低，并且可以每小时堆叠四个循环的指定二维晶体，每个堆叠循环只需要几分钟的人工干预。该系统能够制造由 29 个交替的石墨烯和六方氮化硼层组成的超晶格。这种能力为各种范德华超晶格的原型设计提供了一种可扩展的方法。
