Nanofabrication research pursues the miniaturization of patterned feature size. In the current state of the art, micron scale areas can be patterned with features down to ~30 nm pitch using electron beam lithography. Here, we demonstrate a nanofabrication technique which allows patterning periodic structures with a pitch down to 16 nm. It is based on focused ion beam milling of suspended membranes, with minimal proximity effects typical to standard electron beam lithography. The membranes are then transferred and used as hard etching masks. We benchmark our technique by electrostatically inducing a superlattice potential in graphene and observe bandstructure modification in electronic transport. Our technique opens the path towards the realization of very short period superlattices in 2D materials, but with the ability to control lattice symmetries and strength. This can pave the way for a versatile solid-state quantum simulator platform and the study of correlated electron phases.

纳米制造研究追求图案特征尺寸的小型化。在当前的技术水平下，可以使用电子束光刻技术对微米级区域进行图案化，其特征间距​​小至约 30 nm。在这里，我们展示了一种纳米加工技术，该技术允许对节距低至 16 nm 的周期结构进行图案化。它基于悬浮膜的聚焦离子束铣削，具有最小的标准电子束光刻典型的邻近效应。然后将膜转移并用作硬蚀刻掩模。我们通过在石墨烯中静电感应超晶格电势来对我们的技术进行基准测试，并观察电子传输中的能带结构变化。我们的技术开辟了在二维材料中实现极短周期超晶格的道路，但具有控制晶格对称性和强度的能力。这可以为多功能固态量子模拟器平台和相关电子相的研究铺平道路。