Department of Materials Science and Engineering and Materials Research Institute, The Pennsylvania State University, University Park, PA 16802, United States of America. Center for Two Dimensional and Layered Materials, The Pennsylvania State University, University Park, PA 16802, United States of America.
Nanotechnology. 2018 Jan 12;29(2):025602. doi: 10.1088/1361-6528/aa9c21.
The effective use of the van der Waals 2D materials relies on their successful transfer from the growth substrate onto other target substrates in the form of large films or flakes. In particular, it is important to transfer such atomically thin samples to various substrates with minimal sample damage and exposure to etchants and chemicals to realize their applications. Here we develop a universal transfer method that not only is free of reactive etchants, but also can maintain the film morphology intact with no tears and cracks. We show a variety of different 2D crystals and thin films with various sizes and thicknesses transferred from different substrates, i.e. metal-organic chemical vapor deposition-grown WSe coalesced thin films on sapphire and mechanically exfoliated 2D crystalline flakes on titanium nitride. Further examination by transmission electron microscopy indicates successful transfer of all the samples. This study presents a universal and etchant-free transfer method that can be used to transfer a variety of 2D crystals and other nanostructures from/to various substrates.
范德华 2D 材料的有效利用依赖于它们从生长衬底成功转移到其他目标衬底上，形成大片或薄片的形式。特别是，将这些原子级薄的样品转移到各种衬底上，以最小化样品损伤并避免暴露于蚀刻剂和化学物质，对于实现它们的应用非常重要。在这里，我们开发了一种通用的转移方法，不仅没有反应性蚀刻剂，而且可以保持薄膜形态完整，没有撕裂和裂缝。我们展示了各种不同的二维晶体和薄膜，它们的尺寸和厚度各不相同，从不同的衬底上转移过来，例如在蓝宝石上通过金属有机化学气相沉积生长的 WSe 合并薄膜和在氮化钛上机械剥离的二维晶体薄片。进一步通过透射电子显微镜检查表明所有样品都成功转移。这项研究提出了一种通用且无蚀刻剂的转移方法，可以用于从各种衬底上转移各种二维晶体和其他纳米结构。
