Enabling Principles for Manufacturing van der Waals Heterostructures with Clean Interfaces

一类新的人工材料可以通过多个二维(2D)材料的分层组装而获得，这种材料被称为范德华异质结构。这些异质结构为新电子学的发展提供了广阔的前景。近年来，在制造具有大面内尺寸的不同2D材料方面取得了相当大的科学技术进步。然而，将这些材料分层组装成具有干净界面的类似尺寸的异质结构仍然具有挑战性。具体地说，由这些异质结构制成的电子需要层之间极其干净的界面才能发挥预期的作用。该项目将建立制备界面干净、尺寸大的范德华异质结的新策略。该奖项通过促进量子材料和器件的跨学科领域，支持纽约大学创造新的教育和研究机会，并与NSF量子飞跃的伟大理念保持一致：通过开发有可能实现新量子技术的材料系统和器件来引领下一次量子革命。该项目将教育研究生和本科生，并为他们在工业或学术生涯中的职业做好准备，同时旨在扩大不同背景的学生的参与，重点是那些在STEM中代表性不足的学生。当这些材料被构建成具有干净界面的异质结构时，2D材料的许多令人兴奋的物理特性都会显现出来。然而，制造这些异质结构的主要障碍是无法从组装2D材料时产生的界面上去除聚合物残基。这项研究将从能量的角度研究聚合物污染异质结构的界面清洁机理，从而填补这方面的知识空白。为此，该项目将研究三个主要原则：1)聚合物残留物与2D材料的相互作用，2)聚合物残留物在界面上的动员，以及3)通过设计弹性印章来机械驱动已动员的残留物。这项研究将以石墨烯和二硫化钼为载体的异质结构为测试载体，以聚乙烯醇和石蜡为例进行聚合物污染。研究团队将建立聚合物污染异质结构中的界面清洁机制，并创建具有宏观维度的清洁异质结构。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

A new class of artificial materials can be obtained through the layered assembly of multiple two-dimensional (2D) materials, known as van der Waals heterostructures. These heterostructures are promising for the development of new electronics. In recent years, considerable scientific and technological progress has occurred toward producing different 2D materials with large in-plane dimensions. However, the layered assembly of those materials into similarly sized heterostructures with clean interfaces remains challenging. Specifically, electronics made from those heterostructures require an extremely clean interface between the layers in order to function as desired. This project will establish new strategies for fabricating van der Waals heterostructures with clean interfaces and large dimensions. This award supports the creation of new educational and research opportunities at New York University by fostering the interdisciplinary area of quantum materials and devices and aligns with the NSF Big Idea of Quantum Leap: Leading the Next Quantum Revolution by developing material systems and devices that have the potential to enable new quantum technologies. The project will educate graduate and undergraduate students and prepare them for industrial or academic careers, while aiming to broaden the participation of students with different backgrounds, emphasizing those who are underrepresented in STEM.Many exciting physical properties of 2D materials manifest when these materials are built into heterostructures with clean interfaces. However, a primary barrier to manufacturing these heterostructures is the inability to remove polymeric residues from the interfaces that arise when assembling the 2D materials. This research will help fill the knowledge gap on mechanisms for the interface cleaning of polymer-contaminated heterostructures by studying this problem from an energy viewpoint. To this end, the project will examine three major principles: 1) interactions of polymer residues with 2D materials, 2) mobilization of polymer residues at the interfaces, and 3) mechanical actuation of the mobilized residues through engineering an elastomeric stamp. This research will use heterostructures based on graphene and molybdenum disulfide as test vehicles and employ polyvinyl alcohol and paraffin as examples for the polymeric contaminations. The research team will establish the mechanisms of interface cleaning in polymer-contaminated heterostructures and create clean heterostructures with macroscopic dimensions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.