Enabling Principles for Manufacturing van der Waals Heterostructures with Clean Interfaces

New York University, New York NY

Investigators

Abstract

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.