Two-dimensional atomic layer materials are strong candidate materials for semiconductor and energy device technologies. When stacked together three-dimensional heterogeneous nanostructures are formed. Owing to weak vertical interaction between two-dimensional materials, their heterostructures display unique device functionality and novel physical phenomena. However, it has been extremely challenging to fabricate such two-dimensional building blocks and three-dimensional heterostructures from them due to a lack of methodology to control layer numbers and limited manufacturing scale. This award supports both modeling and experimental research to develop a low-cost nanomanufacturing process of wafer-scale two-dimensional materials-based heterostructures through exfoliation and transfer. This technology offers unique features of enabling preparation of a wide range of freestanding monolayer two-dimensional materials and providing the potential for heterogeneous integration at wafer-scale. The success of this project broadly impacts high performance, atomically-thin semiconductor device technologies, such as new transistors, solar cells, light emitting diodes (LEDs), photodetectors, lasers, and sensors that could touch every aspect of daily life. Therefore, results from this research benefits both the U.S. economy and society. The project's broader impacts plans involve learning to apply textbook theories to industrial applications through intensive nano-engineering lab modules, which includes results from the exfoliation and transfer process to fabricate heterostructures of 2D materials.
The proposed Layer Resolved Splitting (LRS) process enables manufacturing of wafer-scale heterogeneously integrated two-dimensional (2D) atomic layer building blocks by precisely controlling the exfoliation and transfer of a wide variety of 2D materials. The research team demonstrates the feasibility of the LRS technique to manufacture multiple monolayer materials at wafer-scale by performing "one growth" of multiple layers of 2D materials on the wafer. Furthermore, the proposed dry stacking process substantially improves the performance of wafer-scale heterostructures compared to heterostructures prepared by wet stacking. Eventually, this project opens up new opportunities in 2D materials research by providing a reliable platform to manufacture monolayer-resolved wafer-scale 3D heterostructures.
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.