Van der Waals (vdW) dielectrics are widely used in nanoelectronics to preserve the intrinsic properties of two-dimensional (2D) semiconductors. However, achieving aligned growth of 2D semiconductors and their direct utilization on original vdWs epitaxial dielectrics to avoid disorders poses significant challenges.

To overcome these challenges, researchers from the City University of Hong Kong (CityUHK) developed a hydromechanical strategy for aligned 2D material synthesis, pushing forward high-performance devices with as-grown 2D materials/vdWs dielectrics.

“Directly utilizing 2D semiconductors on their as-grown substrates is significant in avoiding disorder-induced performance degradation of electronic devices. Our progress in this work ingeniously avoids the traditional material transfer process, which has substantial technological implications for unlocking the transformative potential of 2D materials,” explained Professor Johnny Ho, associate vice president (enterprise) and professor in the Department of Materials Science and Engineering at CityUHK, who led the study.

Leveraging the hydromechanical strategy developed in this study, the research team can control the preferential orientations of 2D materials on vdWs dielectrics. This breakthrough is highly significant, as it allows for the direct utilization of as-grown 2D materials on vdW dielectrics at the device level, minimizing the detrimental effects caused by disorder-induced performance degradation.

Additionally, establishing the quantitative criterion for the epitaxy relationship with vdWs dielectrics can be aptly viewed as a measure of our understanding and can guide experimental decisions effectively. This finding opens up exciting opportunities for realizing next-generation electronics on vdW dielectric platforms.

The imperative to mitigate disorder-induced performance degradation in electronic devices has driven demand for the direct utilization of as-grown 2D materials/vdW dielectric.

“However, the paradox is that the as-grown 2D materials are meticulously detached from the original substrates onto proposed dielectrics for further device fabrication,” said Professor Ho.

With this powerful methodology platform for synthesizing aligned 2D materials, predicting alignment directions, and preserving their intrinsic properties, future research can leverage this knowledge to develop novel manufacturing techniques, enabling the production of high-performance electronic devices with enhanced functionality, reliability, and scalability. Such devices may include large-scale integrated circuits, flexible and wearable electronics, advanced optoelectronic devices, Quantum technologies, etc.

Looking ahead, the research team aims primarily to transfer this technique to other 2D material systems to investigate their inherent properties and explore potential avenues for large-scale device integration. These endeavours aim to unlock further the transformative potential of aligned 2D materials on van der Waals dielectrics for developing innovative electronic devices.

The findings, titled “Orientation-engineered 2D electronics on van der Waals dielectric”, were published in the scientific journal Matter.

Dr. Weijun Wang, Yuanxuan Zhang, and Dr. Wei Wang from CityUHK are the co-first authors. Professor Ho and Professor Weida Hu from the State Key Laboratory of Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai, China are the corresponding authors. Other collaborators include Professor Sen Po Yip from the Institute for Materials Chemistry and Engineering, Kyushu University, Japan.

For enquiry, please contact Professor Ho by email at [email protected].