EAGER: Transfer by Contact using Adhesion Engineering for Integration of Two-Dimensional Materials into Functional Devices

石墨烯的发现导致了具有多种独特性质的原子薄二维材料的发现。二维材料已迅速成长为下一代电子、光电子和量子器件的主要材料平台之一。为了将这些材料集成到功能器件中，它们需要与生长基质分离，并在不损坏和污染的情况下转移到目标表面。这种材料集成是具有挑战性的，通过目前的转移技术，通常依赖于使用额外的支持层湿和高温工艺来实现。这个探索性研究（EAGER）项目旨在通过开发和理解一种干燥和低温工艺来克服这些挑战，这种工艺可以通过一次直接接触和分层步骤将二维材料从源直接转移到目标，而不需要支持层。这种技术可以帮助减少转移过程中的损坏和污染，以实现其他难以实现的可扩展和高通量方式的结构。因此，这个转移平台可以帮助促进我国在快速发展的二维材料及其应用领域的全球竞争力。这个研究项目将为这一领域的学生提供培训机会。本研究成果将直接作为实验教学模块整合到正在开发的新课程中。本研究的目的是开发一种干燥、低温、牺牲的单层二维材料的无层转移。在这种方法中，当源和目标表面接触并在受控条件下使用对齐的转移印刷平台分层时发生转移。其基础是目标基材表面的工程设计，其相互作用和粘附机制超越了促进成功转移的范德华力。该项目将开发这种用于二维单层转移的方法，重点关注表面粘附工程，通过调整表面化学末端和机械特性，研究粘附机制，探测转移质量，并相应地优化无损伤和无污染的转移。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The discovery of graphene has led to the discovery of atomically thin two-dimensional materials with diverse and unique properties. Two-dimensional materials have rapidly grown into one of the leading material platforms for next-generation electronics, optoelectronics and quantum devices. For these materials to be integrated into functional devices, they need to be isolated from their growth substrate and transferred onto a target surface without damage and contamination. This materials integration is challenging to achieve through the current transfer techniques which generally rely on wet and high temperature processes using additional support layers. This EArly-concept Grant for Exploratory Research (EAGER) project looks to overcome these challenges by developing and understanding a dry and low-temperature process that allows direct transfer of two-dimensional materials from a source to target by a single direct contact and delamination step without a need for a support layer. Such a technique can help reduce damage and contamination during the transfer to achieve otherwise hard to realize structures in a scalable and high-throughput manner. As a result, this transfer platform can help in promoting our nation’s global competitiveness in the rapidly evolving field of two-dimensional materials and their applications. This research program will provide opportunities for training students in this area. The results of this research will be directly integrated as a laboratory teaching module in a new course being developed. The aim of this research is to develop a dry, low-temperature, sacrificial layer-free transfer of monolayer two-dimensional materials. In this approach, transfer occurs as the source and target surfaces are brought into contact and delaminated under controlled conditions using an aligned transfer printing platform. Foundational to this is engineering of the target substrate surface with interactions and adhesion mechanisms beyond van der Waals forces that promote a successful transfer. This EAGER will develop this approach for 2D monolayer transfer with a focus on surface adhesion engineering through tuning the surface chemical terminations and mechanical characteristics, studying the adhesion mechanisms, probing the transfer quality and accordingly optimizing for a damage and contamination-free transfer.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.