Lithography-Free Manufacturing of Metal Structures Separated by Nanogaps

该基金支持的研究将推进制造技术和知识基础，这些技术和知识基础是由纳米级距离（称为纳米间隙）的金属结构组成的光学和电子元件的片上制造所必需的。尽管概念验证应用于化学和生物医学传感、纳米电子学和光伏，但基于纳米间隙的器件加工的进展受到技术要求高、耗时和成本高昂的技术的阻碍。此外，目前的方法在生成完全表达纳米间隙相关现象所需的结构方面还远远不够理想。该奖项旨在通过将片上纳米隙制造工艺从不可避免的复杂工艺转变为提供合成简易性和前所未有的控制，同时响应制造环境的低成本，高通量和可扩展性需求，从而纠正这种情况。所开展的研究将通过研究生培训、本科生研究实习、实验室模块以及参与促进多样性、公平和包容的成熟项目的个人指导，整合到教育活动中。因此，总体目标是促进对社会健康和福祉具有重要意义的应用，同时培训实施前沿技术所需的多样化劳动力。该奖项的目标是定义芯片上处理由低于5纳米的纳米间隙分隔的对立金属表面所需的台式技术，因为它们与等离子体和分子电子学有关。特别针对的是(i)二聚体阵列的制造，其中纳米间隙被分子连接物占据，（ii）具有充满空气的纳米间隙的二聚体阵列，以及（iii）通过纳米间隙沿其长度不连续的桥连接的图案电极。这些都形成了一个整体策略指导下的研究推力，其中纳米压印提供了确定性定位，间隔材料定义了纳米隙宽度，通过液态合成形成的结构通过与间隔材料对接形成纳米隙。间隔材料的使用对整个方法至关重要，因为纳米间隙的定义不依赖于光刻技术，而是依赖于易于应用于单层尺度精度的材料。这样的能力，一旦被证明，将为将纳米隙集成到应用平台提供一条前进的道路，并为研究人员社区原型设计最先进的设备提供新的能力。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。

This grant supports research that will advance the manufacturing techniques and knowledge base required for the on-chip fabrication of optical and electronic components composed of metal structures separated by nanometer-scale distances referred to as nanogaps. Despite proof-of-concept applications in chemical and biomedical sensing, nanoelectronics, and photovoltaics, progress in nanogap-based device processing is hampered by the need for technically demanding, time-consuming, and cost-prohibitive techniques. Moreover, current methods are far from ideal in terms of generating the configurations needed to fully express nanogap-related phenomena. This award aims to remedy this situation by transforming on-chip nanogap fabrication from processes that are inextricably complicated to those offering synthetic ease and unprecedented control while at the same time being responsive to the low-cost, high-throughput, and scalability needs of a manufacturing setting. The research carried out will be integrated into educational activities through graduate student training, undergraduate research internships, lab modules, and the mentorship of individuals participating in well-established programs promoting diversity, equity, and inclusion. The overall aim is, therefore, to advance applications of importance to the health and well-being of society while training the diverse workforce needed to enact leading-edge technologies. The objective of the award is to define the benchtop techniques required for the on-chip processing of opposing metal surfaces separated by sub-5 nm nanogaps as they relate to plasmonics and molecular electronics. Specifically targeted is the fabrication of (i) dimer arrays where the nanogap is occupied by molecular linkers, (ii) dimer arrays with air-filled nanogaps, and (iii) patterned electrodes connected by a bridge with a nanogap discontinuity along its length. Each of these forms a research thrust guided by an overall strategy in which nanoimprinting provides for deterministic positioning, a spacer material defines the nanogap width, and structures formed through liquid-state syntheses form a nanogap by butting up against a spacer material. The use of a spacer material is crucial to the overall approach in that nanogap definition is reliant, not on lithography, but on materials that are readily applied with monolayer-scale precision. Such capabilities, once demonstrated, will provide a path forward for integrating nanogaps into application platforms and provide new capabilities to the community of researchers prototyping state-of-the-art devices.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.