Non-Destructive Laser-Induced Transfer of Nanostructures to Flexible Substrates with Sub-5 Nanometer Resolution

这项拨款支持一种新的制造工艺的基础研究，用于纳米级结构的增材转移，这种结构的直径比人类头发的直径小一千倍。该工艺使用激光非破坏性地提升纳米结构，并将其以低于5纳米的精度放置在柔性基板上。这个过程是负担得起的，因为它可以在环境条件下完成。这种能力对于可穿戴设备、传感器和其他柔性电子产品等应用非常重要，它们的经济制造促进了国家的繁荣和安全。增材制造或三维打印被工程师和设计师广泛用于快速原型定制产品。不幸的是，这种快速成型技术还没有发展到纳米尺度和柔性基板。纳米级制造的重要性在于材料在如此小的尺度上所表现出的非凡特性。因此，制造三维纳米结构的能力对于探索纳米材料的新特性和应用变得至关重要。柔性基板上可靠且具有成本效益的纳米结构和设备制造对于可穿戴设备的生产越来越重要，预计到2022年全球市场将达到500亿美元。该奖项支持纳米级三维打印的研究，可以在柔性基材上实现二维和三维纳米结构的快速原型制作。该奖项还使妇女和未被充分代表的少数族裔学生广泛参与研究和教育以及下一代劳动力的STEM培训。本研究的增材纳米制造方法克服了传统纳米制造方法普遍存在的成本高、耗时长、与柔性基板不兼容以及缺乏定制性等诸多局限性。这项研究利用低成本连续波激光器的局部加热来提升几乎任何形状和大小的纳米结构。通过精确的电子操作，提升的纳米结构被转移并添加到柔性、保形或刚性基板上，非破坏性地形成分辨率低于5nm的3D和3D纳米尺度图案。整个制造过程在环境条件下进行，不需要高压或真空，这使得它具有成本效益。该项目涉及精确的位置和温度测量，以研究该制造过程的基本机制。采用光学前向散射检测方法定量测量了提升纳米结构的初始速度和角分布。用温敏发光探头测量制造过程中的局部温度。展示了在柔性衬底上具有高精度纳米级间隙的互补、二维和三维纳米结构的选择性和相容性纳米制造。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 the fundamental study of a new manufacturing process for additive transfer of nanometer-sized structures that are a thousand times smaller than the diameter of a human hair. The process uses a laser to lift the nanostructure non-destructively and place it with sub-5 nanometer precision on a flexible substrate. The process is affordable because it can be done under ambient conditions. Such a capability is important for applications such as wearables, sensors, and other flexible electronics, the economic manufacture of which advances the prosperity and security of the nation. Additive manufacturing or three-dimensional printing is widely used by engineers and designers for rapid prototyping customizable products. Unfortunately, such a rapid prototyping technique is yet to be developed for the nanoscale and for flexible substrates. The importance of manufacturing at the nanoscale lies in the extraordinary properties that materials exhibit at such small scales. Therefore, the ability to manufacture three-dimensional nanometer-sized structures becomes critically important to explore new properties and applications of nanomaterials. Reliable and cost-effective manufacturing of nanostructures and devices on flexible substrates has become increasingly important for the production of wearable devices with a worldwide market expected to reach USD 50 Billion by 2022. This award supports research on nanoscale three-dimensional printing that can enable rapid prototyping of both two-dimensional and three-dimensional nanostructures on flexible substrates. This award also enables broad participation of women and underrepresented minority students in research and education and STEM training of the next-generation workforce.The additive nanomanufacturing method in this research overcomes many limitations that commonly exist in conventional nanomanufacturing methods, which are high-cost, time-consuming, incompatibility with flexible substrates, and lack of customization. This research utilizes localized heating from a low-cost continuous-wave laser to lift-off nanostructures of virtually any shape and size. Through precise electrical manipulation, the lifted nanostructures are transfered and additively placed on flexible, conformal or rigid substrates, non-destructively, to form 3D and 3D nanoscale patterns with sub-5nm resolution. The whole manufacturing process happens under ambient conditions without the need of high-voltage or vacuum, which makes it cost-effective. The project involves precise position and temperature measurements to study the fundamental mechanisms for this manufacturing process. The initial speed and angular distribution of the lifted nanostructures are measured quantitatively by using optical forward scattered detection. The localized temperature in the manufacturing process is measured with temperature sensitive luminescent probes. Selective and compatible nanomanufacturing of complementary, 2D and 3D nanostructures, with high precision nano-scale gaps on flexible substrates are demonstrated.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.