Nano-Mechanics of Solid Surface Suspension and Imprinting

固体表面悬浮和压印的纳米力学Kyung-Suk Kim，工程学教授布朗大学，普罗维登斯，RI 02912由于每平方英寸的钉子密度很高，人可以躺在钉子床上而不会受到伤害，因为人的身体悬浮在钉子接触点上。然而，如果施加足够的压力，指甲会刺穿皮肤表面。这种现象也可以在纳米尺度上观察到。在某些条件下，固体表面悬浮在密集的纳米结构阵列上，而在其他条件下，表面被纳米结构阵列压印。在这个项目中，研究人员和他的同事们研究了纳米级固体表面变形与固体表面悬浮和压印引起的高接枝密度接触和分子相互作用在界面上。高接枝密度的碳纳米管阵列，大于每平方毫米亿阵列，用于研究塑性变形固体的纳米级接触悬浮和高密度纳米级接触的压印性。这项研究的动机是需要开发有效的技术制造表面纳米结构，并打算进一步了解纳米摩擦和磨损。前者包括纳米压印以及纳米平面化的金模具的纳米压印光刻。纳米压印光刻不仅可以制作极小的特征，而且可以大大简化许多生产工艺，大大降低生产成本。半导体工业目前正在开发纳米压印光刻技术，以构建具有窄至30纳米宽度或更小的电路的芯片。后者主要包括用于干加工的纳米结构的固体润滑。无液体润滑剂的干式加工是为大规模生产轻质结构建立环境安全的制造基础设施所必需的。汽车工业目前正在开发一种纳米结构涂层的工具表面加工铝零件的干摩擦系数低至0.02或更低的智力价值的工作是在纳米接触界面变形的机制提供基本的理解，并建立一个系统的框架，评估可靠性的纳米制造和使用固体纳米结构。在更广泛的影响方面，惠普公司的斯坦威廉姆斯说，“压印技术有可能彻底改变半导体工业以及许多其他领域，从数据存储到光学网络到生命科学”，这表明对信息技术和纳米技术的潜在重大影响。此外，它将对生物和环境技术产生广泛的影响，表面纳米结构传感器和过滤器，以及材料，制造和能源技术，纳米结构碳基涂层用于干式加工轻质结构。此外，在该项目下，计划通过暑期实习计划教育代表性不足的REU学生，并开发纳米力学领域的新课程。

Nano-mechanics of solid surface suspension and imprintingKyung-Suk Kim, Professor of EngineeringBrown University, Providence, RI 02912Given a high density of nails per square inch, a person is able to lie upon a bed of nails without harm, as the body of the person is suspended on the nail contact points. However, if enough pressure is applied, the nails will pierce the skin surface. This phenomenon can also be observed at the nanometer-scale. Under certain conditions, a solid surface is suspended on a dense array of nanostructures while at other conditions, the surface is imprinted by the nanostructure array. In this project, the investigator and his colleagues study nanometer-scale solid surface deformation associated with solid surface suspension and imprinting caused by high grafting density contacts and molecular interactions at the interface. Carbon nanotube arrays of high grafting density, greater than hundred million arrays per square millimeter, are used to study nanoscale contact suspension of plastically deforming solids and imprintability of high density nanoscale contacts. The study is motivated by the need to develop effective technology for fabricating surface nanostructures and intended to further understanding of nanoscale friction and wear. The former includes nano-imprinting as well as nano-planarization of gold molds for nano-imprinting lithography. Nano-imprinting lithography can not only produce extremely small features but greatly simplify many production processes and lower production cost substantially. The semiconductor industry is currently developing nano-imprinting lithography to build chips with circuits as narrow as 30 nanometers width or less. The latter comprises mainly solid lubrication with nanostructures for dry machining. Dry machining, without liquid lubricant, is necessary to build environmentally-safe manufacturing infrastructures for mass production of lightweight structures. The automotive industry is currently developing a nano-structured coating on tool surfaces to machine aluminum parts with the dry friction coefficient as low as 0.02 or less.The intellectual merit of the work is to provide fundamental understanding of mechanisms of contact interface deformation at the nanoscale and to establish a systematic framework for assessing reliability of nano-fabrication and the use of solid nanostructures. In terms of broader impact, Stan Williams of Hewlett-Packard has stated, "imprint technology has the potential to revolutionize the semiconductor industry as well as a host of other fields, from data storage to optical networking to life sciences," indicating potential major impact on information technology as well as on nano-technology. In addition, it will make broad impact on bio and environmental technology with surface nano-structure sensors and filters, and on materials, manufacturing and energy technology with nanostructured carbon-based coatings for dry machining of light weight structures. Also under this project, it is planned to educate under-represented REU students through summer internship programs and to develop a new course in the field of nanomechanics.