SusCheM: Directed Covalent Assembly of Nanodiamonds into Films for MEMS Applications

金刚石薄膜由于其耐磨损、化学稳定性、低摩擦系数、低热膨胀系数、宽光学透明度、生物相容性和可调节的导电性，在许多成熟和新兴的技术领域发挥着重要作用，包括制造工具、保护涂层和高功率电子产品。由于类似的原因，金刚石薄膜也开始引起研究人员的注意，用于微机电系统（MEMS），如传感器和执行器。然而，除了性能之外，这些薄膜的可扩展性、可持续性和成本也是影响其广泛使用可行性的因素。该奖项支持基础研究，为开发一种新型金刚石膜生长工艺提供所需的知识，该工艺：(1)几乎可以在任何衬底上进行，包括金属、氧化物和塑料；(2)由于原材料的低成本和现成可用性而具有经济性；(3)对健康的危害更小，对环境安全；(4)可以与标准半导体技术集成。这种具有可定制物理特性的低成本、可扩展的金刚石薄膜将在能源、制造业、医疗保健、传感器、电子和其他重要应用领域产生广泛影响，从而对美国经济和社会产生积极影响。此外，这种涉及化学、材料科学、制造和工程研究的多学科方法将对扩大少数民族参与研究以及将纳米材料制造概念纳入K-12课程产生重大影响。纳米金刚石定向共价组装的概念，使用通用的室温化学来形成保形和致密的薄膜，将为MEMS的新型可持续涂层铺平道路。共价组装纳米金刚石薄膜的全部应用潜力可以通过克服调整其物理性质（机械、热学和光学）的科学障碍来实现，这些物理性质与薄膜微/纳米结构中孔隙度的水平和分布直接相关。本研究旨在通过在薄膜制备过程和制备后退火过程中对纳米金刚石骨料尺寸的精确控制来填补孔隙率减少机制方面的知识空白。研究团队将使用最先进的材料表征方法来表征孔隙度分布和相关的物理特性。此外，微加工器件将以纳米金刚石薄膜为载体，展示其与MEMS的集成，以促进物理性质（如平面内和平面间导热性）的量化，并将这些发现与直接共价组装过程中使用的纳米金刚石聚集体尺寸相关联。

Diamond thin films play an important role in many established and emerging areas of technology including manufacturing tools, protective coatings, and high power electronics due to their increased resistance to wear, chemical stability, low coefficient of friction, low coefficient of thermal expansion, wide optical transparency, biocompatibility, and tunable conductivity. For similar reasons, diamond thin films have also started attracting attention from researchers for use in microelectromechanical systems (MEMS) such as sensors and actuators. However, besides performance the scalability, sustainability, and cost of these films are also factors that influence their viability for widespread use. This award supports fundamental research to provide needed knowledge for the development of a novel diamond film growth process that: (1) can be performed virtually on any substrate, including metals, oxides, and plastics, (2) is economical due to low cost and ready availability of the raw material, (3) poses lower health hazards and is environmentally safe, and (4) can be integrated with standard semiconductor technology. Such low cost, scalable diamond films with tailorable physical properties will enable broad impact in energy, manufacturing, healthcare, sensors, electronics, and other important applications, thus providing a positive impact on the U.S. economy and society. In addition, this multi-disciplinary approach involving research in chemistry, materials science, manufacturing, and engineering will provide a significant impact on broadening participation of minorities in research, and incorporating nanomaterial manufacturing concepts in K-12 curriculum.The concept of directed covalent assembly of nanodiamonds using versatile, room-temperature chemistry to form conformal and compact films will pave the way to a novel class of sustainable coatings for MEMS. The full application potential of covalently assembled nanodiamond films can be achieved by overcoming the scientific barrier of tuning its physical properties (mechanical, thermal, and optical) which are directly linked to the level and distribution of porosity in the film micro-/nanostructure. This research seeks to fill the knowledge gap on the mechanism(s) of porosity reduction through precise control over nanodiamond aggregate size during film fabrication as well as post-fabrication anneal. The research team will characterize porosity distribution and the associated physical properties using state-of-the-art materials characterization methods. Further, microfabricated devices will be made with the nanodiamond films as a vehicle to demonstrate its integration into MEMS, to facilitate quantification of physical properties such in-plane and cross-plane thermal conductivity, and to correlate these findings to the nanodiamond aggregate sizes used during the direct covalent assembly process.