GOALI: Stable Nanomechanical Oscillators with Large f*Q Product

'1.提案标题：GOALI：具有大f*Q的稳定纳米机械振荡器产品2。项目目标简介：将在金刚石中制造纳米级电光机械系统，并探索其在精密测量（例如质量，力）中的应用。3.翻译后摘要：a）非技术摘要：金刚石是一种迷人的材料，具有许多显着的性能。事实上，在许多方面，它是最终的工程材料-工程师最好的朋友！例如，金刚石具有很高的机械硬度，是最好的热导体之一。它是从紫外线到远红外线的光学透明的，并且具有高折射率（n = 2.4）。最后，它具有生物相容性和化学惰性。这些特性使金刚石成为许多应用中非常理想的材料，包括生命科学，石油勘探和工业传感。这些应用中的许多要求实现高频（f）、高品质因数（Q）、稳定的纳米级机电和光机械系统（NEMS和NOMS）。这些系统可以实现稳定的振荡器和灵敏的质量测量，并且可以在恶劣的环境（由于金刚石的化学惰性）和生物医学环境（由于金刚石的生物相容性）中操作。然而，尽管单晶金刚石具有独特的性能，但它在NEMS和NOMS中的应用还不多！为什么？为什么？所有NEMS/ NOMS平台都有一个共同的重要特征：它们由一个器件层组成，通常是一个由不同材料的衬底支撑的薄膜，可以通过化学方法去除。单晶金刚石是来自广泛的材料列表的一个示例，许多材料具有吸引人的材料特性，对于这些材料不存在这种薄膜平台。为了克服这一障碍，该团队将利用角蚀刻制造技术（由Loncar集团首创），允许实现散装金刚石衬底中的功能器件，以及工业合作伙伴提供的最先进的材料和材料专业知识（元素6）。B）技术摘要：所提出的实验计划的目标是研究单晶金刚石作为NEMS/ NOMS材料的潜力。该计划将解决许多与晶体NEMS有关的基本问题，包括材料合成，纳米纤维，性能极限等。特别是，将探讨在金刚石中实现高f*Q乘积机械振荡器及其在精密测量（质量，力）中的应用潜力，并作为稳定的定时参考。这将使用成角度蚀刻技术来实现在单晶金刚石衬底中的悬臂梁、轮廓谐振器、声波回音壁模式谐振器和光机械晶体（光子-声子晶格）。最近由哈佛团队展示的倾斜蚀刻技术是基于自上而下蚀刻的组合，其中RIE室中的离子垂直撞击金刚石表面，随后倾斜蚀刻，其中离子以一定角度定向在蚀刻特征上。在后面的蚀刻步骤中，将样品插入法拉第笼中，法拉第笼的几何形状限定了离子在蚀刻衬底上的入射角。学术研究实验室和工业合作伙伴之间的合作是互利的：工业合作伙伴（元素六）将提供最先进的金刚石基板，散装金刚石加工（包括抛光和退火），并在适当时支持商业开发;另一方面，哈佛团队将提供前沿NEMS和NOMS研究的见解，并开发新的纳米纤维和工业上感兴趣的表征技术。该计划具有强大的理论和实验组成部分，解决了纳米力学和光学的基础和工程方面，并为本科生，研究生和研究生提供了独特的研究和教育机会。与工业合作伙伴的合作将为学生提供实习机会。该团队将继续在当地学校和科学博物馆（波士顿）举办公开讲座，并指导对科学和技术感兴趣的高中生。

'1. Proposal Title: GOALI: Stable Nanomechanical Oscillators with Large f*Q Product2. Brief description of project Goals: Nanoscale electro-opto-mechanical systems will be fabricated in diamond, and their applications in precision measurements (e.g. mass, force) will be explored. 3. Abstract: a) Nontechnical Abstract:Diamond is a fascinating material with many remarkable properties. In fact, in many ways it is the ultimate engineering material - the engineer's best friend! For example, diamond has high mechanical hardness and is one of the best thermal conductors. It is optically transparent from the ultra-violet to far infra-red and has a high refractive index (n = 2.4). Finally, it is biocompatible and chemically inert. These properties make diamond a highly desirable material for many applications, including those in life sciences, oil discovery, and industrial sensing. Many of these applications require realization of high-frequency (f), high quality factor (Q), stable, nanoscale electro-mechanical and opto-mechanical systems (NEMS and NOMS). These systems could lead to realization of stable oscillators and sensitive mass measurements, and could operate in both harsh environments (due to diamond's chemical inertness) and in bio-medical setting (due to diamond's bio-compatibility). Despite its unique properties, however, single-crystal diamond has not found many applications in NEMS and NOMS yet! Why? All NEMS/ NOMS platforms have an important feature in common: they consist of a device layer typically a thin film supported by a substrate of a different material that can be sacrificially removed. Single-crystal diamond is one example from an extensive list of materials many with attractive material properties for which such thin film platform does not exist. To overcome this obstacle, the team will leverage angled-etching fabrication technique (pioneered by Loncar group) that allows for realization of functional devices in bulk diamond substrates, and state of the art materials and material expertise provided by industrial partner (Element 6).b) Technical Abstract:The goal of the proposed experimental program is to investigate the potential of single crystal diamond as a NEMS/ NOMS material. The program will address many fundamental questions that pertain to crystalline NEMS, including material synthesis, nanofabrication, performance limits, and so on. In particular, potential for realization of high f*Q product mechanical oscillators in diamond and their applications in precision measurements (mass, force) and as a stable timing reference will be explored. This will be accomplished using angled-etching technique to realize cantilevers, contour resonators, acoustic-wave whispering gallery mode resonators, and optomechanical crystals (photonic-phononic lattices) in single crystal diamond substrates. Angled-etching technique, recently demonstrated by Harvard team, is based on a combination of top-down etching, where ions in the RIE chamber impinge vertically on the diamond surface, with subsequent angled etching, where ions are directed at an angle on the etched features. In the later etch step, the sample is inserted in a Faraday cage, whose geometry defines the angle of incidence of ions on the etched substrate. Collaboration between academic research lab and industrial partner is mutually beneficial: industrial partner (Element Six) will provide state-of-the-art diamond substrates, bulk diamond processing (including polishing and annealing), and when appropriate support commercial development; on the other hand, Harvard team will provide insight into cutting edge NEMS and NOMS research, and develop novel nanofabrication and characterization techniques of interest to industry. The program has strong theoretical and experimental component, addresses both fundamental and engineering aspects of nanoscale mechanics and optics, and represents a unique research and educational opportunity for undergraduate, graduate and post-graduate students. Collaboration with industrial partner will enable internship opportunities for students. The team will continue giving public lectures at local schools and Museum of Science (Boston), and mentoring high school students interested in science and technology.