Statistical Modeling and Contact Analysis of Fractal Topography for Radio-Frequency (RF)-MEMS

该奖项的研究目标是开发用于RF-MEMS（射频MEMS）接触分析的多尺度分形形貌模型，以提高其设计和制造的可靠性。配合面形貌和接触力学决定了RF-MEMS的性能质量。地形是一个随机场，具有尺度相关的规则和自仿射分形信号特征，范围从1nm到100ìm。在该奖项中，将开发一种新颖且广泛适用的方法，用于表征和建模多尺度分形地形，然后将其纳入RF-MEMS性能和可靠性改进的接触分析。四个关键的研究目标是：开发一种严格的统计方法，用于微/纳米地形采集、表征和建模，以面对多尺度、分形和随机表面结构；2)建立了与真实地形具有较高保真度和相关性的统计规则分形地形模型；3)创建考虑弹塑性变形、多尺度分层粗糙度和统计地形的微/纳米接触模拟；4)从地形、接触模拟和实验研究的相关性中获得关于破坏机制的新知识。这项研究的成功完成将为微机电系统的表面形貌及其相关接触力学提供一个新的模型。新的计算基础设施的创建将产生相当大的影响。该研究结果可直接用于MEMS行业，用于测量、表征和量化MEMS开关中电荷和表面磨损随时间的分布和演变，以及研究表面的一致性和可变性，从而提高设计和制造水平。该奖项的结果将通过专业学术和工业合作网络、期刊出版物和会议广泛传播。未被充分代表的研究生和本科生将参与这项研究，并将获得有价值的信息提取、统计建模和数据采集中使用的计量技术的挑战。该研究的部分成果将被整合到本科和研究生课程中，使该校所有工程系的学生受益。这项研究的结果也将通过新生暑期学院（FSI）项目分享给即将入学的新生。

The research objective of this award is to develop a multi-scale fractal topography model for contact analysis in RF-MEMS (Radio Frequency MEMS) to improve the reliability in its design and manufacturing. Topography of mating surfaces and contact mechanics determines the performance quality of RF-MEMS. Topography is a random field and has scale-dependent regular and self-affine fractal signal features over several orders of magnitude, ranging from 1nm to 100ìm. In this award, a novel and widely-applicable methodology for characterizing and modeling multi-scale fractal topography will be developed that will then be incorporated into contact analysis for RF-MEMS performance and reliability improvement. The four key research objectives are: the development of a rigorous statistical methodology for micro/nano topography acquisition, characterization, and modeling in the face of multi-scale, fractal, and random surface structures; 2) development of a statistical regular-fractal topography model that has a high fidelity and correlation to real topography; 3) creation of a micro/nano-contact simulation that takes into account elasto-plastic deformation, multi-scale hierarchical asperity, and statistical topography; and 4) generation of new knowledge on failure mechanisms obtained from the correlation among topography, contact simulation, and experimental study.Successful completion of this research would lead to a new model for surface topography and its associated contact mechanics for use in micro-electro-mechanical systems. The creation of a new computational infrastructure will be quite impactful. The results of the study can be used directly in MEMS industries for measuring, characterizing, and quantifying the distribution and evolution of charge and wear of surfaces in MEMS switches over time and for studying consistency and variability of surfaces, enhancing both design and manufacturing. The results of this award will disseminated widely via professional academic and industrial collaborative networks, journal publications, and conferences. Under-represented graduate and undergraduate students will participate in this research and will receive valuable exposure to the challenges of information extraction, statistical modeling and metrological techniques used in data acquisition. Some of the results from the research will be integrated into undergraduate and graduate courses, benefiting all the engineering students at the university. The results of this study will also be shared to incoming freshmen through the Freshmen Summer Institute (FSI) program.