MEMS COMPONENTS FORMED FROM NANOSTRUCTURAL METALS

等通道转角加工(ECAP)制备的纳米颗粒材料在广泛的应用领域为创新产品提供了新的结构和功能特性。通过使金属和合金在静水压力下进行高度塑性变形，ECAP开辟了从传统微观结构制造纳米级颗粒的途径，而不涉及昂贵、危险的纳米粉末。ECAP的可行性和一系列包层合金的高成形性已经被证明，但到目前为止，它的工业应用仍处于起步阶段。微电子机械系统(MEMS)是一种前景看好但尚未开发的应用。MEMS作为21世纪关键技术的成功与否，取决于与复杂MEMS器件的设计和制造相关的材料问题的解决。材料科学关注的关键领域包括可微制造材料的扩展、可用于微制造结构的工艺的改进以及用于表征和选择用于MEMS应用的材料的方法的改进。利用不断发展的制造工艺和新材料，MEMS将为集成化的微电子机械系统提供小尺寸、低成本和高功能的优势。纳米结构铝对MEMS很有吸引力，因为与竞争材料(硅、二氧化硅、氮化硅、镍)相比，纳米结构铝可以提供更好的机械性能，并具有极好的导电性和热导率。此外，使用所提出的SPD工艺与亚微米尺寸公差相结合，有可能导致非常低成本的大规模生产。该项目旨在进一步加强南安普顿大学工程科学学院实验室的ECAP实验室设施，该设施将被用作生产超细颗粒材料的设施。MEMS元件的模具将通过光刻图形和DRIE来设计和制造，而换热器和微型热管等MEMS元件将通过这些超细颗粒材料的压花来制造。我们将利用仪表化压花试验台，结合电子显微镜和力学模型对加工过程进行研究，以了解影响MEMS元件微结构和性能的微观结构和摩擦学因素。该项目有可能为更传统的行业提供一个门户，通过加工包层铝合金来开发新的MEMS应用，从而促进纳米技术的发展。

Materials with nano-scale sized grains produced by equal channel angular processing (ECAP) offer new structural and functional properties for innovative products in a wide range of applications. By subjecting metals and alloys to a high degree of plastic deformation under hydrostatic pressure, ECAP opens the way to create nano-scaled grains from conventional microstructures, without involving costly, hazardous nano-powders. The feasibility of ECAP, and high formability of a range of ECAPed alloys, has already been demonstrated, but so far its industrial application is still in its infancy. A promising, but as yet unexplored application is for microelectromechanical systems (MEMS). The success of MEMS as a key technology in the twenty-first century depends on the solution of materials issues associated with the design and fabrication of complex MEMS devices. Key areas for materials science to focus on include the extension of the available set of materials that can be microfabricated, the refinement of the set of processes available to microfabricate structures, and improvement of the methods used to characterize and select materials for MEMS applications. Using an ever-expanding set of fabrication processes and new materials, MEMS will provide the advantages of small size, low-cost and high-functionality to integrated microelectromechanical systems. Nano-structured aluminium is attractive for MEMS as it can offer improved mechanical properties compared to competing materials (Si, SiO2, Si3N4, Ni) combined with greatly superior electrical and thermal conductivity. In addition, the use of the proposed SPD processing coupled with sub-micron dimensional tolerances has the potential to result in very low cost mass production. This project is designed to further enhance a lab-scale ECAP facility at the laboratory of the School of Engineering Sciences, University of Southampton, which will be used as the facility to produce ultra-fine grain materials. Dies for MEMS components will be designed and created by lithographic patterning and DRIE, and MEMS components such as heat exchangers and micro heat pipes will be made by embossing from these ultra-fine grain materials. An instrumented embossing rig, together with electron microscopy and mechanics modelling of the process will be investigated to understand the microstructural and tribological factors affecting the microstructures and properties of the MEMS components. This project has the potential to provide a gateway for a more traditional industry to contribute to nanotechnology through processing ECAPed aluminium alloys to develop new MEMS applications.