A New Method to Make Programmable Transducers in Microelectromechanical Systems (P-MEMS)

现代技术已经从微机电系统（MEMS）中开发的集成传感器中受益匪浅。磁性微器件是一类MEMS，在微机器人，微流体，芯片实验室等未来的应用中表现出显着的潜力。例如，磁性微流体芯片可以大大降低成本，提高DNA测序的基因组探索和单细胞阵列分析癌症诊断的吞吐量。然而，尽管它们具有巨大的潜力，但磁性材料在微制造过程中的集成仍然是昂贵的，时间效率低的，因此仍然是一个开放的研究课题。例如，通过蚀刻沉积层制造的微换能器具有比相同尺寸的块体磁体更低的性能。不幸的是，即使是最有前途的集成磁性材料的解决方案，在微加工过程中，提供相同的磁性能为整个一组芯片上的微型器件，不能单独调整后。本项目将开发一个全面的解决方案，这些问题。它将在三个工作包（WP）中交付。在WP 1中，该项目将开发一种新的微加工工艺，以实现MEMS（p-MEMS）中的片上可编程传感器。这个过程将集成一个阵列的磁性微器件与个人的MEMS微加热器。在这种创新技术中，每个微型器件的温度响应于对其相应加热器施加的电功率而增加。然后施加外部磁场产生选择性磁性退火。因此，将芯片上的整个磁性微器件暴露于外部磁场并将选定的加热器连接到电源将仅在选定的微器件中导致永磁变化。因此，该技术可以通过施加外部磁场和所选加热器的不同组合来在单个芯片上形成各种磁极性图案。WP 1将与BAE系统公司的专家密切合作，他们对未来的微米和纳米技术特别感兴趣。在WP 2中，这项研究工作将开发一个新的综合微磁学模型（M-MAG），以了解这些微换能器的磁行为。MEMS中厚微加工铁磁（FM）层的磁行为不同于薄膜和块体磁体。厚层由于其在沉积后的原子有序性而不同于块状磁体。它们也不同于薄沉积层，薄沉积层的几个原子的厚度施加了某些约束和假设，这些约束和假设对于厚层不一定有效。新的M-MAG模型将用于开发一种计算机辅助设计（CAD）工具，用于将微器件的磁行为集成到现有的三维微机械建模工具中。这将为未来p-MEMS微换能器的设计提供多物理场有限元分析。在WP 3中，将使用p-MEMS工艺开发原型微流体芯片，以测试和验证该工艺的可靠性以及新CAD工具中M-MAG模型和模拟的准确性。p-MEMS有着广泛的应用。专注于微流体应用将扩展所提出的技术的跨学科优势，超越工程和物理。正如可编程电子集成电路使更广泛的非专业用户社区，拟议的p-MEMS研究将导致这些传感器在生物技术和化学等其他学科中的更广泛使用。因此，WP 3将应用来自各种最终用户的反馈，包括来自iGenomix UK的专家。p-MEMS设计工具包包括层厚度、材料特性和布局设计规则以及M-MAG模型和CAD工具都将在项目网站上免费提供

Modern technologies have vastly benefitted from the miniaturised transducers developed in Micro-Electromechanical Systems (MEMS). Magnetic microdevices are one class of MEMS that demonstrate a significant potential for future applications in microrobotics, microfluidics, lab-on-chip, etc. For example, magnetic microfluidic chips can drastically reduce the costs and increase the throughput of DNA sequencing in genomic explorations and single-cell array analysis for cancer diagnosis. However, despite their great potential, the integration of magnetic material in microfabrication processes remains costly, time-inefficient and is therefore still an open research topic. For example, microtransducers manufactured by etching deposited layers have lower performance than bulk magnets of the same size. Even the most promising solutions for integrated magnetic materials in microfabrication processes, unfortunately deliver identical magnetic properties for the entire set of microdevices on a chip and cannot be individually tuned afterwards.This project will develop a comprehensive solution to these problems. It will be delivered in three work packages (WP). In WP1, this project will develop a new microfabrication process to realise on-chip programmable transducers in MEMS (p-MEMS). This process will integrate an array of magnetic microdevices with individual electrothermal microheaters. In this innovative technique the temperature of each microdevice increases in response to the applied electrical power to its corresponding heater. Applying an external magnetic field then produces the selective magnetic annealing. Therefore, exposing the entire magnetic microdevices on a chip to an external magnetic field and connecting selected heaters to electrical power will result in permanent magnetic changes only in the selected microdevices. Hence, this technique can develop various magnetic polarity patterns on a single chip by applying different combinations of external magnetic fields and selected heaters. WP1 will be carried out in close partnership with experts from BAE Systems who are particularly interested in the future micro and nano technologies. In WP2, this research work will develop a new comprehensive micromagnetism model (M-MAG) to understand the magnetic behaviour of these microtransducers. The magnetic behaviour of thick microfabricated ferromagnetic (FM) layers in MEMS is different from thin films and bulk magnets. Thick layers are different from bulk magnets due to their atomic ordering after deposition. They are also different from thin deposited layers whose thicknesses of a few atoms impose certain constraints and assumptions that are not necessarily valid for thick layers. The new M-MAG model will be used to develop a computer aided design (CAD) tool for integrating the magnetic behaviour of microdevices into the available three dimensional micromechanical modelling tools. This will provide the multiphysics finite element analysis for the design of future microtransducers in p-MEMS. In WP3, a prototype microfluidic chip will be developed using the p-MEMS process to test and verify the reliability of the process as well as the accuracy of the M-MAG model and simulations in the new CAD tool. There is a wide variety of applications for p-MEMS. Focusing on microfluidic applications will extend the cross disciplinary benefits of the proposed technique beyond Engineering and Physics. Just as programmable electronic integrated circuits enabled a wider community of non-expert users, the proposed research on p-MEMS will lead to a broader usage of these transducers emerging among other disciplines such as Biotechnology and Chemistry. Hence, WP3 will apply feedback from various end-users including experts from iGenomix UK. The p-MEMS design kit including the layer thicknesses, material properties and layout design rules as well as the M-MAG model and the CAD tool will all be made freely available on the project webs