EAGER: Ultra-Sensitive Resonant MEMS Magnetometers with Internal Thermal-Piezoresistive Amplification

EAGER：具有内部热压阻放大功能的超灵敏谐振 MEMS 磁力计

• 批准号: 1345161
• 负责人: Siavash Pourkamali Anaraki
• 金额: $ 15.06万
• 依托单位: University of Texas at Dallas
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-10-01 至 2015-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1345161&HistoricalAwards=false
• 关键词: EAGER; Ultra; Sensitive; Resonant; MEMS

Objective: The objective of this project is to explore the potentials of the internal thermal piezoresistive quality factor and displacement amplification effect in silicon resonant microstructures for realization of ultra-high sensitivity and low noise magnetometers. MEMS magnetometers consisting of silicon based resonant microstructures with integrated insulated metallic traces will be designed and fabricated. The performance of the fabricated devices will be characterized and the effect of internal amplification offered by the strategically designed silicon structure on sensitivity and noise level of the magnetometers will be investigated. Intellectual Merit: The proposed MEMS magnetometers operate based on harvesting and internally amplifying the Lorentz force (force applied to a current carrying conductor in a magnetic field). Extremely high effective quality factors (Q) up to ~1000X larger than the intrinsic mechanical Q of the resonator have been demonstrated using the internal thermal-piezoresistive amplification effect. It is expected that such high Q values can amplify vibration amplitude resulting from the Lorentz force without adding to the electronic noise level leading to superior performance for the proposed sensors. Preliminary analysis show that noise levels in the pT/Hz1/2 range should be within reach, which is comparable to that offered by some of the most sophisticated technologies available. The proposed effort combines the simplicity, small size, and ease/low cost of fabrication of silicon-based MEMS magnetometers with unprecedentedly high sensitivities. The potential outcome will be small size, low cost and easy to use ultra-sensitive magnetometers that circumvent shortcomings of other existing technologies such as the need for cryogenic cooling, integration of exotic materials, large size and high power consumption. Broader Impact: Highly sensitive, small size, and easy to use magnetometers can have transformative effects in various areas including biology and biomedical engineering, geology and mineral/oil exploration, as well as surveillance and defense (through wall/underground imaging and target tracking). For example, arrays of SQUIDs requiring cryogenic cooling are currently used for mapping brain activity by monitoring small magnetic fields (tens to thousands of femotTesla) resulting from firing of neurons in the brain. Small size and convenience offered by the proposed microscale devices can leads to significant advances in brain mapping and enable development of advanced portable brain monitoring devices. On the educational front, one postdoctoral researcher, one PhD level graduate student and up to two undergraduate researchers will be trained and directly involved in the research activities. Results from the research activities will serve as interesting course materials enriching the PIs ongoing courses in MEMS and microsystems. The experience gained by the PI during the course of this project will provide him with a highly valuable insight in a new field of research that will be transferred to current and future students.

目的：该项目的目的是探索硅共振微观结构中内部热压电质量因子和位移放大效应的潜力，以实现超高灵敏度和低噪声磁力计。将设计和制造由具有集成绝缘金属痕迹的基于硅的共振微结构组成的MEMS磁力计。将研究制造设备的性能，并将研究战略设计的硅结构对磁力计的灵敏度和噪声水平提供的内部扩增的影响。智力优点：拟议的MEMS磁力仪基于收获和内部扩增Lorentz力（将力应用于磁场中的电流携带导体）。使用内部热 - 质质抗化效果证明了比谐振器的内在机械Q大的极高有效质量因子（Q）。可以预期，如此高的Q值会扩大洛伦兹力引起的振动幅度，而不会增加电子噪声水平，从而导致提出的传感器的性能出色。初步分析表明，PT/HZ1/2范围中的噪声水平应在触及范围内，这与一些最复杂的技术提供的噪声水平相当。提出的努力结合了基于硅的磁力计的简单性，尺寸小，易于/低成本，具有前所未有的高灵敏度。潜在的结果将是尺寸很小，成本较小和易于使用的超敏感磁力计，以避免其他现有技术的缺点，例如需要低温冷却，外来材料的整合，大尺寸和高功率消耗。更广泛的影响：高度敏感，尺寸且易于使用的磁力计在包括生物学和生物医学工程，地质和矿产/石油探索以及监视和防御（通过墙/地下成像和目标跟踪）在内的各个领域都具有变革性效应。例如，目前使用需要低温冷却的鱿鱼阵列来绘制大脑活动，通过监测小型磁场（数十至成千上万的femottesla），这是由于大脑中神经元的发射而导致的。拟议的显微镜设备提供的小尺寸和便利性可导致大脑映射的重大进展，并能够开发高级便携式大脑监测设备。在教育方面，一名博士后研究员，一名博士学位研究生和多达两名本科研究人员将接受培训并直接参与研究活动。研究活动的结果将作为有趣的课程材料，丰富了MEM和微系统中PIS正在进行的课程。 PI在该项目过程中获得的经验将为他提供一个新的研究领域的高度宝贵见解，并将转移到当前和未来的学生中。