Investigating the Potentials of A MEMS-based Sensory Platform Health Monitoring of Critical Systems

硅中的压阻性（PR）的应用吸引了许多研究人员开发不同类型的传感机制来测量物理现象，如变形、应力、力和/或加速度。具体而言，微纳米机电系统（MEMS/NEMS） PR已被用于开发用于采矿，石油和天然气，航空航天，民用，电子封装，生物力学，水流和复合材料的外力和内应力和应变传感器。应力监测和分析被认为是工程的一个独特分支，它决定和提高结构和机器的机械强度。通过实验应力分析，可以在不知道在这些条件下作用在零件上的外力的情况下知道机械部件在实际运行中的应力分布，这是对解析和数值方法的重大改进；对于结构健康监测（SHM）至关重要，涉及潜在损伤检测以及关键老化结构的状态维护和故障预防的后续阶段。监测应力应变水平和内力被认为是疲劳强度分析的关键性能参数。大多数可用的应变和力传感器是单向的，通常与其他传感器相结合，以允许二维（平面内）测量；导致更大的占地面积和低规格因素。使用典型的传感技术实现三维（3D）应变或力传感需要更大的足迹，这在仪器仪表方面具有重大挑战。该方案建立在我们目前的突破基础上，实现了能够在3D中感知完整应力图像的10元素PR玫瑰花。这个基于MEMS的概念是基于操纵n-Si（11 11）计划上的掺杂浓度来实现一系列线性独立方程，这些方程能够检测施加在传感器芯片上的面内和面外法向和剪切应力；具有配备温度补偿的潜力，可以在恶劣的环境条件下精确操作。本文改进了三维应力花环的制作方法，提高了非平面法向应力的灵敏度，提高了应力其他方向的信噪比。这将使玫瑰结进一步用作骨干基板，以改进我们团队的另一项技术，即3D负载传感器平台，该技术具有用于各种触觉和消费电子应用的潜力。在构建我们的3D应力和负载传感器平台时，使用基于高规格因数MEMS的PR，使其成为提高灵敏度水平的最佳方法，同时使用更少的能量来运行；这是许多遥感无线系统和消费电子应用的需要，如智能触摸屏和手机。

The utilization of piezoresistivity (PR) in silicon has attracted many researchers to develop different types of sensing mechanisms for measuring physical phenomena such as deformation, stress, force and/or acceleration. Specifically, Micro and Nano Electro-mechanical Systems (MEMS/NEMS) PR has been utilized to develop external force and internal stress and strain sensors for applications in mining, oil and gas, aerospace, civil, electronic packaging, bio-mechanics, water flow and composite materials. Stress monitoring and analysis is considered a unique branch of engineering, which determines and improves the mechanical strength of structures and machines. With experimental stress analysis it is possible to know the stress distribution in a machine component in actual operation without knowing the applied forces acting on the part under these conditions, which is major improvement over analytical and numerical methods; and is essential for Structural Health Monitoring (SHM) involving potential damage detection and the following phases of condition-based maintenance and failure prevention of critical aging structures. Monitoring stresses and strains levels and internal forces are considered key performance parameters for the analysis of fatigue strength. Most available strain and force sensory are single direction and usually is combined with other sensors to allow for 2D (in-plane) measurements; resulting in a bigger footprint with low gauge factor. Achieving a three-dimensional (3D) strain or force sensing with typical sensory techniques requires even larger foot print with significant challenges in instrumentation. This proposal builds on our current breakthrough in achieving a 10-Element PR rosette capable of sensing the full stress picture in 3D. This MEMS based concept is based on manipulating the doping concentration over n-Si (1 1 1) plan to achieve a list of linear independent equation capable of detecting the in-plane and out of plane normal and shear stresses applied on the sensor chip; with the potential to be equipped with temperature compensation to operate accurately in tough environmental conditions. This proposal improves the fabrication of the 3D stress rosette to achieve higher sensitivity in out of plan normal stress and to enhance the signal to noise ratio achieved in other directions of the stresses. This will allow for the rosette to be used further as the backbone substrate to improve another technology of our team, a 3D load sensor platform, which has the potential to be used in various tactile and consumer electronics applications. The use of high gauge factor MEMS--based PR in building our 3D stress and load sensory platforms allow it to be optimum approach to increase its sensitivity level while using less energy to operate; which is a need in many remote sensing wireless systems and consumer electronics applications, such as smart touch screen and phones.