Development of SiC-LC Resonant Wireless High Temperature Pressure Sensor

高温压力传感器在航天、航空、国防建设、能源开发等领域有广阔应用需求。传统硅材料在高于200℃后机械/电学性能均受到较大影响，无法满足高温应用要求。另一方面，传统高温传感器引线会导致电源、信号电路的温度升高问题，基于LC谐振的无线传感器能实现非接触式测量，达到电性连接、调理电路与高温热源之间物理隔离，提高传感器工作温度和稳定工作时间。因此，本论文提出一种SiC-LC谐振式无线高温压力传感器，主要研究工作如下： (1)根据LC谐振测量原理设计电感内置及电感外置两种敏感元件的结构方案，采用Silvaco软件对本体电容进行对比分析，得出电感内置结构具有本体电容小、谐振信号易于检测、制备工艺难度更低等...High temperature pressure sensor has broad application requirements in aerospace, aviation, national defense construction, energy development and other fields. Silicon material performance is greatly affected in the higher than 200℃ performance, can not meet the requirements of high temperature applications. At present, high temperature sensor will lead to power supply, signal circuit temperature...学位：工学硕士院系专业：航空航天学院_电气检测技术及仪器学号：1992014115289

Study on Preparation and Reflow Process of Nano Glass Powder for MEMS Encapsulations

封装一直是MEMS器件的重难点，封装的好坏直接决定器件的成败。受成本、方便性、封装性能、工艺复杂程度、器件大小等诸多因素的影响，使用盖帽的圆片级封装成为一种明智、新颖和备受欢迎的方法，是MEMS器件封装的趋势。玻璃盖帽具有寄生电容小、和硅键合容易、绝热性能好等优点，是常用的封装盖帽。特别是高频RF传感器，玻璃盖帽因其良好的电学隔离作用，成为盖帽的最佳选择。然而玻璃盖帽的制作却非常困难。传统玻璃回流工艺是如今较好的一种玻璃盖帽制作方式，但仍然有很多不足，如抛光容易碎片、回流时间长、有最小线宽的限制、需要高真空阳极键合等。 本文以玻璃盖帽为出发点，研究了玻璃粉回流工艺的若干问题。为了获得纳米玻璃...Packaging which directly determines the success or failure of the device has always been the major difficulty in MEMS devices. Effected by many factors such as cost, convenience, package performance, process complexity, device size, wafer level packaging using a cap becomes a wise, novel and popular way, and it is the inevitable trend of MEMS package. Due to the advantages of small parasitic capac...学位：工学硕士院系专业：航空航天学院_机械制造及其自动化学号：1992014115287

Inductively Coupled Passive Resonance Sensors: Readout Methods and Applications

Measurement systems are used to acquire information from the surrounding world. The requirements of the measurement system depend on the application, and the acquired information is used in different ways. For example, measurements are taken as part of the control systems of industrial processes. Alternatively, the information obtained from the measurements can be used to provide answers to scientific questions. Each measurement has a case-specific importance for the user and a certain cost in terms of time and money. Therefore, the same measurement approach is not optimal in every case. The design process of the measurement systems always includes a compromise between performance, viability, and cost. These factors are, in turn, strongly dependent on the implementation of the measurement system in each separate case. Inductively coupled passive resonance sensors provide a measurement method that has two notable benefits: the simple structure of the sensors and the possibility to take short-range wireless measurements. However, the limitations of the available readout devices have often impeded the use and development of these sensors in many demanding applications. In addition, uncertainty in the measurement results due to inductive coupling hinders the use of this method.This work concerns the development and implementation of a measurement system based on inductively coupled passive resonance sensors. A custom-made readout device to improve the feasibility of the readout in applications where continuous field measurements are performed was both specified and produced. The readout device was implemented using a simplified version of the method used in conventional impedance analyzers. In addition, signal processing methods were developed which can extract resonance characteristics from the measured data. A special algorithm was developed to compensate for the effects of the changes in the inductive coupling when the measurement distance varies. The operation of the developed readout methods was studied using simulations, and several realistic measurement configurations were tested. Competing readout methods published in the literature were also simulated. The accuracy of all the studied methods depended on the configuration of the measurement system. The inductive coupling coefficient also had a significant influence on the accuracy of the tested methods.The newly-developed readout methods and the inductively coupled passive resonance sensor were then utilized in a medical application to monitor the pressure between the skin and compression garments. These garments are used, for example, to improve the healing of burns and reduce swelling in the legs. Effective medical treatment of such conditions requires that the appropriate pressure is applied. With this system, the pressure reading under the compression garment can be obtained by using simple disposable sensors that can be read wirelessly through a thin fabric. Using our inductive coupling compensation method, the sensor enabled the monitoring of the pressure with the required level of precision.Inductively coupled resonance sensors can also be used to monitor the properties of the materials around the sensor. This monitoring is possible because the permittivity of the environment near to the sensor affects the sensor’s resonance characteristics. This method was tested in two applications. In the first application, the manufacturing process of ceramic slurry was monitored by a sensor that was installed inside the container where the slurry was mixed. The resonance characteristics of the sensor were measured as the manufacturing process was incrementally carried out. The results indicated that the method could be used to control the composition of the slurry. In the second application, the inductively coupled sensors were tested in monitoring the degradation processes of two different polymers during hydrolysis. In this application, the sensors were encapsulated into the tested polymers. The polymer samples were kept inside containers filled with buffer solution and the resonance characteristics of the encapsulated sensors were then measured wirelessly from outside. The results showed a clear difference in degradation profiles between the tested polymers. The method may provide a novel way to continuously monitor the degradation processes of certain materials.In summary, the developed readout methods improved the applicability of inductive coupled passive resonance sensors in the tested applications and created novel ways to acquire information. This new technology provides a good starting point for the development of a new generation of inductively coupled passive resonance sensors

Design and Manufacturing of a Passive Pressure Sensor Based on LC Resonance

The LC resonator-based passive pressure sensor attracts much attention because it does not need a power source or lead wires between the sensing element and the readout system. This paper presents the design and manufacturing of a passive pressure sensor that contains a variable capacitor and a copper-electroplated planar inductor. The sensor is fabricated using silicon bulk micro-machining, electroplating, and anodic bonding technology. The finite element method is used to model the deflection of the silicon diaphragm and extract the capacitance change corresponding to the applied pressure. Within the measurement range from 5 to 100 kPa, the sensitivity of the sensor is 0.052 MHz/kPa, the linearity is 2.79%, and the hysteresis error is 0.2%. Compared with the sensitivity at 27 °C, the drop of output performance is 3.53% at 140 °C

Design and Manufacturing of a Passive Pressure Sensor Based on LC Resonance

The LC resonator-based passive pressure sensor attracts much attention because it does not need a power source or lead wires between the sensing element and the readout system. This paper presents the design and manufacturing of a passive pressure sensor that contains a variable capacitor and a copper-electroplated planar inductor. The sensor is fabricated using silicon bulk micro-machining, electroplating, and anodic bonding technology. The finite element method is used to model the deflection of the silicon diaphragm and extract the capacitance change corresponding to the applied pressure. Within the measurement range from 5 to 100 kPa, the sensitivity of the sensor is 0.052 MHz/kPa, the linearity is 2.79%, and the hysteresis error is 0.2%. Compared with the sensitivity at 27 °C, the drop of output performance is 3.53% at 140 °C