Microstructured Carbon/SiCX (X=O, N)-Based High Temperature Strain Gauge

该项目旨在开发适用于高温(T&>；400℃)的微型应变计，以解决基础研究和应用相关研究。该项目主要致力于研究碳含量为13%~20%的C/SiCX(X=O，N)纳米复合薄膜的压阻效应，以及实现比目前最先进的硅基压阻传感器更好的高温稳定传感器结构。将实现厚度约1µm的C/SiCX薄膜的合成和表征，并将其集成到实验室传感器测试结构中。旋涂C/SiCX薄膜的硅悬臂梁将被用作压阻式传感器元件。它们的性能将使用三点弯曲测试装置进行评估，该装置将为此特定目的而设计和建造。为了能够对C/SiCX基陶瓷薄膜的电阻进行四点测量，将开发和表征高温稳定连接。此外，还将研究单个测量元件之间的串扰，因为它们被放置在非结构化高阻抗C/SiCX层的顶部。弯曲测试将在室温至800°C的温度范围内进行，包括测量拉应力和压应力的量规系数。传感器元件的测试将与结构特征相结合，例如机械应力下的裂纹形成及其在腐蚀性大气中关于成分和厚度的演化。在接下来的项目中，硅悬臂梁实验的结果可以转移到具有压阻C/SiCX层的背面刻蚀硅膜传感器的实际应用中。

The project aims to develop micro-sized strain gauges applicable at elevated temperatures (T > 400 °C) addressing both basic and application-related research. The project is mainly focused on the investigation of the piezoresistive effect of C/SiCX (X = O, N) nanocomposite thin layers with 13 to 20 vol% carbon as well as enabling the realization of high-temperature stable sensor structures superior to the state-of-the-art piezoresistive sensors based on silicon. The synthesis and characterization of C/SiCX thin films with a thickness of ~1 µm and their integration in a laboratory sensor test structure will be realized. Silicon cantilevers, spin-coated with C/SiCX thin films, will be used as piezoresistive sensor elements. Their performance will be assessed using a 3-point bending test setup, which will be designed and built for this specific purpose. To enable 4-point measurements of the resistance of the C/SiCX-based ceramic film, high temperature stable connections will be developed and characterized. Furthermore, the crosstalk between the single measurement elements will be investigated, as they are placed on top of an unstructured high impedance piezoresistive C/SiCX layer. The bending tests, including measurements of the gauge factor for both tensile as well as compressive stress, will be performed in a temperature range spanning from room temperature up to 800°C. The tests of the sensor elements will be combined with structural characterization e.g. crack formation under mechanical stress and its evolution concerning composition and thickness in corrosive atmospheres. In a subsequent project, the results from the silicon cantilever experiments can be transferred to the actual application of a backside etched silicon membrane sensor with the piezoresistive C/SiCX layer.