【作者】 黄玉波；

【导师】 胡小唐；

【作者基本信息】 天津大学 ， 测试计量技术及仪器， 2008， 博士

【摘要】 MEMS力学特性测试及可靠性分析在MEMS的研发和产业化过程中具有极为重要的意义,而力学特性测试又是进行可靠性分析的基础。本论文在调研和分析了MEMS力学特性测试技术及可靠性测试技术研究现状的基础上,对应用相移显微干涉法测试分析MEMS力学特性参数以及在所得参数的基础上对微结构在振动和冲击环境下的可靠性展开研究,主要完成了以下几个方面的工作:1、从方法的类别、应用领域、研究现状和发展趋势等方面系统地调研了MEMS力学特性测试技术及可靠性分析技术的概况,分析和讨论了MEMS力学特性测试及可靠性分析的重要性。2、针对相移显微干涉技术在微结构表面轮廓测量中传统相位解包裹方法的局限性,提出了一种基于模板的广度优先搜索解包裹算法,在相位解包裹的过程中,以由三种不同方法获得的模板图像作为参考,绕过标记出来的非相容区域进行相位展开,从而得到连续而准确的被测表面轮廓。3、针对相移显微干涉法在微结构表面轮廓测量中存在的倾斜误差,提出了一种基于最小二乘法确定调平基准面及坐标旋转重构表面轮廓信息的方法调平被测表面,获得其相对于基准面的表面高度,从而实现了倾斜误差的补偿。4、提出了一种基于相移显微干涉法测量表面轮廓及有限差分法建模的MEMS力学特性分析方法,以未加载电压的微悬臂梁及施加了静电载荷的微悬臂梁作为测试对象,应用相移显微干涉法测量微悬臂梁的表面弯曲量,并应用有限差分法建模解析弯曲量与力学特性值之间的关系,将弯曲量的测量值与模拟值进行比较来提取特性参数值,实现了对微薄膜杨氏模量及残余应力梯度的测量。5、在所测得的力学特性参数的基础上,应用有限元分析软件对表面微加工工艺制备的碳化硅微悬臂梁在振动和冲击载荷下的响应与载荷信号的振幅、频率以及作用时间等参数之间的关系及变化规律进行了仿真分析,并用碳化硅微悬臂梁阵列作为测试样品,以标准的振动试验系统和冲击试验系统为实验平台,设计了一系列振动实验和冲击实验,从微悬臂梁在特定振动和冲击载荷下的失效情况分析了结构的抗振动和抗冲击能力。更多还原

【Abstract】 MEMS mechanical property test and reliability analysis are significant in the research and development and even the industrialization of MEMS, and mechanical property test is the basis of reliability analysis. According to the detailed investigation on current research status of MEMS mechanical property test and reliability analysis techniques, phase-stepping microscopic interferometry is applied to characterize MEMS mechanical properties, based on which reliability of micro structures in vibration and shock environment is studied. The research work of the dissertation mainly includes the following aspects:1. The importance and the general situation of MEMS mechanical property test and reliability analysis are systematically investigated and analyzed, including classification of techniques, application fields, current status and development trend.2. To solve the problem that ordinary phase unwrapping methods in interferometry are not competent in measurement of surfaces with complicated profile or/and nonideal data areas, a breadth-first search phase unwrapping algorithm based on mask is presented. Inconsistent areas are flagged in mask images obtained using three optional methods and then ignored in phase unwrapping process to get continuous and correct surface profile information.3. In order to eliminate tilt errors in surface profile measurement of micro structures using microscopic interferometry, a robust approach based on least square method and coordinate conversion is proposed to compensate tilt errors, which is implemented by finding a reference plane with least squares fit and rotating the coordinate system to get the height information relative to the reference plane.4. A measurement technique to test MEMS mechanical properties based on phase-stepping microscopic interferometry and finite difference method is presented to extract Young’s modulus and residual stress gradient of micro membrane. Unloaded micro cantilevers and cantilevers loaded with DC voltage are used as devices under test, of which surface deflection is measured by phase-stepping microscopic interferometry, and then the relationship between beam deflection and mechanical property parameters is analyzed using finite difference method. Property parameters are then acquired via comparing the measured and modeled deflection data and finding the best fitted values.5. Based on the test results of mechanical property parameters, the relationships and the variation regularities between micromachined SiC cantilevers’ response to vibration and shock signals and amplitude, frequency and duration of shock pulse are analyzed with finite element analysis software. Using SiC cantilever arrays as test samples and standard vibration and shock testing systems as testing platform, a series of vibration and shock experiments are designed and performed to get the resistance capability of the cantilevers to vibration and shock from their failure situations under specific vibration and shock load.更多还原