微结构力学特性分析

Analysis of Mechanical Properties of Microstructure

在MEMS器件中,用的较多的构件有薄膜材料,对其力学性能的分析是MEMS器件分析的关键所在.由于受到残余应力,弹性模量的误差,薄膜晶格的各向异性,泊松比,微结构的疲劳和破坏韧性等的影响,实际测量数据和理论公式总存在一些误差.本文通过实际测量的数据在Matlab环境下的分析,得到如下结论:当微结构梁的挠度小于600μm时,力与挠度的关系理论公式与实际数据对比是比较一致的,大于600μm的实验数据渐渐地偏离理论上的直线公式,呈现出非线性的特性.

Membranous material is usually used in MEMS components, so analyzing its mechanical properties is important. Due to the influences such as residual stress, elasticity modulus error, the crystal lattice anisotropic of thin film, the Poisson＇s ratio, fatigue and toughness destruction of the microstructures and so on, the error inevitably exists between the actual tested data and the theoretical value. This article analyzes the actual tested data by Matlab, and it is found that： when the deflection of microstructure beam is less than 600 μm, the theoretical formula about force and deflection is consistent with the experimental data; when the deflection of the microstructure beam is more than 600 μm, experimental data gradually deviate from the theo- retical straight line and present the nonlinear properties.