FEM analysis of microbeam bending experiments using ultra-micro-indentation

Bending experiments of cantilever microbeams in an ultra micro indenter can be used to determine Young's modulus E of micromechanical components. Using the Finite Element Method, it was investigated for anisotropically etched microbeams of monocrystalline silicon, whether elementary beam bending and shearing equations are applicable for the evaluation of the experiments. It was found that the inclination and compliance of the beam support, and the indentation can lead to significant errors in E when the elementary equations are applied. Based on the FEM results, relations are derived that correct the elementary equations for these influences. In the experimental part of this study, Young's modulus E of monocrystalline silicon was determined from the microbeam experiments. The exellent agreement between the experimentally determind value of E with the well known literature value demonstrates the reliability of the microbeam testing technique.