An improved meshing technique and its application in the analysis of large and complex MEMS systems

This paper presents a new local refining meshing algorithm which is referred to as the Exposed Face Mesh (EFM) algorithm, for three-dimensional coupled electromechanical analysis with multiple dielectrics. This algorithm allows for the independent refinement of the electrostatic mesh and mechanical mesh in a coupled system. This approach is compared to the commonly used volume refining mesh method in which both the electrostatic and mechanical mesh domains are refined concurrently. The new EFM method is shown to have substantial improvement in increasing accuracy of results and reducing computational expense (time and memory) especially for fringe electric field dominated structures. For a typical comb drive structure, the EFM algorithm generates much fewer volume mesh nodes for mechanical analysis (20 times less) and fewer surface mesh panels for electrostatic analysis (10 times less) than the standard volume refining mesh method. At the same time, the EFM method showed an improvement in accuracy from 15% (using the standard mesh) to within 5% for this case. The IntelliCAD(TM) MEMS modeling software has incorporated this Exposed Face Mesh algorithm and made it a unique software system to handle general device structures accurately.