TCAD for MEMS
R. Paganini*, R. Ruehl*, J. Funk and H. Baltes Physical Electronics Laboratory, ETH Zurich, Switzerland +Integrated Systems Laboratory, ETH Zurich, Switzerland *ISE AG, Switzerland Introduction. We present key components of a technology CAD (TCAD) tool for inte¬ grated micro electro mechanical system (iMEMS) simulation. The TCAD capabilities augment the SOLIDIS device simulator [1], Key components are: Meshing interface to process simulation; Application-oriented solid modeler; Algorithms for iMEMS sensor and actuator device simulation using finite and boundary element compuational engines; Interface for mixed-signal system level simulation using SPICE. Meshing. We present an approach to boundary-to-mesh generation based on a Monte
Enhanced multipole acceleration technique for the solution of large Poisson computations
The solution of Poisson's simulations in large, geometrically complex domains with various boundary conditions are of interest in many physical computations. In this paper, we focus on electrostatic analysis. This is important for microactuator (MEMS) and interconnect modeling and also in the simulation of the electrostatic properties in VLSI chips, such as CCD sensors and DRAM cells. The computation of the static electric potential and field distribution involves the solution of the Poisson's equation, or in case of charge free space, Laplace's equation. The boundary element method has proven to be well suited for the solution of these partial differential equations in both 2- and 3-D. The required computational resources can be significantly reduced with the use of multipole acceleration techniques. An enhanced multipole (MP) acceleration technique is presented, allowing for reduced computational time and memory requirements in all stages of the computational process: the assembly of the global system of equations, the solution of the system and the evaluation of the potential and flux at specified internal positions. Contrary to previous applications of MP acceleration to Poisson's equation, the method allows the treatment of a wider class of boundary conditions, including Neumann and floating. The method is applicable both in two and three dimensions using a constant or high order boundary elements.
Thermally actuated CMOS micromirrors
Thermally actuated micromirrors fabricated using a standard CMOS process and one subsequent anisotropic silicon etch step are presented. The device consists of a mirror plate supported by bimorph cantilever beams. Even short beams show a large deflection effect. A theoretical analysis valid for n-morph bending beams has been derived and found to be consistent with experimental and computer-simulation results.