Numerical Investigation of Micromachined Structures for Thin Layers

In the present paper we analyze numerically the high-frequency behavior of different micromachined structures including MEMS. One special feature of micromachined structures is the presence of very thin layers - compared to other geometrical dimensions, resulting from the technological process. With usual numerical methods, where the entire domain is discretized, those thin layers are difficult to consider. The alternatives are a very small mesh size with the resulting extreme long calculation times and large storage requirements or approximate boundary conditions, which are usually less accurate. Here it will be shown how thin-layer structures can be analyzed very accurately with reasonable numerical effort by the Transmission Line Matrix method (TLM) and by the Method of Lines (MoL). The numerical methods will be presented, especially the means which are necessary to avoid long calculation times and which make these methods useful for an efficient design of the proposed structures. The obtained numerical results for the scattering parameters are compared with measurements in order to judge their accuracy.