In this paper we present our efforts in characterizing and optimizing the influence of a Wafer-Level Packaging (WLP) solution on the electromagnetic behaviour of RF-MEMS devices. To this purpose, a fully parameterized FEM model of a packaged Coplanar Waveguide (CPW) is presented in order to optimize all the technology degrees of freedom (DoF’s) made available by the fabrication process of the capping part. The model is implemented within the Ansoft HFSSTM electromagnetic simulator, after its validation against experimental data. Moreover, a simulation approach of a capped RF-MEMS varactor is shown. It is implemented in the Spectre© simulator within Cadence© environment. The MEMS part is treated by means of a compact model library implemented in VerilogA© language. A lumped elements network accounting for the parasitics surrounding the intrinsic RF-MEMS varactor is extracted from experimental data. Finally, the S-parameters description of the package, obtained by Ansoft HFSSTM simulations, is included in the Spectre© schematic....

The very significant growth of the wireless communication industry has spawned tremendous interest in the development of high performances radio frequencies (RF) components. Micro Electro Mechanical Systems (MEMS) are good candidates to allow reconfigurable RF functions such as filters, oscillators or antennas. This paper will focus on the MEMS electromechanical resonators which show interesting performances to replace SAW filters or quartz reference oscillators, allowing smaller integrated functions with lower power consumption. The resonant frequency depends on the material properties, such as Young's modulus and density, and on the movable mechanical structure dimensions (beam length defined by photolithography). Thus, it is possible to obtain multi frequencies resonators on a wafer. The resonator performance (frequency, quality factor) strongly depends on the environment, like moisture or pressure, which imply the need for a vacuum package. This paper will present first resonator mechanisms and mechanical behaviors followed by state of the art descriptions with applications and specifications overview. Then MEMS resonator developments at STMicroelectronics including FEM analysis, technological developments and characterization are detailed....