RF MEMS continuous reversible variable inductor based on a microfluidic network

International audienceIn this work, RF MEMS continuous reversible variable inductor has been fabricated by using microelec-tronic technology and lamination process. We review, evaluate and compare this variable inductor with other work. The proposed inductor is a dual circular coil and has an inductance of few nH. The fundamental idea is to place a liquid droplet between the metal turns of a coil in order to modify the capacitive/resistive coupling between metal tracks and hence to change the stored magnetic energy. The SU-8 resin was used to realize the microfluidic channels and Au as metallic tracks. To prove the reversibility of the inductor, two cases were studied: filling and emptying of channels. The tuning range of the inductance is approximately 107 % at 1.6 GHz, making these devices very suitable as building blocks in many RF applications

Sensing and MEMS Devices in Thin-Film SOI MOS Technology

Silicon-on-Insulator (SOI) technology is emerging as a major contender for heterogeneous microsystems applications. In this work, we demonstrate the advantages of SOI technology for building thin-film field-effect biosensors and optical detectors, physical and chemical sensors on thin dielectric membrane as well as three-dimensional (3D) microelectromechanical (MEMS) sensors and actuators. The flatness and robustness of the thin membrane as well as the self-assembling of 3D microstructures rely on the chemical release of the microstructures and on the control of the residual stresses building up in multilayered structures undergoing a complete thermal process. The deflection of multilayered structures made of both elastic and plastic thin films results from the thermal expansion coefficient mismatches between the layers and from the plastic flow of a metallic layer. The proposed CMOS-compatible fabrication processes were successfully applied to suspended sensors on thin dielectric membranes such as gas-composition, gas-flow and pressure sensors and to 3D self-assembled microstructures such as thermal and flow sensors