AN INNOVATIVE AUXETIC ELECTRICALLY-TUNABLE MEMS MECHANICAL FILTER

An innovative Micro-Electro-Mechanical System (MEMS) electrically-tunable filter exploiting bandgap and auxetic properties of a mechanical structure is here proposed for the first time to the Authors best knowledge. It embeds a deformable structure made of a periodic repetition of an auxetic unit cell and four sets of push-pull parallel-plates capacitors placed on its sides. Thanks to the bandgap properties of the auxetic structure, the proposed MEMS acts as a mechanical filter in the mega-hertz range. Electrostatic-tunability is achieved through the auxeticity of the implemented unit cell: when a DC bias voltage is applied on tuning electrodes, it induces a tensile force that deforms the structure, thus shifting the bandgap opening frequency range.