Dr. Boris Svilicic, Professor, Faculty of Maritime Studies, University of Rijeka, Croatia

Title: Silicon Carbide Electrothermally Tunable MEMS Resonators

Abstract: Micro-electro-mechanical system (MEMS) resonators have been extensively studied as a potential candidate technology for realization of a variety of devices including oscillators, filters, gyroscopes, accelerometers and sensors. While silicon is the most utilized resonator structural material due to its associated well-established fabrication processes, cubic silicon carbide (3C-SiC) is an excellent candidate for use as a structural material when operation in harsh environments is required, due to its robustness, chemical inertness and high temperature stability. However, one of the main challenges for practical implementations of MEMS resonators is voltage controlled resonant frequency adjustment to overcome fabrication tolerances and reliability issues. Electrothermal actuation is an emerging transduction technique that brings advantages such as simple fabrication process, low actuation voltages, impedance matching and wide frequency tuning range that can be obtained by applying low DC bias voltages. Silicon carbide MEMS resonators that are actuated and tuned electrothermally have been fabricated with three different resonant structures: single-clamped beam, double-clamped beam and diaphragm. Electrical characterization of the devices has been performed by measuring the two-port transmission frequency response. The devices' design, materials, fabrication process and measurement setup details will be presented.

Keywords: silicon carbide, MEMS, resonators, electrothermal actuation, piezoelectric sensing