Tuning In-Plane Fixed-Fixed Beam Resonators With Embedded Heater in CMOS Technology

This letter presents CMOS-MEMS fixed-fixed beam resonators with wide active frequency tuning range capability attributed to the axial stress modulation using embedded heaters. Two resonators, consisting of multiple metal, dielectric layers, and poly1 layers, were designed; the first resonator at 303.4 kHz, while the second at 2053 kHz, achieve the frequency tuning ranges of 35.7%-42.6%, respectively. Electrostatic transduction is achieved by embedded metal beams, and used to drive the device into resonance. The heaters, made of poly1, are embedded directly into the resonators during the CMOS process to achieve low power consumption and optimum heating efficiency. A power consumption of 900 μW/beam is achieved for the first design of 152 μm length beam, while providing a frequency tuning of 35.7%.