A CMOS-MEMS Ultrasensitive Thermometer Using Internal Resonance Iuduced Frequency Combs
Journal
Proceedings of the IEEE International Conference on Micro Electro Mechanical Systems (MEMS)
Journal Volume
2023-January
ISBN
9781665493086
Date Issued
2023-01-01
Author(s)
Abstract
This work demonstrates a CMOS-MEMS resonant thermometer with a temperature coefficient of frequency (TCF) as high as 59.2× compared to that of a regular resonator-based counterpart using frequency combs in an internal resonating (IR) beam resonator. Particularly, the time-varying amplitude modulated resonance signal due to energy exchange between the 1st and 3rd flexural modes in the IR resonator yields combs in the frequency domain. The comb generation occurs within a certain frequency range, and the comb spacing exhibits a certain dependency on the offset from the onset IR. By driving the resonator at a fixed frequency around its 1st mode, the offset changes and therefore the comb spacing changes in response to temperature changes, yielding a TCF up to -11,481 ppm/°C in the comb spacing shift, a 59.2× higher against the -194 ppm/°C of the resonance frequency of a reference beam resonator. The results verify the IR induced frequency combs can serve as a promising approach towards ultrasensitive sensors.
Subjects
CMOS-MEMS | Frequency combs | internal resonance | temperature sensors
Type
conference paper