Selective multiple analyte detection using multi-mode excitation of a MEMS resonator

Usman Yaqoob; Nizar Jaber; Nouha Alcheikh; Mohammad I Younis

doi:10.1038/s41598-022-09365-9

Selective multiple analyte detection using multi-mode excitation of a MEMS resonator

Sci Rep. 2022 Mar 28;12(1):5297. doi: 10.1038/s41598-022-09365-9.

Authors

Usman Yaqoob^#¹, Nizar Jaber^#², Nouha Alcheikh¹, Mohammad I Younis^{3

4}

Affiliations

¹ Physical Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.
² Department of Mechanical Engineering and the Center for Communication Systems and Sensing, King Fahd University of Petroleum and Minerals, Dhahran, 31261, Saudi Arabia.
³ Physical Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia. Mohammad.Younis@kaust.edu.sa.
⁴ Department of Mechanical Engineering, State University of New York at Binghamton, Binghamton, NY, 13902, USA. Mohammad.Younis@kaust.edu.sa.

^# Contributed equally.

Abstract

This work reports highly selective multiple analyte detection by exploiting two different mechanisms; absorption and thermal conductivity using a single MEMS device. To illustrate the concept, we utilize a resonator composed of a clamped-guided arch beam connected to a flexural beam and a T-shaped moveable mass. A finite element model is used to study the mode shapes and mechanical behavior of the device with good agreement reported with the experimental data. The resonator displays two distinct out-of-plane modes of vibration. For humidity detection, we utilize physisorption by functionalizing the surface with graphene oxide (GO), which has strong affinity toward water vapors. The GO solution is prepared and drop-casted over the mass surface using an inkjet printer. On the other hand, cooling the heated flexural beams is used for helium (He) detection (thermal-conductivity-based sensor). The sensor characteristics are extensively studied when the modes are individually and simultaneously actuated. Results affirm the successful utilization of each mode for selective detection of relative humidity and He. This novel mode-dependent selective detection of multiple analytes can be a promising building block for the development of miniature, low-powered, and selective smart sensors for modern portable electronic devices.