High Q-factor ultra-thin Si nano-resonators for ultra-sensitive gas-sensing applications

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K14513
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 28050:Nano/micro-systems-related
• Research Institution: Kyoto University
• Principal Investigator: BANERJEE AMIT 京都大学, 工学研究科, 講師 (20894794)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: Nanoresonator / NEMS / Si microfabrication / frequency tuning / Q-factor / gas sensing / EBL / DRIE

Outline of Final Research Achievements

Nanoresonator are vibrating nano-mechanical structures that can work as ultrasensitive gas sensors for novel applications in healthcare, environmental, industrial monitoring, etc. Smaller mass and higher Q-factor generally enhances the performance of nanoresonator-based sensors. In this research we have developed ultrathin Si nanoresonators for gas sensing applications.
We developed a scalable fabrication process to make ~ 10 nm wide, ~ 100 micron long ultrathin Si nanoresonator. We achieved remarkable electrostatic tunability in resonance frequency and nonlinearity comparable to atomically-thin resonators. We theoretically and experimentally studied the Q-factor reduction phenomena in nanoscale and identified a cause and potential ways to enhance it. Finally, we conducted high sensitivity CO2 gas sensing experiments with our Si nanoresonators. In summary, we successfully developed scalable, tunable, high Q-factor, ultrathin Si nanoresonators for gas-sensing.

Free Research Field

Nano / micro electromechanical systems

Academic Significance and Societal Importance of the Research Achievements

Nanotechnology can help us build a technologically improved society, for example, by making efficient devices like nanoresonators that are ultrasensitive, small, cheap, and energy efficient. We improved Si nanoresonators so they can be more sensitive, versatile, and easy to make in large numbers.