Dissertation Talk: Sub-100nm-Gap-Enabled Temperature-Insensitive MEMS Resonators

Event details Date: Friday, July 10, 2026 Time: 12:00 PM to 12:00 PM Location: Cory 521 Type: Lecture / Workshop Audience: Faculty,Students About this event Microelectromechanical systems (MEMS) are widely used in modern sensing and timing applications for their low power, small size, high quality factor (Q) and batch-fabrication compatibility, from the oscillators that tell time and synchronize communications to the sensors that monitor vehicles – enabling capabilities such as hydrogen tank health monitoring for future fuel-cell electric vehicles (FCEV) and faster brake response. The key to achieving this is the use of sub-100-nm transducer gaps in MEMS resonators to suppress environmental interferences, e.g. due to temperature changes. In this talk, I will first present the design, fabrication and measurement of polysilicon ring resonant strain sensors that use differential output and curve-fitting to suppress Young’s modulus temperature sensitivity. Because the same mechanism also lets a resonator sense its own temperature, I will then present a CVD diamond ring resonator that compensates its own temperature-induced frequency drift for ultra-stable oscillator applications. Finally, I will show how localized annealing can selectively grow high-quality Silicon Carbide (SiC) on polysilicon resonators, providing boosted Q and enabling in-situ on-demand localized annealing to restore devices even after packaging. Official event details: https://events.berkeley.edu/eecs/event/323895-dissertation-talk-sub-100nm-gap-enabled