2025/09/02 by Gaia Giubilei, Farah Ben Ayed, Giubilei, Gaia +15
Chemical Engineering · Engineering · #Acoustic Wave Resonator Technologies #Analytical Chemistry and Sensors #FOS: Electrical engineering #FOS: Physical sciences #Gas Sensing Nanomaterials and Sensors #Instrumentation and Detectors (physics.ins-det) #Systems and Control (eess.SY) #electronic engineering #information engineering
paper · pdf · doi:10.48550/arxiv.2509.04511
openalex publication_date 2025/09/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
This work presents a novel hydrogen sensor based on 30% scandium-doped aluminum nitride (ScAlN) laterally vibrating resonators (LVRs) functionalized with a palladium (Pd) thin film. The micro-electro-mechanical system (MEMS) device operates by detecting shifts in resonant frequency resulting from hydrogen absorption in the Pd layer. The sensor demonstrates a high mechanical quality factor (Qm) of 820, an electromechanical coupling coefficient (kt2) of 3.18%, and an enhanced responsivity of 26 Hz/ppm in the low-parts per million (ppm) range, making it highly suitable for hydrogen leak detection. Compared to existing MHz-range technologies, the sensor achieves up to 50x higher sensitivity, while also offering multi-frequency definition in a single lithographic step, minimal footprint, and the highest quality factor among comparable miniaturized platforms.