AlScN Thin Films for the Piezoelectric Transduction of Suspended Microchannel Resonators
Suspended microchannel resonators (SMRs) are powerful tools for mass, density, and viscosity sensing. Among various transduction methods, full piezoelectric transduction offers key advantages, including on-chip integration, low energy dissipation, and linear response. This work explores sub-200 nm Al<sub>0.6</sub>Sc<sub>0.4</sub>N thin films for SMR transduction, benchmarking them against their well-established AlN predecessor. By integrating the piezoelectric stack into low-stress silicon nitride (ls-SiN<sub>x</sub>) beam resonators, we investigate the impact of bottom electrode design, photoresist removal prior to deposition, and deposition bias on film quality. Characterization includes X-ray diffraction (XRD), scanning electron microscopy (SEM), d<sub>31</sub> piezoelectric coefficient, relative dielectric permittivity, and breakdown field measurements. Results illustrate the impacts of the studied parameters and demonstrate a fourfold increase in d<sub>31</sub>, compared to AlN, confirming the strong potential of Al<sub>0.6</sub>Sc<sub>0.4</sub>N for high-performance SMR transduction.
Authors
- Luis Guillermo Villanueva (ORCID: https://orcid.org/0000-0003-3340-2930)
- Marco Liffredo (ORCID: https://orcid.org/0000-0002-4643-8927)
- Yara Abdelaal (ORCID: https://orcid.org/0009-0003-7151-3102)
Institutions
- Swiss Polar Institute (CH)
- École Polytechnique Fédérale de Lausanne (CH)
Publication Details
- Journal
- Sensors
- Published
- 2025-08-31
- DOI
- https://doi.org/10.3390/s25175370
- Primary Topic
- Acoustic Wave Resonator Technologies
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- National Science Foundation
- École Polytechnique Fédérale de Lausanne
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung