AlScN Thin Films for the Piezoelectric Transduction of Suspended Microchannel Resonators
Abstract
Highlights
- Demonstration of a fourfold increase in the d31 piezoelectric coefficient Al0.6Sc0.4N films compared to AlN.
- Examination of the influence of bottom electrode patterning design, photoresist removal, and deposition bias on film quality and transduction performance.
- Establishing Al0.6Sc0.4N as a promising material for high-performance, fully piezoelectrically transduced suspended microchannel resonators (SMRs).
Abstract
1. Introduction
2. Materials and Methods
2.1. Film Deposition
2.2. Film Characterization
2.3. Device Fabrication
- The first design features rectangular structures over the future resonator areas, connected to 400 µm × 400 µm pads, covering ~3.7% of the wafer’s area.
- The second design adds continuous metal across the wafer, separated by trenches for isolation, mimicking non-patterned coverage with ~97.5% metal coverage.
2.4. Measurement of the d31 Coefficient
2.5. Measurement of the Breakdown Field and Dielectric Constant
3. Results
3.1. XRD Analysis
3.2. SEM Examination
3.3. Measurement of the d31 Coefficient, the Dielectric Relative Permittivity, and the Breakdown Field
4. Discussion
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
Abbreviations
SMR | Suspended microchannel resonator |
Ls-SiNx | Low-stress silicon nitride |
XRD | X-ray diffraction |
SEM | Scanning electron microscopy |
PZT | Lead Zirconate Titanate Pb [ZrxTi1−x] O3 |
AOGs | Abnormally oriented grains |
IR | Infrared |
SAW | Surface acoustic waves |
BAW | Bulk acoustic waves |
LPCVD | Low-pressure chemical vapor deposition |
IBE | Ion beam etching |
DRIE | Deep reactive ion etching |
DHM | Digital holographic microscope |
FWHM | Full-width half-maximum |
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Bottom Electrode Design | Resist Removal Method | Film Thickness | Bias |
---|---|---|---|
97.5% Metal Coverage | Dry | 100 nm | 0 W |
1 W | |||
200 nm | 0 W | ||
1 W | |||
Dry + Wet | 100 nm | 0 W | |
1 W | |||
200 nm | 0 W | ||
1 W | |||
3.7% Metal Coverage | Dry | 100 nm | 0 W |
1 W | |||
200 nm | 0 W | ||
1 W |
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Abdelaal, Y.; Liffredo, M.; Villanueva, L.G. AlScN Thin Films for the Piezoelectric Transduction of Suspended Microchannel Resonators. Sensors 2025, 25, 5370. https://doi.org/10.3390/s25175370
Abdelaal Y, Liffredo M, Villanueva LG. AlScN Thin Films for the Piezoelectric Transduction of Suspended Microchannel Resonators. Sensors. 2025; 25(17):5370. https://doi.org/10.3390/s25175370
Chicago/Turabian StyleAbdelaal, Yara, Marco Liffredo, and Luis Guillermo Villanueva. 2025. "AlScN Thin Films for the Piezoelectric Transduction of Suspended Microchannel Resonators" Sensors 25, no. 17: 5370. https://doi.org/10.3390/s25175370
APA StyleAbdelaal, Y., Liffredo, M., & Villanueva, L. G. (2025). AlScN Thin Films for the Piezoelectric Transduction of Suspended Microchannel Resonators. Sensors, 25(17), 5370. https://doi.org/10.3390/s25175370