Novel Method for Extracting Material Constants of Epitaxial Wurtzite AlScN Films on Sapphire Using Higher Order Surface Acoustic Wave Modes
- Partial substitution of Al atoms with Sc in wurtzite AlN crystals increases the piezoelectric constants. This leads to an increased electromechanical coupling, which is required for high bandwidths in piezo-acoustic filters. The crystal bonds in Ah-xScxN (AlScN) are softened as function of Sc atomic percentage x, leading to reduction of phase velocity in the film. Combining high Sc content AlScNPartial substitution of Al atoms with Sc in wurtzite AlN crystals increases the piezoelectric constants. This leads to an increased electromechanical coupling, which is required for high bandwidths in piezo-acoustic filters. The crystal bonds in Ah-xScxN (AlScN) are softened as function of Sc atomic percentage x, leading to reduction of phase velocity in the film. Combining high Sc content AlScN films with high velocity substrates favors higher order guided surface acoustic wave (SAW) modes [1]. This study investigates higher order SAW modes in epitaxial AlScN on sapphire (Al2O3). Their dispersion for Pt metallized epitaxial AlScN films on Al2O3was computed for two different propagation directions. Computed phase velocity dispersion branches were experimentally verified by the characterization of fabricated SAW resonators. The results indicated four wave modes for the propagation direction (0°, 0°, 0°), featuring 3D polarized displacement fields. The sensitivity of the wave modes to the elastic constants of AlScN was investigated. It was shown that due to the 3D polarization of the waves, all elastic constants have an influence on the phase velocity and can be measured by suitable weighting functions in material constant extraction procedures.…
Document Type: | Conference Proceeding |
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Conference Type: | Konferenzartikel |
Zitierlink: | https://opus.hs-offenburg.de/4531 | Bibliografische Angaben |
Title (English): | Novel Method for Extracting Material Constants of Epitaxial Wurtzite AlScN Films on Sapphire Using Higher Order Surface Acoustic Wave Modes |
Conference: | 2020 IEEE International Ultrasonics Symposium (IUS), 7-11 Sept. 2020, Las Vegas, NV, USA |
Author: | Niclas M. Feil, Elena MayerStaff Member, Björn Christian, Anli Ding, Agnė Žukauskaitė, Oliver Ambacher |
Year of Publication: | 2020 |
Publisher: | IEEE |
Page Number: | 4 |
Parent Title (English): | 2020 Symposium Proceedings |
ISBN: | 978-1-7281-5448-0 (digital) |
ISBN: | 978-1-7281-5449-7 (Print on Demand) |
ISSN: | 1948-5727 (digital) |
ISSN: | 1948-5719 (Print on Demand) |
DOI: | https://doi.org/10.1109/IUS46767.2020.9251767 |
Language: | English | Inhaltliche Informationen |
Institutes: | Fakultät Wirtschaft (W) |
Institutes: | Bibliografie | Formale Angaben |
Open Access: | Closed Access |
Licence (German): | Urheberrechtlich geschützt |