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arXiv · 2504.19936

Ku-Band AlScn-On-Diamond SAW Resonators with Phase Velocity above 8600 m/s

Tzu-Hsuan Hsu·Kapil Saha·Jack Kramer·Omar Barrera·Pietro Simoni·Matteo Rinaldi·Ruochen Lu
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Abstract

In this work, an Aluminum Scandium Nitride (AlScN) on Diamond Sezawa-mode surface acoustic wave (SAW) platform for RF filtering at Ku-band (12-18 GHz) is demonstrated. Thanks to the high acoustic velocity and low-loss diamond substrate, the prototype resonator at 12.9 GHz achieves a high phase velocity ($v_p$) of 8671 m/s, a maximum Bode-$Q$ of 408, and coupling coefficient ($k_{\mathrm{eff}}^2$) of 2.1%, outperforming high-velocity substrates such as SiC and sapphire by more than 20% in velocity. Resonators spanning 8-18 GHz are presented. The platform's high power handling above 12.5 dBm is also experimentally validated.

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BibTeXRIS

Tzu-Hsuan Hsu, Kapil Saha, Jack Kramer, Omar Barrera, Pietro Simoni, Matteo Rinaldi, Ruochen Lu. 2025-04-28. Ku-Band AlScn-On-Diamond SAW Resonators with Phase Velocity above 8600 m/s. https://doi.org/10.1109/transducers61432.2025.11109438

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