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arXiv · 2402.16732

C-Band Lithium Niobate on Silicon Carbide SAW Resonator With Figure-of-Merit of 124 at 6.5 GHz

Tzu-Hsuan Hsu·Joshua Campbell·Jack Kramer·Sinwoo Cho·Ming-Huang Li·Ruochen Lu
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Abstract

In this work, we demonstrate a C-band shear-horizontal surface acoustic wave (SH-SAW) resonator with high electromechanical coupling (kt2) of 22% and a quality factor (Q) of 565 based on a thin-film lithium niobate (LN) on silicon carbide (SiC) platform, featuring an excellent figure-of-merit (FoM = kt2*Q ) of 124 at 6.5 GHz, the highest FoM reported in this frequency range. The resonator frequency upscaling is achieved through wavelength ($\lambda$) reduction and the use of thin aluminum (Al) electrodes. The LN/SiC waveguide and synchronous resonator design collectively enable effective acoustic energy confinement for a high FoM, even when the normalized thickness of LN approaches a scale of 0.5$\lambda$ to 1$\lambda$. To perform a comprehensive study, we also designed and fabricated five additional resonators, expending the $\lambda$ studied ranging from 480 to 800 nm, in the same 500 nm-thick transferred Y-cut thin-film LN on SiC. The fabricated SH-SAW resonators, operating from 5 to 8 GHz, experimentally demonstrate a kt2 from 20.3% to 22.9% and a Q from 350 to 575, thereby covering the entire C-band with excellent performance.

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Tzu-Hsuan Hsu, Joshua Campbell, Jack Kramer, Sinwoo Cho, Ming-Huang Li, Ruochen Lu. 2024-02-26. C-Band Lithium Niobate on Silicon Carbide SAW Resonator With Figure-of-Merit of 124 at 6.5 GHz. https://doi.org/10.1109/jmems.2024.3423768

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