LAUSR

In this work, a novel design scheme for a high-performance surface acoustic wave (SAW) filter with dual acoustic mode hybrid integration is proposed. Based on X-cut LiNbO₃/SiO₂/SiC (LNOSiC) hetero-substrate, the dual-mode ladder-type filter employs the high-electromechanical-coupling shear horizontal (SH) mode as the main mode for parallel resonators and high-power longitudinal leaky (LL) mode for series resonators, respectively. The fabricated hybrid dual-mode filter aiming at the n79 band shows a large 3-dB fractional bandwidth (FBW) ${}_{\mathrm {3dB}}$ ) of 12.4%, a low insertion loss (IL) of 1.05 dB, high peak power handling of 29 dBm, and a high out-of-band (OoB) rejection of 38 dB over a wide frequency range. Low-loss SH-SAW and LL-SAW filters are also fabricated for comparative analysis. The hybrid filter demonstrates an FBW ${}_{\mathrm {3dB}}~1.3$ times larger than the LL-SAW filter, with a P1dB power handling nearly 2.5 times that of SH-SAW filters. These results demonstrate the comprehensive performance advantages of the proposed dual-mode filter technology as well as its strong potential for advanced 5G communication systems.