声表面波（SAW）技术广泛应用于无线通信、传感器、微流体、光子与量子信息通信等领域。然而，受限于制造技术的发展，SAW器件的频率通常在几个吉赫（GHz）以内，严重限制了SAW器件在5G通信、高精度传感、光子与量子控制中的应用。针对上述关键问题，本文提出将极端纳米制造技术与LiNbO₃/SiO₂/SiC异质结构衬底相结合的策略，成功制备出波长为160 nm的超高频SAW器件，其高阶模态谐振频率高达约44 GHz，获得的机电耦合系数高达15.7%。基于LiNbO₃/SiO₂/SiC 异质结构衬底的超高频SAW呈现出多种模态，理论仿真分析确定了高阶声波模态的波模态。进行了超高频SAW微质量传感应用研究，其最高质量灵敏度高达33151.9 MHz mm² μg⁻¹，比频率为978 MHz的传统SAW器件质量灵敏度高4000 倍，是传统石英微天平（QCM）器件质量灵敏度的1011倍。

Surface acoustic wave (SAW) technology has been extensively explored for wireless communication, sensors, microfluidics, photonics, and quantum information processing. However, due to fabrication issues, the frequencies of SAW devices are typically limited to within a few gigahertz, which severely restricts their applications in 5G communication, precision sensing, photonics, and quantum control. To solve this critical problem, we propose a hybrid strategy that integrates a nanomanufacturing process (i.e., nanolithography) with a LiNbO3/SiO2/SiC heterostructure and successfully achieve a record-breaking frequency of about 44 GHz for SAW devices, in addition to large electromechanical coupling coefficients of up to 15.7%. We perform a theoretical analysis and identify the guided higher order wave modes generated on these slow-on-fast SAW platforms. To demonstrate the superior sensing performance of the proposed ultra-high-frequency SAW platforms, we perform micro-mass sensing and obtain an extremely high sensitivity of approximately 33151.9 MHz·mm²·μg⁻¹, which is about 10¹¹ times higher than that of a conventional quartz crystal microbalance (QCM) and about 4000 times higher than that of a conventional SAW device with a frequency of 978 MHz.