Suppressing acoustomigration and temperature rise for high-power robust acoustics

High-frequency acoustic wave transducers, favored for their compact size, are not only dominating mobile handsets but are also expanding into various interdisciplinary fields. However, as strong vibration can "shake off" substances and produce heat, a long-standing bottleneck has been the ability to harness acoustics under high-power loads, especially for interdigital-transducer-based surface acoustic wave devices. To suppress three fundamental mechanisms: self-heating, thermal instability, and acoustomigration, we propose a layered acoustic wave platform utilizing a quasi-infinite multifunctional top layer that redefines mechanical and thermal boundary conditions. The proposed transducer achieves a 70% reduction in temperature rise, a temperature coefficient of frequency of -13 ppm/°C, and an unprecedented threshold power density of 45.61 dBm/mm² - over one order of magnitude higher than that of state-of-the-art thin-film surface acoustic wave counterparts. This architecture enables scalable deployment of high-power acoustic wave components in space-constrained hybrid platforms and opens the functional diversification of acoustic wave transducers.