Power Handling Modeling of Micro- and Nanoacoustic Resonators

High-performance RF front-end components demand acoustic filters that posses high frequency, low insertion loss, and robust power handling. Scandium-doped Aluminum Nitride (ScAlN) provides the necessary material platform, while Cross-Sectional Lame Mode Resonators (CLMRs) enable high quality factor (Q) and electromechanical coupling (kt2) to extend operation to the frequencies of interest, such as the Ku-band. However, the power handling of state-of-the-art resonators remains a major limitation, primarily due to self-heating and electromigration in the metal of the interdigitated electrodes (IDT). In this work, a finite element (FE) model to describe the thermal processes behind the power handling performance of acoustic resonators is developed. The model is analyzed under the worst-case scenario, corresponding to the resonant frequency, where the current and power dissipation are maximized. It accounts for electro-thermal effects, providing predictions of device reliability under high-power excitation, and is validated with experimental measurements on fabricated ScAlN CLMRs. The proposed model provides accurate prediction of thermal behavior in acoustic resonators, offering a reliable framework for the design and optimization of next-generation RF front-end components.