Effects of Electric Bias on Different Sc-Doped AlN-Based Film Bulk Acoustic Resonators

Film bulk acoustic resonators (FBARs) based on aluminum nitride (AlN) and scandium-doped (AlScN) exhibit tremendous application aspects in the radio frequency front-end due to achievable high-frequency characteristics, superior thermal performances compatibility with harsh environments. Delicately controlling resonant (fs) of FBAR is essential for integrating filters or modules. In this work, we provide a practical feasibility adjusting fs AlN AlScN using external direct current electric bias (EDC). When applying negative EDC (the direction along reversed c-axis), shifts lower frequency, whereas positive brings higher fs. order extract equivalent values stiffness coefficient (c33), piezoelectric (e33) dielectric constant (?zz) materials, adopted electromechanical Mason model. The results show that c33 increase change from positive, and, other hand, those e33 ?zz decrease. Our work provides systematic investigation field-influenced stiffening effect films opens frequency-tunable resonators.