A dispersion-guided design methodology for super-high-frequency solidly mounted resonators

Area of Science:

• Acoustic physics
• Materials science
• Radio frequency engineering

Background:

• Solidly Mounted Resonators (SMRs) are vital for RF filters and sensors.
• Miniaturization for 6G communication systems causes frequency deviation in conventional SMR designs due to electrode effects.
• Effective acoustic energy confinement is challenging in advanced SMR structures.

Purpose of the Study:

• To propose a novel design and optimization approach for SMR structures.
• To address frequency deviation and acoustic energy confinement issues in SMRs for super-high-frequency (SHF) bands.
• To provide a reliable method for designing SMRs for next-generation RF devices.

Main Methods:

• Derivation of dispersion equations for laminated Bragg reflectors using Stroh formalism and transfer matrix method.
• Application of the Moduli Ratio Convergence Method to solve complex dispersion equations for intricate SMR configurations.
• Redesign of Bragg reflectors based on actual cutoff frequencies and global scaling adjustment for precise frequency tuning.

Main Results:

• Optimized SMR structures exhibit highly concentrated acoustic energy within the resonant region.
• Reduced energy penetration into the Bragg reflector and minimal energy leakage into the substrate.
• Demonstrated effectiveness of the novel design approach through structural dispersion analysis.

Conclusions:

• The proposed method offers a reliable and efficient approach for designing SMRs in the SHF band.
• The optimized SMR structures are suitable for next-generation RF devices operating at higher frequencies.
• This research provides valuable guidance for advancing RF filter and sensor technology.