Double-Layer BAW Resonator Structure for Higher Power Handling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional bulk acoustic wave (BAW) resonators face limitations in power handling capabilities, especially in high-frequency applications, due to small area electrodes and poor energy confinement.
Innovation Solution
The proposed acoustic resonator device consists of two piezoelectric layers with similar acoustic impedance and opposite phase wave excitation, allowing for efficient excitation of the second thickness plate resonance and optimizing the interface for low stress regions, thereby enhancing power handling capabilities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If a single piezoelectric layer is used in conventional BAW resonators, then the device structure is simple, but the power handling capability is limited
Solution Approach 1:
The piezoelectric layer is divided into two separate piezoelectric layers (first and second piezoelectric layers) with similar acoustic impedances. This segmentation allows the resonator to handle higher power by distributing the acoustic energy across multiple layers, thereby improving power handling capability while managing structural complexity through systematic design.
Solution Approach 2:
The invention uses a composite structure with two piezoelectric layers having similar acoustic impedances. This composite configuration enables better energy distribution and stress management compared to a single layer, enhancing power handling capability while maintaining a manageable device structure through optimized layer integration.
2Power
If the piezoelectric layer thickness is increased to improve power handling, then the energy confinement is improved, but the resonator area and device size increase
Solution Approach 1:
Instead of using a single thick piezoelectric layer that would increase resonator area, the invention segments the thickness into two thinner piezoelectric layers. This segmentation achieves the required energy confinement and power handling capability while maintaining a compact resonator footprint, effectively decoupling power handling improvement from area increase.
Solution Approach 2:
The invention transitions from a single-layer vertical structure to a multi-layer vertical structure, utilizing the thickness dimension more efficiently. By stacking two piezoelectric layers, the device achieves enhanced energy confinement and power handling in the vertical dimension without expanding the horizontal resonator area.
3Area of stationary object
If the piezoelectric layer thickness is reduced to decrease device size, then the resonator area is reduced, but the energy confinement deteriorates
Solution Approach 1:
The invention segments the piezoelectric structure into two layers, where each layer can be optimized for specific functions. This segmentation allows maintaining thin layer dimensions for compact area while achieving effective energy confinement through the combined effect of multiple layers with optimized thicknesses and acoustic impedance matching.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration enables improved power handling by evenly distributing elastic energy across the layers, increasing the resonator's thickness and area, and reducing energy density, thus overcoming the limitations of conventional BAW resonators.
Implementation Method 1
a first piezoelectrical layer and a second piezoelectric layer... the first electrode and the second electrode are arranged to convert an electrical signal into an acoustic wave in the first piezoelectrical layer and the second piezoelectric layer
Data Source
AI summary
Embodiments of the invention relate to an acoustic resonator device for excitation of bulk acoustic waves (BAW) with enhanced power handling capabilities. The acoustic resonator device has a composite piezoelectrical platelet which comprises a first piezoelectrical layer and a second piezoelectric layer with the same or similar acoustic impedance but with opposite phase wave excitation for a given wave polarization. The dimensions of the composite piezoelectrical platelet for a given static capacitance can hence be increased, while maintaining a wide bandwidth of the acoustic resonator device.