Recessed Lower Electrode Layout for Piezoelectric Vibration Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The vibration attenuation in piezoelectric devices due to transmission through the lower electrode layer to the periphery reduces the excitation efficiency.
Innovation Solution
A piezoelectric device design with a recessed lower electrode layer and a protruding base support structure, where the lower electrode layer is confined within the recess, and a single crystal piezoelectric layer is used, enhancing the excitation efficiency by minimizing vibration loss.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the lower electrode layer extends to the periphery of the piezoelectric device, then the electrode structure is reinforced and electrical connection is improved, but vibration is transmitted to the periphery causing attenuation and reduced excitation efficiency
Solution Approach 1:
The lower electrode layer is segmented into two distinct regions: a first lower electrode layer confined within the recess that contacts the piezoelectric layer, and a second lower electrode layer on the base surface that provides structural reinforcement and electrical connection. This segmentation allows the first layer to avoid transmitting vibration to the periphery while the second layer maintains structural integrity and electrical connectivity.
Solution Approach 2:
Different regions of the lower electrode structure are given different functions and properties. The first lower electrode layer within the recess is optimized for electrical contact with the piezoelectric layer without extending to the periphery, while the second lower electrode layer on the base surface provides structural support and electrical connection to external circuits. This local differentiation resolves the contradiction by assigning specific roles to specific regions.
2Loss of energy
If the lower electrode layer is confined only within the recess, then vibration attenuation is reduced and excitation efficiency is improved, but electrical connection and structural support may be insufficient
Solution Approach 1:
The lower electrode layer is divided into functional segments: the first segment within the recess maintains minimal vibration transmission, while the second segment extending on the base surface provides robust electrical connection and structural support. This segmentation enables both vibration reduction and reliable electrical connection to be achieved simultaneously.
Solution Approach 2:
The recess structure acts as an intermediary element between the piezoelectric layer and the base. By confining the first lower electrode layer within this intermediary recess and separating it from the periphery, the design reduces vibration transmission while the second lower electrode layer on the base surface serves as an intermediary for electrical connection, thus resolving the contradiction.
3Loss of energy
If the piezoelectric layer is subjected to high voltage for strong excitation, then excitation efficiency is improved, but cracks may occur and foreign matter may enter through the periphery
Solution Approach 1:
The recess structure and the configuration of the lower electrode layer provide preliminary protection against crack propagation and foreign matter entry. By confining the first lower electrode layer within the recess and preventing it from reaching the periphery, the design creates a protective barrier that prevents cracks from initiating at the periphery and blocks foreign matter from entering through peripheral gaps, thus enabling high-voltage operation with improved reliability.
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
The design improves excitation efficiency by reducing vibration attenuation and supports the layered structure, increasing reliability and uniformizing polarization, thus enhancing overall performance.
Implementation Method 1
a single crystal piezoelectric layer and a pair of electrode layers to apply voltage to the single crystal piezoelectric layer
Data Source
AI summary
In a piezoelectric device, a layered portion includes, at a position at least above a recess, a single crystal piezoelectric layer and a pair of electrode layers to apply voltage to the single crystal piezoelectric layer. At least a portion of the pair of electrode layers includes a lower electrode layer extending along a surface of the single crystal piezoelectric layer, the surface being closer to a base. The lower electrode layer is present only inside the recess.