Piezoelectric Device Electrode Structure for Flexibility and Cost Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing piezoelectric devices face challenges with high rigidity and fragility due to the use of platinum group metals, leading to increased production costs and restricted shape change, while also lacking flexibility and durability.
Innovation Solution
A piezoelectric device configuration featuring a first electrode with a conductive layer made from metals like Ti, Zr, or Au, an intermediate nitrogen compound layer, and a conductive oxide second electrode, which enhances electrical conductivity, flexibility, and adherence, reducing the need for noble metals and lowering production costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If platinum group metals are used as electrode materials, then electrical conductivity and chemical stability are improved, but rigidity increases causing shape change restriction and fragility increases leading to electrode destruction
Solution Approach 1:
The patent employs a composite electrode structure consisting of multiple layers with different functions: a flexible support layer (polymer or metal), a conductive layer (platinum group metal with 0.01-10 μm thickness), and an intermediate layer. This composite structure combines the chemical stability of platinum group metals with the flexibility of the support layer, resolving the contradiction between reliability and strength.
Solution Approach 2:
The electrode is segmented into multiple functional layers rather than using a single material. The conductive layer containing platinum group metals is separated from the flexible support layer by an intermediate layer, allowing each layer to perform its specific function without the drawbacks of the other materials.
2Reliability
If platinum group metals are used as electrode materials, then chemical stability is improved, but production cost increases due to expensive materials
Solution Approach 1:
The patent applies platinum group metals only locally in the conductive layer where electrical conductivity and chemical stability are critical, rather than using them throughout the entire electrode structure. The support layer and intermediate layer use cheaper materials, reducing overall production cost while maintaining reliability where needed.
Solution Approach 2:
By creating a composite electrode structure, the patent reduces the total amount of expensive platinum group metals required compared to using them in a single thick layer, thereby lowering production costs while maintaining chemical stability through the conductive layer.
3Device complexity
If a single conductive layer is used, then device complexity is reduced, but electrical conductivity and durability are insufficient
Solution Approach 1:
The patent uses a composite multi-layer electrode structure where each layer contributes specific properties: the support layer provides mechanical flexibility, the intermediate layer provides adhesion and stress relief, and the conductive layer provides electrical conductivity. This composite approach achieves superior electrical conductivity and durability compared to a single layer, while the overall structure remains relatively simple.
4Stability of the object's composition
If rigid electrode materials are used, then shape change restriction is improved, but flexibility decreases causing electrode fragility
Solution Approach 1:
The electrode is segmented into a flexible support layer and a thin conductive layer containing platinum group metals. The support layer provides the necessary flexibility for shape change, while the thin conductive layer (0.01-10 μm) maintains shape stability and electrical conductivity without restricting movement.
Solution Approach 2:
The patent uses a flexible support layer (polymer or metal) as the base structure and applies a thin film of platinum group metals on top. This thin film configuration allows the electrode to flex and change shape while maintaining electrical conductivity and chemical stability, resolving the contradiction between shape stability and flexibility.
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 proposed configuration achieves excellent electrical conductivity, flexibility, and durability, while minimizing the use of expensive noble metals, resulting in a more cost-effective and reliable piezoelectric device with improved piezoelectric properties.
Implementation Method 1
a piezoelectric layer disposed between the first electrode and the second electrode
Implementation Method 2
The first conductive layer contains one metal selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, Ag, and Au or contains an alloy of at least one metal selected from such a group. The second conductive layer contains a conductive oxide.
Data Source
AI summary
A piezoelectric device includes a first electrode and a facing second electrode, with a piezoelectric layer therebetween. The first electrode includes a first conductive layer, a first intermediate layer that contacts the first conductive layer, a second intermediate layer that contacts the first intermediate layer, and a second conductive layer that contacts the second intermediate layer and the piezoelectric layer. The first conductive layer contains a metal and an alloy. The metal is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, Ag, or Au, and the alloy contains at least one of the foregoing metals. The first intermediate layer contains a nitrogen compound. The second intermediate layer contains a metal and an alloy. The metal is Ti, Zr, W, Ta, or Al, and the alloy contains at least two of the foregoing metals. The second conductive layer contains a conductive oxide.