Solid Electrolyte Capacitor Edge Polymer Thickness Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Tantalum capacitors face reliability issues due to non-uniform polymer film thickness, which affects thermal stability and moisture resistance, making it difficult to achieve high-reliability and high-capacity devices.
Innovation Solution
A solid electrolyte capacitor design with a conductive polymer layer where the thickness ratio between the edge and central portions of the sintered body is controlled between 0.35 and 0.9, using a polymer slurry with conductive particles like graphene, carbon nanotubes, and carbon black to ensure uniformity and enhance thermal stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a polymer layer is applied above the sintered body, then the capacitor structure is formed, but the film thickness becomes non-uniform causing reliability deterioration
Solution Approach 1:
The patent applies local quality by creating different polymer layer thicknesses in different regions of the sintered body. The edge portion has a controlled thickness ratio (t2/t1) between 0.35 and 0.95, while the central portion has a different thickness. This non-uniform thickness distribution is intentionally designed to compensate for the coffee ring effect and improve overall reliability.
Solution Approach 2:
The patent changes the thickness parameter of the polymer layer in different regions. By controlling the thickness ratio (t2/t1) of the edge portion relative to the central portion within a specific range (0.35-0.95), the patent optimizes the film uniformity and prevents reliability deterioration caused by non-uniform thickness.
2Temperature
If the polymer layer thickness is increased to improve reliability, then thermal stability improves, but moisture resistance deteriorates due to non-uniform distribution
Solution Approach 1:
The patent addresses the contradiction between thermal stability and moisture resistance by applying different thicknesses of polymer layer in different regions. The controlled thickness ratio (t2/t1) ensures that the edge portion has sufficient thickness for thermal stability while maintaining appropriate thickness for moisture resistance, preventing the harmful effects of non-uniform distribution.
3Ease of manufacture
If the polymer layer is applied uniformly across the sintered body, then manufacturing is simplified, but edge and central portions have insufficient thickness control
Solution Approach 1:
The patent resolves this contradiction by defining specific thickness requirements for different regions. The edge portion thickness (t2) is controlled to be 0.35-0.95 times the central portion thickness (t1), providing precise thickness control while maintaining a relatively simple manufacturing process.
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 controlled thickness ratio improves thermal stability and reliability by reducing moisture influence, enabling the production of high-reliability and high-capacity tantalum capacitors with optimized edge and central polymer layer thickness.
Implementation Method 1
a sintered body formed by sintering a molded body containing metal powder
Implementation Method 2
a conductive polymer layer disposed above the sintered body
Data Source
AI summary
A solid electrolyte capacitor includes a sintered body formed by sintering a molded body containing metal powder; and a conductive polymer layer disposed above the sintered body. A ratio (t2/t1) of a thickness (t2) of the conductive polymer layer in an edge portion of the sintered body to a thickness (t1) of the conductive polymer layer in a central portion of the sintered body satisfies 0.35≤t2/t1≤0.9.