Multilayer Capacitor Warpage Suppression via Segmented Lamination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing multilayer capacitor manufacturing methods face challenges in achieving high yields and minimizing warpage, particularly for large capacitance capacitors, as they often result in increased foreign matters, defects, and fluctuating breakdown voltage and capacitance, with conventional methods struggling to completely eliminate warpage and maintain productivity.
Innovation Solution
A multilayer capacitor design involving two or more laminated bodies with alternately deposited resin and metal layers, where the laminated bodies are bonded at specific surfaces with recess portions to eliminate warpage, and both end surfaces are covered with a metal material functioning as external electrodes, enhancing adhesion and reducing defects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the number of windings of metallized plastic films is increased to achieve large capacitance, then capacitance increases, but foreign matters and defects between films increase
Solution Approach 1:
The patent divides the capacitor structure into multiple separate laminated bodies, each with a manageable number of windings. By bonding these segmented bodies together, the total capacitance is achieved without requiring any single body to have excessive windings, thereby avoiding the accumulation of foreign matters and defects that would occur in a single thick laminated structure.
2Quantity of substance
If the film formation period is extended to manufacture large capacitance single type multilayer capacitor, then capacitance increases, but breakdown voltage and capacitance fluctuate and foreign matter defects increase
Solution Approach 1:
The capacitor is constructed by bonding multiple laminated bodies together, each formed during a relatively short film formation period. This segmentation allows each individual body to be formed under stable conditions, avoiding the cumulative fluctuations in breakdown voltage and capacitance that would occur during an extended single continuous film formation process.
3Shape
If hot pressing is performed to flatten laminated bodies and reduce warpage, then warpage decreases, but productivity is lowered due to long-term flattening requirement
Solution Approach 1:
The laminated bodies are pre-flattened to a sufficient degree before the bonding process, eliminating the need for prolonged flattening after assembly. This preliminary action ensures that warpage is reduced to an acceptable level prior to bonding, allowing the process to proceed efficiently without compromising the flatness of the final product.
Solution Approach 2:
The flattening and bonding operations are merged into a coordinated sequence where flattening is performed immediately before bonding. This integration allows the flattening process to be optimized for the specific bonding requirements, reducing the overall time required compared to separate, sequential operations.
4Shape
If complete flattening is performed to eliminate warpage of laminated bodies, then warpage is removed, but productivity is significantly reduced
Solution Approach 1:
Instead of performing complete flattening to eliminate all warpage, the patent applies partial flattening that reduces warpage to a level sufficient for the bonding process. This partial action achieves the necessary shape control without the excessive time investment required for complete flattening, thereby maintaining high productivity.
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 approach allows for the production of multilayer capacitors with suppressed warpage, improved yield, and increased capacitance, while maintaining high quality and reducing the occurrence of defects and quality variations, even at thicker dimensions.
Implementation Method 1
depositing a metal raw material and a resin raw material alternately on a support body
Implementation Method 2
bonding two or more such laminated bodies together
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
Provided is a multilayer capacitor that can be manufactured with high yields and whose warpage is suppressed. The multilayer capacitor includes two or more laminated bodies (20A, 20B) which are bonded together, the two or more laminated bodies each including resin layers and metal layers which are alternately laminated a plurality of times in a thickness direction and each being warped and having front and rear surfaces covered with surface layers containing a resin material, one of the front and rear surfaces being formed of a first surface (30) as a smooth surface having no recess portion, another of the front and rear surfaces being formed of a second surface (32) having a recess portion (34), in which at least two adjacent laminated bodies (20A, 20B) are bonded together at the first surfaces (30) or the second surfaces (32). Also provided are a manufacturing method for the multilayer capacitor, and a circuit board and an electronic device which use the multilayer capacitor.