Multilayer Ceramic Capacitor Electrode Layout for Lower High-Frequency ESL
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Multilayer ceramic capacitors experience high impedance in high frequency bands due to irregular shapes of internal electrode edges causing longer current paths, which is exacerbated by overfiring.
Innovation Solution
The multilayer ceramic capacitors are designed with second internal electrodes featuring regions extending from a first region towards the surfaces, where end edges include protrusions, ensuring current paths remain short and unaffected by irregular edges, thereby reducing equivalent series inductance (ESL) and improving low impedance characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the internal electrode edges are allowed to form irregular shapes during manufacturing, then manufacturing complexity is reduced, but the current path length increases causing high impedance in high frequency bands
Solution Approach 1:
The patent applies local quality by making only the end edges of the second internal electrode protrude towards the fifth and sixth surfaces, while other portions maintain conventional configurations. This localized modification ensures that the protrusions specifically address the high frequency impedance issue without unnecessarily complicating the overall manufacturing process or affecting other functional areas of the capacitor.
2Productivity
If overfiring is used to densify the ceramic body, then manufacturing efficiency is improved, but the internal electrode edges become irregular causing longer current paths
Solution Approach 1:
The patent applies preliminary anti-action by pre-compensating for the edge irregularities that will occur during overfiring. The internal electrodes are designed with protrusions that extend beyond the expected irregular edge boundaries, ensuring that even after overfiring causes edge deformation, the effective current path remains short and the impedance characteristics are maintained.
3Reliability
If the current path is shortened to reduce ESL, then low impedance characteristics are improved, but the internal electrode structure becomes more complex
Solution Approach 1:
The patent applies local quality by making only the end edges of the second internal electrode protrude towards the fifth and sixth surfaces, while other portions maintain conventional configurations. This localized modification ensures that the protrusions specifically address the high frequency impedance issue without unnecessarily complicating the overall manufacturing process or affecting other functional areas of the capacitor.
Solution Approach 2:
The patent applies partial action by extending only the end edges of the second internal electrode towards the fifth and sixth surfaces, rather than modifying the entire electrode structure. This partial modification is sufficient to achieve the desired short current path effect for reducing ESL and improving low impedance characteristics, while avoiding unnecessary complexity in other areas of the electrode design.
Data Source
AI summary
A multilayer ceramic capacitor includes a laminate including first, second, third, fourth, fifth, and sixth surfaces, a first external electrode on the third surface, a second external electrode on the fourth surface, a third external electrode on the fifth surface, and a fourth external electrode on the sixth surface. The laminate includes an inner layer dielectric layer, a first internal electrode including one end in a first direction exposed on the third surface and the fourth surface, and a second internal electrode including one end in a second direction exposed on the fifth surface and the sixth surface. The second internal electrode includes a first region inside the laminate, and a second region extending from the first region to the fifth surface and the sixth surface, and protrusion portions on at least one of end edges facing each other in the first direction of the second region.