Multilayer Ceramic Capacitor Electrode Gradient for High-Frequency ESL
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional multilayer ceramic capacitors face excessive equivalent series inductance (ESL) when operating in high frequency regions, hindering the achievement of both low ESL and large capacitance.
Innovation Solution
The multilayer ceramic capacitors are designed with specific internal electrode configurations, including end and lateral surface internal electrodes, which are strategically positioned and sized to enhance their cross-sectional area, coverage, and thickness in the high-frequency region, while maintaining smaller dimensions in the low-frequency region, thereby reducing ESL.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the thickness of dielectric layers and internal electrode layers is reduced to increase capacitance, then the capacitance increases, but the ESL becomes excessive
Solution Approach 1:
The patent applies local quality by making the internal electrodes have different cross-sectional areas at different positions along the lamination direction. Specifically, the internal electrodes have a larger cross-sectional area in the first region (adjacent to the first main surface) compared to the second region (adjacent to the second main surface). This non-uniform distribution optimizes the current path and reduces ESL in the high-frequency region while maintaining capacitance, resolving the contradiction between increased capacitance and reduced ESL.
2Quantity of substance
If the number of laminated layers is increased to achieve larger capacitance, then the capacitance increases, but the device complexity and ESL increase
Solution Approach 1:
The patent divides the multilayer body into regions with different internal electrode configurations. The first region has internal electrodes with larger cross-sectional areas to reduce ESL, while the second region has internal electrodes with smaller cross-sectional areas to maintain capacitance. This regional differentiation allows the capacitor to achieve large capacitance without proportionally increasing the number of laminated layers, thus reducing device complexity.
3Object-affected harmful factors
If internal electrodes are made larger to reduce ESL, then the ESL decreases, but the capacitance is reduced
Solution Approach 1:
The patent implements local quality by creating a non-uniform cross-sectional area distribution of internal electrodes along the lamination direction. The first region (adjacent to the first main surface) has internal electrodes with larger cross-sectional areas to reduce ESL for high-frequency signals, while the second region (adjacent to the second main surface) has internal electrodes with smaller cross-sectional areas to maintain capacitance. This spatial variation in electrode dimensions allows simultaneous optimization of both ESL and capacitance.
Solution Approach 2:
The patent resolves the contradiction by introducing a dimensional variation in the internal electrode cross-sectional area along the lamination direction (the third dimension). Instead of using uniform electrodes throughout, the electrode cross-section changes systematically from the first region to the second region, adding a dimensional gradient that enables independent optimization of ESL and capacitance properties.
Data Source
AI summary
A multilayer ceramic capacitor includes end surface internal electrodes each exposed at end surfaces of a laminate, and side surface internal electrodes each exposed at side surfaces of the laminate. An end surface internal electrode closest to a first-main-surface side has a greater cross-sectional area in a first reference cross-section than an end surface internal electrode with a greatest cross-sectional area in the first reference cross-section among the end surface internal electrodes in either of a second-main-surface-side region and an intermediate region. A side surface internal electrode closest to the first-main-surface side has a greater cross-sectional area in a second reference cross-section than a side surface internal electrode that has a greatest cross-sectional area in the second reference cross-section among the side surface internal electrodes in either of the second-main-surface-side region and the intermediate region.