Multilayer Ceramic Capacitor Dielectric Structure for Stable High Capacitance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing multilayer ceramic capacitors face challenges in achieving high permittivity, reduced size, increased capacitance, flat temperature characteristics, and excellent reliability due to limitations in dielectric layer composition and thickness, which affect their performance and durability.
Innovation Solution
The design incorporates a multilayer ceramic capacitor structure with dielectric layers containing particles with voids, a core-shell structure, and specific compositions of perovskite oxides, along with optimized layer thickness and electrode configurations to enhance permittivity, temperature stability, and reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the permittivity is increased by adjusting the composition of the main component of the dielectric layer, then the capacitance is increased, but the temperature change increases and capacitance temperature characteristics deteriorate
Solution Approach 1:
The patent applies parameter changes by precisely controlling the composition ratios of multiple oxide components (BaO: 40-60 wt%, TiO2: 20-40 wt%, ZrO2: 5-15 wt%, SiO2: 3-7 wt%, Al2O3: 2-5 wt%) to achieve a permittivity of 2000 or more while maintaining capacitance temperature characteristics within ±10% from 0°C to 70°C. This compositional parameter optimization resolves the contradiction between high permittivity and temperature stability.
2Quantity of substance
If the dielectric layer is made thinner, then the capacitance is increased, but the insulation resistance life is shortened and reliability deteriorates
Solution Approach 1:
The patent uses composite materials by combining multiple oxide components (barium titanate-based main component with zirconium oxide, silicon oxide, and aluminum oxide as additives) to create a dielectric layer that achieves high capacitance with thin thickness while maintaining excellent insulation resistance and reliability through synergistic material properties.
Solution Approach 2:
The patent introduces controlled porosity with a porosity ratio of 0.1 to 0.4 to create particles with voids that enhance permittivity and capacitance while maintaining adequate insulation resistance life, resolving the contradiction between thin dielectric layer requirements and reliability.
3Quantity of substance
If the permittivity is increased, then the capacitance is increased, but the size reduction is limited due to reliability constraints
Solution Approach 1:
The patent utilizes porous materials with controlled voids and bubbles (porosity ratio 0.1-0.4) within the dielectric layer to significantly enhance permittivity and capacitance density, enabling high capacitance values in smaller capacitor sizes while maintaining reliability through optimized pore structure and composition.
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 results in capacitors with high permittivity, increased capacitance, flat temperature characteristics, and improved reliability, as demonstrated by the presence of particles with voids and specific sub-component distributions, leading to enhanced performance and longer lifespan.
Implementation Method 1
a dielectric layer at a center or an approximate center of the inner layer portion in the thickness direction includes particles having voids as the dielectric particles
Data Source
AI summary
A multilayer ceramic capacitor includes a multilayer body including first and second main surfaces opposite to each other in a thickness direction, first and second side surfaces opposite to each other in a width direction, and first and second end surfaces opposite to each other in a length direction, the multilayer body including dielectric layers and inner electrode layers laminated in the thickness direction, and a pair of outer electrodes on the first and second end surfaces and connected to the inner electrode layers. The dielectric layers include dielectric particles. The multilayer body includes a layered first side portion, a layered second side portion, a first outer layer portion, a second outer layer portion, and an inner layer portion.