MLCC External Electrodes With Glass Layers for Thin-End Reliability

Solution Overview

Problem

The decreasing thickness of external electrodes in multilayer ceramic capacitors (MLCCs) makes them more susceptible to moisture and plating solution permeation, reducing the reliability of the components.

Innovation Solution

The use of a multilayer electronic component design featuring external electrodes with Ag-based lower electrode layers and Cu-based upper electrode layers, both embedded with glass layers, to prevent moisture and plating solution ingress.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the thickness of the external electrode is decreased to increase capacitance per unit volume, then the capacitance per unit volume is improved, but the reliability deteriorates due to easier permeation of external moisture or plating solution into the body

Engineering Contradiction:

Improvecapacitance per unit volumeVSAvoidreliability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The external electrode is segmented into multiple layers (first external electrode layer, second external electrode layer, third external electrode layer) with different materials and functions. The first layer provides moisture barrier function, the second layer provides plating solution barrier function, and the third layer provides electrical connection function, allowing each layer to specialize in preventing specific types of permeation while maintaining overall electrode functionality

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The external electrode uses composite material structure with different metal layers (e.g., Cu-based first layer, Ag-based second layer, Ni-based third layer) and glass layers. Each material is selected for its specific properties: Cu for conductivity and moisture resistance, Ag for plating solution resistance, Ni for oxidation resistance, and glass for sealing, creating a composite structure that collectively prevents both moisture and plating solution permeation

Inventive Principle:

Principle #40Composite materials

2Productivity

If the thickness of the external electrode is decreased to improve capacitance per unit volume, then the capacitance per unit volume is improved, but the protection against harmful factors deteriorates

Engineering Contradiction:

Improvecapacitance per unit volumeVSAvoidmoisture and plating solution permeation

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The external electrode is segmented into multiple layers (first external electrode layer, second external electrode layer, third external electrode layer) with different materials and functions. The first layer provides moisture barrier function, the second layer provides plating solution barrier function, and the third layer provides electrical connection function, allowing each layer to specialize in preventing specific types of permeation while maintaining overall electrode functionality

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The external electrode uses composite material structure with different metal layers (e.g., Cu-based first layer, Ag-based second layer, Ni-based third layer) and glass layers. Each material is selected for its specific properties: Cu for conductivity and moisture resistance, Ag for plating solution resistance, Ni for oxidation resistance, and glass for sealing, creating a composite structure that collectively prevents both moisture and plating solution permeation

Inventive Principle:

Principle #40Composite materials

Data Source

PatentUS20250125097A1Multilayer electronic component

Publication Date: 2025.04.17 SAMSUNG ELECTRO MECHANICS CO LTD

AI summary

A multilayer electronic component includes a body including a dielectric layer and first and second internal electrodes, the body having a first surface and a second surface opposing each other in a first direction, a third surface and a fourth surface opposing each other in a second direction, and a fifth surface and a sixth surface opposing each other in a third direction, an external electrode including a lower electrode layer, the lower electrode layer disposed between extension lines of the first and second surfaces, an upper electrode layer disposed on the lower electrode layer, the upper electrode layer disposed to extend onto a portion of the first and the second surfaces, and a glass layer disposed between the lower and upper electrode layers. The lower electrode layer includes Ag and a first glass. The upper electrode layer includes Cu and a second glass.