Silver Electroconductive Adhesive for Pressureless Low-Temperature Sintering

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing electroconductive adhesives face challenges in forming a sintered body with high denseness and mechanical strength without pressurization during sintering, leading to issues like voids, cracking, and chipping, especially when applied to complex structures, and require sintering at lower temperatures to avoid damage and equipment complexity.

Innovation Solution

An electroconductive adhesive containing silver particles with an average size of 20 nm to 500 nm and a solvent with a moisture content of 1300 ppm or less, which allows sintering at 200°C to 250°C without pressurization, ensuring high denseness and mechanical strength by controlling moisture absorption and enhancing necking between particles.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If pressurization is applied during sintering to increase denseness, then voids are reduced and mechanical strength is improved, but equipment complexity increases and damage may occur to the member

Engineering Contradiction:

Improvedenseness of sintered bodyVSAvoidequipment complexity

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The invention changes the chemical composition parameters of the electroconductive adhesive by specifying silver particle size distribution (30% or more with 100-200 nm diameter) and using amine compound protective agents, enabling sintering without pressurization while achieving high denseness

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention replaces the mechanical pressurization system with a chemical composition-based solution, where the specific silver particle characteristics and amine compound protective agent enable self-sintering at low temperatures without requiring pressurization equipment

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Device complexity

If sintering temperature is reduced to avoid damage and simplify equipment, then equipment complexity is reduced, but voids and cracking may occur in the sintered body

Engineering Contradiction:

Improveequipment complexityVSAvoidquality of sintered body

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The invention changes the chemical parameters by using amine compound protective agents on silver particles, which enable low-temperature sintering (200-250°C) while maintaining sintered body quality without voids or cracking

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention creates a composite system combining silver particles with specific size distribution and amine compound protective agents, which together enable low-temperature sintering while preventing defects in the sintered body

Inventive Principle:

Principle #40Composite materials

3Strength

If epoxy resin is used to suppress voids and improve joining strength, then mechanical strength is improved, but electroconductivity and thermal conductivity are reduced

Engineering Contradiction:

Improvejoining strengthVSAvoidelectroconductivity

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

The invention extracts and removes the epoxy resin component from the electroconductive adhesive, relying solely on sintered silver particles bonded with amine compound protective agents to achieve both high mechanical strength and high electroconductivity

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The invention uses a composite of silver particles and amine compound protective agents without epoxy resin, achieving a balance of mechanical strength, electroconductivity, and thermal conductivity

Inventive Principle:

Principle #40Composite materials

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

The adhesive forms a sintered body with high denseness and mechanical strength, minimizing defects like cracking and voids, while enabling efficient low-temperature sintering without pressurization, thus improving reliability and reducing equipment requirements.

Implementation Method 1

silver particles have a feature of being easily sintered by a heat treatment at a low temperature for a short time

Methodology Applied

Scientific EffectSintering: Sintering

Implementation Method 2

a sintered body having low resistance and a sintered body having excellent thermal conductivity can be formed

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 3

silver particles have a feature of being easily sintered by a heat treatment at a low temperature for a short time... a sintered body having low resistance

Methodology Applied

Scientific EffectElectrical conduction: Conduction (electrical)

Data Source

PatentUS12441917B2Electroconductive adhesive

Publication Date: 2025.10.14 OSAKA SODA CO LTD

AI summary

The present invention provides an electroconductive adhesive which is desirably sintered at low temperatures even without pressurization during the sintering of the electroconductive adhesive, and which forms a sintered body that has high denseness and high mechanical strength (shear strength) if used as an electroconductive adhesive. An electroconductive adhesive which contains a solvent and silver particles that have an average particle diameter within the range of from 20 nm (inclusive) to 500 nm (exclusive), wherein the moisture content in the electroconductive adhesive is 1,300 ppm or less.