Low-Temperature Bonding Material Using Coated Metal Nanoparticles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional bonding technologies using metal particles with a particle size of 100 nm or less face challenges in achieving high heat dissipation and reliability due to aggregation and require high temperatures for complete decomposition of organic coatings, which can damage electronic parts and reduce shear strength.
Innovation Solution
A bonding material comprising metal particles with a particle size of 100 nm or less and larger particles up to 100 μm, coated with organic substances containing 2 to 8 carbon atoms, which allows for lower decomposition temperatures and improved dispersibility, enhancing shear strength through sintering at lower temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If metal particles with particle size of 100 nm or less are used for bonding, then high heat dissipation and heat resistance are achieved, but aggregation occurs and high temperature is required for complete decomposition of organic coating
Solution Approach 1:
The patent changes the chemical composition parameter of the organic coating from conventional materials to specific carboxylic acids with 2-8 carbon atoms (formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, capric acid). This parameter change enables the organic coating to decompose at lower temperatures (200-400°C) while maintaining effective sintering of metal particles, thus resolving the contradiction between achieving heat resistance and avoiding high bonding temperatures that damage electronic parts.
2Loss of energy
If metal particles with particle size of 100 nm or less are used for bonding, then high heat dissipation is achieved, but aggregation occurs reducing dispersibility
Solution Approach 1:
The patent introduces organic coating materials (specific carboxylic acids with 2-8 carbon atoms) as intermediaries on the surface of metal particles. These intermediaries prevent direct contact and aggregation between metal particles while maintaining their small size (100 nm or less), thereby preserving heat dissipation properties. The organic coating acts as a spacer and protective layer that ensures stable dispersibility in the bonding material without compromising the thermal performance of the fine metal particles.
3Reliability
If high temperature is used for bonding to decompose organic coating, then complete decomposition is achieved, but electronic parts are damaged
Solution Approach 1:
The patent changes the thermal decomposition parameter of the organic coating by selecting carboxylic acids with 2-8 carbon atoms. These specific compounds decompose at lower temperatures (200-400°C) compared to conventional organic coatings. This parameter change allows complete decomposition of the organic coating at temperatures that do not damage sensitive electronic parts, thereby achieving bonding reliability without thermal damage.
4Reliability
If conventional organic coatings are used on metal particles, then high temperature decomposition is achieved, but shear strength is reduced
Solution Approach 1:
The patent changes the molecular structure parameter of the organic coating to specific carboxylic acids with 2-8 carbon atoms. This parameter change enables decomposition at lower temperatures that preserve the integrity of the bonding interface. The lower decomposition temperature prevents excessive thermal softening or degradation of the bonding material matrix, thereby maintaining higher shear strength while achieving complete decomposition of the organic coating.
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 solution enables low-temperature, short-time bonding with increased shear strength and improved reliability, reducing the risk of electronic part damage while maintaining high heat dissipation and long-term reliability.
Implementation Method 1
the organic substance covering the metal particles is decomposed at the time of heating and pressurizing to thereby effect sintering phenomenon among the metal particles
Implementation Method 2
the organic substance covering the metal particles is decomposed at the time of heating and pressurizing
Implementation Method 3
a bonding material which is excellent in high heat dissipation and heat resistance is needed
Data Source
AI summary
A bonding material comprising metal particles coated with an organic substance having carbon atoms of 2 to 8, wherein the metal particles comprises first portion of 100 nm or less, and a second portion larger than 100 nm but not larger than 100 μm, each of the portions having at least peak of a particle distribution, based on a volumetric base. The disclosure is further concerned with a bonding method using the bonding material.