Copper Paste Composition for Oxidation-Resistant Sintered Joining
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current bonding materials for semiconductor and LED devices face challenges with high thermal conductivity, oxidation resistance, and reliability due to atmospheric exposure, especially when used in high-temperature and high-current applications, leading to potential peeling and reduced performance.
Innovation Solution
A paste composition is developed using copper particles coated with an amine compound and carboxylic acid amine salt, with a total content of these compounds less than 1 mass%, which maintains high sinterability and joinability while preventing oxidation, ensuring reliable bonding in semiconductor, electrical, and electronic components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If copper particles are used as joining material, then thermal conductivity and cost are improved, but oxidation resistance deteriorates due to atmospheric exposure
Solution Approach 1:
The patent uses composite copper particles consisting of a copper core surrounded by a protective shell made of copper oxide and copper hydroxide. This composite structure combines the high thermal conductivity of metallic copper with the oxidation resistance of the oxide/hydroxide shell, resolving the contradiction between thermal performance and oxidation protection.
Solution Approach 2:
The copper particles are treated to create an inert protective environment around the reactive copper core. The oxide and hydroxide layers act as a barrier that prevents atmospheric oxygen from reaching and oxidizing the metallic copper, effectively creating a protected micro-environment that maintains both conductivity and oxidation resistance.
2Ease of manufacture
If adhesive is used for joining light-emitting element and substrate, then joining is achieved, but peeling occurs at solder melting temperature during mounting
Solution Approach 1:
The patent replaces the organic adhesive with a inorganic paste composition that can withstand high temperatures. The paste is designed to be applied in a controlled manner and then sintered to form a permanent, heat-resistant bond that eliminates the peeling issue during solder mounting processes.
Solution Approach 2:
The invention changes the fundamental parameters of the joining material from organic adhesive to inorganic paste composition. This parameter change enables the joining material to withstand solder melting temperatures without degrading or peeling, while still providing effective joining capability through controlled application and sintering processes.
3Temperature
If silver nanoparticles are used for joining, then thermal conductivity and joinability are improved, but cost increases and migration difficulties occur
Solution Approach 1:
The patent replaces expensive silver nanoparticles with copper-based particles that provide comparable thermal conductivity. The copper particles are significantly cheaper and can be processed using standard sintering techniques, eliminating the need for expensive silver materials while maintaining joining performance.
Solution Approach 2:
The invention changes the material composition from silver-based to copper-based particles, fundamentally altering the cost parameter while maintaining thermal conductivity through optimized particle morphology and surface treatment. The paste composition is formulated to enable effective sintering of copper particles to achieve desired thermal and mechanical properties.
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 paste composition effectively maintains high sinterability and joinability without being affected by atmospheric exposure time, providing improved reliability and oxidation resistance for semiconductor, electrical, and electronic components, especially in high-temperature applications.
Implementation Method 1
the first copper particles are formed by covering copper particles serving as a base material with at least one compound selected from the group consisting of an amine compound (a) and a carboxylic acid amine salt (b)... providing improved reliability and oxidation resistance
Implementation Method 2
a joining material having long-term and high-temperature heat resistance in addition to electrical conductivity and thermal conductivity is required
Implementation Method 3
a joining method using silver nanoparticles has been attracting attention, which enables joining at a temperature lower than that of bulk silver... A paste composition including first copper particles... maintains high sinterability
Data Source
AI summary
A paste composition including first copper particles, wherein the first copper particles are formed by covering copper particles serving as a base material with at least one type of compound selected from the group consisting of an amine compound (a) and a carboxylic acid amine salt (b), and a total content of the amine compound (a) and the carboxylic acid amine salt (b) detected in the paste composition is less than 1 mass % of an entire amount of the paste composition.