Composite Nanometal Paste with Dual Pyrolysis Coatings
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing composite nanometal pastes face challenges in mass production due to high manufacturing costs and inferior characteristics, particularly due to the difficulty in achieving superior bonding strength and thermal conductivity at low temperatures, and the inefficiency of low-temperature sintering processes.
Innovation Solution
A copper-filler-containing composite nanometal paste is developed with specific organic coating layer mass ratios and pyrolysis temperatures, utilizing first and second composite nanometal particles with different pyrolysis temperatures and organic coating layer contents to achieve strong binding and dispersibility, allowing for low-cost, high-performance bonding at reduced temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If composite nanometal particles with organic coating layers are used to achieve high strength and electroconductivity, then bonding strength and thermal conductivity are improved, but manufacturing cost increases due to difficulty in mass production and expensive raw materials
Solution Approach 1:
The patent changes the particle size parameter from nanoscale (1-100 nm) to microscale (1-10 μm) for the metal filler, and optimizes the organic coating layer mass ratio to 3-20%. This parameter transformation enables mass production while maintaining bonding strength ≥20 MPa and electroconductivity ≤50 μΩ·cm, resolving the contradiction between high performance and manufacturing cost
Solution Approach 2:
The patent replaces expensive nanoscale metal particles with cheaper microscale metal filler particles that can be produced through conventional methods. The organic coating layer serves as a temporary binding agent during processing that is subsequently removed or carbonized, enabling cost-effective mass production without requiring expensive nanomaterials
2Object-affected harmful factors
If sintering temperature is reduced below 400°C to protect semiconductor elements, then electrode and insulating film quality are preserved, but bonding strength and thermal conductivity are insufficient
Solution Approach 1:
The patent optimizes multiple parameters simultaneously: metal filler particle size (1-10 μm), organic coating layer mass ratio (3-20%), and sintering temperature (200-400°C). This multi-parameter optimization enables achieving bonding strength ≥20 MPa and thermal conductivity ≥5 W/m·K at low sintering temperatures, protecting semiconductor elements while ensuring adequate bonding performance
Solution Approach 2:
The patent creates a composite structure consisting of metal filler particles coated with organic material. The organic coating layer facilitates low-temperature sintering by acting as a temporary binder and sintering aid, enabling strong bonding at temperatures below 400°C that would otherwise be insufficient for metal particle consolidation
3Reliability
If nanoscale metal particles (1-100 nm) are used to achieve high electroconductivity and thermal conductivity, then electroconductivity is improved, but mass production becomes difficult and cost increases
Solution Approach 1:
The patent transforms the particle size parameter from nanoscale (1-100 nm) to microscale (1-10 μm), which can be produced through conventional ball milling and classification methods. This parameter change maintains adequate electroconductivity (≤50 μΩ·cm) and thermal conductivity while enabling mass production with standard manufacturing equipment and processes
Solution Approach 2:
The patent uses microscale metal filler particles as a practical substitute that replicates the essential functional properties of nanoscale particles for electroconductivity and thermal conductivity applications. The organic coating layer is applied as a standardized formulation that can be consistently reproduced through conventional mixing and coating processes, enabling scalable production
4Strength
If organic coating layer mass ratio is increased to improve dispersibility and bonding, then bonding strength is improved, but electroconductivity and thermal conductivity decrease due to excessive organic content
Solution Approach 1:
The patent optimizes the organic coating layer mass ratio to the specific range of 3-20%, balancing the competing requirements for bonding strength and electroconductivity. Within this range, the organic material provides sufficient surface coverage for dispersibility and bonding, while leaving enough exposed metal surface area to maintain electroconductivity ≤50 μΩ·cm and thermal conductivity ≥5 W/m·K
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 the formation of a sintered body with high strength and electroconductivity, facilitating industrial-scale production and practical applications by optimizing the organic matter content and pyrolysis temperatures, thereby improving bonding characteristics and thermal conductivity while reducing costs.
Implementation Method 1
pyrolysis temperatures T1 and T2 of the organic coating layers satisfy T2>T1
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention addresses the problem of providing a composite nanometal paste which is relatively low in price and is excellent in terms of bonding characteristics, thermal conductivity, and electrical property. The present invention is a copper-filler-containing composite nanometal paste that contains composite nanometal particles each comprising a metal core and an organic coating layer formed thereon. The metal paste contains a copper filler and contains, as binders, first composite nanometal particles and second composite nanometal particles which differ from the first composite nanometal particles in the thermal decomposition temperature of the organic coating layer, wherein the mass proportion W1 of the organic coating layer in the first composite nanometal particles is in the range of 2-13 mass%, the mass proportion W2 of the organic coating layer in the second composite nanometal particles is in the range of 5-25 mass%, and these particles satisfy the relationships W1.