Nitride Substrate Metal Layer Adhesion via Aluminum Surface Modification
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for manufacturing printed circuit boards with metal-containing layers face challenges such as sintering of Ti powder, leading to substrate damage, oxidation, and high costs, along with low adhesive forces between nitride substrates and metal layers, which complicates the separation and recovery of substrates and affects the quality of plating processes.
Innovation Solution
A method involving a mixture of metal powder, an anti-sintering agent, and an activator is used to form a metal-containing layer on a dielectric substrate under inert or reducing atmospheres, preventing sintering and enhancing adhesive forces, using alternatives like Al2O3, TiO2, or TiC as anti-sintering agents, and performing heat treatments to improve binding forces between layers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If Ti powder is used to surface-modify the substrate to increase adhesive force, then adhesive force between substrate and metal layer is improved, but Ti powder sintering occurs causing substrate damage and process complexity
Solution Approach 1:
The patent replaces expensive Ti powder with Al powder as the surface modification material. Al powder serves its purpose of increasing adhesive force through reaction with the nitride substrate to form an AlN layer, and unlike Ti, it does not sinter at the processing temperatures, avoiding substrate damage and simplifying the process.
Solution Approach 2:
The patent changes the material parameter from Ti to Al, and adjusts the processing temperature parameter to 600-900°C, which is below the sintering temperature of Ti but sufficient for Al to react with the nitride substrate and form a strong adhesive layer.
2Strength
If Ti powder is used for surface modification, then adhesive force is improved, but oxidation and ignition of Ti occur at high temperatures
Solution Approach 1:
The patent replaces Ti with Al, which has better oxidation resistance at the processing temperatures. Al forms a protective oxide layer that prevents further oxidation, eliminating the ignition hazard associated with Ti powder at high temperatures.
3Strength
If Ti powder is sintered on the substrate, then adhesive force is improved, but separation and recovery of substrate becomes difficult
Solution Approach 1:
The patent uses Al powder instead of Ti powder. The Al reacts with the nitride substrate to form an AlN interfacial layer that provides strong adhesive force without creating a sintered body that bonds the substrate to the powder. This allows for easy separation and recovery of the substrate after the surface modification process.
4Manufacturing precision
If Ti powder mixture is heat-treated at high temperature, then metal layer formation is achieved, but sintered body formation adversely affects subsequent plating process
Solution Approach 1:
The patent changes the material from Ti to Al, and processes at 600-900°C. This temperature range is sufficient for Al to react with the nitride substrate and form a high-quality AlN interfacial layer with good adhesion, but it is below the sintering temperature of Al, preventing formation of sintered bodies that would harm the subsequent plating process.
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
This approach effectively inhibits sintering, enhances adhesive forces, and facilitates easy separation and recovery of substrates, while reducing costs by using alternatives to expensive Ti, resulting in improved plating layer quality and process efficiency.
Implementation Method 1
forming a metal-containing layer on the surface of the dielectric substrate by heating the mixture under an inert atmosphere or under a reducing atmosphere
Implementation Method 2
preventing sintering of the Ti powder and easily separating and recovering the substrate after reaction
Implementation Method 3
performing heat treatments to improve binding forces between layers
Implementation Method 4
forming a first metal layer on the metal-containing layer by electroless plating
Implementation Method 5
forming a second metal layer thereon by electroplating
Data Source
AI summary
Provided is a method for manufacturing a circuit board including: (a) preparing a mixture of a metal powder, an anti-sintering agent, and an activator; (b) immersing a dielectric substrate in the mixture; (c) forming a metal-containing layer on the surface of the dielectric substrate by heating the mixture under an inert atmosphere or under a reducing atmosphere; (d) forming a first metal layer on the metal-containing layer by electroless plating and forming a second metal layer thereon by electroplating; and (e) forming a metal pattern on the dielectric substrate, wherein the first metal layer includes Cu, Ni, Co, Au, Pd, or an alloy thereof, the second metal layer includes Cu, Ni, Fe, Co, Cr, Zn, Au, Ag, Pt, Pd, Rh, or an alloy thereof, and the method further includes performing heat treatment at least once after step (c).