Continuous Copper Electroplating Bath Stabilization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In continuous copper sulfate electroplating, decomposed organic additives in the plating bath lead to reduced copper ions and poor plating film quality, as existing methods struggle to efficiently control copper ion concentration and oxidative decomposition of these additives, often resulting in plating failures due to incomplete decomposition and variations in the plating bath.
Innovation Solution
A continuous copper electroplating method using a copper sulfate plating bath with a soluble or insoluble anode and a cathode workpiece, incorporating an overflow vessel and an oxidative decomposition vessel where metallic copper is immersed to undergo air bubbling, allowing for independent oxidative decomposition of decomposed organic products, thereby maintaining plating bath quality and stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If air agitation is carried out in a separate vessel to replenish copper ions, then copper ion concentration is maintained, but decomposed organic products cannot be effectively decomposed
Solution Approach 1:
The invention divides the plating system into separate functional vessels: a plating vessel for copper electroplating and a decomposition vessel for oxidative decomposition of organic products. This segmentation allows independent control of copper ion replenishment and organic additive decomposition, resolving the contradiction between maintaining copper ion concentration and eliminating harmful decomposition products.
Solution Approach 2:
The invention extracts the decomposition function from the plating vessel and places it in a separate decomposition vessel. By taking out the oxidative decomposition process using an insoluble anode, the system can effectively remove decomposed organic products without interfering with the copper plating process, thus eliminating harmful factors while maintaining copper ion concentration.
2Object-generated harmful factors
If blank electrolysis is carried out in a separate vessel with an insoluble anode, then decomposed organic products are reduced by oxidative decomposition, but the process takes too long to be practical
Solution Approach 1:
The invention implements continuous circulation of the plating bath between the plating vessel and the decomposition vessel. The plating bath is continuously pumped from the plating vessel to the decomposition vessel for oxidative decomposition, then returned to the plating vessel. This continuous circulation ensures that decomposed organic products are constantly removed without stopping the plating process, making the decomposition process practical and time-efficient.
Solution Approach 2:
The plating bath is preliminarily treated in the decomposition vessel before being returned to the plating vessel. By performing oxidative decomposition in advance through continuous circulation, the system prevents accumulation of harmful organic products, ensuring the plating bath is always in optimal condition for high-quality copper plating.
3Object-generated harmful factors
If stronger air agitation is used to increase dissolved oxygen for oxidative decomposition, then decomposition efficiency improves, but large bubbles attach to workpieces causing plating failures
Solution Approach 1:
The invention separates the oxidative decomposition process from the plating process by using a dedicated decomposition vessel with an insoluble anode. This segmentation eliminates the need for air agitation in the plating vessel, preventing bubble attachment to workpieces while still achieving effective oxidative decomposition of organic products through electrochemical oxidation at the anode.
Solution Approach 2:
The invention replaces the mechanical air agitation system with an electrochemical oxidation system using an insoluble anode. Instead of using air bubbles to provide oxygen for oxidation, the system uses electrical current to generate oxygen at the anode surface, which then oxidizes organic products in the plating bath. This substitution eliminates the harmful effect of large bubbles attaching to workpieces while maintaining decomposition efficiency.
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 method efficiently decomposes decomposed organic products, stabilizes the plating bath composition, and ensures continuous, high-quality copper electroplating by maintaining copper ion concentration and reducing voids and deposition failures in the plating film.
Implementation Method 1
metallic copper is immersed in the plating bath in the oxidative decomposition vessel to expose the metallic copper to air bubbling whereby while dissolving the metallic copper as copper ions
Implementation Method 2
decomposed/degenerated organic products produced by decomposition or degeneration of the organic additives are subjected to oxidative decomposition treatment on the surface of the metallic copper by non-electrolytic oxidation action
Implementation Method 3
copper is continuously electroplated on a workpiece to be plated in a plating vessel accommodating a copper sulfate plating bath
Implementation Method 4
copper sulfate electroplating is carried out
Data Source
AI summary
A continuous copper electroplating method wherein copper is continuously plated on a workpiece to be placed in a plating vessel accommodating a copper sulfate plating bath containing organic additives by use of a soluble or insoluble anode and a workpiece as a cathode, the method including overflowing the plating bath from the plating vessel in an overflow vessel under which the plating bath in the overflow vessel is returned to the plating vessel, providing an oxidative decomposition vessel, and returning a plating bath from the oxidative decomposition vessel through the overflow vessel to the plating vessel to circulate the plating bath between the plating vessel and oxidative decomposition vessel, and metallic copper is immersed in the plating bath in the oxidative decomposition vessel and exposed to air bubbling, so that decomposed/degenerated organic products formed by decomposition or degeneration produced during the copper electroplating can be oxidatively decomposed.