Electroplating Leveling Agent for Uniform Through-Hole Copper Filling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing copper electroplating technologies face challenges in achieving uniform filling of through holes with different apertures, maintaining a low dimple value, and ensuring high electroplating uniformity, which are crucial for manufacturing reliable and high-density interconnected electronic substrates.
Innovation Solution
The use of a specific electroplated composition that includes a leveling agent with a nitrogen-containing heterocyclic group connected via sulfur bonds to an ether oxygen chain, which selectively adsorbs in areas of high current density, adjusts current density distribution, and suppresses metal deposition, thereby facilitating uniform metal plating and filling of through holes with varying apertures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional electroplating formulas are used, then electroplating can be performed, but uniform filling of through holes with different apertures cannot be achieved and dimple value remains high
Solution Approach 1:
The patent modifies the chemical parameters of the electroplating solution by introducing a specific leveling agent with nitrogen-containing heterocyclic groups and ether oxygen chains. This additive changes the electrochemical parameters at the cathode surface, enabling selective adsorption in high current density areas and achieving uniform deposition across through holes of different apertures while maintaining low dimple values
Solution Approach 2:
The leveling agent acts as an intermediary substance between the electroplating solution and the substrate surface. It mediates the deposition process by selectively adsorbing on the cathode surface in high current density regions, regulating metal ion reduction, and ensuring uniform filling of through holes with varying apertures, thereby improving both electroplating uniformity and interconnection reliability
2Manufacturing precision
If copper plating thickness is increased to ensure filling, then hole filling rate improves, but surface metal layer thickness increases and fine line formation becomes difficult
Solution Approach 1:
The leveling agent provides local quality control by selectively adsorbing on the cathode surface in high current density areas (such as the bottom of through holes), while having minimal effect in low current density areas (such as flat surfaces). This localized action enables complete hole filling without excessive metal deposition on the surface, maintaining thin surface layers suitable for fine line formation
Solution Approach 2:
The patent changes the deposition parameters through the leveling agent, which modifies the local electrochemical environment at the cathode surface. This enables differentiation between hole filling regions and surface regions, achieving high hole filling rates while controlling surface metal thickness to facilitate fine line manufacturing
3Manufacturing precision
If electroplating time is extended to improve filling, then hole filling rate increases, but production efficiency decreases
Solution Approach 1:
The leveling agent as an intermediary substance accelerates the hole filling process by selectively concentrating metal deposition in through hole regions. This mediator enables rapid and uniform filling of holes with different apertures, achieving high hole filling rates in reduced time, thereby improving production efficiency without sacrificing filling quality
4Manufacturing precision
If conventional leveling agents are used, then some leveling effect is achieved, but simultaneous filling of through holes with different apertures cannot be implemented
Solution Approach 1:
The leveling agent exhibits universal effectiveness across through holes of different apertures (small holes with high aspect ratios and large holes). The nitrogen-containing heterocyclic groups and ether oxygen chains enable the additive to adapt to various hole geometries, providing simultaneous uniform filling capability for diverse aperture sizes, thus achieving multi-functional performance in a single electroplating 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 enables simultaneous filling of through holes with different apertures, reduces the thickness of the surface metal layer and dimple value, and improves electroplating uniformity, enhancing the reliability and manufacturing efficiency of electronic products.
Implementation Method 1
the leveling agent can be selectively adsorbed in an area with high current density, current density distribution on a cathode surface in an electroplating process is better adjusted
Implementation Method 2
metal deposition in an area corresponding to high current density can be effectively suppressed, to obtain a uniform metal plated layer
Data Source
AI summary
A composition is provided. The composition includes a metal ion source and a leveling agent shown in Formula (I): R1—S—(R3—O)m—(R2—O)n—R2—(O—R3)m—S—R1. In Formula (I), two pieces of R1 are independently selected from a substituted or unsubstituted nitrogen-containing heterocyclic group, two pieces of R2 are independently substituted or unsubstituted chain alkylene, two pieces of R3 are independently substituted or unsubstituted chain alkylene, m is 0 or 1, and n is an integer greater than or equal to 2. The composition is applied to metal filling of a through hole on an electronic substrate, to uniformly fill through holes with different apertures, and lower a thickness of a surface metal layer and a dimple value.