Plating Process Membrane Flow to Prevent Gas Bubble Accumulation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Gas bubbles accumulating on the lower surface of the membrane in a cup type plating apparatus can deteriorate the plating quality of the substrate.

Innovation Solution

A plating process method that involves supplying anode liquid to a first region separated by a membrane, guiding it to a second region below the membrane to reduce gas bubble concentration, and discharging the liquid from both regions, while electroplating the substrate with metal.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If gas bubbles are generated in the anode chamber, then electroplating can proceed, but gas bubbles accumulate on the lower surface of the membrane and deteriorate plating quality

Engineering Contradiction:

Improveelectroplating processVSAvoidplating quality

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

The anode chamber is divided into a first region (above the membrane) and a second region (below the membrane) using the membrane as a boundary. This segmentation allows different gas bubble concentrations in different regions, with the second region having lower gas bubble concentration to prevent accumulation on the membrane surface and maintain plating quality.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The membrane acts as an intermediary element that separates the anode chamber into two regions with different gas bubble concentrations. It allows ion species to pass through while suppressing nonionic plating additives, and creates a gradient that prevents gas bubble accumulation on its lower surface.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If the membrane is used to separate anode and cathode chambers, then nonionic plating additives are suppressed from passing through, but gas bubbles accumulate on the lower surface of the membrane

Engineering Contradiction:

Improvemembrane separation functionVSAvoidgas bubble accumulation

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The membrane creates different local conditions in the two regions it separates. The first region (above) has higher gas bubble concentration from electroplating reactions, while the second region (below) has lower gas bubble concentration. This local quality difference prevents gas bubbles from accumulating on the membrane's lower surface, maintaining its separation function while eliminating the harmful accumulation effect.

Inventive Principle:

Principle #3Local quality

3Manufacturing precision

If anode liquid is supplied to the first region and then guided to the second region, then gas bubble concentration is reduced below the membrane, but the process complexity increases

Engineering Contradiction:

Improvegas bubble concentration controlVSAvoidanode liquid flow control

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The anode liquid flow is made continuous, moving from the first region through the membrane to the second region. This continuous flow ensures that gas bubbles are constantly carried away from the membrane's lower surface, preventing accumulation. The useful action of electroplating continues uninterrupted while maintaining low gas bubble concentration in the second region.

Inventive Principle:

Principle #20Continuity of useful action

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

Suppresses the accumulation of gas bubbles on the membrane surface, thereby maintaining the plating quality of the substrate by reducing gas bubble concentration in the anode liquid.

Implementation Method 1

a membrane configured to suppress passing of a nonionic plating additive contained in the plating solution while permitting passing of ion species (ion species containing metallic ions) contained in the plating solution

Methodology Applied

Scientific EffectIon Exchange: Ion Exchange

Implementation Method 2

the gas bubbles generated in the anode chamber are moved along a lower surface of the inclined site of the second membrane using buoyancy and can be moved to an outer edge of the inclined site of the second membrane

Methodology Applied

Scientific EffectBuoyancy: Archimedes' Principle (Buoyancy)

Implementation Method 3

a step of flowing electricity between the substrate and the anode to electroplate the metal on the substrate

Methodology Applied

Scientific EffectElectroplating: Electroplating

Data Source

PatentUS12351932B2Plating process method

Publication Date: 2025.07.08 EBARA CORP

AI summary

Provided is a technique that ensures suppressing deterioration of a plating quality of a substrate caused by gas bubbles accumulating on an entire lower surface of a membrane.A plating process method includes a step of guiding an anode liquid to a second region R2 positioned below a membrane 40 and above a first region R1 to decrease a concentration of gas bubbles contained in the anode liquid in the second region below a concentration of gas bubbles contained in the anode liquid in the first region; a step of discharging the anode liquid from the first region; a step of discharging the anode liquid from the second region; a step of supplying a cathode liquid to a cathode chamber 12 in which a substrate Wf is disposed; and a step of flowing electricity between the substrate Wf and an anode 13 to electroplate a metal on the substrate.