Electroplating Recirculation Vessel for Reduced Air Entrainment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electroplating systems in semiconductor fabrication face challenges with air entrainment in processing fluids, leading to defects and device failures due to bubbles lodging in substrate features, which conventional control methods like valves and debubblers are insufficient to address effectively.
Innovation Solution
The system incorporates a recirculating tank with a delivery pump, a vessel having an inner and outer chamber, a return line with a restriction, and a return pump with an integral-level control algorithm, along with a media configured to extract bubbles, to manage fluid levels and reduce air entrainment, using a buffer vessel and standpipes to control fluid flow and remove bubbles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional valves and debubblers are used to control air entrainment, then device complexity increases, but air removal effectiveness remains insufficient
Solution Approach 1:
The patent extracts air bubbles from the processing fluid by introducing a gas-permeable membrane that selectively removes gas phases while allowing liquid to pass through. This extraction approach directly addresses the insufficient air removal effectiveness without requiring complex valve and debubbler systems, thereby improving reliability while avoiding increased device complexity
Solution Approach 2:
The gas-permeable membrane acts as an intermediary component between the processing fluid and the atmosphere, enabling selective gas removal. This mediator approach provides effective air removal through a simple, elegant solution that avoids the complexity of conventional multi-component valve and debubbler systems
2Ease of operation
If fluid level control is loosened to simplify operation, then ease of operation improves, but air entrainment increases
Solution Approach 1:
The system implements self-service fluid level control through a reservoir that automatically maintains appropriate levels. The reservoir design allows the system to self-regulate fluid levels without requiring complex control mechanisms or frequent manual intervention, thereby maintaining ease of operation while preventing air entrainment through proper level management
Solution Approach 2:
The patent incorporates a reservoir that provides a buffer or cushion of fluid before the main processing chamber. This beforehand cushioning ensures that fluid levels remain stable and adequate even during operation, preventing air from being drawn into the system while keeping the control system simple and easy to operate
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 solution effectively reduces air entrainment in processing fluids, minimizing defects and device failures by providing precise control over fluid levels and bubble removal, suitable for semiconductor fabrication and potentially applicable to other small-scale fluid processing technologies.
Implementation Method 1
A liquid level sensor may be associated with the vessel to provide a liquid level indication in the outer chamber
Implementation Method 2
The return line may include a restriction sized to maintain a gravity-assisted fluid flow rate less than a steady-state delivery rate of the delivery pump
Implementation Method 3
The container may be configured to receive processing fluid exiting the vessel. The container may include a media configured to extract entrained bubbles within the processing fluid
Data Source
AI summary
Electroplating processing systems according to the present technology may include a recirculating tank containing a first volume of processing fluid. The recirculating tank may be fluidly coupled with a delivery pump. The systems may include a vessel configured to receive the processing fluid from the pump. The vessel may include an inner chamber and an outer chamber, and the inner chamber may be sized to hold a second volume of processing fluid less than the first volume of processing fluid. A liquid level sensor may be associated with the vessel to provide a liquid level indication in the outer chamber. The systems may include a return line coupled with an outlet of the vessel and coupled with an inlet of the recirculating tank. The systems may also include a return pump fluidly coupled with the return line. The return pump may be electrically coupled with the liquid level sensor.