Moveable Edge Ring Height Control for Plasma Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing substrate processing systems face issues with edge ring wear due to plasma exposure, leading to non-uniformity in plasma treatment and the need for frequent chamber openings for replacement, which increases downtime and costs.
Innovation Solution
A moveable edge ring system with a top moveable ring, a moveable support ring, and a shield ring, adjusted by an actuator and lift pin, maintains consistent capacitive coupling and RF voltage despite wear, allowing for in-situ height adjustment without breaking vacuum.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the edge ring is made stationary to maintain plasma uniformity, then plasma uniformity is improved, but the edge ring wears out and requires frequent replacement, increasing downtime and costs
Solution Approach 1:
The edge ring is made moveable rather than stationary, allowing it to be adjusted vertically by an actuator mechanism. This enables the edge ring to maintain its functional position relative to the substrate despite wear, converting a static component into a dynamic one that can adapt over time
Solution Approach 2:
The vertical position parameter of the edge ring is made adjustable through the actuator mechanism. By changing the position parameter vertically, the system compensates for wear-induced thickness reduction, maintaining the edge ring's effective height and plasma-shaping function throughout its service life
2Reliability
If the edge ring position is fixed to ensure consistent capacitive coupling, then capacitive coupling consistency is improved, but wear changes the edge ring effect on plasma, adversely affecting uniformity
Solution Approach 1:
The system incorporates a feedback mechanism where the actuator adjusts the edge ring position based on detected wear or performance degradation. This closed-loop control maintains the edge ring at the optimal vertical position, ensuring consistent capacitive coupling and plasma uniformity throughout operation
Solution Approach 2:
The edge ring system performs self-adjustment through the actuator mechanism, automatically compensating for wear without requiring external intervention or chamber opening. The system serves itself by maintaining its own functional integrity over time
3Manufacturing precision
If the edge ring is replaced frequently to maintain performance, then plasma uniformity is improved, but chamber openings increase downtime and operational costs
Solution Approach 1:
The moveable edge ring with actuator adjustment eliminates the need for frequent replacements by dynamically compensating for wear in-situ, allowing continuous operation without chamber openings and maintaining high productivity
Solution Approach 2:
The actuator mechanism performs preliminary adjustment to compensate for wear before it significantly degrades plasma uniformity. By proactively maintaining the edge ring position, the system prevents performance degradation rather than reacting to it
4Duration of action of stationary object
If the edge ring height is adjusted to compensate for wear, then service life is extended, but the system complexity increases with actuators and lift pins
Solution Approach 1:
The adjustment function is segmented into discrete components (actuator, lift pin, moveable support ring) that work independently but coordinate together. This modular segmentation makes the complex adjustment mechanism more manageable and maintainable
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
The system reduces plasma non-uniformities and extends the time between edge ring replacements, minimizing downtime and costs by compensating for wear through geometric height variation.
Implementation Method 1
maintains consistent capacitive coupling and RF voltage despite wear
Implementation Method 2
Plasma may be used to ignite the gases to enhance chemical reactions. During operation, the substrate and an exposed surface of the edge ring is etched by the plasma.
Data Source
AI summary
A moveable edge ring system for a substrate processing system includes a top moveable ring including a first annular body arranged around a substrate support. The top moveable ring is exposed to plasma during substrate processing. A moveable support ring is arranged below the top moveable ring and radially outside of a baseplate of the substrate support and includes a second annular body. A shield ring is arranged radially outside of the moveable support ring and includes a third annular body. A cover ring includes a fourth annular body arranged above a radially outer edge of the top moveable ring. An actuator and a lift pin are configured to adjust a position of the top moveable ring and the moveable support ring relative to the shield ring and the cover ring.