Moveable Edge Ring Tuning for Etch Uniformity and Plasma Sealing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing substrate processing systems face challenges in maintaining etch uniformity and preventing plasma leakage due to variations in edge ring configurations and erosion, which affect gas flow patterns and substrate support integrity.
Innovation Solution
Implementing moveable and replaceable edge rings with adjustable heights and labyrinthine interfaces to control gas velocity profiles and minimize plasma leakage, using actuators and lift pins for precise positioning and erosion compensation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the edge ring is made fixed and rigid, then the structural integrity is maintained, but the ability to compensate for erosion and maintain etch uniformity is lost
Solution Approach 1:
The edge ring is designed to be moveable relative to the substrate support, allowing it to be repositioned vertically. This dynamic configuration enables the edge ring to compensate for erosion over time by adjusting its position, thereby maintaining etch uniformity without compromising structural integrity during operation.
Solution Approach 2:
The vertical position of the edge ring can be adjusted to change the pocket depth parameter. By modifying this parameter, the system compensates for erosion effects and maintains optimal etch uniformity throughout the edge ring's service life.
2Manufacturing precision
If the edge ring is made moveable for tuning, then etch uniformity can be maintained, but the device complexity increases
Solution Approach 1:
The edge ring incorporates a moveable design with lift pins and guide features that enable vertical adjustment. This dynamic mechanism allows for precise positioning to maintain etch uniformity while keeping the overall structure relatively simple through straightforward mechanical components.
Solution Approach 2:
The edge ring can be repositioned using the lift pin mechanism to compensate for erosion, allowing the system to self-adjust and maintain performance without requiring complex automated control systems or multiple replacement components.
3Ease of manufacture
If the edge ring interface is simplified, then the manufacturing is easier, but plasma leakage increases
Solution Approach 1:
The interface between the edge ring and substrate support is segmented into multiple features including an annular groove, guide features, and labyrinthine structures. This segmentation creates multiple barriers to plasma leakage while maintaining manufacturability through standard machining operations.
Solution Approach 2:
The edge ring interface employs nested structural features where the annular groove receives a guide feature that extends upward from the substrate support. This nested configuration creates overlapping barriers that effectively prevent plasma leakage while being manufacturable using conventional techniques.
Data Source
AI summary
An edge ring is configured to be raised and lowered relative to a substrate support, via one or more lift pins, in a substrate processing system. The edge ring is further configured to interface with a guide feature extending upward from a bottom ring and/or a middle ring of the substrate support during tuning of the edge ring. The edge ring includes an upper surface, an annular inner diameter, an annular outer diameter, a lower surface, and an annular groove arranged in the lower surface of the edge ring to interface with the guide feature. A depth of the annular groove is selected according to a tunable range of the edge ring.