Nested Edge Ring Structure for Plasma Uniformity Without Arc Discharge
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing edge rings in plasma processing apparatuses have limited vertically movable range, leading to potential arc discharges and restricted plasma uniformity, which can result in increased maintenance costs and downtime due to frequent replacements.
Innovation Solution
An edge ring design featuring a first movable portion, a second movable portion, and a driving mechanism that allows for increased vertical movement, maintaining a closed space even when worn, preventing arc discharges and enhancing plasma distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the edge ring is raised to improve plasma uniformity, then plasma distribution is improved, but arc discharge occurs due to gap formation between the edge ring and support table
Solution Approach 1:
The patent employs a nested structure where the first movable portion is positioned within the second movable portion, creating a telescopic edge ring mechanism. This allows the edge ring to extend vertically without creating gaps, as the nested portions work together to maintain continuous contact with the support table while achieving the desired height adjustment for plasma uniformity.
Solution Approach 2:
The edge ring is divided into multiple segments: a stationary portion, a first movable portion, and a second movable portion. Each segment can move independently or in coordination, allowing the overall structure to achieve vertical adjustment while maintaining gap-free contact through the coordinated movement of segmented components.
2Reliability
If the edge ring movable range is limited to prevent arc discharge, then reliability is maintained, but plasma uniformity cannot be optimized
Solution Approach 1:
The nested configuration of the first movable portion within the second movable portion enables extended vertical travel. As one nested portion extends relative to the other, the edge ring achieves greater movable range while the nested structure itself prevents gap formation, simultaneously improving plasma uniformity and maintaining reliability.
Solution Approach 2:
The patent transforms the static edge ring into a dynamic, multi-stage movable structure. The first and second movable portions can adjust their positions dynamically, allowing the edge ring to achieve various heights and maintain optimal plasma uniformity across different processing conditions without sacrificing reliability.
3Device complexity
If the edge ring structure is simplified, then device complexity is reduced, but the vertically movable range is limited
Solution Approach 1:
The nested structure provides an elegant solution that achieves extended movable range without proportionally increasing overall complexity. By nesting the first movable portion within the second, the patent creates a compact telescopic mechanism that delivers greater vertical travel while maintaining a relatively simple overall structure compared to alternative extended mechanisms.
Solution Approach 2:
Dividing the edge ring into segmented movable portions allows each segment to be relatively simple in structure while the combination of segments achieves the desired extended movable range. This segmentation approach balances structural simplicity with functional capability.
Data Source
AI summary
According to one embodiment, an edge ring is provided which includes a first movable portion provided along an outer circumference of a support portion having an upper surface capable of holding a semiconductor substrate thereon, the first movable portion being movable in a direction perpendicular to the upper surface; a second movable portion provided along an outer circumference of the first movable portion, the second movable portion being movable in the direction; and a driving portion capable of moving the first movable portion in the direction by way of the second movable portion.