Yttrium-Containing Cover Ring for Plasma Chamber
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Plasma etching in semiconductor processing often results in non-uniform gas distribution and contamination from by-products, leading to poor processing results and increased maintenance needs, particularly as critical dimensions shrink and devices are packed more densely on substrates.
Innovation Solution
A cover ring for plasma processing chambers fabricated from yttrium-containing materials, featuring specific geometries and orientations that enhance corrosion resistance and facilitate improved plasma uniformity and in-situ cleaning, reducing the need for frequent replacement and improving etching performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional chamber components are used, then initial processing can proceed, but contamination from by-products accumulates rapidly requiring frequent cleaning
Solution Approach 1:
The patent applies parameter changes by modifying the material composition of the cover ring to contain yttrium oxide (Y2O3) at concentrations of 1-10%, which fundamentally alters the surface properties and chemical resistance of the component. This material parameter change enables the component to resist contamination from etching by-products, extending service life from typical cleaning intervals to over 1000 RF hours between cleanings.
Solution Approach 2:
The patent employs composite materials by combining yttrium oxide with traditional chamber component materials. The yttrium-containing material creates a composite structure that maintains the mechanical properties of the base material while adding chemical inertness and resistance to plasma by-products, thereby reducing contamination accumulation and extending component reliability.
2Productivity
If critical dimensions are reduced to increase device density, then productivity increases, but plasma uniformity deteriorates leading to poor processing results
Solution Approach 1:
The patent applies local quality by designing the cover ring with specific geometric features including a sloped top surface and localized yttrium-containing material distribution. These local modifications create controlled plasma interaction zones that improve plasma uniformity specifically at the substrate edges, enabling precise processing even as device density increases and critical dimensions shrink.
Solution Approach 2:
The patent introduces dimensional changes through the sloped top surface geometry of the cover ring. This angular feature (with slopes of 15-45 degrees) adds a geometric dimension to plasma distribution control, redirecting plasma flow to improve uniformity across the substrate surface and enabling continued productivity gains as device pitch decreases.
3Manufacturing precision
If cleaning frequency is increased to maintain processing quality, then manufacturing precision is maintained, but productivity decreases due to downtime
Solution Approach 1:
The patent changes the material parameter of the cover ring to include yttrium oxide, which fundamentally alters the surface chemistry and reduces by-product adhesion. This parameter change extends the time between cleaning cycles from typical intervals to over 1000 RF hours, maintaining processing quality while minimizing downtime and maximizing productivity.
Solution Approach 2:
The patent effectively creates a long-lasting component by using yttrium-containing materials that resist contamination. Instead of requiring frequent replacement or cleaning of conventional components, the yttrium-modified cover ring serves as a durable, low-maintenance component that maintains processing precision over extended periods, reducing the need for frequent maintenance interventions.
Data Source
AI summary
Embodiments of a cover ring for use in a plasma processing chamber are provided. In one embodiment, a cover ring for use in a plasma processing chamber includes a ring-shaped body fabricated from a yttrium (Y) containing material. The body includes a bottom surface having an inner locating ring and an outer locating ring. The inner locating ring extends further from the body than the outer locating ring. The body includes an inner diameter wall having a main wall and a secondary wall separated by a substantially horizontal land. The body also includes a top surface having an outer sloped top surface meeting an inner sloped surface at an apex. The inner sloped surface defines an angle with a line perpendicular to a centerline of the body less than about 70 degrees.