SiC Focus Ring Recrystallization via Plasma Heating
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing surface processing methods for structural members in plasma processing apparatuses, such as focus rings made of silicon carbide (SiC), are inefficient in removing fragmental layers, especially at stepped portions, leading to particle generation and reduced wafer production yield due to microcracks and stability issues with liquid chemicals and mechanical polishing.
Innovation Solution
A surface processing method that recrystallizes SiC by heating the focus ring using electron beam irradiation or plasma torches to convert the fragmental layer into a dense layer, preventing particle generation and improving surface uniformity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If mechanical polishing is used to remove fragmental layers, then surface uniformity is improved, but it is not suitable for stepped portions and requires high cost and long time
Solution Approach 1:
The patent replaces mechanical polishing with plasma processing to remove fragmental layers. The plasma processing method uses chemical reactions rather than mechanical abrasion, allowing it to effectively treat stepped portions and complex geometries that mechanical polishing cannot reach, while significantly reducing processing time and cost.
Solution Approach 2:
The patent changes the processing parameters by using plasma chemistry (reactive species, ion energy, gas composition) instead of mechanical contact. By controlling plasma parameters such as power, pressure, and gas flow, the method achieves effective fragmental layer removal across all surface geometries including stepped portions, improving both productivity and accessibility.
2Object-generated harmful factors
If liquid chemicals are used for surface processing, then particle removal is attempted, but SiC is stable to various liquid chemicals making the process ineffective
Solution Approach 1:
The patent substitutes liquid chemical processing with plasma processing. Plasma provides reactive species (ions, radicals, excited molecules) that can effectively react with and remove SiC fragmental layers, overcoming the chemical stability of SiC that renders liquid chemicals ineffective.
Solution Approach 2:
The patent changes the chemical environment from liquid phase to plasma phase. The plasma state provides higher energy reactive species and different reaction mechanisms that can break down SiC bonds and remove fragmental layers, effectively addressing the chemical stability issue of SiC materials.
3Object-generated harmful factors
If manual polishing operation is used to remove fragmental layers, then particle generation is reduced, but it requires high cost and long polishing time
Solution Approach 1:
The patent replaces manual polishing operations with automated plasma processing. The plasma processing system automatically removes fragmental layers through chemical reactions, eliminating the need for skilled manual operations and reducing both cost and time while maintaining effectiveness in particle generation reduction.
Solution Approach 2:
The plasma processing method is self-regulating and automatically adapts to different surface geometries including stepped portions. The plasma reacts with the fragmental layer material itself, requiring no complex manual intervention or specialized equipment operation, thereby reducing device complexity and operational requirements.
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 method effectively eliminates fragmental layers at stepped portions, reducing particle generation and enhancing surface roughness to levels comparable to mechanical polishing, thereby increasing wafer production yield and preventing contamination in plasma processing.
Implementation Method 1
heating the focus ring using electron beam irradiation
Implementation Method 2
heating the focus ring using electron beam irradiation or plasma torches
Implementation Method 3
heating the focus ring using electron beam irradiation or plasma torches
Implementation Method 4
heating the focus ring using electron beam irradiation or plasma torches
Implementation Method 5
recrystallizes SiC by heating the focus ring
Data Source
AI summary
In a surface processing method for processing a surface of a member made of silicon carbide (SiC) and having a fragmental layer on a surface thereof, the surface of the member having the fragmental layer is modified into a dense layer to reduce the number of particles generated from the surface of the member when the member is applied to a plasma processing apparatus. Here, the SiC of the surface of the member is recrystallized by heating the fragmental layer.