Stacked Plasma-Resistant Coating for Crack-Free Yttrium Layers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing plasma-based manufacturing processes for electronic devices face issues with contaminant particle generation and surface cracks due to the use of highly chemically active radicals and dissociated ions, which damage components and affect process uniformity.
Innovation Solution
A plasma-resistant member with a stacked structure comprising a lower layer of yttrium oxide, a buffer layer of yttria-stabilized zirconia, and an upper layer of yttrium oxyfluoride or fluorine-rich yttrium oxide, deposited through vapor deposition, to manage thermal expansion coefficients and reduce surface roughness and crack generation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional spray coating method is used to form a plasma-resistant coating layer, then the coating can be applied to protect components, but the coating contains a loose structure with many voids that generates contaminant particles
Solution Approach 1:
The patent applies a stacked composite structure consisting of a lower layer (yttrium oxide), a buffer layer (yttria-stabilized zirconia), and an upper layer (yttrium oxyfluoride or fluorine-rich yttrium oxide). This composite structure combines materials with different properties to achieve both plasma resistance and a dense, contaminant-free surface, resolving the contradiction between protection and contamination.
Solution Approach 2:
The patent changes the physical and chemical parameters of the coating by selecting materials with specific thermal expansion coefficients and chemical compositions. The buffer layer's thermal expansion coefficient is specifically chosen to be between that of the lower and upper layers, reducing stress and improving density to eliminate contaminant generation while maintaining plasma resistance.
2Reliability
If a conventional spray coating method is used to form a plasma-resistant coating layer, then the coating can be applied to protect components, but the coating has surface cracks due to thermal expansion coefficient differences
Solution Approach 1:
The buffer layer acts as an intermediary between the lower layer and the upper layer. Its thermal expansion coefficient is specifically designed to be between those of the adjacent layers, serving as a transition that reduces thermal stress and prevents crack formation, thereby maintaining surface integrity while preserving plasma resistance.
Solution Approach 2:
The stacked composite structure with carefully selected material properties creates a gradient in thermal expansion coefficients, which accommodates thermal stress and prevents crack formation while maintaining the protective function against plasma.
3Reliability
If a plasma-resistant coating layer is formed through spray coating, then the coating can be applied, but a heat treatment process for sintering is required which complicates the manufacturing process
Solution Approach 1:
The patent replaces the conventional spray coating method with a vapor deposition method. This substitution eliminates the need for subsequent sintering heat treatment, as vapor deposition directly forms a dense, adherent coating that does not require thermal processing, thereby simplifying the manufacturing process while maintaining plasma resistance.
4Device complexity
If the upper layer directly contacts the lower layer, then the structure is simpler, but the surface roughness increases and crack generation occurs due to thermal expansion coefficient differences
Solution Approach 1:
The buffer layer serves as a mediator between the upper and lower layers, reducing the impact of thermal expansion coefficient differences. This intermediary layer minimizes interfacial stress, reduces surface roughness, and prevents crack formation, justifying the increased structural complexity by significantly improving manufacturing precision and coating quality.
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 stacked structure effectively suppresses contaminant particle formation and improves plasma composition uniformity, enhancing the lifespan and quality of plasma-resistant coatings without requiring a sintering process.
Implementation Method 1
the stacked structure having plasma resistance can be formed through vapor deposition
Data Source
AI summary
A plasma-resistant member includes a lower layer disposed on a substrate and including yttrium oxide, a buffer layer disposed on the lower layer, and an upper layer disposed on the buffer layer and including yttrium oxyfluoride or fluorine-rich yttrium oxide, wherein the buffer layer has a thermal expansion coefficient between a thermal expansion coefficient of the upper layer and a thermal expansion coefficient of the lower layer.