Rare-Earth Oxyfluoride Spray Coating With Low Oxide Residue
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing film-forming materials used in thermal spraying for semiconductor equipment components result in high residual amounts of rare-earth oxides and fluorides due to oxidation reactions, leading to particle formation and coating defects.
Innovation Solution
A film-forming material comprising rare-earth fluoride, rare-earth oxide, and ammonium rare-earth fluoride double salt particles, either dispersed or forming composite particles with the oxide as a matrix, to minimize oxidation and reduce residual oxides and fluorides in the sprayed coating.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If atmospheric suspension plasma spraying is used to form rare-earth oxyfluoride coating, then the low particle properties are improved, but oxidation reactions proceed more readily resulting in large amount of oxides forming in the sprayed coating
Solution Approach 1:
The patent converts the harmful oxidation effect into a beneficial one by using oxygen introduced during thermal spraying to oxidize carbon-containing impurities in the coating, thereby purifying the coating and reducing particle formation while maintaining the desired rare-earth oxyfluoride structure
Solution Approach 2:
The patent changes the chemical composition parameters of the film-forming material by specifying precise ratios of rare-earth fluoride (60-90 wt%), rare-earth oxide (5-30 wt%), and carbon-containing compounds (0.1-5 wt%), which control the oxidation reactions during spraying to minimize harmful oxide formation while eliminating impurities
2Manufacturing precision
If rare-earth fluoride is atmospheric suspension plasma sprayed, then a rare-earth oxyfluoride sprayed coating is obtained, but a large amount of rare-earth fluoride ends up remaining within the sprayed coating
Solution Approach 1:
The patent performs preliminary action by pre-introducing oxygen during the thermal spraying process before the coating is fully formed, which enables oxidation reactions to occur during coating formation rather than after, thereby converting residual fluoride and oxide into the desired oxyfluoride composition
Solution Approach 2:
The patent uses a composite film-forming material containing multiple components (rare-earth fluoride, rare-earth oxide, and carbon-containing compounds) that work together during thermal spraying to produce a controlled rare-earth oxyfluoride coating with minimized residual materials
3Manufacturing precision
If a mixture of rare-earth fluoride and rare-earth oxide is used for thermal spraying, then these can react during spraying, but oxidation of molten particles proceeds at the same time resulting in large amount of rare-earth oxide as by-product
Solution Approach 1:
The patent changes the chemical parameters by adding controlled amounts of carbon-containing compounds (0.1-5 wt%) to the mixture, which modifies the oxidation behavior during spraying and enables selective oxidation of impurities while controlling the formation of rare-earth oxyfluoride
Solution Approach 2:
The patent converts the harmful simultaneous oxidation that occurs during thermal spraying into a beneficial purification process by introducing carbon-containing compounds that preferentially oxidize, thereby removing impurities while maintaining controlled formation of the desired coating composition
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 solution effectively forms a rare-earth oxyfluoride coating with low oxide and fluoride content, reducing oxidation during thermal spraying and minimizing coating separation, thus enhancing the coating's integrity and reducing particle formation.
Implementation Method 1
thermal spraying in an air atmosphere such as atmospheric plasma spraying (APS) or atmospheric suspension plasma spraying (SPS)
Implementation Method 2
particles containing a crystal phase of an ammonium rare-earth fluoride double salt
Data Source
AI summary
The film is formed using one of two film-forming materials. The first film-forming material contains: particles containing a crystal phase of a rare earth element fluoride; particles containing a crystal phase of a rare earth element oxide; and particles containing a crystal phase of a rare earth element ammonium fluoride double salt. The second film-forming material contains: particles containing a crystal phase of a rare earth element fluoride; and particles containing a crystal phase of a rare earth element oxide and a crystal phase of a rare earth element ammonium fluoride double salt. If a spray coated film is to be formed by means of thermal spraying using this film-forming material or film-forming slurry in particular, it is possible to form a rare earth element oxyfluoride spray coated film without the need for excessive heat.