Solid Optical Medium for Airborne Molecular Contaminant Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for detecting and eliminating airborne molecular contaminants (AMCs) in semiconductor clean rooms are inefficient and costly, as they fail to accurately identify contaminants causing ultraviolet haze and require sophisticated, expensive analytical techniques or insensitive mass detection methods.
Innovation Solution
The use of a light beam from a solid optical medium to form deposits on its surface, which are detected by interferometry or observation of spherical aberration, and the application of radiolytic particle formation to selectively capture and analyze harmful AMCs, allowing for their removal and concentration for enhanced analytical sensitivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If sophisticated analytical methods such as gas chromatography and TOF-SIMS are used to identify gaseous chemical species, then measurement precision is improved, but device complexity and cost increase
Solution Approach 1:
The patent extracts only the harmful AMCs that form particles from the complex gas mixture by inducing radiolytic particle formation. Instead of analyzing all gaseous species with complex analytical methods, the system selectively converts problematic AMCs into detectable particles, simplifying the detection approach while maintaining precision for harmful contaminants.
Solution Approach 2:
The patent changes the physical state of AMCs by inducing radiolytic particle formation through controlled radiation exposure. This parameter change transforms undetectable gaseous contaminants into detectable particulate form, enabling simplified particle-based detection methods to achieve the same measurement precision as complex analytical techniques.
2Adaptability or versatility
If mechanical oscillators such as piezoelectric and surface acoustic wave devices are used to sense deposits by mass, then the method targets unknown contaminants capable of forming haze, but measurement precision deteriorates due to insufficient sensitivity
Solution Approach 1:
The patent changes the detection parameter from mass measurement to particle formation measurement. By inducing radiolytic particle formation and detecting the resulting particles, the system achieves much higher sensitivity than mass-based methods, while maintaining the ability to detect unknown contaminants that form haze.
Solution Approach 2:
The patent converts the harmful effect of AMCs (which form haze deposits) into a beneficial detection mechanism. By inducing radiolytic particle formation from the same AMCs that cause haze, the system transforms the problematic contaminants into detectable signals, achieving high sensitivity detection of harmful species.
3Reliability
If gas filters and absorbers are used to remove AMCs, then contaminant removal is achieved, but productivity deteriorates due to inability to reach parts-per-trillion purity levels and extended run-in times
Solution Approach 1:
The patent changes the removal mechanism from physical filtration to radiolytic particle formation followed by particle capture. This parameter change enables much more effective removal of AMCs at parts-per-trillion levels, achieving the required purity levels without extended run-in times and thus improving productivity.
4Reliability
If distillation is used to remove AMCs from air, then contaminant removal is achieved, but cost increases significantly
Solution Approach 1:
The patent extracts and removes only the harmful AMCs that form particles through radiolytic particle formation, rather than using energy-intensive distillation to remove all contaminants. This selective extraction approach achieves effective contaminant elimination at much lower energy cost.
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
This approach provides a cost-effective and sensitive method for detecting and removing only the contaminants that form ultraviolet haze, reducing interference from inactive species and improving analytical sensitivity by concentrating harmful AMCs.
Implementation Method 1
a light beam emerging from a solid optical medium causes the formation of deposits formed from the AMCs on the surface of the solid
Implementation Method 2
the first beam of electromagnetic radiation causing the airborne molecular contaminants to form deposits on the first surface of the solid medium
Implementation Method 3
Subtle changes in the wavefronts can be detected, for example by interferometry
Implementation Method 4
irradiating the gas stream with an ionizing radiation from the ionizing radiation source as the gas stream passes through the treatment chamber, the irradiating causing radiolytic formation of particles in the gas stream
Implementation Method 5
the irradiating causing radiolytic formation of particles in the gas stream
Data Source
AI summary
Methods and apparatuses for the removal, analysis and/or detection of harmful airborne molecular contaminants (AMCs). In one embodiment, an ionizing radiation source is utilized to remove the harmful AMCs from a flow stream via radiolytic particle generation and subsequent capture by filtration. The captured particles may be released, for example, by re-gasification for analysis at much higher concentrations. In another embodiment, the ionizing radiation source is utilized with a particle detector to sense when harmful AMCs are present. In one embodiment, a solid optical medium is exposed to a monitored environment so that the AMCs are in contact with a surface of the solid optical medium. A focused light beam is arranged to emerge from a solid optical medium at an energy density sufficient to cause the AMCs to form deposits on the exposed surface of the solid optical medium, which can be detected using an interferometric technique.