Aluminum Oxide Dewpoint Transmitter Application Note - Glove Boxes
Application: Glove Boxes
Glove boxes or isolation chambers provide a controlled and pure environment for a wide variety of applications. Inert gases are used in a glove box to blanket the containment in a neutral background environment. Examples of glove box applications include carrying out reactions with delicate or hazardous materials, sensitive micro-assembly of electronic devices, high purity welding, lithium battery manufacture, pharmaceutical manufacture, and semiconductor lithography. Typical blanketing gases are nitrogen, helium, and argon.
To ensure the blanketing gas has properly purged the environment, moisture sensors are installed within glove box environment, on the purge gas exhaust or in the supply side stream.
Why Dewpoint Measurement is desired/required:
The presence of moisture in the blanketing gas for a glove box or isolation chamber can cause serious contamination problems. For example, moisture or oxygen may change yields, enable side reactions with reactants or products, or affect the end product’s surface finish or structural integrity.
Typical Application Conditions/Parameters:
- From less than 1 PPMv to 10,000 PPMv
- Dew points from -80oC to +10oC (-112 oF to +50 oF)
- Slight vacuum to slight positive pressure
- Typically room ambient
Potential Sample Systems depending on the conditions of the instrument air line:
A. Positive Pressure Process Line Installation: Typical Sample System:
B. Vacuum Pressure Process Line Installation: Typical Sample System: