Metrology for trace water in ultra-pure process gases

Short Name: PROMETH2O, Project Number: 20IND06
Image of a Scientist Working on Silicon Wafer Fabrication in Cleanroom
Scientist Working on Silicon Wafer Fabrication in Cleanroom

Higher performance optical-based methods to serve the humidity measurement supply chain

Water vapour is a hard to eliminate contaminant for the speciality gases industry. Within a European market set to be worth more than €20 BN a year by 2027, ultra-pure gases, such as argon, nitrogen, and hydrogen, are valued for protecting processes such as semiconductor manufacturing, where optimising failure rates offers prized competitive advantage.


Trace water contamination of just a few parts per billion (ppb) can result in circuit failures; the target is for measurements of water vapour in gases to span nine orders of magnitude. This presents a significant measurement challenge for gas producers and analytical instrument makers. Industry roadmaps see no let-up in demand for increased performance, specifying demand for methods delivering measurements in the fraction range between five parts per million and five ppb. While mid-to-high range measurements have been investigated and standards exist, current methods are inaccurate in some temperature and pressure ranges and for several carrier gases, while existing optical methods rely on some questioned extrapolations.


The project will develop a range of optical methods, including for gases other than nitrogen, down to 5 ppb, a primary method to measure amount fractions down to 50 ppb, and validate chilled-mirror hygrometers down to -105 C. An inter-comparison of trace water measurements will then be proposed to encourage the take-up of the developed technologies and measurement infrastructure in the measurement supply chain.


The resulting new sensors and primary standards will offer improved measurement accuracy for gas producers and analytical instrument makers, and confer competitive advantage for European high-technology industries.


Project website
Other Participants
Danmarks Tekniske Universitet (Denmark)
MBW Calibration AG (Switzerland)
Nippon Gases Industrial S.r.l. (Italy)
Qrometric Limited (United Kingdom)
Universidad De Valladolid (Spain)
Università degli studi della Campania Luigi Vanvitelli (Italy)
Università degli Studi di Cassino e del Lazio Meridionale (Italy)
Vaisala Oyj (Finland)