Polycold Cryochiller
Introduction
Installation and Operation Manual
Theory of Operation
Brooks Automation
214072 Revision B
1-5
Water Vapor Capturing in High Vacuum Systems
Water vapor can be up to 95% of the residual gas in high-vacuum chambers and is typically the most
reactive contaminant in such systems. The exceptionally high water vapor pumping speed provided by
the Cryochiller greatly increases product throughput and produces higher film quality, better adhesion,
and more reproducible deposition.
When capturing water vapor in high vacuum systems, the cryosurface is normally a coil. A rapid inter-
change between the cold and defrost states frees up valuable cycle time and increases product
throughput.
As the vacuum chamber begins the pump down sequence, the pre-programmed Polycold Cryochiller
can exit the Standby mode and quickly cool the cryocoil, providing much higher pumping speeds than
traditional vacuum pumps and significantly reducing chamber pump down time.
During the deposition process, the Polycold Cryochiller remains in the Cool mode to greatly reduce
water vapor contamination and increase product yield. During chamber venting, the Polycold Cryo-
chiller quickly heats the cryocoil to defrost and sublime the captured water vapor.
In this application, the cryocoil can be mounted directly in the vacuum chamber so conductance is not
limited by ports, manifolds, valves and baffles. The cryocoil is easy to install and can be adapted to fit
any system. It does not need a high vacuum valve. See