cryopump

The sample chamber also employs a cryopump to trap contaminants, especially water.

In this function, they are called a cryotrap or cold trap, even though the physical mechanism is the same as for a cryopump.

Regeneration of a cryopump is the process of evaporating the trapped gases.

They are only effective on some gases, depending on the freezing and boiling points of the gas relative to the cryopump's temperature.

A cryopump or turbomolecular pump would be used to bring the pressure further down to 10 Torr (1 Pa).

A cryopump or a "cryogenic pump" is a vacuum pump that traps gases and vapours by condensing them on a cold surface.

Baffles are often attached to the cold head to expand the surface area available for condensation, but they also increase the radiative heat uptake of the cryopump.

"Subsequently, the Gifford-McMahon cryogenic refrigeration cycle became the industry standard refrigeration cycle for cryopump applications in the rapidly growing semiconductor industry."

An additional ion pump can be started below 10 Torr to remove gases which are not adequately handled by a cryopump or turbo pump, such as helium or hydrogen.

Cold traps are also used in cryopump systems to generate hard vacua by condensing the major constituents of the atmosphere (nitrogen, oxygen, carbon dioxide and water) into their liquid or solid forms.

Best practice is to heat the whole chamber under vacuum to the highest temperature allowed by the materials, allow time for outgassing products to be exhausted by the mechanical pumps, and then cool and use the cryopump without breaking the vacuum.

Sorption pumps are a type of cryopump that is often used as roughing pumps to reduce pressures from the range of atmospheric to on the order of 0.1 Pa (10 Torr), while lower pressures are achieved using a finishing pump (see vacuum).