High vacuum pumps and ultrahigh vacuum pumps use a number of different technologies to perform their necessary functions. These include turbomolecular pumps, molecular drag, diffusion pumps, ion pumps, cryogenic pumps, and Getter or titanium sublimation pumps (TSP).

High vacuum and ultrahigh vacuum levels are used in many scientific and industrial systems such as vcuum furnaces, vacuum glove boxes, vacuum melting and casting,  pharmaceutical preparation, degassing, semiconductor manufacturing, and analytical equipment.

Diffusion pumps use jets of diffusion oil vapor to impart momentum and sweep gas molecules from the system. Diffusion pumps have no moving parts and provide the highest pumping speed for lighter gases like helium and hydrogen. Diffusion pump oil can “back stream”  very minute molecules off diffusion pump oil into the system causing process contamination.. Solutions to this for extremely sensitive process conditions include:  using special diffusion pump oils that are less volatile [but more expensive], installing a cold cap in the diffusion pump, installing a water baffle[ which cuts the pumping speed], install a refrigerated or liquid nitrogen cooled trap [which increases the pumping speed]
 

Turbomolecular high vacuum pumps use a series of high-speed rotors (25,000 to 75,000 rpm) and flow stabilizing, stationary stators to impart a preferential motion to gas molecules and create molecular flow through the pump.  They are also known as axial flow turbines.

Molecular drag pump are similar to turbomolecular pumps except a rotor drum with a ridged surface and cylindrical stator are used in place of stator and rotor blades to impart a preferential motion to gas molecules and create molecular flow through the pump.  Hybrid high vacuum pumps are available that use combinations of blades and ridged drums..

Ion pumps utilize a sputtering process to ionize then entrain gas molecules and trap them into the anode or cathode wall.  The entrapment process can utilize a getter such as titanium to bind the molecules.  They can operate in the ultra high vacuum (UHV) range and eliminate contamination by organic molecules.

Cryogenic pumps use extremely cold (liquid N₂ and He temperatures) surfaces and absorption surfaces freeze or trap molecules. Cryogenic pumps can operate with relatively high fore line or exhaust pressures. Cryogenic high vacuum pumps must be periodically re-generated to purge the frozen or trapped gases. 

Cryosorption pumps evacuate gas molecules from a volume by adsorbing them on the chilled surface of a molecular sieve. These molecular sieves are designed to have a large surface area-to-volume ratio to maximize the adsorbing area.

Getter or titanium sublimation pumps (TSP) entrain gas molecules in a getter, or material that is vaporized in order to absorb or capture the molecules, and trap them on the cold outer wall of the chamber.  These high vacuum pumps may also use "non-evaporating gettering adsorption and absorption techniques by using a large-surface-area porous matrix for entrainment

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