The cycle that empties a saturated cryopump: the cold stages are warmed, usually with heaters and a dry nitrogen purge, the released gas is roughed away, and the pump is cooled back to operating temperature. A full regen takes several hours, while a fast or partial regen warms only part of the pump. Techs schedule regens by accumulated argon or hydrogen load, or when the second-stage temperature drifts above about 20 K.
Cryo on PVD 2 is in regen till about 3 a.m., don't queue any lots on that chamber.
Also heard as
- regeneration
- regen cycle
Related terms
Cryopump
Capture pump that freezes and adsorbs gas onto surfaces cooled to about 10 to 20 K by a closed-cycle refrigerator.
Crossover
Point in a pump-down where pumping switches from the roughing pump to the high vacuum pump.
Rough out
To pump a vented chamber from atmosphere to crossover with the roughing pump, before the high vacuum valve opens.