US 7,320,224 B2
Method and apparatus for detecting and measuring state of fullness in cryopumps
Gary S. Ash, Dartmouth, Mass. (US); Allen J. Bartlett, Milford, Mass. (US); James A. O'Neil, Bedford, Mass. (US); and Bruce R. Andeen, Boxborough, Mass. (US)
Assigned to Brooks Automation, Inc., Chelmsford, Mass. (US)
Filed on Jan. 21, 2004, as Appl. No. 10/763,056.
Prior Publication US 2005/0155358 A1, Jul. 21, 2005
Int. Cl. B01D 8/00 (2006.01)
U.S. Cl. 62—55.5 66 Claims
OG exemplary drawing
 
1. A method of measuring fullness of a cryopump that evacuates a processing volume comprising:
coupling a total pressure gauge in direct fluid communication with an inner vacuum region behind a condensing surface distinct from an outer vacuum region outside the condensing surface, the inner vacuum region including an adsorbent for adsorbing non-condensable gases in a cryopump;
during processing or recovery from processing cycles, measuring pressure of the inner vacuum region with the pressure gauge, the measured pressure being substantially less than the pressure in the outer vacuum region outside of the condensing surface; and
determining an adsorption capacity of the adsorbent using the measured pressure.