Title:
IONIZATION VACUUM GAUGE
Document Type and Number:
Japanese Patent JP3739141
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To enlarge the lower limit of extremely high vacuum measuring range by providing a charged particle shielding electrode in a space communicating between a vacuum gauge container and a vacuum chamber to be measured thereby blocking intrusion of a charged particle from other charged particle source.
SOLUTION: Gas molecules flying from the inner space 100 of a vacuum chamber 10 to be measured pass through a passage, i.e., a space 200, and enter into a vacuum gauge container 11. A planar charge particle shielding electrode 31 is arranged in the vicinity of the opening 200a of the space 200 while partially covering the opening 200a. A required negative pressure is applied to the shielding electrode 31 from a DC power supply 32 and the shielding electrode 31 is held at a negative potential. Consequently, an electron 27 flying from other electron source 26 located at other part of the vacuum chamber 10 toward a filament can be intercepted. More specifically, linearity of measurement can be improved by the charged particle shielding effect based on the shielding electrode 31 and the lower limit of extremely high vacuum measuring range can be extended.
Inventors:
Kawasaki Yosuke
Application Number:
JP21320396A
Publication Date:
January 25, 2006
Filing Date:
July 24, 1996
Export Citation:
Assignee:
Canon ANELVA Corporation
International Classes:
G01L21/30; (IPC1-7): G01L21/30
Domestic Patent References:
| JP60188350U | ||||
| JP62024122A | ||||
| JP7027648A |
Attorney, Agent or Firm:
Tamiya Hiroshi
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