AVS 60th International Symposium and Exhibition
    Vacuum Technology Monday Sessions
       Session VT-MoM

Paper VT-MoM9
An Inverted Magnetron Pirani Combination Gauge with Low Magnetic Stray Fields

Monday, October 28, 2013, 11:00 am, Room 202 C

Session: Vacuum Measurement and Metrology
Presenter: M. Wüest, INFICON Ltd, Liechtenstein
Authors: M. Wüest, INFICON Ltd, Liechtenstein
B. Andreaus, INFICON Ltd, Liechtenstein
J. Marki, INFICON Ltd, Liechtenstein
R. Enderes, INFICON Ltd, Liechtenstein
D. Oertel, INFICON Ltd, Liechtenstein
Correspondent: Click to Email
Electromagnetic interference from low-intensity static magnetic fields has been observed to affect the operation of pacemakers and other medical electronic devices. The ICNIRP Guidelines [1] recommend that those devices are not adversely affected by static magnetic fields below 0.5 mT. This recommendation has been incorporated into the Semiconductor Manufacturing Standard SEMI S2-0302 [2] and requires that the magnetic field at exterior surfaces of the equipment (2 to 3 cm from the surface) has to be smaller than 0.5 mT or a pacemaker warning needs to be posted. For these reasons, presently available cold cathode gauges should (but most do not) carry a pacemaker warning label, because they do not fulfill the SEMI S2 standard. We have developed an inverted magnetron that has a novel magnetic field design with exterior magnetic stray fields below the threshold set by the SEMI norm. Therefore, this device does not need to carry a warning label. A low external magnetic field is also of benefit to analytical instrumentation, where the external magnetic field might influence the trajectories of ions. We will present the magnetic design and other pertinent features of this inverted magnetron gauge. [1] Guidelines on Limits of Exposure to Static Magnetic Fields, International Commission on Non-Ionizing Radiation Protection, 2009. [2] Environmental, Health, and Safety Guideline for Semiconductor Manufacturing Equipment, Semi S2-0302, Appendix 5, 2002.