IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Vacuum Science & Technology Monday Sessions
       Session VST-MoA

Paper VST-MoA6
Sputter-ion Pump Element Cathode to Reduce Noble Gas Instabilities

Monday, October 29, 2001, 3:40 pm, Room 125

Session: Dry, Cryo & Other Forms of Pumping
Presenter: C.M. Schwie, Physical Electronics
Correspondent: Click to Email

Research not yet completed. Sputter-ion pumps have long been used to create reliable ultra-high vacuum environments. However, in certain applications, sputter-ion pumps have demonstrated instability when subjected to noble gas loading. The most stable method of pumping noble gases (e.g. argon) has historically been to employ combinations of titanium with tantalum in the pumping element. This paper evaluates new pumping element design approaches to enhance the Physical Electronics noble gas element. A solution to the problem of re-release (outgassing) of gases under vacuum lies mainly in the element's anode/cathode design. Various techniques were applied to aid the vacuum stability of a sputter-ion pump. These techniques involve employing cathode materials at various volumetric ratios and configurations to customize the pump to its expected operating environment. In addition to vacuum stability, pump speed, ultimate pressure, life, and manufacturability are the chief concerns. The evaluated designs also allow for customization of the pumping element (anode/cathode assembly) to the operating environment. The variation of cathode material ratios is an attempt to tailor the vacuum pump to the gas species present in the system. This will allow the vacuum user to achieve a proper balance between pumping speed and stability. This paper evaluates vacuum pump stability, speed (in accordance with ISO 3556), ultimate pressure, and life with the new cathode configurations. For more information contact: Name: Chester Schwie Job title: Mechanical Engineer Email address: cschwie@phi.com.