Behavior of titanium sublimation and sputter-ion pumps in the 10/sup -11/ Torr range

Journal Article · Sat Jan 01 04:00:00 EST 1977 · J. Vac. Sci. Technol.; (United States)

DOI:https://doi.org/10.1116/1.569295· OSTI ID:7317421

Halama, H J

In the proposed Intersecting Storage Accelerator, ISABELLE, 1200 pumping stations will be used to keep two 3-km-long rings at a pressure of 1 x 10/sup -11/ Torr (1.3 x 10/sup -9/ Pa). It is clear that in such a large system, price and simplicity are very important. We have therefore undertaken a study on a well-instrumented room-temperature vacuum system with a surface area of 6000 cm/sup 2/ and a volume of 17 l, pumped by a Ti-ball sublimator and an ion pump. Total pressure and residual gas composition were measured by a Helmer gauge and a quadrupole mass spectrometer. The final pressures of approx.1 x 10/sup -11/ Torr (approx.1.3 x 10/sup -9/Pa) were reached with Ti films and a 20-l s/sup -1/ sputter-ion pump. The main residual gas components were hydrogen and methane. The ultimate pressure was determined primarily by the ability of Ti films to pump H/sub 2/ and depends on the method of laying down the film and the surface temperature. Previous surface preparation seemed relatively unimportant. Two methods of pumping CH/sub 4/ were investigated, namely, (a) cracking the molecules on hot tungsten filament and (b) conventional sputter-ion pumping. Sputter-ion pumping was found to be more efficient and preferable.

• Research Organization: Brookhaven National Laboratory, Upton, New York 11973
• OSTI ID: 7317421
• Journal Information: J. Vac. Sci. Technol.; (United States), Journal Name: J. Vac. Sci. Technol.; (United States) Vol. 14:1; ISSN JVSTA
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420700* -- Engineering-- Vacuum Engineering-- (-1987)
ACCELERATORS
ALKANES
CHEMICAL REACTIONS
CRACKING
CRYOGENIC FLUIDS
DECOMPOSITION
DEGASSING
EFFICIENCY
ELEMENTS
EVAPORATION
FILMS
FLUIDS
GAS ANALYSIS
HYDROCARBONS
ISABELLE STORAGE RINGS
LABORATORY EQUIPMENT
METALS
METHANE
ORGANIC COMPOUNDS
PHASE TRANSFORMATIONS
PUMPING
PUMPS
PYROLYSIS
SPUTTER-ION PUMPS
STORAGE RINGS
SUBLIMATION
TITANIUM
TRANSITION ELEMENTS
ULTRAHIGH VACUUM
VACUUM PUMPS
VACUUM SYSTEMS