Nonevaporable getter coating chambers for extreme high vacuum

Stutzman, Marcy L.; Adderley, Philip A.; Mamun, Md Abdullah Al; Poelker, Matt

doi:10.1116/1.5010154

Title: Nonevaporable getter coating chambers for extreme high vacuum

Abstract

Techniques for NEG coating a large diameter chamber are presented along with vacuum measurements in the chamber using several pumping configurations, with base pressure as low as 1.56x10^-12 Torr (N2 equivalent) with only a NEG coating and small ion pump. We then describe modifications to the NEG coating process to coat complex geometry chambers for ultra-cold atom trap experiments. Surface analysis of NEG coated samples are used to measure composition and morphology of the thin films. Finally, pressure measurements are compared for two NEG coated polarized electron source chambers: the 130 kV polarized electron source at Jefferson Lab and the upgraded 350 kV polarized 2 electron source, both of which are approaching or within the extreme high vacuum (XHV) range, defined as P<7.5x10^-13 Torr.

Authors:

Stutzman, Marcy L. ^[1]; Adderley, Philip A. ^[1]; Mamun, Md Abdullah Al ^[1];

^[1]

Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

Publication Date:: 2018-03-01

Research Org.:: Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Nuclear Physics (NP)

OSTI Identifier:: 1439842

Alternate Identifier(s):: OSTI ID: 1429947

Report Number(s):: JLAB-ACC-18-2671; DOE/OR/23177-4377; arXiv:1803.07056
Journal ID: ISSN 0734-2101; TRN: US1900637

Grant/Contract Number:: AC05-06OR23177

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films

Additional Journal Information:: Journal Volume: 36; Journal Issue: 3; Journal ID: ISSN 0734-2101

Publisher:: American Vacuum Society

Country of Publication:: United States

Language:: English

Subject:: 47 OTHER INSTRUMENTATION

Citation Formats


                    Stutzman, Marcy L., Adderley, Philip A., Mamun, Md Abdullah Al, and Poelker, Matt. Nonevaporable getter coating chambers for extreme high vacuum.  United States: N. p., 2018. 
Web.  doi:10.1116/1.5010154.

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                    Stutzman, Marcy L., Adderley, Philip A., Mamun, Md Abdullah Al, & Poelker, Matt. Nonevaporable getter coating chambers for extreme high vacuum.  United States.  https://doi.org/10.1116/1.5010154

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                    Stutzman, Marcy L., Adderley, Philip A., Mamun, Md Abdullah Al, and Poelker, Matt. Thu .  
"Nonevaporable getter coating chambers for extreme high vacuum".  United States.  https://doi.org/10.1116/1.5010154.  https://www.osti.gov/servlets/purl/1439842.

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@article{osti_1439842,

  title        = {Nonevaporable getter coating chambers for extreme high vacuum},

  author       = {Stutzman, Marcy L. and Adderley, Philip A. and Mamun, Md Abdullah Al and Poelker, Matt},

  abstractNote = {Techniques for NEG coating a large diameter chamber are presented along with vacuum measurements in the chamber using several pumping configurations, with base pressure as low as 1.56x10^-12 Torr (N2 equivalent) with only a NEG coating and small ion pump. We then describe modifications to the NEG coating process to coat complex geometry chambers for ultra-cold atom trap experiments. Surface analysis of NEG coated samples are used to measure composition and morphology of the thin films. Finally, pressure measurements are compared for two NEG coated polarized electron source chambers: the 130 kV polarized electron source at Jefferson Lab and the upgraded 350 kV polarized 2 electron source, both of which are approaching or within the extreme high vacuum (XHV) range, defined as P<7.5x10^-13 Torr.},

  doi          = {10.1116/1.5010154},

  journal      = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},

  number       = 3,

  volume       = 36,

  place        = {United States},

  year         = {2018},

  month        = {3}

}

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Figures / Tables:

Figure 1: NEG chamber coating schematic showing the chamber, leak valve for the gas inlet, viewport, insulating/biasing NEG wire support with spring tensioners, and pumping system with pressure measurement.

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