Smoothing RF cavities with gas cluster ions to mitigate high voltage breakdown

D. R. Swenson, E. Degenkolb, Z. Insepov, L. Laurent, G. Scheitrum

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

Many studies have demonstrated that improving the surface smoothness and cleanliness of high voltage electrodes increases the voltage standoff capability, but none have specifically investigated the role of nano-scale and atomic level surface roughness. Using AFM imaging, we have studied the effect of gas cluster ion beams (GCIB) on oxygen-free Cu electrode material that is used in high gradient RF cavities. Using Ar clusters accelerated by 30 kV, with a dose of 6 × 1014 e cm-2, we have effectively removed an asperity that was 3500 Å wide and 350 Å high. Subsequent processing with 5 kV acceleration reduced the surface roughness from an Ra value of 13.2 Å to 4.8 Å. This demonstrates the effectiveness of GCIB for reducing sub-micron roughness to atom level smoothness.

Original languageEnglish
Pages (from-to)641-644
Number of pages4
JournalNuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms
Volume241
Issue number1-4
DOIs
Publication statusPublished - Dec 2005
Externally publishedYes

Fingerprint

Electric breakdown
electrical faults
smoothing
high voltages
Gases
Surface roughness
Ions
Ion beams
cavities
surface roughness
ion beams
gases
cleanliness
ions
Electrodes
Electric potential
electrode materials
roughness
atomic force microscopy
Oxygen

Keywords

  • Cluster beam
  • Cluster-surface interactions
  • Kilpatrick limit
  • RF breakdown

ASJC Scopus subject areas

  • Surfaces, Coatings and Films
  • Instrumentation
  • Surfaces and Interfaces

Cite this

Smoothing RF cavities with gas cluster ions to mitigate high voltage breakdown. / Swenson, D. R.; Degenkolb, E.; Insepov, Z.; Laurent, L.; Scheitrum, G.

In: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms, Vol. 241, No. 1-4, 12.2005, p. 641-644.

Research output: Contribution to journalArticle

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