skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Effective removal of field-emitting sites from metallic surfaces by dry ice cleaning

Journal Article · · Journal of Applied Physics
DOI:https://doi.org/10.1063/1.2772505· OSTI ID:21057515
; ; ; ;  [1]
  1. FB C Physik, Bergische Universitaet Wuppertal, D-42097 Wuppertal (Germany)

Systematic results of the field emission properties of polycrystalline copper and niobium and single-crystal Nb are reported. Dry ice cleaning (DIC) is found to suppress enhanced field emission from metallic surfaces. The cleaning effect on the emitting sites was investigated by means of field emission scanning microscopy up to fields of 250 MV/m and high-resolution scanning electron microscopy with energy dispersive x-ray analysis. The number density of emitters at given fields was drastically reduced by dry ice cleaning. Current-voltage measurements and derived Fowler-Nordheim parameters are partially discussed with respect to the morphology and impurity content of localized emitters. No emission from grain boundaries on large-grain Nb samples was observed. The microscopy results prove the effective removal of field-emitting particulates down to 400 nm as well as the partial smoothing of surface protrusions by DIC.

OSTI ID:
21057515
Journal Information:
Journal of Applied Physics, Vol. 102, Issue 4; Other Information: DOI: 10.1063/1.2772505; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
Country of Publication:
United States
Language:
English