Anion formation in sputter ion sources by neutral resonant ionization

Journal Article · Mon Feb 15 00:00:00 EST 2016 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.4934618· OSTI ID:22482857

Vogel, J. S., E-mail: [e-mail] ^[1]

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1. University of California, 8300 Feliz Creek Dr., Ukiah, California 95482 (United States)

Focused Cs{sup +} beams in sputter ion sources create mm-diameter pits supporting small plasmas that control anionization efficiencies. Sputtering produces overwhelmingly neutral products that the plasma can ionize as in a charge-change vapor. Electron capture between neutral atoms rises as the inverse square of the difference between the ionization potential of the Cs state and the electron affinity of the sputtered atom, allowing resonant ionization at very low energies. A plasma collision-radiation model followed electronic excitation up to Cs(7d). High modeled Cs(7d) in a 0.5 mm recess explains the 80 μA/mm{sup 2} C{sup −} current density compared to the 20 μA/mm{sup 2} from a 1 mm recess.

• OSTI ID: 22482857
• Journal Information: Review of Scientific Instruments, Vol. 87, Issue 2; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
AFFINITY
ANIONS
ATOMS
BEAMS
CESIUM IONS
COLLISIONS
CONTROL
CURRENT DENSITY
ELECTRON CAPTURE
EXCITATION
ION SOURCES
IONIZATION
PLASMA
SPECTROSCOPY
SPUTTERING
VAPORS