Production of intensive negative lithium beam with caesium sputter-type ion source

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

卷:415

Article

Lobanov, Nikolai R.¹ 

[1] Australian Natl Univ, Dept Nucl Phys, Res Sch Phys & Engn, Canberra, ACT, Australia

关键词: Negative ions;    Sputter sources;    Negative lithium beams;   

DOI  :  10.1016/j.nimb.2017.11.004

来源: Elsevier

【 摘 要 】

Compounds of lithium oxide, hydroxide and carbonate, mixed with silver, were prepared for use as a cathode in caesium-sputter ion source. The intention was to determine the procedure which would produce the highest intensity negative lithium beams over extended period and with maximum stability. The chemical composition and properties of the samples were analysed using mass-spectrometry, optical microscopy, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Analyses (EDX) and Raman spectroscopy. These analyses showed that the chemical transformations with components resulted from pressing, storage and bake out were qualitatively in agreement with expectations. Intensive negative lithium ion beams > 1 mu A were delivered using cathodes fabricated from materials with multicomponent chemical composition when the following conditions were met: (i) use of components with moderate enthalpy of formation; (ii) low moisture content at final stage of cathode production and (iii) small concentration of water molecules in hydrate phase in the cathode mixture.

【 授权许可】

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