Angular Confinement of Field Electron and Ion Emission
作者:
L. W. Swanson,
L. C. Crouser,
期刊:
Journal of Applied Physics
(AIP Available online 1969)
卷期:
Volume 40,
issue 12
页码: 4741-4749
ISSN:0021-8979
年代: 1969
DOI:10.1063/1.1657282
出版商: AIP
数据来源: AIP
摘要:
Three methods of confining the angular dispersion of a field electron beam from 〈100〉 oriented tungsten emitters are investigated; they are (1) thermal‐field buildup, (2) selective work function reduction by zirconium adsorption, and (3) high‐temperature field evaporation. All three methods confine the emission to a beam half‐angle of less than 9° in the dc current range 0.1 to 100 &mgr;A. Method (1) results in a ∼50% reduction in beam voltage. Provided that the vacuum level is good (∼10−10Torr), long and short term current instabilities are negligible for dc current levels below 10 &mgr;A at 300°K for each of the emitter end forms investigated. The angular dispersion and beam voltage of a field ion beam can also be reduced by method (1) as described briefly in this paper.
点击下载:
PDF
(667KB)
返 回