A STUDY OF THE ELECTRON OPTICAL PROPERTIES OF HEMISPHERICAL DEFLECTION ANALYZERS AIMED AT OPTIMIZING THEIR FRINGING FIELD CORRECTION SCHEMES

Sise O.

UNIVERSITY POLITEHNICA OF BUCHAREST SCIENTIFIC BULLETIN-SERIES A-APPLIED MATHEMATICS AND PHYSICS, cilt.77, sa.1, ss.213-222, 2015 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 77 Konu: 1
  • Basım Tarihi: 2015
  • Dergi Adı: UNIVERSITY POLITEHNICA OF BUCHAREST SCIENTIFIC BULLETIN-SERIES A-APPLIED MATHEMATICS AND PHYSICS
  • Sayfa Sayıları: ss.213-222

Özet

First-order focusing characteristic of hemispherical deflection analyzers (HDAs) is limited due to fringing field at the boundaries of the electrodes. In this paper, we present a systematic study of fringing field effects for different ratios of the gap to mean radius in the range of 0.2 <= Delta R/R-m <= 0.6 and compare the performance of some useful designs, i. e., ideal HDA, fringing field HDA, Herzog correction, Jost correction, tilted input beam angle, and biased paracentric configuration for resolution improvement.