Patent ID: 8373137
Filing Date: 2013-02-12
Classification: H01J

Abstract:
1. An energy-selecting apparatus for decreasing an energy range of an electron beam incident on a sample, said apparatus comprising: (a) one or more energy-dispersing elements disposed in first half of said apparatus and producing an energy-dispersed electron beam; (b) one or more magnifying optical elements disposed in said first half of said apparatus, said optical elements magnifying energy dispersion of said energy-dispersed electron beam; (c) an energy-selecting slit disposed at or near mid-plane of said apparatus, said slit intercepting electrons of energies outside a central pass-band of energies and thus decreasing range of energies of said energy-dispersed electron beam; (d) one or more de-magnifying optical elements disposed after said energy-selecting slit in second half of said apparatus, said optical elements de-magnifying said energy dispersion of said energy-dispersed electron beam; (e) one or more energy-undispersing elements disposed in said second half of said apparatus, said energy-undispersing elements cancelling said energy dispersion of said electron beam; (f) optical elements disposed after said energy-undispersing elements in said second half of said apparatus, said optical elements focusing said electron beam onto a sample, whereby said range of energies of said electron beam is decreased by said energy-selecting slit, said energy dispersion is subsequently canceled, and said electron beam of decreased range of energies is focused into an electron probe on said sample.