US 7,321,124 B2
Corrector for correcting first-order chromatic aberrations of the first degree
Harald Rose, Darmstadt (Germany)
Assigned to Carl Zeiss NTS GmbH, Oberkochen (Germany)
Filed on Jan. 03, 2006, as Appl. No. 11/322,238.
Application 11/322238 is a continuation of application No. 10/927119, filed on Aug. 27, 2004, granted, now 7,012,262.
Application 10/927119 is a continuation of application No. 10/309262, filed on Dec. 04, 2002, granted, now 6,784,437.
Claims priority of application No. 101 59 454 (DE), filed on Dec. 04, 2001.
Prior Publication US 2006/0102848 A1, May 18, 2006
Int. Cl. H01J 1/50 (2006.01); G01N 23/00 (2006.01); H01J 3/14 (2006.01)
U.S. Cl. 250—396ML  [250/396 R; 250/311] 15 Claims
OG exemplary drawing
 
1. A corrector for correcting aberrations of an electron optical system, the corrector comprising:
a first subsystem including a first plurality of quadrupoles generating quadrupole fields and at least one octopole;
a second subsystem including a second plurality of quadrupoles generating quadrupole fields and at least one octopole;
said first subsystem defining an entrance side of said corrector and said second subsystem defining an exit side of said corrector;
said first and second quadrupole systems conjointly imaging a first nodal plane on said entrance side of said corrector into a second nodal plane on said exit side of said corrector; and,
said at least one octopole of said first subsystem and said at least one octopole of said second subsystem being arranged in astigmatic intermediate image planes of said first nodal plane between said first and said second nodal planes.