Particle beam system having a mirror corrector

A particle beam system having an optical axis and comprising:

• a particle source for emitting particles along a beam path;
• an objective lens defining a diffraction plane and being mounted on said beam path downstream of said particle source;
• a mirror corrector unit including an electrostatic mirror disposed on said beam path between said particle source and said objective lens;
• said mirror corrector unit further including a magnetic beam deflector disposed on said beam path so as to be disposed between said particle source and said electrostatic mirror and between said electrostatic mirror and said objective lens;
• said magnetic beam deflector being free of dispersion for each single passthrough of said particles and said magnetic beam deflector including a plurality of quadrupoles which are so determined that on the entire course of said beam path between a first-time exit from said magnetic beam deflector and said objective lens, a maximum of two planes occur conjugated to said diffraction plane of said objective lens;
• said magnetic beam deflector having an entry end and a second-time exit therefrom and said magnetic beam deflector defining a first symmetry plane between said entry end and said first-time exit and a second symmetry plane between said first-time exit and said second-time exit;
• and,
• said first and second symmetry planes intersecting with said optical axis and said magnetic beam deflector being sufficiently telescopic so as to permit component beams which originate at the intersections of said symmetry planes with said optical axis to run parallel or slightly convergent outside of said magnetic beam deflector.

A particle beam system comprising:

• a particle source for emitting particles along a beam path;
• an objective lens defining a diffraction plane and being mounted on said beam path downstream of said particle source;
• a mirror corrector unit including an electrostatic mirror disposed on said beam path between said particle source and said objective lens;
• said mirror corrector unit further including a magnetic beam deflector disposed on said beam path so as to be disposed between said particle source and said electrostatic mirror and between said electrostatic mirror and said objective lens;
• said magnetic beam deflector being free of dispersion for each single passthrough of said particles and said magnetic beam deflector including a plurality of quadrupoles which are so determined that on the entire course of said beam path between a first-time exit from said magnetic beam deflector and said objective lens, a maximum of two planes occur conjugated to said diffraction plane of said objective lens;
• a first field lens between said particle source and said magnetic beam deflector and a second field lens between said magnetic beam deflector and said objective lens;
• said field lenses each being an immersion lens with which the kinetic energy of the particles is increased before entering into said magnetic beam deflector;
• and
• each of said field lenses being an immersion lens with which the kinetic energy of the particles is reduced after exiting from said magnetic beam deflector.