Focusing-deflection system for electronic guns

FIELD: physics.

SUBSTANCE: system comprises a magnetic focusing lens [1] consisting of an excitation winding [2], a magnetic circuit [3], magnetic amorphous alloy rings [4] of a thin tape with the saturation induction not worse than the saturation induction of the magnetic material [3] and non-magnetic gaps [5], a bipolar deflective system of the toroidal type [6], an electron-optical gun axis [7], a beam guide [8], an electron beam crossover plane [9], an electron beam focusing plane [10]. The electron beam generated by the electron gun and the forming system, enters through the beam guide [8] in the focusing-deflection system along the electron-optical axis [7]. When applying current to the excitation coil [2], the magnetic focusing lens [1] carries the crossover of the electron beam in the plane [9] located near the accelerating gap, to the focusing plane [10] on the treated object. The deflection system [6] of the toroidal type at the current supply to its windings, deflects the electron beam within the treatment field according to the predetermined program, and the deflection center is located at the magnetic lens center. The rings [4] of the soft magnetic material shield the magnetic field of the external windings against the deflection system axis [6], and increase the induction amount of the deflection field on the system axis generated by the internal windings. Herewith the alternating rings [4] of the soft magnetic material and the gaps [5] provide a concentration of the focusing system magnetic field on the electron-optical gun axis [7].

EFFECT: extending the scope of the focusing-deflecting system for the implementation of various technological material processings by the electron beam.

5 dwg, 2 tbl

 



 

Same patents:

FIELD: raster electron microscopy; electromagnetic filters for spatial separation of primary and secondary electron beams.

SUBSTANCE: proposed filter has eight sector electrodes disposed within cylinder made of dielectric and nonmagnetic material. Electrodes are made of ferromagnetic material in the form of eight cylindrical segments having separation angle of 30 and 60 degrees and function at the same time as magnetic poles. Four magnetic poles are disposed on outer surface of cylinder at separation angle of 60 and 120 degrees. Round diaphragms with central bore placed on butt-ends of filters are made of conducting ferromagnetic material, one of diaphragms having four or more symmetrically disposed holes for bringing out secondary electron beam. Deviation of secondary electron beams is more than 20 deg. in absence of primary electron beam axis deviation throughout entire length of filter.

EFFECT: minimized aberration of primary electron beam.

1 cl, 2 dwg

The invention relates to electromagnets for deviation and separation of the charged particle beam and can be used for I/o them in the accelerator

FIELD: raster electron microscopy; electromagnetic filters for spatial separation of primary and secondary electron beams.

SUBSTANCE: proposed filter has eight sector electrodes disposed within cylinder made of dielectric and nonmagnetic material. Electrodes are made of ferromagnetic material in the form of eight cylindrical segments having separation angle of 30 and 60 degrees and function at the same time as magnetic poles. Four magnetic poles are disposed on outer surface of cylinder at separation angle of 60 and 120 degrees. Round diaphragms with central bore placed on butt-ends of filters are made of conducting ferromagnetic material, one of diaphragms having four or more symmetrically disposed holes for bringing out secondary electron beam. Deviation of secondary electron beams is more than 20 deg. in absence of primary electron beam axis deviation throughout entire length of filter.

EFFECT: minimized aberration of primary electron beam.

1 cl, 2 dwg

FIELD: physics.

SUBSTANCE: system comprises a magnetic focusing lens [1] consisting of an excitation winding [2], a magnetic circuit [3], magnetic amorphous alloy rings [4] of a thin tape with the saturation induction not worse than the saturation induction of the magnetic material [3] and non-magnetic gaps [5], a bipolar deflective system of the toroidal type [6], an electron-optical gun axis [7], a beam guide [8], an electron beam crossover plane [9], an electron beam focusing plane [10]. The electron beam generated by the electron gun and the forming system, enters through the beam guide [8] in the focusing-deflection system along the electron-optical axis [7]. When applying current to the excitation coil [2], the magnetic focusing lens [1] carries the crossover of the electron beam in the plane [9] located near the accelerating gap, to the focusing plane [10] on the treated object. The deflection system [6] of the toroidal type at the current supply to its windings, deflects the electron beam within the treatment field according to the predetermined program, and the deflection center is located at the magnetic lens center. The rings [4] of the soft magnetic material shield the magnetic field of the external windings against the deflection system axis [6], and increase the induction amount of the deflection field on the system axis generated by the internal windings. Herewith the alternating rings [4] of the soft magnetic material and the gaps [5] provide a concentration of the focusing system magnetic field on the electron-optical gun axis [7].

EFFECT: extending the scope of the focusing-deflecting system for the implementation of various technological material processings by the electron beam.

5 dwg, 2 tbl

Up!