Particle-optical systems and arrangements and particle-optical components for such systems and arrangements

Patent metadata

Field	Value
Publication number	US-9653254-B2
Application number	US-201615016743-A
Country	US
Kind code	B2
Filing date	Feb 5, 2016
Priority date	Sep 28, 2010
Publication date	May 16, 2017
Grant date	May 16, 2017

Abstract

The present invention concerns a charged-particle multi-beamlet system that comprises a source of charged particles ( 301 ); a first multi-aperture plate ( 320 ) having plural apertures disposed in a charged particle beam path of the system downstream of the source; a first multi-aperture selector plate ( 313 ) having plural apertures; a carrier ( 340 ), wherein the first multi-aperture selector plate is mounted on the carrier; and an actuator ( 350 ) configured to move the carrier such that the first multi-aperture selector plate is disposed in the charged particle beam path of the system downstream of the source in a first mode of operation of the system, and such that the first multi-aperture selector plate is disposed outside of the charged particle beam path in a second mode of operation of the system. The source, the first multi-aperture plate and the carrier of the system are arranged such that a first number of charged particle beamlets is generated at a position downstream of both the first multi-aperture plate and the first multi-aperture selector plate in the first mode of operation, and that a second number of charged particle beamlets is generated at the position in the second mode of operation, wherein the first number of beamlets differs from the second number of beamlets.

First claim

The invention claimed is:

1. A charged-particle multi-beamlet system comprising:
a source of charged particles;
a multi-aperture plate disposed in a charged particle beam path of the system downstream of the source, wherein the multi-aperture plate comprises plural apertures forming a first multi-aperture array with apertures arranged at positions of a basic pattern;
a multi-aperture selector plate having a main face and plural apertures forming plural multi-aperture arrays comprising at least a second and a third multi-aperture array, wherein apertures of the second and the third multi-aperture array are arranged at positions of the basic pattern;
a carrier, wherein the multi-aperture selector plate is mounted on the carrier;
an actuator configured to move the carrier such that the multi-aperture selector plate is disposed in the charged particle beam path of the system downstream of the source and can be displaced in a direction parallel to its main face;
wherein the source, the first multi-aperture plate and the carrier are arranged such that a first number of charged particle beamlets is generated at a position downstream of both the first multi-aperture plate and the multi-aperture selector plate; and
wherein the apertures of the multi-aperture selector plate have diameters, and wherein the diameters of the apertures of the third multi-aperture array are greater than the diameters of the apertures of the second multi-aperture array.

2. The charged-particle multi-beamlet system of claim 1 , wherein the actuator is configured to insert, in a first mode of operation, the second multi-aperture array into the charged particle beam path and to insert, in a second mode of operation, the third multi-aperture array into the charged particle beam path.

3. The charged-particle multi-beamlet system according to claim 1 , further comprising a focusing lens disposed in a beam path downstream of both the multi-aperture plate and the multi-aperture selector plate.

4. The charged-particle multi-beamlet system according to claim 3 , further comprising a stage for mounting an object in an object plane disposed downstream of the focusing lens.

5. The charged-particle multi-beamlet system according to claim 1 , further comprising a first voltage supply configured to supply a first voltage to the multi-aperture plate such that charged particle beamlets traversing the apertures of the multi-aperture plate each have a beamlet focus at a distance downstream of the multi-aperture plate.

6. The charged-particle multi-beamlet system according to claim 4 , wherein the focusing lens is configured such that the beamlet foci are imaged onto the object plane.

7. The charged-particle multi-beamlet system according to claim 3 , further comprising a field-separating electrode having an aperture disposed in the charged particle beam path downstream of the focusing lens and upstream of the object plane.

8. The charged-particle multi-beamlet system according to claim 7 , wherein the diameter of the aperture of the field-separating electrode is smaller than 2.0 mm.

9. The charged-particle multi-beamlet system according to claim 7 , further comprising:
a second voltage supply configured to supply a second voltage to the field-separating electrode; and
a third voltage supply configured to supply a third voltage to the object.

10. The charged-particle multi-beamlet system according to claim 1 , wherein the basic pattern includes at least one of a hexagonal pattern and a rectangular pattern.

11. The charged-particle multi-beamlet system according to claim 3 , wherein the focusing lens comprises magnetic pole pieces and at least one coil for generating a focusing magnetic field between the pole pieces.

12. The charged-particle multi-beamlet system according to claim 3 , wherein the focusing lens comprises at least one pair of electrodes and a voltage supply to generate a focusing electric field between the pair of electrodes.

13. A charged-particle multi-beamlet system comprising:
a source of charged particles;
a multi-aperture plate disposed in a charged particle beam path of the system downstream of the source, wherein the multi-aperture plate comprises plural apertures forming a first multi-aperture array with apertures arranged at positions of a basic pattern;
a first multi-aperture selector plate having a main face and plural apertures forming a second multi-aperture array wherein apertures of the second multi-aperture array are arranged at positions of the basic pattern;
a second multi-aperture selector plate having a main face and plural apertures forming a third multi-aperture array wherein apertures of the third multi-aperture array are arranged at positions of the basic pattern;
a carrier configured so that the first multi-aperture selector plate and the second multi-aperture selector plate can be mounted on the carrier;
an actuator configured to move the carrier such that, in a first mode of operation, the first multi-aperture selector plate is disposed in the charged particle beam path of the system downstream of the source and, in a second mode of operation, the second multi-aperture selector plate is disposed in the charged particle beam path of the system downstream of the source;
wherein the source, the first multi-aperture plate and the carrier are arranged such that a first number of charged particle beamlets is generated at a position downstream of both the first multi-aperture plate and the multi-aperture selector plate; and
wherein the apertures of the first multi-aperture selector plate and the second multi-aperture selector plate have diameters, and wherein the diameters of the apertures of the third multi-aperture array are greater than the diameters of the apertures of the second multi aperture array.

14. The charged-particle multi-beamlet system according to claim 13 , further comprising a focusing lens disposed in a beam path downstream of both the multi-aperture plate and the multi-aperture selector plate.

15. The charged-particle multi-beamlet system according to claim 14 , further comprising a stage for mounting an object in an object plane disposed downstream of the focusing lens.

16. The charged-particle multi-beamlet system according to claim 13 , further comprising a first voltage supply configured to supply a first voltage to the multi-aperture plate such that charged particle beamlets traversing the apertures of the multi-aperture plate each have a beamlet focus at a distance downstream of the multi-aperture plate.

17. The charged-particle multi-beamlet system according to claim 15 , wherein the focusing lens is configured such that the beamlet foci are imaged onto the object plane.

18. The charged-particle multi-beamlet system according to claim 17 , further comprising a field-separating electrode having an aperture disposed in the charged particle beam path downstream of the focusing lens and upstream of the object plane.

19. The charged-particle multi-beamlet system according to claim 18 , further comprising a second voltage supply configured to supply a second voltage to the field-separating electrode and a third voltage supply configured to supply a third voltage to the object.

20. The charged-particle multi-beamlet system according to claim 13 , wherein the basic pattern includes at least one of a hexagonal pattern and a rectangular pattern.

21. The charged-particle multi-beamlet system according to claim 14 , wherein the focusing lens comprises magnetic pole pieces and at least one co

Assignees

• Applied Materials Israel Ltd
• Zeiss Carl Microscopy Gmbh

Inventors

• Zeidler Dirk
• Kemen Thomas
• Pascal Anger
• Casares Antonio
• Riedesel Christof

Classifications

• H01J2237/0492

  Lens systems · CPC title

• B82Y10/00 Primary

  Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic · CPC title

• H01J37/21

  Means for adjusting the focus · CPC title

• H01J37/28

  with scanning beams {(H01J37/268, H01J37/292, H01J37/2955 take precedence)} · CPC title

• H01J2237/0458

  movable, i.e. for changing between differently sized apertures · CPC title