INTEGRATED LIGHT OPTICS AND GAS DELIVERY IN A CHARGED PARTICLE LENS

• US 20150380205A1
• Filed: 06/30/2014
• Published: 12/31/2015
• Est. Priority Date: 06/30/2014
• Status: Active Grant

• Current Assignee: FEI Company (Thermo Fisher Scientific Incorporated)
• Original Assignee: FEI Company (Thermo Fisher Scientific Incorporated)
• Inventors: Parker, N. William, Botman, Aurelien Philippe Jean Maclou, Randolph, Steven, Chandler, Clive, Utlaut, Mark, Straw, Mark, Filevich, Jorge
• Granted Patent: US 9,478,390 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01J 2237/006 Details of gas supplies, e.g. in an ion source, to a beam line, to a specimen or to a workpiece, H01J37/3244 takes precedence; environmental cells for electron microscopes H01J2237/2003; microscopes with environmental specimen chamber H01J2237/2608
• CPC Class Codes: H01J 2237/31749 Focused ion beam
• CPC Class Codes: H01J 37/12 electrostatic
• CPC Class Codes: H01J 37/228 whereby illumination or light collection take place in the same area of the discharge

Abstract

A method and apparatus for directing light or gas or both to a specimen positioned within about 2 mm from the lower end of a charged particle beam column The charged particle beam column assembly includes a platform defining a specimen holding position and has a set of electrostatic lenses each including a set of electrodes. The assembly includes a final electrostatic lens that includes a final electrode that is closest to the specimen holding position. This final electrode defines at least one internal passageway having a terminus that is proximal to and directed toward the specimen holding position.

Claims

1. A charged particle beam column assembly, comprising:

a) a platform defining a specimen holding position;

b) an electrostatic lens comprising a set of electrodes including a final electrode that is closest to the specimen holding position; and

c) wherein said final electrode defines at least one internal passageway transverse to the optical axis of the charged particle beam column having a terminus that is proximal to and directed toward the specimen holding position.

2. The assembly of claim 1, wherein said internal passageway is a light pathway and has an additional terminus that houses a light detector.

3. The assembly of claim 1, wherein said internal passageway is a first light pathway and wherein said final electrode defines a second light pathway in addition to said first light pathway.

4. The assembly of claim 3, wherein said first light pathway terminates in a light source and said second light pathway terminates in a light detector.

5. The assembly of claim 1, wherein said final electrode is made of metal and wherein said internal passageway takes the form of a tubular void space in the metal.

6. The assembly of claim 5, wherein the metal is a titanium alloy.

7. The assembly of claim 5, wherein the surfaces of the void space are polished to increase reflection.

8. The assembly of claim 1, wherein a light pipe extends through said internal passageway.

9. The assembly of claim 1, wherein said internal passageway is a gas pathway and includes an additional terminus that is connected to a gas source.

10. The assembly of claim 9, wherein said internal passageway is a first gas pathway and wherein said final electrode defines a second gas pathway in addition to said first gas pathway.

11. The assembly of claim 10, wherein said first gas pathway terminates in a gas source and said second gas pathway terminates in a gas detector.

12. The assembly of claim 10, wherein said first gas pathway terminates in a first gas source and a said second gas pathway terminates in a second gas source.

13. The assembly of claim 1, wherein said internal passageway is both a gas pathway and a light pathway and includes a terminus that communicates with both a gas source and a light source.

21. The charged particle beam column assembly of claim 1 in which the final electrostatic lens is positioned within about 2 mm of a specimen surface.

22. The charged particle beam column assembly of claim 2 in which the light passageway is oriented transverse to the axis of the charged particle beam.

23. The charged particle beam column assembly of claim 2 in which the light passageway is configured so that the light is reflected multiple as it traverse the passageway.

14. A method of directing light to a predetermined specimen position that is so close to a plate electrode that no oblique pathway exists under the plate electrode to a viable light source position, comprising:

a) providing a light path to the predetermined specimen position through the plate electrode that is so close to a plate electrode that no oblique pathway exists under the plate electrode to a viable light source position; and

b) emitting light into the light path.

15. The method of claim 14, wherein an additional light path is provided to the predetermined specimen position and wherein the method further includes receiving light from the specimen through the additional light path.

16. The method of claim 14, wherein said light path is an interior void having polished surfaces, and wherein said light reflects from said polished surfaces as it travels to said specimen.

17. The method of claim 14, wherein the final electrode is made of a titanium alloy.

18. The method of claim 14, wherein at least one additional light path is provided and wherein light is emitted into the at least one additional light path.

19. A method of directing a gas to a predetermined specimen position that is so close to a plate electrode through which a charged particle beam passes that no oblique pathway exists under the plate electrode to a viable light source position, comprising:

a) providing a gas pathway through the plate electrode to the predetermined specimen position and transverse to the axis of the charged particle beam; and

b) emitting a gas into the gas pathway.

20. The method of claim 19, wherein the gas pathway is a first gas pathway and wherein the gas is a first gas, and further wherein a second gas pathway is provided through the plate electrode to the predetermined specimen position and a second gas is passed through the second gas pathway.