COLUMN SIMULTANEOUSLY FOCUSING A PARTICLE BEAM AND AN OPTICAL BEAM

• US 20080111084A1
• Filed: 10/31/2007
• Published: 05/15/2008
• Est. Priority Date: 03/20/2000
• Status: Active Grant

• Current Assignee: DCG Systems Incorporated (Thermo Fisher Scientific Incorporated)
• Original Assignee: DCG Systems Incorporated (Thermo Fisher Scientific Incorporated)
• Inventors: Sudraud, Pierre, Bouchet, Patrick, Benas-Sayag, Gerard, Corbin, Antoine
• Granted Patent: US 7,573,050 B2
• Time in Patent Office: Days
• US Class Current: 250/396R
• CPC Class Codes: G02B 17/082 using three curved mirrors G02B17/0864, G02B17/0896 take precedence
• CPC Class Codes: H01J 2237/121 characterised by shape
• CPC Class Codes: H01J 2237/2482 Optical means
• CPC Class Codes: H01J 2237/31749 Focused ion beam
• CPC Class Codes: H01J 37/12 electrostatic
• CPC Class Codes: H01J 37/228 whereby illumination and light collection take place in the same area of the discharge
• CPC Class Codes: H01J 37/304 Controlling tubes by information coming from the objects or from the beam, e.g. correction signals
• CPC Class Codes: H01J 37/3056 for microworking, e.g. etching of gratings, trimming of electrical components trimming of resistors H01C17/22

Abstract

Column for simultaneously producing a focused particle beam and a focused light beam and method for treating a sample using the column. The column has lateral walls, an input electrode having a particle aperture for emitting a particle beam, an electrostatic lens, an optical focusing device within the lens, and a deflection optical mirror. The method comprises locating the sample below the column, passing the particle beam through entry aperture and exit aperture of the lens to be focused on a selected location on the sample, and injecting an optical beam into the lens through the entry aperture. The lens incorporates convex and concave optical mirrors. The optical beam is injected into the lens to reflect from the convex optical mirror towards the concave optical mirror and then reflect from the concave optical mirror to exit from the exit aperture to be focused on the selected location on the sample.

Claims

1. A method for treating a sample by means using a column combining charged particle beam and an optical beam, comprising:

providing a column having an electrostatic lens comprising an entry aperture at a top section and an exit aperture at a bottom section, the electrostatic lens incorporating a convex optical mirror and a concave optical mirror;

locating a sample below the column;

passing a particle beam through the entry aperture and exit aperture of the electrostatic lens so as to be focused on a selected location on the sample;

injecting an optical beam into the electrostatic lens through the entry aperture, so as to reflect from the convex optical mirror towards the concave optical mirror and then reflect from the concave optical mirror to exit from the exit aperture so as to be focused on the selected location on the sample.

2. The method of claim 1, wherein injecting optical beam comprises injecting one of a UV light, an infra-red light and a laser beam.

3. The method of claim 1, further comprising investigating the effect of the particle beam on the sample by information supplied by the optical beam.

4. The method of claim 1, wherein the treating comprises one of etching, engraving, and assisted deposition.

5. The method of claim 4, wherein the treating further comprises providing chemical assistance.

6. The method of claim 1, further comprising passing the optical beam through a conductive transparent window after the optical beam has passed the exit aperture.

7. The method of claim 6, further comprising passing the particle beam through a metallic inset situated at the center of the transparent window.

8. The method of claim 1, wherein injecting an optical beam into the electrostatic lens through the entry aperture comprises injecting the optical beam coaxially to the particle beam.

9. A method for etching a sample, comprising:

situating a sample under a column;

energizing the column to produce a particle beam;

injecting an optical beam into the column so as to propagate coaxially with the particle beam;

heating the sample by focusing the optical beam on a selected area on the sample;

etching the sample by focusing the particle beam onto the selected area to bombard the selected area with charged particles.

10. A column for simultaneously producing a focused particle beam and a focused light beam, the column comprising:

lateral walls;

an input electrode situated within the lateral walls and having a particle aperture for emitting a particle beam;

an electrostatic lens situated within the lateral walls and positioned to receive the particle beam from the particle aperture of the input electrode;

an optical focusing device positioned within the electrostatic lens, the optical focusing device having a convex mirror and a concave mirror, the convex mirror having a through-hole at the center thereof allowing passage of the particle beam there-through, the convex mirror facing the concave mirror;

a deflection optical mirror situated between the input electrode and the concave mirror and having an aperture for passage of the particle beam, the deflection mirror positioned to deflect optical beam towards the convex mirror through the through-hole of the concave mirror.

11. The column of claim 10, further comprising an optically transparent window for transmitting the light beam after the light beam reflects from the concave mirror.

12. The column of claim 11, further comprising an output electrode is centrally located within the transparent window.

13. The column of claim 12, wherein the transparent window is electrically conductive.

14. The column of claim 13, wherein the output electrode and the transparent window are coupled to the same electrical potential.

15. The column of claim 14, wherein the electrical potential is ground reference.

16. The column of claim 12, wherein the output electrode comprises a metallic insert projecting from the surface of the transparent window.

17. The column of claim 12, wherein the transparent window comprises a layer of indium tin oxide.

18. The column of claim 10, further comprising a particle beam output aperture and a coaxially positioned optical beam output aperture.

19. The column of claim 18, wherein the diameter of the particle beam output aperture differs from the diameter of the optical beam output aperture.

20. The column of claim 19, wherein the optical beam aperture comprises a bulk material transparent to photons and the particle beam aperture comprises a through-hole in the bulk material.