Sputtering coating of protective layer for charged particle beam processing

• US 7,675,049 B2
• Filed: 02/14/2007
• Issued: 03/09/2010
• Est. Priority Date: 02/15/2006
• Status: Active Grant

• Current Assignee: FEI Company (Thermo Fisher Scientific Incorporated)
• Original Assignee: FEI Company (Thermo Fisher Scientific Incorporated)
• Inventors: Schmidt, Michael, Blackwood, Jeff
• Primary Examiner(s): Berman; Jack I
• Assistant Examiner(s): IPPOLITO, NICOLE MARIE
• Application Number:
  US11/706,053
• Publication Number:
  US 20080073587A1
• Time in Patent Office: 1,119 Days
• Field of Search: 250/306, 250/307, 250/309, 250/310, 250/311, 250/492.1, 250/492.2, 250/492.21, 250/492.3, 250/492.22, 430/296, 430/297, 430/298, 430/299
• US Class Current: 250/492.21
• CPC Class Codes: B23K 15/0086 welding for purposes other than joining, e.g. built-up welding
• CPC Class Codes: B23K 15/06 within a vacuum chamber B23K15/04 takes precedence
• CPC Class Codes: B23K 2101/40 Semiconductor devices
• CPC Class Codes: C23C 14/30 by electron bombardment
• CPC Class Codes: H01J 37/302 Controlling tubes by external information, e.g. programme control H01J37/304 takes precedence
• CPC Class Codes: H01J 37/3056 for microworking, e.g. etching of gratings, trimming of electrical components trimming of resistors H01C17/22

Abstract

A coating is applied to a work piece in a charged particle beam system without directing the beam to work piece. The coating is applied by sputtering, either within the charged particle beam vacuum chamber or outside the charged particle beam vacuum chamber. In one embodiment, the sputtering is performed by directing the charged particle beam to a sputter material source, such as a needle from a gas injection system. Material is sputtered from the sputter material source onto the work piece to form, for example, a protective or conductive coating, without requiring the beam to be directed to the work piece, thereby reducing or eliminating damage to the work piece.

Claims

1. A method for forming a coating on a work piece in a vacuum chamber of a charged particle beam system having a particle beam source and a work piece support, comprising:

inserting a work piece into the vacuum chamber of the charged particle beam system and onto the work piece support;

providing in the vacuum chamber a sputter material source, the sputter material source being positioned between the particle beam source and the work piece;

directing a focused or shaped charged particle beam toward the sputter material source so that the charged particle beam impacts the surface of the sputter material source to sputter material from the sputter material source onto an area of the work piece to form a layer of material on the area of work piece, thereby avoiding damage to the work piece; and

directing the charged particle beam toward the area of the work piece to process or form an image of the work piece.

2. The method of claim 1 in which directing a focused or shaped charged particle beam toward the sputter material source and directing the charged particle beam toward the area of work piece to process form an image of the work piece occur in the same vacuum chamber, without the work piece being removed from the vacuum chamber between the steps of directing the charged particle beam towards the sputter source and directing the charged particle toward the area of work piece, thereby allowing a protective or conductive layer to be applied and a work piece with the protective or conductive layer to be processed or imaged without removing the work piece from the vacuum chamber.

3. The method of claim 1 in which directing a focused or shaped charged particle beam toward an area of the work piece to process an area the work piece includes directing an electron beam toward the work piece to form an image of the area of the work piece using secondary or transmitted electrons.

4. The method of claim 1 in which directing a focused or shaped charged particle beam toward an area of the work piece to process an area of the work piece includes directing a focused ion beam toward the area of work piece to micromachine the work piece or to deposit material onto the work piece.

5. The method of claim 1 in which directing a focused or shaped charged particle beam toward the sputter material source so that the charged particle beam impacts the surface of the sputter material source includes directing a focused or shaped charged particle beam toward a gas injection system nozzle or material coated or material supported on a gas injection nozzle so that the charged particle beam impacts the surface of the gas injection system nozzle or material coated or material supported on a gas injection nozzle.

6. The method of claim 1 in which directing the charged particle beam toward the sputter material source includes directing the charged particle beam toward a source of material to form a protective or conductive layer on the work piece.

7. The method of claim 1 in which directing a focused or shaped charged particle beam toward the sputter material source includes directing the charged particle beam toward the sputter material source to sputter tungsten, chromium, titanium, copper, or aluminum material from the sputter material source onto the work piece.

8. The method of claim 1 in which directing a focused or shaped charged particle beam toward the sputter material source so that the charged particle beam impacts the surface of the sputter material source to sputter material from the sputter material source onto an area of the work piece to form a layer on the area of work piece includes directing a focused or shaped charged particle beam toward the sputter material source so that the charged particle beam impacts the surface of the sputter material source to sputter material from the sputter material source onto a portion of a wafer or other work piece smaller than the entire surface of the wafer or other work piece.

9. A charged particle system including a memory storing computer instructions to perform the steps of claim 1.

10. A method of charged particle beam processing, comprising:

placing a work piece in the vacuum chamber of the charged particle beam system;

sputtering a coating onto a work piece using a focused or shaped charged particle beam;

then, without removing the work piece from the vacuum chamber, processing the work piece using the charged particle beam to etch material from the work piece, deposit material onto the work piece, or to form an image of the work piece, the sputter coating protecting features on the work piece surface during charged particle beam processing.

11. The method of claim 10 in which sputtering a coating onto a work piece includes sputtering a coating onto a portion of a wafer or other work piece smaller than the entire surface of the wafer or other work piece.

12. The method of claim 10 in which sputtering a coating onto a work piece includes directing an ion beam to a sputter material source to sputter material from the source onto the work piece.

13. The method of claim 10 in which processing the work piece using the charged particle beam includes directing the charged particle beam toward the work piece to alter the shape of the work piece.

14. The method of claim 13 which directing the charged particle beam toward the work piece to alter the shape of the work piece includes milling the work piece to expose a cross section.

15. The method of claim 13 in which directing the charged particle beam toward the work piece to alter the shape of the work piece includes milling the work piece to extract a sample from the work piece.

16. The method of claim 14 in further comprising directing an electron beam toward the exposed cross section to form an image of the cross section using scanning electron microscopy and in which the work piece remains in the same vacuum chamber for sputtering, for processing by the focused or shaped charged particle beam, and for directing the electron beam.

17. The method of claim 10 in which sputtering a coating onto a work piece includes using a plasma to sputter material from the source onto the work piece.

18. A charged particle system including a memory storing computer instructions to perform the step of claim 10.

19. A charged particle beam system, comprising:

a charged particle source;

charged particle beam optical components for forming the charged particles into a focused or shaped beam for processing a work piece positioned within a vacuum chamber;

multiple sputter material sources for sputtering different materials, the multiple sputtering material sources positioned within a vacuum chamber;

a manipulator for moving the sputter material sources into a first position between the charged particle beam source and the work piece in which the charged particle beam can be directed to the sputter material source to sputter material from the sputter material source onto the work piece to form a coating on the work piece without directing the charged particle beam toward the work piece and to a second position in which the sputter material source is not in the beam path to allow the charged particle beam can be directed to impact the work piece;

a memory storing computer instructions to perform the steps of;

directing the charged particle beam toward the sputter material source so that the charged particle beam impacts the surface of the sputter material source to sputter material from the sputter material source onto an area of the work piece to form a protective layer on the area of work piece, thereby avoiding damage to the work piece; and

directing the charged particle beam toward the area of the work piece to process or form an image of the work piece after the protective layer has be formed.