Plasma processing apparatus and methods for removing extraneous material from selected areas on a substrate

• US 20060118239A1
• Filed: 12/03/2004
• Published: 06/08/2006
• Est. Priority Date: 12/03/2004
• Status: Active Grant

• Current Assignee: Nordson Corporation
• Original Assignee: Nordson Corporation
• Inventors: Getty, James D., Tyler, James S., Condrashoff, Robert S.
• Granted Patent: US 7,635,418 B2
• Time in Patent Office: Days
• US Class Current: 156/345.300
• CPC Class Codes: C23F 4/00 Processes for removing metallic material from surfaces, not provided for in group C23F1/00 or C23F3/00
• CPC Class Codes: H01J 37/32623 Mechanical discharge control means
• CPC Class Codes: H01L 21/67069 for drying etching
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

Apparatus and methods for shielding a feature projecting from a first area on a substrate to a plasma while simultaneously removing extraneous material from a different area on the substrate with the plasma. The apparatus includes at least one concavity positioned and dimensioned to receive the feature such that the feature is shielded from the plasma. The apparatus further includes a window through which the plasma removes the extraneous material. The method generally includes removing the extraneous material while shielding the feature against plasma exposure.

Claims

1. A shielding assembly for holding a substrate during treatment with a plasma, the substrate having a first area, a feature projecting from the first area, and a second area covered by an extraneous material, said shielding assembly comprising:

a first member including a concavity positioned and dimensioned to receive the feature and to shield the feature from the plasma; and

a second member including a window for passing the plasma into contact with the extraneous material for removing the extraneous material from the second area with the plasma.

2. The shielding assembly of claim 1 further comprising:

a third member aligning said second member relative to said first member.

3. The shielding assembly of claim 2 wherein said third member has a recess, and said second member is positioned inside said recess.

4. The shielding assembly of claim 1 wherein said first and second members are formed from an electrically-conductive material, and said first and second members have a contacting relationship adequate for electrical conduction.

5. The shielding assembly of claim 1 wherein said concavity has a perimeter that contacts the first area of the substrate about the feature, the contact between said concavity and the first area effective to shield the feature from the plasma.

6. The shielding assembly of claim 1 wherein said window includes first and second side edges and a plurality of cross members extending between said first and second side edges, said cross members being positioned such that the second area is exposed.

7. The shielding assembly of claim 1 wherein said second member is positioned relative to said first member such that the substrate is located between said first and second members, said concavity is positioned on one side of the substrate to cover the feature, and said window is positioned on an opposite side of the substrate to expose the second area.

8. A processing system for treating a substrate with a plasma, the substrate having a first area, a feature projecting from the first area, and a second area covered by an extraneous material, said processing system comprising:

a vacuum chamber enclosing a processing space capable of being evacuated to a partial vacuum;

an electrode positioned in said processing space;

a gas port defined in said vacuum chamber for admitting a process gas into said processing space;

a power supply electrically coupled with said electrode, said power supply operative for converting the process gas to the plasma; and

a shielding assembly holding the substrate at a processing position in said processing space, said shielding assembly including a first member with a concavity positioned and dimensioned to receive the feature and to shield the feature from the plasma and a second member with a window for passing the plasma into contact with the extraneous material for removing the extraneous material from the second area with the plasma.

9. The processing system of claim 8 wherein said shielding assembly is positioned on said electrode.

10. The processing system of claim 9 wherein said first member is oriented such that said at least one concavity faces away from said electrode.

11. The processing system of claim 8 wherein said shielding assembly is electrically coupled with said electrode.

12. The processing system of claim 8 wherein said shielding assembly further comprises:

a third member aligning said second member relative to said first member.

13. The processing system of claim 12 wherein said third member has a recess, and said second member is positioned inside said recess.

14. The processing system of claim 8 wherein said first and second members are formed from an electrically-conductive material, and said first and second members have a contacting relationship adequate for electrical conduction.

15. The processing system of claim 8 wherein said concavity has a perimeter that contacts the first area of the substrate about the feature, the contact between said concavity and the first area effective to shield the feature from the plasma.

16. The processing system of claim 8 wherein said window includes first and second side edges and a plurality of cross members extending between said first and second side edges, said cross members being positioned relative to the substrate such that the area is exposed.

17. The processing system of claim 8 wherein said second member is positioned relative to said first member such that the substrate is located between said first and second members, said concavity is positioned on one side of the substrate to cover the feature, and said window is positioned on an opposite side of the substrate to expose the second area.

18. A method for plasma treating a substrate in a processing space defined inside a vacuum chamber, the substrate having a first area, a feature projecting from the first area, and a second area covered by an extraneous material, the method comprising:

placing the substrate in the processing space of the vacuum chamber;

generating a plasma in the processing space;

covering the first area of the substrate with a shielding assembly having a concavity configured to receive and shield the feature from the plasma; and

exposing the second area to reactive species from the plasma effective for removing the extraneous material from the second area.

19. The method of claim 18 wherein the mask contacts the first area about the perimeter of the concavity.

20. The method of claim 18 wherein the substrate has opposite first and second sides, the first area is on the first side of the substrate, and the second area is on the second side of the substrate.

21. The method of claim 20 wherein placing the substrate in the processing space further comprises:

placing the shielding assembly and the substrate on a powered electrode used to generate the plasma in the processing space; and

orienting the substrate so that the second side faces away from the powered electrode.

22. The method of claim 18 wherein exposing the second area to reactive species from the plasma further comprises:

positioning a window of the shielding assembly over the second area so that the second area is exposed to the reactive species.

23. The method of claim 22 wherein placing the substrate in the processing space further comprises:

placing the shielding assembly and the substrate on a powered electrode used to generate the plasma in the processing space; and

orienting the substrate so that the second area faces away from the powered electrode.

24. The method of claim 18 wherein placing the substrate in the processing space further comprises:

placing the shielding assembly and the substrate on a powered electrode used to generate the plasma in the processing space.