Apparatus and method for reactive atom plasma processing for material deposition

• US 20040200802A1
• Filed: 06/27/2003
• Published: 10/14/2004
• Est. Priority Date: 11/07/2001
• Status: Active Grant

• Current Assignee: Imreal Enterprises, LLC
• Original Assignee: Rapt Industries, Inc.
• Inventors: Carr, Jeffrey W.
• Granted Patent: US 7,311,851 B2
• Time in Patent Office: Days
• US Class Current: 216/67
• CPC Class Codes: C23C 16/0245 by etching with a plasma
• CPC Class Codes: C23C 16/047 using irradiation by energy or particles
• CPC Class Codes: C23C 16/513 using plasma jets
• CPC Class Codes: H01J 37/32376 Scanning across large workpieces
• CPC Class Codes: H01L 21/31051 Planarisation of the insulating layers H01L21/31058 takes precedence
• CPC Class Codes: H05H 1/30 using applied electromagnetic fields, e.g. high frequency or microwave energy H05H1/28 takes precedence

Abstract

Reactive atom plasma processing can be used to shape, polish, planarize, and clean surfaces of difficult materials with minimal subsurface damage. The apparatus and methods use a plasma torch, such as a conventional ICP torch. The workpiece and plasma torch are moved with respect to each other, whether by translating and/or rotating the workpiece, the plasma, or both. The plasma discharge from the torch can be used to shape, planarize, polish, clean and/or deposit material on the surface of the workpiece, as well as to thin the workpiece. The processing may cause minimal or no damage to the workpiece underneath the surface, and may involve removing material from, and/or redistributing material on, the surface of the workpiece.

This description is not intended to be a complete description of, or limit the scope of, the invention. Other features, aspects, and objects of the invention can be obtained from a review of the specification, the figures, and the claims.

Claims

1. A method for shaping a surface of a workpiece, comprising:

translating at least one of a workpiece and a plasma torch; and

using reactive atom plasma processing to add material to the surface of the workpiece and modify the surface with the discharge from the plasma torch.

2. A method according to claim 1, wherein:

the step of using reactive plasma processing to modify the surface of the workpiece further includes modifying the surface of the workpiece by at least one of etching, polishing, cleaning, planarizing, and removing material from the surface.

3. A method according to claim 1, further comprising:

altering the chemistry of the surface of the workpiece with the plasma.

4. A method according to claim 1, wherein:

the step of using reactive plasma processing to shape the surface of the workpiece causes minimal or no damage to the workpiece underneath the surface.

5. A method according to claim 1, further comprising:

rotating the workpiece with respect to the plasma torch.

6. A method according to claim 1, further comprising:

creating a reactive species in the plasma.

7. A method according to claim 1, further comprising:

placing a precursor in a central channel of the plasma torch.

11. A method according to claim 1, further comprising:

controlling the mass flow of a precursor into the plasma from between about 0 ml/min to about 2,000 ml/min.

12. A method according to claim 1, further comprising:

controlling the mass flow of a precursor into the plasma from between about 0 ml/min to about 50,000 ml/min.

13. A method according to claim 1, further comprising:

selecting a concentration of precursor to be introduced into a central channel of the plasma.

14. A method according to claim 1, further comprising:

introducing a plasma gas through an outer tube of the plasma torch.

15. A method according to claim 1, further comprising:

coupling energy to the discharge in an annular region of the plasma torch.

16. A method according to claim 1, further comprising:

introducing an auxiliary gas through a second of three concentric tubes in the plasma torch.

17. A method according to claim 1, further comprising:

using an auxiliary gas to keep hot plasma away from a central channel of the plasma torch.

18. A method according to claim 1, further comprising:

using an auxiliary gas to adjust the position of a discharge.

20. A method according to claim 1, further comprising:

introducing a plasma gas tangentially.

21. A method according to claim 1, further comprising:

maintaining the temperature of the plasma between 5,000 and 15,000 degrees C.

22. A method according to claim 1, further comprising:

producing a volatile reaction on the surface of the workpiece.

23. A method according to claim 1, wherein:

the step of using reactive atom plasma processing occurs at about atmospheric pressure.

26. A method according to claim 1, further comprising:

using a precursor to control the etch rate of the plasma, the precursor being any one of a solid, liquid, or gas.

27. A method for planarizing a surface of a workpiece, comprising:

translating at least one of a workpiece and a plasma torch;

depositing material on the surface of the workpiece using the plasma torch;

removing material from the surface of the workpiece using a discharge from the plasma torch; and

using reactive atom plasma processing to redeposit the removed material on the surface of the workpiece.

29. A method according to claim 27, further comprising:

introducing reactive species into the plasma through a central channel in the plasma torch.

30. A method according to claim 27, further comprising:

placing a precursor in a central channel of the plasma.

31. A method according to claim 27, further comprising:

controlling the mass flow of a precursor into the processing chamber.

32. A method according to claim 27, further comprising:

selecting a concentration of precursor to be introduced into a central channel of the plasma.

33. A method according to claim 27, further comprising:

introducing a plasma gas through an outer tube of the plasma torch.

34. A method according to claim 27, further comprising:

coupling energy to the discharge in an annular region of the plasma torch.

35. A method according to claim 27, further comprising:

introducing an auxiliary gas through a second of three concentric tubes in the plasma torch.

38. A method according to claim 27, further comprising:

maintaining the temperature of the plasma.

39. A method according to claim 27, wherein:

the depositing and removing steps occur at atmospheric pressure.

40. A method according to claim 27, further comprising:

altering the chemistry of the surface of the workpiece with the plasma.

42. A method according to claim 27, further comprising:

controlling the removal rate at which material is removed from the surface of the workpiece.

43. A method according to claim 27, further comprising:

controlling the deposition rate at which material is deposited onto the surface of the workpiece.

44. A method according to claim 27, further comprising:

controlling the redeposition rate at which material removed from the surface during processing is redeposited on the surface.

45. A method for cleaning a surface, comprising:

translating at least one of a workpiece and a plasma torch; and

using reactive atom plasma processing to deposit and remove material from the surface of the workpiece.

46. A method for redistributing a material on a surface, comprising:

translating at least one of a workpiece and a plasma torch; and

using reactive atom plasma processing to deposit and redistribute material on the surface of the workpiece.

47. A tool for shaping the surface of a workpiece, the tool being able to accomplish the following steps:

translating at least one of the workpiece and the plasma torch; and

using reactive atom plasma processing to deposit material on the surface of the workpiece and modify the surface with the discharge from the plasma torch.

48. A tool for shaping the surface of a workpiece, comprising:

means for translating at least one of a workpiece and a plasma torch; and

means for using reactive atom plasma processing to deposit material on the surface of the workpiece and modify the surface with the discharge from the plasma torch.

49. A tool for shaping the surface of a workpiece, comprising:

a plasma torch;

a translator that can translate at least one of a workpiece and said torch; and

wherein said torch is configured to deposit material and modify the surface of a workpiece using a reactive plasma process.