Claims
- 1. A magnetically enhanced plasma chamber comprising:
a cathode pedestal for supporting a wafer within an enclosure; a plurality of electromagnets, located proximate the enclosure, for producing a magnetic field within the enclosure; and a magnetic field control element positioned proximate the plurality of electromagnets, for altering the magnetic field generated by the plurality of electromagnets near a selected region of the wafer.
- 2. The chamber of claim 1 wherein said magnetic field control element comprises:
a plurality of counter coils, where one counter coil is positioned proximate to each of the electromagnets in said plurality of electromagnets and the counter coils produce a magnetic field that has an opposite direction to the direction of the magnetic field produced by the electromagnets.
- 3. The chamber of claim 2 wherein each of the electromagnets is associated with a counter coil, the electromagnets and counter coils are annular, the electromagnets have a diameter that is larger than the diameter of the counter coils where each electromagnet has one counter coil positioned within each of the electromagnets.
- 4. The chamber of claim 3 wherein the counter coils and the electromagnets have ears that are bent inward toward the enclosure.
- 5. The chamber of claim 3 wherein the electromagnets are planar and the counter coils have ears that are bent inward toward the enclosure.
- 6. The chamber of claim 2 wherein the counter coils produce a magnetic field at a center of the wafer having a magnitude that is less than a magnitude of a magnetic field at the center of the wafer produced by said electromagnets.
- 7. The chamber of claim 1 wherein the magnetic field control element comprises:
a shunt ring fabricated of magnetic material and position proximate the wafer.
- 8. The chamber of claim 7 wherein the shunt ring has a square cross-section.
- 9. The chamber of claim 7 wherein the shunt ring has a width that is greater than a height.
- 10. The chamber of claim 7 where the magnetic material is steel or nickel.
- 11. The chamber of claim 7 wherein the shunt ring is positioned coplanar with the wafer.
- 12. The chamber of claim 7 further comprising a second shunt ring positioned coaxial with the shunt ring, where the shunt ring has a diameter that is smaller than a diameter of the second shunt ring.
- 13. The chamber of claim 7 wherein the shunt ring is encapsulated within an edge ring.
- 14. The chamber of claim 1 wherein the electromagnets are annular defining an opening and the magnetic field control element comprises a magnetic shield positioned within the opening of each of the electromagnets.
- 15. The chamber of claim 14 wherein the magnetic shield comprises a substantially rectangular block of magnetic material.
- 16. The chamber of claim 14 wherein the magnetic shield comprises four bars arranged in a rectangle.
- 17. The chamber of claim 14 wherein the magnetic shield comprises a pair of bars.
- 18. The chamber of claim 14 wherein the pair of bars are oriented horizontally or vertically.
- 19. The chamber of claim 1 wherein the means comprises a plurality of corner shields positioned at a location where two electromagnets are nearest each other.
- 20. The chamber of claim 19 wherein the corner shields are fabricated of a magnetic material.
- 21. The chamber of claim 19 wherein the corner shields comprise elongate members having a first portion and a second portion connected to form an angle.
- 22. The magnetically enhanced plasma chamber of claim 1 wherein the magnetic field control element comprises:
a plurality of center shields positioned between the plurality of electromagnets and the cathode pedestal.
- 23. The magnetically enhanced plasma chamber of claim 22 wherein each center shield in the plurality of center shields has a cylindrical cross-section.
- 24. The magnetically enhanced plasma chamber of claim 22 wherein each center shield in the plurality of center shields has a rectangular cross-section.
- 25. A magnetically enhanced plasma chamber comprising:
a cathode pedestal for supporting a wafer within an enclosure; a plurality of electromagnets, located proximate the enclosure, for producing a magnetic field within the enclosure; and a plurality of counter coils, positioned proximate the plurality of electromagnets, for altering the magnetic field at a specific region of the wafer, where one counter coil is positioned proximate to each of the electromagnets in said plurality of electromagnets and the counter coils produce a magnetic field that has an opposite direction to the direction of the magnetic field produced by the electromagnets.
- 26. The chamber of claim 25 wherein each of the electromagnets is associated with a counter coil, the electromagnets and counter coils are annular, the electromagnets have a diameter that is slightly larger than the diameter of the counter coils where each electromagnet has one counter coil positioned within each of the electromagnets.
- 27. The chamber of claim 26 wherein the counter coils and the electromagnets have ears that are bent inward toward the enclosure.
- 28. The chamber of claim 26 wherein the electromagnets are planar and the counter coils have ears that are bent inward toward the enclosure.
- 29. The chamber of claim 25 wherein the counter coils produce a magnetic field at a center of the wafer having a magnitude that is less than a magnitude of a magnetic field at the center of the wafer produced by the electromagnets.
- 30. A magnetically enhanced plasma chamber comprising:
a cathode pedestal for supporting a wafer within an enclosure; a plurality of electromagnets, located proximate the enclosure, for producing a magnetic field within the enclosure; and a shunt ring, fabricated of magnetic material and positioned proximate the wafer, for altering the magnetic field at a specific region of the wafer.
- 31. The chamber of claim 30 wherein the shunt ring has a square cross-section.
- 32. The chamber of claim 30 wherein the shunt ring has a width that is greater than a height.
- 33. The chamber of claim 30 where the magnetic material is steel or nickel.
- 34. The chamber of claim 30 wherein the shunt ring is positioned coplanar with the wafer.
- 35. The chamber of claim 30 further comprising a second shunt ring positioned coaxial with the shunt ring, where the shunt ring has a diameter that is smaller than a diameter of the second shunt ring.
- 36. The chamber of claim 30 wherein the shunt ring is encapsulated within a dielectric edge ring.
- 37. A magnetically enhanced plasma chamber comprising:
a cathode pedestal for supporting a wafer within an enclosure; a plurality of annular electromagnets that define an opening, located proximate the enclosure, for producing a magnetic field within the enclosure; and a magnetic shield positioned within the opening of each of the electromagnets.
- 38. The chamber of claim 37 wherein the magnetic shield comprises a substantially rectangular block of magnetic material.
- 39. The chamber of claim 37 wherein the magnetic shield comprises four bars arranged in a rectangle.
- 40. The chamber of claim 37 wherein the magnetic shield comprises a pair of bars.
- 41. The chamber of claim 37 wherein the pair of bars are oriented horizontally or vertically.
- 42. A magnetically enhanced plasma chamber comprising:
a cathode pedestal for supporting a wafer within an enclosure; a plurality of electromagnets, located proximate the enclosure, for producing a magnetic field within the enclosure; and a plurality of corner shields positioned at a location where two electromagnets are nearest each other.
- 43. The chamber of claim 42 wherein the corner shields are fabricated of a magnetic material.
- 44. The chamber of claim 42 wherein the corner shields comprise elongate members having a first portion and a second portion connected to form an angle.
- 45. A magnetically enhanced plasma chamber comprising:
a cathode pedestal for supporting a wafer within an enclosure; a plurality of electromagnets, located proximate the enclosure, for producing a magnetic field within the enclosure; and a plurality of center shields positioned between the plurality of electromagnets and the cathode pedestal.
- 46. The magnetically enhanced plasma chamber of claim 45 wherein each center shield in the plurality of center shields has a cylindrical cross-section.
- 47. The magnetically enhanced plasma chamber of claim 45 wherein each center shield in the plurality of center shields has a rectangular cross-section.
- 48. A method for providing a magnetic field gradient in a magnetically enhanced plasma reactor, comprising:
creating a plasma proximate a cathode pedestal within an enclosure; applying a magnetic field to the plasma from a plurality of electromagnets positioned proximate the enclosure; and altering the magnetic field proximate a specific region of the cathode pedestal.
Priority Claims (2)
Number |
Date |
Country |
Kind |
2001-335364 |
Oct 2001 |
JP |
|
2001-206905 |
Jul 2001 |
JP |
|
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 10/146,443, filed May 14, 2002, entitled “Method and Apparatus for Controlling the Magnetic Field Intensity in a Plasma Enhanced Semiconductor Wafer Processing Chamber”, (Attorney Docket 6348), which is herein incorporated by reference in its entirety.
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
10146443 |
May 2002 |
US |
Child |
10205870 |
Jul 2002 |
US |