Generation of uniformly-distributed plasma

DC CAFC

US 6,903,511 B2
Filed: 05/06/2003
Issued: 06/07/2005
Est. Priority Date: 05/06/2003
Status: Expired due to Term

- Alert
- Pin

Associated Cases

Associated Defendants

First Claim

Patent Images

1. A plasma generator comprising:

a. a cathode assembly that is positioned adjacent to an anode and forming a gap there between;

b. a gas source that supplies a volume of feed gas;

c. an excited atom source that generates a volume of excited atoms from the volume of feed gas supplied by the gas source, the excited atom source supplying the volume of excited atoms to the gap; and

d. a power supply that generates an electric field across the gap between the cathode assembly and the anode, the electric field ionizing the volume of gas excited atoms that is supplied to the gap by the excited atom source, thereby creating a plasma in the gap.

View all claims

1 Assignment

Timeline View

Assignment View

Litigations

0 Petitions

Accused Products

Abstract

Methods and apparatus for generating uniformly-distributed plasma are described. A plasma generator according to the invention includes a cathode assembly that is positioned adjacent to an anode and forming a gap there between. A gas source supplies a volume of feed gas and/or a volume of excited atoms to the gap between the cathode assembly and the anode. A power supply generates an electric field across the gap between the cathode assembly and the anode. The electric field ionizes the volume of feed gas and/or the volume of excited atoms that is supplied to the gap, thereby creating a plasma in the gap.

280 Citations

50 Claims

1. A plasma generator comprising:
- a. a cathode assembly that is positioned adjacent to an anode and forming a gap there between;
  
  b. a gas source that supplies a volume of feed gas;
  
  c. an excited atom source that generates a volume of excited atoms from the volume of feed gas supplied by the gas source, the excited atom source supplying the volume of excited atoms to the gap; and
  
  d. a power supply that generates an electric field across the gap between the cathode assembly and the anode, the electric field ionizing the volume of gas excited atoms that is supplied to the gap by the excited atom source, thereby creating a plasma in the gap.
- View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
- - 2. The plasma generator of claim 1 wherein the cathode assembly comprises a target.
  - 3. The plasma generator of claim 1 further comprising a gas flow controller that controls the volume of feed gas supplied by the gas source.
  - 4. The plasma generator of claim 1 wherein the power supply is chosen from the group comprising a pulsed DC power supply, a RF power supply, an AC power supply, and a DC power supply.
  - 5. The plasma generator of claim 1 wherein the power supply generates a constant power.
  - 6. The plasma generator of claim 1 wherein the power supply generates a constant voltage.
  - 7. The plasma generator of claim 1 wherein a width of the gap is in the range of about 0.3 cm to 10 cm.
  - 8. The plasma generator of claim 1 further comprising a magnet assembly that generates a magnet field that substantially traps electrons in the plasma.
  - 9. The plasma generator of claim 1 wherein a peak plasma density of the plasma is in the range of about 10⁷cm⁻
    - 3 to 10¹⁶cm^−
      
      3.
  - 10. The plasma generator of claim 1 wherein the cathode assembly comprises a hollow cathode comprising an inner surface that substantially surrounds the anode.
  - 11. The plasma generator of claim 10 wherein the inner surface comprises a cylindrical wall.
  - 12. The plasma generator of claim 1 wherein the plasma created in the gap diffuses proximate to a surface of the cathode assembly.
  - 13. The plasma generator of claim 12 wherein the plasma is substantially uniformly-distributed proximate to the surface of the cathode assembly.
  - 14. The plasma generator of claim 12 wherein at least one of a width of the gap and a flow rate of the volume of feed gas that is supplied by the gas source is chosen to increase a density of the plasma proximate to the surface of the cathode assembly.
  - 15. The plasma generator of claim 12 wherein at least one of a width of the gap and a flow rate of the volume of feed gas that is supplied by the gas source is chosen to increase uniformity of the plasma proximate to the surface of the cathode assembly.
  - 16. The plasma generator of claim 12 wherein a pressure in the gap is higher than a pressure proximate to the surface of the cathode assembly.

17. A plasma generator comprising:
- a. a cathode assembly that is positioned adjacent to an anode and forming a gap there between;
  
  b. an excited atom source that generates a volume of excited atoms from a volume of feed gas, the excited atom source supplying the volume of excited atoms to the gap between the cathode assembly and the anode; and
  
  c. a power supply that generates an electric field across the gap between the cathode assembly and the anode, the electric field ionizing the volume of excited atoms that is supplied to the gap, thereby creating a plasma in the gap.
- View Dependent Claims (18, 19, 20, 21, 22, 23, 24, 25, 26, 27)
- - 18. The plasma generator of claim 17 wherein at least a portion of the volume of excited atoms comprises metastable atoms.
  - 19. The plasma generator of claim 17 further comprising a gas flow controller that controls the volume of excited atoms supplied to the gap.
  - 20. The plasma generator of claim 17 wherein a width of the gap is in the range of about 0.3 cm to 10 cm.
  - 21. The plasma generator of claim 17 further comprising a magnet assembly that generates a magnet field that substantially traps electrons in the plasma.
  - 22. The plasma generator of claim 17 wherein the cathode assembly comprises a hollow cathode comprising an inner surface that substantially surrounds the anode.
  - 23. The plasma generator of claim 22 wherein the inner surface comprises a cylindrical wall.
  - 24. The plasma generator of claim 17 wherein the plasma created in the gap diffuses proximate to a surface of the cathode assembly.
  - 25. The plasma generator of claim 24 wherein the plasma is substantially uniformly-distributed proximate to the surface of the cathode assembly.
  - 26. The plasma generator of claim 24 wherein at least one of a width of the gap and a flow rate of the volume of excited atoms that is supplied to the gap is chosen to increase a density of the plasma proximate to the surface of the cathode assembly.
  - 27. The plasma generator of claim 24 wherein at least one of a width of the gap and a flow rate of the volume of excited atoms that is supplied to the gap is chosen to increase uniformity of the plasma proximate to the surface of the cathode assembly.

28. A method for generating a plasma, the method comprising:
- a. supplying a volume of feed gas;
  
  b. generating a volume of excited atoms from the volume of feed gas and supplying the volume of excited atoms to a gap between a cathode assembly and an anode; and
  
  c. applying an electric field across the gap, the electric field ionizing the volume of feed gas that is supplied to the gap, thereby creating a plasma in the gap.
- View Dependent Claims (29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43)
- - 29. The method of claim 28 further comprising adjusting a flow rate of the volume of feed gas supplied so as to increase a density of the plasma.
  - 30. The method of claim 28 further comprising supplying a second volume of excited atoms that is generated from a second volume of feed gas, the second volume of excited atoms displacing the plasma.
  - 31. The method of claim 28 wherein the applying the electric field across the gap comprises applying a quasi-static electric field across the gap.
  - 32. The method of claim 28 wherein the applying the electric field across the gap comprises applying the electric field at a constant power.
  - 33. The method of claim 28 wherein the applying the electric field across the gap comprises applying the electric field at a constant voltage.
  - 34. The method of claim 28 wherein a peak plasma density of the plasma is in the range of about 10⁷cm⁻
    - 3 to 10¹⁶cm ^−
      
      3.
  - 35. The method of claim 28 further comprising generating a magnetic field proximate to the plasma, the magnetic field trapping electrons in the plasma, thereby increasing the density of the plasma.
  - 36. The method of claim 35 wherein the magnetic field generated proximate to the plasma in the gap and the electric field applied across the gap intersect in the gap.
  - 37. The method of claim 28 wherein the applying the electric field across the gap comprises applying a pulsed electric field across the gap.
  - 38. The method of claim 37 further comprising selecting characteristics of the pulsed electric field to increase an ionization rate of the plasma.
  - 39. The method of claim 37 wherein a rise time of the pulsed electric field is in the range of about 0.1 microsecond to 10 seconds.
  - 40. The method of claim 28 wherein the plasma created in the gap diffuses proximate to a surface of the cathode assembly.
  - 41. The method of claim 40 further comprising adjusting the flow rate of the volume of feed gas supplied so as to increase uniformity of the plasma proximate to the surface of the cathode assembly.
  - 42. The method of claim 40 further comprising selecting a width of the gap to increase a density of the plasma proximate to the surface of the cathode assembly.
  - 43. The method of claim 40 further comprising selecting a width of the gap to increase uniformity of the plasma proximate to the surface of the cathode assembly.

44. A method for generating a plasma, the method comprising:
- a. generating a volume of excited atoms from a volume of feed gas;
  
  b. supplying the volume of excited atoms to a gap between a cathode assembly and an anode; and
  
  c. applying an electric field across the gap, the electric field ionizing the volume of excited atoms that is supplied to the gap, thereby creating a plasma in the gap.
- View Dependent Claims (45, 46, 47, 48, 49)
- - 45. The method of claim 44 wherein at least a portion of the volume of excited atoms comprises metastable atoms.
  - 46. The method of claim 44 further comprising supplying a second volume of excited atoms to the gap, the second volume of excited atoms displacing the plasma.
  - 47. The method of claim 44 wherein the plasma created in the gap diffuses proximate to a surface of the cathode assembly.
  - 48. The method of claim 47 further comprising adjusting a flow rate of the volume of excited atoms to increase a density of the plasma proximate to the surface of the cathode assembly.
  - 49. The method of claim 47 further comprising adjusting the flow rate of the volume of excited atoms to increase uniformity of the plasma proximate to the surface of the cathode assembly.

50. A plasma generator comprising:
- a. means for generating a volume of excited atoms from a volume of feed gas;
  
  b. means for supplying the volume of excited atoms to a gap between a cathode assembly and an anode; and
  
  c. means for applying an electric field across the gap, the electric field ionizing the volume of excited atoms that is supplied to the gap, thereby creating a plasma in the gap.

Specification

Resources

Litigation Campaign Assessment

Litigation Data

Current Assignee
ZOND Incorporated
Original Assignee
ZOND Incorporated
Inventors
Chistyakov, Roman
Primary Examiner(s)
Vo, Tuyet Thi

Application Number

US10/249,774
Publication Number

US 20040222745A1
Time in Patent Office

763 Days
Field of Search

315/111.71, 315/111.91, 315/111.81, 315/111.41, 315/111.21, 204/192, 204/298
US Class Current

315/111.71
CPC Class Codes

C23C 14/34   Sputtering

C23C 14/35   by application of a magneti...

H01J 37/3244   Gas supply means

H01J 37/3405   Magnetron sputtering

Generation of uniformly-distributed plasma

First Claim

1 Assignment

Litigations

0 Petitions

Accused Products

Abstract

280 Citations

50 Claims

Specification

Solutions

Use Cases

Quick Links

Generation of uniformly-distributed plasma

First Claim

1 Assignment

Subscription Required

Subscription Required

Litigations

0 Petitions

Subscription Required

Accused Products

Subscription Required

Abstract

280 Citations

50 Claims

Specification

Subscription Required

Solutions

Use Cases

Quick Links