Method for inductively-driven plasma light source

• US 8,143,790 B2
• Filed: 10/31/2007
• Issued: 03/27/2012
• Est. Priority Date: 07/09/2004
• Status: Active Grant

• Current Assignee: Hamamatsu Photonics KK
• Original Assignee: Energetiq Technology Incorporated (Hamamatsu Photonics KK)
• Inventors: Smith, Donald K., Horne, Stephen F., Besen, Matthew M., Blackborow, Paul A.
• Primary Examiner(s): TRAN, THUY V
• Application Number:
  US11/930,856
• Publication Number:
  US 20080042591A1
• Time in Patent Office: 1,609 Days
• Field of Search: 315/56, 315/57, 315/70, 315/248, 315/111.01, 315/111.11, 315/111.21, 315/111.41, 315/111.51, 315/111.71
• US Class Current: 315/111.11
• CPC Class Codes: H01J 65/048 the field being produced by using an excitation coil
• CPC Class Codes: H05G 2/003 being produced from a liquid or gas

Abstract

A method for producing light includes introducing an ionizable medium for generating a plasma into a chamber. The method also includes applying at least one pulse of energy to a magnetic core that surrounds a portion of a plasma discharge region within the chamber such that the magnetic core delivers power to the plasma which forms a secondary of a transformer according to Faraday'"'"'s law of induction. The plasma has a localized high intensity zone.

Claims

1. A method for generating a light signal comprising:

introducing an ionizable medium into a chamber;

ionizing the ionizable medium to form a plasma,

applying at least one pulse of energy to a magnetic core that surrounds a portion of a plasma discharge region within the chamber such that the magnetic core delivers power to the plasma which forms a secondary of a transformer according to Faraday'"'"'s law of induction;

confining the plasma in the plasma discharge region to form a Z-pinch, wherein the Z-pinch is a localized high intensity plasma zone; and

providing a coolant to transfer heat away from a portion of the chamber adjacent to the localized high intensity plasma zone.

2. The method of claim 1 wherein the plasma current density along a path of current flow in the plasma is greater than 1 KA/cm² in the Z-pinch.

3. The method of claim 1 wherein the plasma zone is a point source of high intensity light.

4. The method of claim 1 wherein the Z-pinch forms a neck.

5. The method of claim 1 comprising defining a necked region for localizing an emission of light by the plasma.

6. The method of claim 1 wherein the pulse power system comprises an energy storage device.

7. The method of claim 6 wherein the energy storage device comprises at least one capacitor.

8. The method of claim 1 wherein the pulse power system comprises a second magnetic core.

9. The method of claim 8 comprising discharging each pulse of energy from the second magnetic core to the first magnetic core to deliver power to the plasma.

10. The method of claim 8 wherein ionizing the ionizable medium comprises pre-ionizing the ionizable medium using inductive leakage current flowing from the second magnetic core to the magnetic core surrounding the portion of the plasma discharge region.

11. The method of claim 1 comprising compressing each pulse of energy prior to applying the pulse of energy to the magnetic core.

12. The method of claim 1 wherein the Z-pinch is produced in a channel region located in the chamber.

13. The method of claim 1 wherein the Z-pinch forms a capillary discharge in a channel region located in the chamber.

14. The method of claim 1 comprising introducing the ionizable medium into the chamber via at least one port.

15. The method of claim 1 comprising providing an ionizable medium comprising at least one or more gases selected from the group consisting of Xenon, Lithium, Tin, Nitrogen, Argon, Helium, Fluorine, Ammonia, Stannane, Krypton and Neon.

16. The method of claim 1 wherein ionizing the ionizable medium comprises pre-ionizing the ionizable medium with an ionization source.

17. The method of claim 1 comprising forming a primary winding around the core with two parallel plates of an enclosure.

18. The method of claim 1 comprising producing light at wavelengths shorter than about 100 nm.

19. The method of claim 18 comprising producing light at wavelengths shorter than about 15 nm.

20. The method of claim 1 wherein providing the coolant to transfer heat away from the portion of the chamber involves pressurized subcooled flow boiling of water.