System and method for inhibiting radiative emission of a laser-sustained plasma source

Patent metadata

Field	Value
Publication number	US-9615439-B2
Application number	US-201614989348-A
Country	US
Kind code	B2
Filing date	Jan 6, 2016
Priority date	Jan 9, 2015
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

A system for forming a laser-sustained plasma includes a gas containment element, an illumination source configured to generate pump illumination, and a collector element. The gas containment element is configured to contain a volume of a gas mixture. The collector element is configured to focus the pump illumination from the pumping source into the volume of the gas mixture contained within the gas containment element in order to generate a plasma within the volume of the gas mixture that emits broadband radiation. The gas mixture filters one or more selected wavelengths of radiation emitted by the plasma.

First claim

What is claimed is:

1. A system for forming a laser-sustained plasma, comprising:
a gas containment element, wherein the gas containment element is configured to contain a volume of a gas mixture;
an illumination source configured to generate pump illumination; and
a collector element configured to focus the pump illumination from the pumping source into the volume of the gas mixture contained within the gas containment element in order to generate a plasma within the volume of the gas mixture, wherein the plasma emits broadband radiation, wherein the gas mixture inhibits the emission of one or more selected wavelengths of radiation from the gas containment element.

2. The system of claim 1 , wherein the gas containment element includes at least one of a chamber, a plasma bulb or a plasma cell.

3. The system of claim 1 , wherein the broadband radiation including one or more selected wavelengths emitted by the plasma includes in at least one of infrared wavelengths, visible wavelengths, UV wavelengths, DUV wavelengths, VUV wavelengths, or EUV wavelengths.

4. The system of claim 1 , wherein the one or more selected wavelengths of radiation inhibited by the gas mixture include wavelengths lower than 600 nm.

5. The system of claim 1 , wherein the gas mixture absorbs the one or more selected wavelengths of radiation emitted by the plasma.

6. The system of claim 1 , wherein the gas mixture comprises:
at least two of the group including argon, mercury, xenon, krypton, radon, neon and at least one metal halide compound.

7. The system of claim 1 , wherein the gas mixture comprises:
at least one of argon or neon having a first partial pressure of at least 10 atmospheres; and
an additional gas component including at least one of xenon, krypton, or radon, the additional gas component having a second partial pressure of less than 20% of the first partial pressure.

8. The system of claim 1 , wherein the gas mixture includes one or more gas components to quench radiative emission of excimers in the gas mixture.

9. The system of claim 8 , wherein the one or more gas components substantially quench radiative emission of excimers in the gas mixture by at least one of collisional dissociation, a photolytic process, or resonance excitation transfer.

10. The system of claim 8 , wherein the one or more gas components include at least one of O 2 , N 2 , CO 2 , H 2 O, SF 6 , I 2 , Br 2 or Hg.

11. The system of claim 8 , wherein the gas mixture includes xenon and at least one of O 2 or N 2 .

12. The system of claim 8 , wherein the gas mixture includes neon and H 2 .

13. The system of claim 8 , wherein the gas mixture includes argon and at least one of xenon or N 2 .

14. The system of claim 1 , wherein the collector element is arranged to collect at least a portion of the broadband radiation emitted by the plasma and direct the broadband radiation to one or more additional optical elements.

15. The system of claim 1 , wherein the gas mixture inhibits radiation including wavelengths within an absorption spectrum of one or more propagation elements.

16. The system of claim 15 , wherein the one or more propagation elements comprise:
at least one of the collector element, a transmission element, a reflective element, or a focusing element.

17. The system of claim 15 , wherein the one or more propagation elements are formed from at least one of crystalline quartz, sapphire, fused silica, calcium fluoride, lithium fluoride, or magnesium fluoride.

18. The system of claim 1 , wherein inhibiting radiation by the gas mixture inhibits damage to one or more components of the system.

19. The system of claim 18 , wherein the damage includes solarization.

20. The system of claim 1 , wherein the gas mixture inhibits radiation including wavelengths within an absorption spectrum of one or more additional elements.

21. The system of claim 20 , wherein the one or more additional elements comprise:
at least one of a flange or a seal.

22. The system of claim 1 , wherein the illumination source comprises:
one or more lasers.

23. The system of claim 22 , wherein the one or more lasers comprise:
one or more infrared lasers.

24. The system of claim 22 , wherein the one or more lasers comprise:
at least one of a diode laser, a continuous wave laser, or a broadband laser.

25. The system of claim 1 , wherein the illumination source comprises:
an illumination source configured to emit pump illumination at a first wavelength and illumination at an additional wavelength different from the first wavelength.

26. The system of claim 1 , wherein the illumination source comprises:
an adjustable illumination source, wherein a wavelength of the pump illumination emitted by the illumination source is adjustable.

27. The system of claim 1 , wherein the collector element is positioned external to the gas containment element.

28. The system of claim 1 , wherein the collector element is positioned internal to the gas containment element.

29. The system of claim 1 , wherein the collector element comprises:
at least one of an ellipsoid-shaped collector element or a spherical-shaped collector element.

30. A plasma lamp for forming a laser-sustained plasma, comprising:
a gas containment element, wherein the gas containment element is configured to contain a volume of a gas mixture, wherein the gas mixture is further configured to receive pump illumination in order to generate a plasma within the volume of the gas mixture, wherein the plasma emits broadband radiation, wherein the gas mixture inhibits the emission of one or more selected wavelengths of radiation from the gas containment element.

31. A method for generating laser-sustained plasma radiation, comprising:
generating pump illumination;
containing a volume of a gas mixture within a gas containment structure;
focusing at least a portion of the pump illumination to one or more focal spots within the volume of the gas mixture to sustain a plasma within the volume of the gas mixture, wherein the plasma emits broadband radiation; and
inhibiting the emission of one or more selected wavelengths of radiation from the gas containment structure via the gas mixture.

Assignees

• Kla Tencor Corp

Inventors

• Bezel Ilya
• Shchemelinin Anatoly
• Gross Kenneth P
• Solarz Richard
• Wilson Lauren
• Yadav Rahul
• Wittenberg Joshua
• Chimmalgi Anant
• Liu Xiumei
• Bruguier Brooke

Classifications

• H01J61/16 Primary

  having helium, argon, neon, krypton, or xenon as the principle constituent · CPC title

• H01J65/00

  Lamps without any electrode inside the vessel; Lamps with at least one main electrode outside the vessel · CPC title

• H01J61/025

  Associated optical elements · CPC title

• H01J65/04 Primary

  Lamps in which a gas filling is excited to luminesce by an external electromagnetic field or by external corpuscular radiation, e.g. for indicating {plasma display panels} · CPC title

• H05G2/003

  the plasma being generated from a material in a liquid or gas state · CPC title