Method and system for generating a light-sustained plasma in a flanged transmission element

Patent metadata

Field	Value
Publication number	US-9775226-B1
Application number	US-201414231196-A
Country	US
Kind code	B1
Filing date	Mar 31, 2014
Priority date	Mar 29, 2013
Publication date	Sep 26, 2017
Grant date	Sep 26, 2017

Abstract

A system for forming a light-sustained plasma capable of emitting vacuum ultraviolet light includes an illumination source configured to generate illumination, a plasma cell including a transmission element having one or more openings, one or more flanges disposed at the openings of the transmission element and configured to enclose the internal volume of the transmission element in order to contain a volume of gas within the plasma cell. The system further includes a collector element arranged to focus the illumination from the illumination source into the volume of gas to generate a plasma within the volume of gas contained within the plasma cell. Further, the plasma emits broadband radiation including at least vacuum ultraviolet radiation. In addition, the transmission element of the plasma cell is transparent to the illumination generated by the illumination source and at least the vacuum ultraviolet radiation emitted by the plasma.

First claim

What is claimed:

1. A system for forming a light-sustained plasma comprising:
an illumination source configured to generate illumination;
a plasma cell including a transmission element having a first opening and a second opening;
a first removable flange and a second removable flange attachable to the first opening and the second opening of the transmission element and configured to enclose the internal volume of the transmission element in order to contain a volume of gas within the plasma cell;
one or more fins external to the transmission element and coupled to the first flange and the second flange, the one or more fins configured to secure the first flange over the first opening and the second flange over the second opening, wherein the one or more fins transfer thermal energy from a portion of the plasma cell to an ambient atmosphere;
one or more internal control elements mechanically coupled to an internal surface of at least one of the one or more removable flanges, the one or more internal control elements including one or more protruding portions, the one or more protruding portions protruding into the volume of the transmission element beyond the internal surface of the at least one of the one or more removable flanges upon attachment of the one or more removable flanges to the one or more openings of the transmission element, wherein the one or more internal control elements are removable from the internal volume of the transmission element upon removal of the one or more removable flanges, wherein the one or more internal control elements include at least one of a temperature control device, a convection control device, a plume control device, a gas fill device or an ignition device; and
a collector element arranged to focus the illumination from the illumination source into the volume of gas in order to generate a plasma within the volume of gas contained within the plasma cell,
wherein the plasma emits broadband radiation including at least vacuum ultraviolet radiation,
wherein the transmission element of the plasma cell is at least partially transparent to at least a portion of the illumination generated by the illumination source and at least a portion of the broadband radiation emitted by the plasma.

2. The system of claim 1 , wherein the first opening and the second opening of the transmission element comprise:
a first opening at a first end of the transmission element; and
a second opening at a second end of the transmission element opposite the first end.

3. The system of claim 1 , wherein the transmission element has at least one of a substantially cylindrical shape and a substantially spherical shape.

4. The system of claim 1 , wherein the transmission element has a composite shape.

5. The system of claim 1 , wherein the temperature control device comprises:
at least one of an active temperature control device or a passive temperature control device.

6. The system of claim 1 , wherein the convection control device comprises:
one or more flow control structures.

7. The system of claim 1 , wherein the plume control device comprises:
a plume control device including a concave portion for at least one of capture or redirection of a plasma plume.

8. The system of claim 1 , wherein the gas fill control device comprises:
at least one of a pipe or a tube.

9. The system of claim 1 , wherein the ignition device comprises:
one or more electrodes.

10. The system of claim 1 , further comprising:
one or more radiation shielding elements.

11. The system of claim 10 , wherein the one or more radiation shielding elements comprise:
a radiation shield proximate to the one or more openings of the transmission element configured to block radiation from at least one of the illumination source and the radiation generated by the plasma from reaching one or more seals of the plasma cell.

12. The system of claim 1 , further comprising:
a coating layer proximate to the one or more openings of the transmission element configured to block at least a portion of the radiation generated by the plasma from reaching one or more seals of the plasma cell.

13. The system of claim 1 , wherein the transmission element of the plasma cell is at least partially transparent to radiation between 120 nm and 200 nm.

14. The system of claim 1 , wherein the transmission element of the plasma cell is formed from at least one of calcium fluoride, magnesium fluoride, crystalline quartz, sapphire, and fused silica.

15. The system of claim 1 , wherein broadband radiation emitted by the plasma further includes at least one of deep ultraviolet radiation, ultraviolet radiation, and visible radiation.

16. The system of claim 15 , wherein the transmission element of the plasma cell is at least partially transparent to at least one of vacuum ultraviolet radiation, deep ultraviolet radiation, ultraviolet radiation, and visible radiation emitted by the plasma.

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

18. The system of claim 1 , wherein the collector element comprises:
an ellipsoid-shaped collector element.

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

20. The system of claim 19 , wherein the one or more lasers comprise:
one or more infrared lasers.

21. The system of claim 19 , wherein the one or more lasers comprise:
at least one of a diode laser, a continuous wave laser, or a broadband laser.

22. The system of claim 1 , wherein the gas comprises:
one or more inert gases.

23. The system of claim 1 , wherein the gas comprises:
one or more non-inert gases.

24. The system of claim 1 , wherein the gas comprises:
a mixture of two or more gases.

25. A system for forming a light-sustained plasma comprising:
an illumination source configured to generate illumination;
a plasma cell including a transmission element having one or more openings;
one or more removable flanges attachable to the one or more openings of the transmission element and configured to enclose the internal volume of the transmission element in order to contain a volume of gas within the plasma cell;
one or more fins external to the transmission element and coupled to the first flange and the second flange, the one or more fins configured to secure the first flange over the first opening and the second flange over the second opening, wherein the one or more fins transfer thermal energy from a portion of the plasma cell to an ambient atmosphere;
one or more control elements mechanically coupled to a surface of at least one of the one or more removable flanges, wherein the one or more control elements include at least one of a temperature control device, a convection control device, a plume control device, a gas fill device, or an ignition device; and
a collector element arranged to focus the illumination from the illumination source into the volume of gas in order to generate a plasma within the volume of gas contained within the plasma cell,
wherein the plasma emits broadband radiation,
wherein the transmission element of the plasma cell is at least partially transparent to at least a portion of the illumination generated by the illumination source and at least a portion of the broadband radiation emi

Assignees

• Kla Tencor Corp

Inventors

• Bezel Ilya
• Shchemelinin Anatoly
• Derstine Matthew

Classifications

• 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

• H01J61/52 Primary

  Cooling arrangements; Heating arrangements; Means for circulating gas or vapour within the discharge space {(heating or cooling arrangements to promote ionisation for starting H01J61/54)} · CPC title

• H05H1/24 Primary

  Generating plasma {(nuclear fusion reactors G21B1/00; gas-filled discharge reactors H01J37/32)} · CPC title