Systems and methods for protecting an EUV light source chamber from high pressure source material leaks

1. A device comprising:

a chamber;

a fluid line;

a pressurized source material in said fluid line;

a component restricting flow of said source material into said chamber;

a sensor measuring flow of a fluid in said fluid line and providing a signal indicative thereof, wherein said fluid pressurizes said source material in said fluid line; and

a pressure relief valve responsive to said signal to change a pressure that said fluid in said fluid line exerts upon said source material to reduce a leak of source material into said chamber in the event of a failure of said component.

2. A device as recited in claim 1 wherein said component is a droplet nozzle.

3. A device as recited in claim 2 wherein said droplet nozzle comprises a glass capillary tube.

4. A device as recited in claim 1 wherein said fluid is a gas.

5. A device as recited in claim 1 further comprising a laser system for irradiating said source material in said chamber to create an EUV light emitting plasma.

6. A device as recited in claim 1 further comprising an electro-actuable element coupled to said component for generating a stream of droplets from said source material.

7. A device as recited in claim 1 further comprising a control circuit processing said signal from said sensor and providing a control signal to said pressure relief valve.

8. A device as recited in claim 1 wherein said pressure relief valve directs fluid from said fluid line to a second fluid line and said device further comprises a vacuum pump connected to said second fluid line.

9. A device as recited in claim 8 comprises a valve operable on said second fluid line to direct flow between a first portion of said second fluid line outputting flow to a surrounding atmosphere and a second portion of aid second fluid line, said second portion connected to a vacuum pump.

10. A device comprising:

a chamber;

a fluid line;

means for pressurizing, using a fluid different from said a source material, said source material in said fluid line;

means for restricting flow of said source material into said chamber; and

means for reducing pressure of said fluid in said fluid line to change a pressure that said fluid in said fluid line exerts upon said source material to reduce a leak of source material into said chamber in the event of a failure of said restricting means.

11. A device as recited in claim 10 wherein said means for restricting is a droplet nozzle having a glass capillary tube.

12. A device as recited in claim 10 wherein said fluid is a gas.

13. A device as recited in claim 10 further comprising a laser system for irradiating said source material in said chamber to create an EUV light emitting plasma.

14. A device as recited in claim 10 wherein said pressure reducing means comprises a means for measuring a pressure of said fluid in said fluid line and producing a signal indicative thereof, a means for processing said signal and providing a control signal, and a valve actuable by said control signal.

15. A device as recited in claim 10 wherein said pressure reducing means comprises a means for measuring a flow of said fluid in said fluid line and producing a signal indicative thereof, a means for processing said signal and providing a control signal, and a valve actuable by said control signal.

16. A method comprising the acts of:

providing a chamber and a fluid line;

pressurizing a fluid in said fluid line to cause said fluid to pressurize a source material in said fluid line;

using a component to restrict flow of said source material into said chamber;

measuring flow of said fluid in said fluid line and providing a signal indicative thereof; and

reducing pressure in said fluid line in response to a signal to change a pressure that said fluid in said fluid line exerts upon said source material to reduce a leak of source material into said chamber in the event of a failure of said component.

17. A method as recited in claim 16 wherein said component is a glass capillary tube.

18. A method as recited in claim 16 wherein said fluid is a gas.

19. A method as recited in claim 16 further comprising the step of:

irradiating said source material with a laser beam in said chamber to create an EUV light emitting plasma.

20. A method as recited in claim 16 further comprising diverting said fluid to a low pressure environment that is created by a vacuum pump to reduce said pressure that said fluid in said fluid line exerts upon said source material.