Radiation source and a method for use in metrology applications

Patent metadata

Field	Value
Publication number	US-11467339-B2
Application number	US-202117190474-A
Country	US
Kind code	B2
Filing date	Mar 3, 2021
Priority date	Jul 19, 2019
Publication date	Oct 11, 2022
Grant date	Oct 11, 2022

Abstract

A system and method for providing a radiation source. In one arrangement, the radiation source includes an optical fiber that is hollow, and has an axial direction, a gas that fills the hollow of the optical fiber, and a plurality of temperature setting devices disposed at respective positions along the axial direction of the optical fiber, wherein the temperature setting devices are configured to control the temperature of the gas to locally control the density of the gas.

First claim

The invention claimed is:

1. A radiation source, comprising:
an optical fiber that is hollow, and has an axial direction; and
one or more temperature setting devices,
wherein the one or more temperature devices are configured to control a temperature of a gas so as to control the density of gas that fills the hollow of the optical fiber.

2. The radiation source of claim 1 , wherein the optical fiber is located in a first chamber and the one or more temperature setting devices are configured to control the temperature of gas in a second chamber, the second chamber fluidly connected to the first chamber.

3. The radiation source of claim 2 , wherein the first chamber is thermally insulated from the second chamber.

4. The radiation source of claim 1 , further comprising:
a sensor configured to measure flow through an orifice fluidly connecting the first and second chambers; and
a controller configured to control, based on an output of the sensor, the one or more temperature setting devices.

5. The radiation source of claim 1 , further comprising:
a sensor configured to take a property measurement of the output of the radiation source; and
a controller configured to control, based on an output of the sensor, the one or more temperature setting devices.

6. The radiation source of claim 1 , further comprising:
a temperature sensor configured to take a temperature measurement of the gas controlled by the one or more temperature devices; and
a controller configured to control, based on an output of the sensor, the one or more temperature setting devices.

7. The radiation source of claim 1 , wherein the gas comprises a noble gas.

8. A metrology device, comprising:
a stage configured to hold a substrate, and
the radiation source of claim 1 for projecting radiation onto the stage.

9. A radiation source, comprising:
an optical fiber that is hollow, and has an axial direction, the optical fiber located in a first chamber; and
one or more temperature setting devices, the one or more temperature setting devices configured to change a pressure of gas in a second chamber,
wherein the change of pressure is communicated to the first chamber via a fluid connection between the first and second chambers.

10. The radiation source of claim 9 , wherein the first chamber is thermally insulated from the second chamber.

11. The radiation source of claim 9 , further comprising:
a sensor configured to take a property measurement of the output of the radiation source; and
a controller configured to control, based on an output of the sensor, the one or more temperature setting devices.

12. The radiation source of claim 9 , further comprising:
a temperature sensor configured to take a temperature measurement of the gas in the second chamber; and
a controller configured to control, based on an output of the sensor, the one or more temperature setting devices.

13. The radiation source of claim 9 , further comprising:
a sensor configured to measure flow through an orifice fluidly connecting the first and second chambers; and
a controller configured to control, based on an output of the sensor, the one or more temperature setting devices.

14. The radiation source of claim 9 , wherein the gas comprises a noble gas.

15. A metrology device, comprising:
a stage configured to hold a substrate, and
the radiation source of claim 9 for projecting radiation onto the stage.

16. A radiation source, comprising:
an optical fiber that is hollow, and has an axial direction; and
one or more temperature setting devices configured to change a pressure of gas,
wherein the change of pressure is applied to gas that fills the hollow of the optical fiber.

17. The radiation source of claim 16 , wherein the optical fiber is located in a first chamber and the one or more temperature setting devices are configured to control the temperature of gas in a second chamber, the second chamber fluidly connected to the first chamber.

18. The radiation source of claim 17 , wherein the first chamber is thermally insulated from the second chamber.

19. The radiation source of claim 16 , further comprising:
a sensor configured to take a property measurement of the output of the radiation source; and
a controller configured to control, based on an output of the sensor, the one or more temperature setting devices.

20. A metrology device, comprising:
a stage configured to hold a substrate, and
the radiation source of claim 16 for projecting radiation onto the stage.

Assignees

• Asml Netherlands Bv

Inventors

• Sabert Hendrik
• Uebel Patrick Sebastian

Classifications

• G03F7/70025

  by lasers · CPC title

• G03F7/70008

  Production of exposure light, i.e. light sources · CPC title

• G02F1/383

  of the optical fibre type · CPC title

• G02B6/0239

  Comprising means for varying the guiding properties, e.g. tuning means · CPC title

• G03F7/70616

  Monitoring the printed patterns · CPC title