Vacuum system for immersion photolithography

Patent metadata

Field	Value
Publication number	US-10168624-B2
Application number	US-201715857368-A
Country	US
Kind code	B2
Filing date	Dec 28, 2017
Priority date	Jun 16, 2004
Publication date	Jan 1, 2019
Grant date	Jan 1, 2019

Abstract

A vacuum system for extracting a stream of a multi-phase fluid from a photolithography tool comprises a pumping arrangement for drawing the fluid from the tool, and an extraction tank located upstream from the pumping arrangement for separating the fluid drawn from the tool into gas and liquid phases. The pumping arrangement comprises a first pump for extracting gas from the tank, and a second pump for extracting liquid from the tank. In order to minimize any pressure fluctuations transmitted from the vacuum system back to the fluid within the tool, a pressure control system maintains a substantially constant pressure in the tank by regulating the amounts of liquid and gas within the tank.

First claim

The invention claimed is:

1. An extraction system configured to extract a multi-phase fluid from a part of a lithography tool, the extraction system comprising:
a separator to separate the multi-phase fluid drawn from the part of the lithography tool into a gas phase and a liquid phase;
a pump device to draw the multi-phase fluid from the part of the lithography tool, the pump device comprising:
a first pump unit configured to extract gas from the separator, and
a second pump unit configured to extract liquid from the separator; and
a pressure control system configured to control a pressure within the separator by regulating an amount of gas and an amount of liquid therein, the pressure control system comprising:
a gas opening configured to allow supply of gas to the separator;
a liquid opening configured to allow supply of liquid to the separator; and
a control system configured to control a flow rate of gas to the separator and control a flow rate of liquid to the separator.

2. The extraction system of claim 1 , further comprising a variable flow control device through which gas is supplied to the separator via the gas opening and the control system is configured to vary a conductance of the variable flow control device to control the pressure within the separator.

3. The extraction system of claim 1 , wherein the control system is configured to receive a signal indicative of the pressure within the separator and to control the flow rate of gas to the separator based on the received signal.

4. The extraction system of claim 1 , wherein the control system is arranged to control a level of liquid within the separator.

5. The extraction system of claim 1 , wherein the separator comprises an extraction tank.

6. An apparatus comprising:
a lithography tool; and
the extraction system according to claim 1 .

7. An apparatus, comprising:
a nozzle configured to remove a mixture of liquid and gas; and
an extraction system configured to draw the mixture through the nozzle, the extraction system comprising:
a separator configured to separate each of liquid and gas from the removed mixture;
a gas opening configured to allow gas to the separator from a source thereof;
a liquid opening configured to allow liquid to the separator from a source thereof; and
a control system configured to control a flow rate of gas to the separator and to control a flow rate of liquid to the separator.

8. The apparatus of claim 7 , wherein the extraction system is arranged to maintain a substantially stable pressure within the separator.

9. The apparatus of claim 7 , wherein the control system is arranged to control a level of liquid within the separator.

10. The apparatus of claim 7 , wherein the control system is configured to control a pressure within the separator by regulating the gas and/or liquid therein.

11. A lithographic apparatus, comprising:
a projection device configured to project a radiation beam onto a substrate;
an inlet configured to provide a liquid to a space between the projection device and the substrate;
an outlet configured to remove at least part of the liquid as a multi-phase fluid;
a separator configured to receive the multi-phase fluid from the outlet, the separator configured to separate the fluid into gas and liquid phases;
a first opening configured to exhaust separated gas from the separator; and
a second opening configured to exhaust separated liquid from the separator, the first opening being located at a different height than the second opening.

12. The apparatus of claim 11 , further comprising a pump arrangement configured to draw the multi-phase fluid into the separator.

13. The apparatus of claim 11 , further comprising a pump arrangement configured to extract separated liquid, via the second opening, from the separator.

14. The apparatus of claim 11 , further comprising a control system configured to control a pressure within the separator by regulating the gas and/or liquid therein.

15. The apparatus of claim 11 , further comprising a control system configured to control flow of gas from the separator.

16. The apparatus of claim 11 , further comprising a control system configured to control an amount of liquid within the separator.

17. The apparatus of claim 11 , further comprising a flow restriction in a fluid path from the separator to a pump fluidly connected to the separator.

18. The apparatus of claim 11 , wherein the separator comprises a chamber having the first and second openings therein.

19. The apparatus of claim 11 , wherein the first opening is higher than the second opening.

20. The apparatus of claim 11 , further comprising a control system configured to control a level of liquid within the separator.

Assignees

• Asml Netherlands Bv

Inventors

• Harpham Andrew John
• Shechter Paul John
• Stockman Paul Alan

Classifications

• G03F7/70858 Primary

  Environment aspects, e.g. pressure of beam-path gas, temperature (pollution aspects G03F7/70916) · CPC title

• G03F7/70341 Primary

  Details of immersion lithography aspects, e.g. exposure media or control of immersion liquid supply (chemical composition of immersion liquids G03F7/2041) · CPC title

• G03F7/70841

  Constructional issues related to vacuum environment, e.g. load-lock chamber · CPC title

• B01D57/00

  Separation, other than separation of solids, not fully covered by a single other group or subclass, e.g. B03C · CPC title

• G03F7/20 Primary

  Exposure; Apparatus therefor (photographic printing apparatus for making copies G03B27/00) · CPC title