Lithographic apparatus and in-line cleaning apparatus

Patent metadata

Field	Value
Publication number	US-9405205-B2
Application number	US-201514714944-A
Country	US
Kind code	B2
Filing date	May 18, 2015
Priority date	Dec 20, 2007
Publication date	Aug 2, 2016
Grant date	Aug 2, 2016

Abstract

A lithographic system includes an immersion type lithographic apparatus, which includes a support constructed and arranged to support a substrate, a projection system constructed and arranged to project a patterned beam of radiation onto a target portion of the substrate, a liquid confinement structure configured to at least partially fill a space between the projection system and at least one of the substrate and support with an immersion liquid, a liquid supply system arranged to provide the immersion liquid to the liquid confinement structure, and a cleaning liquid supply system arranged to provide a cleaning liquid to a surface of the lithographic apparatus that comes into contact with the immersion liquid. The system includes a switch to provide the cleaning liquid directly to the liquid confinement structure and to provide the immersion liquid indirectly to the liquid confinement structure via a liquid purification system.

First claim

What is claimed is:

1. An immersion type lithographic system, comprising:
an immersion type lithographic apparatus, comprising:
a support constructed and arranged to support a substrate,
a projection system constructed and arranged to project a patterned beam of radiation onto a target portion of the substrate, and

a liquid confinement structure configured to at least partially fill a space between the projection system and the substrate and/or support with an immersion liquid;
a liquid supply system constructed and arranged to supply the immersion liquid to the liquid confinement structure; and
a cleaning system constructed and arranged to supply a cleaning liquid comprising a cleaner to a part of the liquid confinement structure to clean the part of the liquid confinement structure, the cleaning system further comprising an outlet system configured and arranged to receive a used cleaning liquid and the cleaning system further configured to select a cleaning mode from a plurality of cleaning modes and provide the cleaner from a plurality of different cleaners to the part of the liquid confinement structure based on the selected cleaning mode.

2. The immersion type lithographic system according to claim 1 , wherein the liquid confinement structure is configured such that the cleaning liquid passes through the liquid confinement structure.

3. The immersion type lithographic system according to claim 1 , wherein the part is a bottom surface of the liquid confinement structure.

4. The immersion type lithographic system according to claim 1 , wherein the part is a micro sieve provided in the bottom surface.

5. The immersion type lithographic system according to claim 1 , wherein the cleaning system is constructed and arranged to supply ultra-pure water to the part of the liquid confinement structure to rinse the part of the liquid confinement structure after cleaning the part of the liquid confinement structure.

6. The immersion type lithographic system according to claim 1 , wherein the outlet system comprises a separator configured to separate liquid and gas phases included in the used cleaning liquid.

7. The immersion type lithographic system according to claim 6 , wherein the outlet system comprises a degasser to remove the gas from the cleaning liquid, the outlet system further comprising a drain configured to receive a liquid exiting the degasser.

8. The immersion type lithographic system according to claim 7 , further comprising a recycle system and a drain switch to direct the liquid exiting the degasser to the recycle system or to a waste drain for removal.

9. The immersion type lithographic system according to claim 8 , wherein the recycle system is configured to purify the liquid for reuse as immersion liquid by the liquid supply system.

10. The immersion type lithographic system according to claim 1 , wherein the lithographic apparatus further comprises an indicator configured to indicate whether the part of the lithographic apparatus should be cleaned.

11. The immersion type lithographic system according to claim 10 , wherein the indicator comprises at least one selected from the group consisting of: i) an exposure counter configured to count a number of substrates exposed since a previous cleaning action; ii) a timer configured to time the duration since a previous cleaning action; iii) a particle counter configured to count a number of contaminant particles that have exited the immersion system over a certain amount of time; and iv) a sensor configured to sense a certain level of contamination in the lithographic apparatus.

12. The immersion type lithographic system according to claim 1 , wherein the cleaner comprises an alkali fluid.

13. The immersion type lithographic system according to claim 1 , the cleaning system being in fluid communication with the liquid supply system and the liquid confinement structure.

14. A method of cleaning an immersion type lithographic apparatus, the method comprising:
receiving an indication that a part of a liquid confinement structure of the immersion type lithographic apparatus should be cleaned;
selecting a cleaning mode from among a plurality of different cleaning modes based on the indication;
providing a cleaning liquid comprising a cleaner selected based on the cleaning mode, from a cleaning system to the part of the liquid confinement structure of the immersion type lithographic apparatus to clean the part of the liquid confinement structure; and
providing a rinsing liquid to the part of the immersion type lithographic apparatus to rinse the part.

15. The method according to claim 14 , wherein the rinsing liquid comprises ultra-pure water.

16. The method according to claim 14 , wherein the cleaner comprises at least one selected from the group consisting of: ozone, an alkaline, a soap, and an acid.

17. The method according to claim 14 , wherein the cleaning system is located in an in-line cleaning cabinet, the in-line cleaning cabinet being in fluid communication with the immersion type lithographic apparatus.

18. The method according to claim 14 , further comprising providing a used cleaning liquid, the used cleaning liquid being the cleaning liquid provided to clean the part, to an outlet system.

19. The method according to claim 18 , further comprising removing ozone from the used cleaning liquid using a degasser of the outlet system.

20. The method according to claim 19 , further comprising directing a liquid exiting the degasser to a recycle system for reuse in the lithographic apparatus or to a waste drain for removal.

21. An immersion type lithographic system, comprising:
a support constructed and arranged to support a substrate;
a projection system constructed and arranged to project a patterned beam of radiation onto a target portion of the substrate; and
a liquid confinement structure configured to at least partially fill a space between the projection system and the substrate and/or support with an immersion liquid;
a liquid supply system constructed and arranged to supply the immersion liquid to the liquid confinement structure;
an indicator configured to provide a signal to indicate whether a part of the lithographic apparatus should be cleaned; and
a cleaning system constructed and arranged to supply a cleaning liquid comprising a cleaner to a part of the liquid confinement structure to clean the part of the liquid confinement structure, the cleaning system further constructed and arranged to select among a plurality of different cleaning modes using the cleaning liquid based on the signal.

22. The immersion type lithographic system according to claim 21 , wherein the cleaning system is constructed and arranged to provide the cleaner from a plurality of different cleaners to the part of the liquid confinement structure based on the selected cleaning mode.

Assignees

• Asml Netherlands Bv

Inventors

• De Graaf Roelof Frederik
• Jansen Hans
• Jansen Bauke
• Heusschen Hubertus Leonardus Franciscus

Classifications

• G03F7/7085

  Detection arrangement, e.g. detectors of apparatus alignment possibly mounted on wafers, exposure dose, photo-cleaning flux, stray light, thermal load · CPC title

• G03F7/70341

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

• G03F7/70925 Primary

  Cleaning, i.e. actively freeing apparatus from pollutants, e.g. using plasma cleaning · CPC title