System and method to compensate for critical dimension non-uniformity in a lithography system

• US 20080024744A1
• Filed: 07/27/2006
• Published: 01/31/2008
• Est. Priority Date: 07/27/2006
• Status: Active Grant

• Current Assignee: ASML Netherlands BV (ASML Holding NV)
• Original Assignee: ASML Netherlands BV (ASML Holding NV)
• Inventors: Van Horssen, Hermanus Gerardus
• Granted Patent: US 7,548,315 B2
• Time in Patent Office: Days
• US Class Current: 355/53
• CPC Class Codes: G03F 7/70441 Optical proximity correction [OPC]
• CPC Class Codes: G03F 7/70566 Polarisation control

Abstract

A system and method are used to compensate for critical dimension non-uniformity caused by different polarization directions in an illumination beam. A system comprises a source of radiation and an optical system. The source of radiation produces a beam of radiation. The optical system is configured to transmit a first portion of the beam having a first polarization direction during a first portion of a cycle and a second portion of the beam having a second polarization direction during a second portion of the cycle.

Claims

1. A system, comprising:

a source of radiation that produces a beam of radiation; and

an optical system configured to transmit a first portion of the beam having a first polarization direction during a first portion of a cycle and a second portion of the beam having a second polarization direction during a second portion of the cycle.

2. The system of claim 1, wherein the optical system comprises:

a polarizer; and

an actuator that rotates the polarizer 90 degrees between the first portion and the second portion of the cycle.

3. The system of claim 1, wherein the optical system comprises:

a polarizing beam splitter; and

an actuator that rotates the polarizing beam splitter 90 degrees between the first portion and the second portion of the cycle.

4. The system of claim 1, further comprising:

a patterning device configured to pattern the first portion of the beam during the first portion of the cycle and the second portion of the beam during the second portion of the cycle; and

a projection system that projects the first and second patterned beams onto a target portion of a substrate.

5. The system of claim 4, further comprising:

an illumination system configured to process the first portion of the beam during the first portion of the cycle and the second portion of the beam during the second portion of the cycle and to direct the first and second processed beams onto the patterning device.

6. The system of claim 5, wherein the illumination system comprises the radiation source and the optical system.

7. The system of claim 5, wherein the source of radiation, the patterning device, or the illumination system is adjusted during the first and second portions of the cycle to correspond to the polarization direction.

8. The system of claim 4, wherein the patterning device is configured to change a pattern on the patterning device in accordance with whether the first or second portion of the beam is being patterned.

9. The system of claim 4, wherein the system is configured to establish the first portion of the cycle as a first exposure pass in a first scanning direction and the second portion of the cycle as a second exposure pass in a second, opposite scanning direction.

10. A lithography system, comprising:

an illumination system that generates an illumination beam of radiation, comprising,

a source of radiation that produces a beam of radiation; and

an optical system configured to transmit a first portion of the illumination beam having a first polarization direction during a first portion of a cycle and a second portion of the illumination beam having a second polarization direction during a second portion of the cycle;

a patterning device that patterns the first and second portions of the illumination beam of radiation; and

a projection system that projects the first and second patterned beams onto a target portion of a substrate.

11. The lithography system of claim 10, wherein the optical system comprises:

a polarizer; and

an actuator that rotates the polarizer 90 degrees between the first portion and the second portion of the cycle.

12. The lithography system of claim 10, wherein the optical system comprises:

a polarizing beam splitter; and

an actuator that rotates the polarizing beam splitter 90 degrees between the first portion and the second portion of the cycle.

13. The lithography system of claim 10, wherein the patterning device is configured to change a pattern on the patterning device in accordance with whether the first or second portion of the illumination beam is being patterned.

14. The lithography system of claim 10, wherein the lithography system is configured to establish the first portion of the cycle as a first exposure pass in a first scanning direction and the second portion of the cycle as a second exposure pass in a second, opposite scanning direction.

15. The lithography system of claim 10, wherein the source of radiation, the patterning device, or the illumination system is adjusted during the first and second portions of the cycle to correspond to the polarization direction.

16. A laser that outputs first and second polarization directions of radiation, comprising:

a source of radiation that produces a beam of radiation; and

an optical system configured to transmit a first portion of the beam having a first polarization direction during a first portion of a cycle and a second portion of the beam having a second polarization direction during a second portion of the cycle.

17. The laser of claim 16, wherein the optical system comprises:

a polarizer; and

an actuator that rotates the polarizer 90 degrees between the first portion and the second portion of the cycle.

18. The laser of claim 16, wherein the optical system comprises:

a polarizing beam splitter; and

an actuator that rotates the polarizing beam splitter 90 degrees between the first portion and the second portion of the cycle.

19. An illuminator that outputs first and second polarization directions of radiation, comprising:

a source of radiation that produces a beam of radiation; and

an optical system configured to transmit a first portion of the beam having a first polarization direction during a first portion of a cycle and a second portion of the beam having a second polarization direction during a second portion of the cycle.

20. The illuminator of claim 19, wherein the optical system comprises:

a polarizer; and

an actuator that rotates the polarizer 90 degrees between the first portion and the second portion of the cycle.

21. The illuminator of claim 19, wherein the optical system comprises:

a polarizing beam splitter; and

an actuator that rotates the polarizing beam splitter 90 degrees between the first portion and the second portion of the cycle.

22. A method, comprising:

(a) producing a beam of radiation during an exposure cycle;

(b) directing a first portion of the beam having a first polarization direction onto a dynamic patterning device during a first portion of the exposure cycle;

(c) projecting the patterned beam onto a target portion of a substrate;

(d) directing a second portion of the beam having a second polarization direction onto the dynamic patterning device during a second portion of the exposure cycle; and

(e) projecting the patterned beam onto the target portion of the substrate.

23. Forming a integrated circuit on a wafer using the method of claim 22.

24. Forming a flat panel device on a flat panel glass substrate using the method of claim 22.

25. The method of claim 22, further comprising adjusting a pattern formed on the dynamic patterning device to correlate with whether the first portion or the second portion of the beam is being patterned.