System and method for imaging enhancement via calculation of a customized optimal pupil field and illumination mode

• US 7,542,013 B2
• Filed: 01/31/2005
• Issued: 06/02/2009
• Est. Priority Date: 01/31/2005
• Status: Expired due to Fees

• Current Assignee: ASML Holding NV
• Original Assignee: ASML Holding NV
• Inventors: Latypov, Azat M., Cebuhar, Wenceslao A., Hintersteiner, Jason D.
• Primary Examiner(s): LEWIS, DAVID LEE
• Application Number:
  US11/046,236
• Publication Number:
  US 20060170617A1
• Time in Patent Office: 1,583 Days
• Field of Search: 345/108, 345/109, 345/687, 345/4, 345/32, 345/204, 349/4, 359/292, 359/293
• US Class Current: 345/32
• CPC Class Codes: G03F 7/70116 Off-axis setting using a programmable means, e.g. liquid crystal display [LCD], digital micromirror device [DMD] or pupil facets

Abstract

A system and method for patterning a beam of radiation based on a pupil field distribution. In an embodiment, the distribution of the field in an area of the pupil plane affecting an image and an illumination mode are selected so as to render an image with desired characteristics. Additionally and/or alternatively, an illumination mode is selected so as to render an image with desired characteristics. The distribution of the field in an area of the pupil plane affecting an image is then realized using the spatial light modulator The system and method include using an illumination system, a pattern generator, and a projector. The illumination system supplies a beam of radiation. The pattern generator patterns the beam of radiation based on a data set corresponding to a field distribution in a pupil plane. The projector projects the patterned beam onto a target portion of an object.

Claims

1. A method, comprising:

receiving a data set based on a field distribution in a pupil plane of a projection system, the field distribution corresponding to an image;

modifying the data set to result in a modified data set that represents a desired field distribution in the pupil plane of the projection system, the desired field distribution corresponding to the image having desired characteristics;

setting states of pixels located on a dynamic pattern generator according to the modified data set;

patterning a beam of radiation with the dynamic pattern generator; and

projecting the patterned beam onto a target portion of a substrate.

2. The method of claim 1, wherein modifying the data set comprises selecting an illumination mode of an extended source optically conjugate to the field distribution in the pupil plane, such that the modification of the data set in results in the desired field distribution in the pupil plane.

3. The method of claim 2, wherein modifying the data set further comprises using at least one of a conventional, an annular, a quasar, a dipole, a quadrapole, a hexapole, an octapole, a polarized, an unpolarized, an on-axis, and an off-axis mode as the illumination mode.

4. The method of claim 1, wherein modifying the data set comprises using at least one of placement of features, image log slope, critical dimension uniformity, contrast of image, and out-of-focus behavior as the desired characteristics of the image.

5. The method of claim 1, wherein receiving the data set comprises:

calculating an inverse Fourier Transform of an image field corresponding to a desired image in the image plane; and

using the calculation of the inverse Fourier Transform as the data set.

6. The method of claim 1, wherein modifying the data set comprises:

computing, from the data set received based on the field distribution in the pupil plane, the image that corresponds to the field distribution in the pupil plane;

determining if there are discrepancies between characteristics of the image and the desired characteristics; and

iteratively modifying the data set to minimize the discrepancies, thereby resulting in the modified data set.

7. The method of claim 1, wherein modifying the data set comprises modifying the data set so that the modified data set accounts for at least one of optical proximity effects and optical proximity correction features in the pupil field distribution.

8. The method of claim 1, wherein patterning the beam of radiation comprises using at least one of tilting reflective devices, pistoning reflective devices, graytoning transmissive devices, and graytoning reflective devices in the dynamic pattern generator.

9. The method of claim 1, wherein projecting the patterned beam comprises using at least one of a wafer, a projection system display devices, and a projection television display device as the substrate.

10. The method of claim 1, further comprising using at least one of an aerial image and an image in a layer of photoresist disposed on the substrate as the image.

11. The method of claim 1, wherein receiving the data set comprises using imaging characteristics of at least one of a binary mask pattern, attenuated phase-shift mask pattern, an alternating phase-shift mask pattern, and a multi-phase mask pattern as a basis for the data set.

12. The method of claim 1, wherein receiving the data set comprises using the desired characteristics at the substrate as a basis for the data set.

13. A system for patterning a beam of radiation, comprising:

an illumination system configured to supply the beam of radiation;

an image controller configured to receive a data set based on a field distribution in a pupil plane of a projection system and modify the data set to result in a modified data set that represents a desired field distribution in the pupil plane of the projection system, the desired field distribution corresponding to an image having desired characteristics; and

a pattern generator configured to pattern the beam of radiation based on the modified data set; and

a projector configured to project the patterned beam onto a target portion of a substrate.

14. The system of claim 13, wherein the image controller is configured to transform the modified data set into states of pixels located on a dynamic pattern generator.

15. The system of claim 14, wherein:

the image controller is configured to determine an illumination mode of an extended source optically conjugate to the pupil plane, such that the data set results in the desired field distribution in the pupil plane.

16. The system of claim 15, wherein the illumination mode comprises at least one of a conventional, an annular, a quasar, a dipole, a quadrapole, a hexapole, an octapole, a polarized, an unpolarized, an on-axis, and an off-axis mode.

17. The system of claim 13, wherein the desired field distribution corresponds with an image at an image plane having at least one of placement of features, image log slope, critical dimension uniformity, image contrast, and out-of-focus behavior.

18. The system of claim 13, wherein the data set comprises an inverse Fourier Transform of an image.

19. The system of claim 13, wherein the pattern generator comprises at least one of tilting reflective devices, pistoning reflective devices, graytoning transmissive devices, and graytoning reflective devices.

20. The system of claim 13, wherein the substrate comprises at least one of a wafer, a projection system display device, and a projection television system display device.