Method and system for maskless lithography real-time pattern rasterization and using computationally coupled mirrors to achieve optimum feature representation

• US 7,773,287 B2
• Filed: 04/24/2007
• Issued: 08/10/2010
• Est. Priority Date: 06/30/2005
• Status: Active Grant

• Current Assignee: ASML Holding NV
• Original Assignee: ASML Holding NV
• Inventors: Troost, Kars Zegar, Baselmans, Johannes Jacobus Matheus, Latypov, Azat M.
• Primary Examiner(s): Thompson; Timothy J
• Assistant Examiner(s): Tra; Tuyen Q
• Application Number:
  US11/790,222
• Publication Number:
  US 20070268547A1
• Time in Patent Office: 1,204 Days
• Field of Search: 359/292, 359/237, 359/223, 359/318, 359/281, 359/285, 359/578, 359/855, 355/53, 355/67, 355/71, 355/77
• US Class Current: 359/292
• CPC Class Codes: G03F 7/70291 Addressable masks, e.g. spatial light modulators [SLMs], digital micro-mirror devices [DMDs] or liquid crystal display [LCD] patterning devices

Abstract

A method and system for determining specific pixel modulation states of a spatial light modulator (SLM) to print a desired pattern on a substrate are disclosed. The method includes selecting at least one super-pixel in an object plane of the desired pattern, the super-pixel being formed of at least two pixels. At least one edge of the desired pattern crosses a boundary within the super-pixel, the at least one edge being defined by specific slope and position parameters relative to the super-pixel. The method also includes (i) forming an interpolation table to tabulate pre-calculated pixel modulation states and (ii) determining the specific pixel modulation states for each of the pixels in accordance with the interpolation table. Disclosed also are a method and system for providing a spatial light modulator (SLM). The SLM includes a plurality of mirrors structured to form groups of super-pixels. Each super-pixel (i) includes two or more mirrors from the plurality of mirrors and (ii) is configured to switch only one pixel of light. Each of the two or more mirrors can be separately actuated.

Claims

1. A spatial light modulator (SLM), comprising:

a plurality of mirrors structured to form groups of super-pixels, each super-pixel including two or more mirrors from the plurality of mirrors;

wherein, for a given super-pixel, individual mirrors of the two or more mirrors of that given super-pixel are configured to be separately actuated to compensate for an imperfection of at least one of the two or more mirrors of that given super-pixel.

2. The spatial light modulator of claim 1, wherein the plurality of mirrors is configured to perform pure gray modulation.

3. The spatial light modulator of claim 1, wherein the plurality of mirrors are pistoning mirrors.

4. The spatial light modulator of claim 1, wherein the two or more mirrors within each super-pixel cooperate to behave as a single tilting mirror.

5. The spatial light modulator of claim 1, wherein the two or more mirrors includes at least four mirrors.

6. The spatial light modulator of claim 1, wherein the two or more mirrors form an array.

7. The spatial light modulator of claim 6, wherein each mirror within the array represents a degree of manipulation freedom.

8. The spatial light modulator of claim 1, wherein the actuation of each mirror is caused by a separate piston.

9. The spatial light modulator of claim 1, wherein each of the two or more mirrors can be individually addressed.

10. A method for modulating light within a spatial light modulator (SLM) including a plurality of mirrors, the method comprising:

configuring groups of mirrors within the plurality of mirrors to form super-pixels, each super-pixel including two or more mirrors from the plurality of mirrors;

individually addressing each of the two or more mirrors within the super-pixel such that the SLM performs at least one of pure gray-level modulation and pure phase modulation; and

re-configuring particular mirrors within at least one group of the groups of mirrors to compensate for defects in at least one other mirror within the at least one group.

11. The method of claim 10 wherein the re-configuring is based upon at least one of a measured actuation level and an image intensity associated with the particular mirrors.

12. An apparatus for modulating light within a spatial light modulator (SLM) including a plurality of mirrors, the apparatus comprising:

means for configuring groups of mirrors within the plurality of mirrors to form super-pixels, each super-pixel including two or more mirrors from the plurality of mirrors; and

means for individually addressing each of the two or more mirrors within the super-pixel such that the SLM performs at least one of pure gray-level modulation and pure phase modulation;

wherein, for a given super-pixel, individual mirrors of the two or more mirrors of that given super-pixel are configured to be separately actuated to compensate for an imperfection of at least one of the two or more mirrors of that given super-pixel.

13. An apparatus for modulating light within a spatial light modulator (SLM) including a plurality of mirrors, the apparatus comprising:

means for configuring groups of mirrors within the plurality of mirrors to form super-pixels, each super-pixel including two or more mirrors from the plurality of mirrors; and

means for individually addressing each of the two or mirrors within the super-pixel such that the SLM performs at least one of pure gray-level modulation and pure phase modulation;

wherein imperfections of individual mirrors of the two or more mirrors are compensated for by separately actuating the two or more mirrors to cause the two or more mirrors to act as a single pixel.

14. A method for modulating light within a spatial light modulator (SLM) including a plurality of mirrors, the method comprising:

configuring groups of mirrors within the plurality of mirrors to form super-pixels, each super-pixel including two or more mirrors from the plurality of mirrors;

individually addressing each of the two or more mirrors within the super-pixel such that the SLM performs at least one of pure gray-level modulation and pure phase modulation; and

compensating for parasitic tilt errors of an assembly of n×

m pixels of light from the super-pixel by collectively actuating n×

m mirrors of the super-pixel using n×

n degrees of freedom.

15. A method for modulating light within a spatial light modulator (SLM) including a plurality of mirrors, the method comprising:

configuring groups of mirrors within the plurality of mirrors to form super-pixels, each super-pixel including two or more mirrors from the plurality of mirrors;

individually addressing each of the two or more mirrors within the super-pixel such that the SLM performs at least one of pure gray-level modulation and pure phase modulation; and

computationally coupling individual mirrors of the SLM for rasterizing the plurality of mirrors of the SLM by configuring the SLM in super-pixels to project a desired maskless lithography real-time pattern onto a substrate with an optimum feature representation.