Maskless lithography systems and methods utilizing spatial light modulator arrays

• US 7,403,266 B2
• Filed: 01/13/2006
• Issued: 07/22/2008
• Est. Priority Date: 05/29/2003
• Status: Expired due to Fees

• Current Assignee: ASML Holding NV
• Original Assignee: ASML Holding NV
• Inventors: Wasserman, Solomon S., McCullough, Andrew W., Van Der Mast, Karel Diederick, Hintersteiner, Jason Douglas, Cebuhar, Wenceslao A., Bleeker, Arno
• Primary Examiner(s): NGUYEN, HUNG
• Application Number:
  US11/331,064
• Publication Number:
  US 20060114438A1
• Time in Patent Office: 921 Days
• Field of Search: 355/53, 355 67- 71, 430/5, 430/20, 430/30, 359/237, 359/224, 359/291, 359/2
• US Class Current: 355/67
• CPC Class Codes: G03F 7/70283 Mask effects on the imaging process
• 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
• CPC Class Codes: G03F 7/70358 Scanning exposure, i.e. relative movement of patterned beam and workpiece during imaging
• CPC Class Codes: G03F 7/70466 Multiple exposures, e.g. combination of fine and coarse exposures, double patterning or multiple exposures for printing a single feature stitching G03F7/70475
• CPC Class Codes: G03F 7/70558 Dose control, i.e. achievement of a desired dose

Abstract

A maskless lithography system that writes patterns on an object. The system can include an illumination system, the object, spatial light modulators (SLMs), and a controller. The SLMs can pattern light from the illumination system before the object receives the light. The SLMs can include a leading set and a trailing set of the SLMs. The SLMs in the leading and trailing sets change based on a scanning direction of the object. The controller can transmit control signals to the SLMs based on at least one of light pulse period information, physical layout information about the SLMs, and scanning speed of the object. The system can also correct for dose non-uniformity using various methods.

Claims

1. A maskless lithography system, comprising:

an illumination system;

an object;

a thermally controllable support structure;

analog spatial light modulators (SLMs) that pattern light from the illumination system before the light is received by the object, wherein each SLM has a plurality of elements that are positioned to produce a plurality of gray levels to be received at the object, the SLMs being supported by the thermally controllable support structure, and wherein each one of the SLMs comprises an active area section and an inactive packaging section, and

a controller that transmits control signals to the SLMs to position the elements.

2. The system of claim 1, wherein the object is a semiconductor wafer.

3. The system of claim 1, wherein the object is a glass substrate.

4. The system of claim 3, wherein the glass substrate is part of a liquid crystal display.

5. The system of claim 1, further comprising:

a beam splitter that directs light from the light source to the SLMs and from the SLMs to the object, wherein the SLMs are reflective SLMs.

6. The system of claim 1, wherein the SLMs are transmissive SLMs.

7. The system of claim 1, wherein the SLMs are liquid crystal displays.

8. The system of claim 1, further comprising:

a beam splitter that directs light from the light source to the SLMs and from the SLMs to the object, wherein the SLMs are digital micromirror devices (DMDs).

9. The system of claim 1, wherein the control signal to the SLMs allows for more than one at least partial exposure of a same area of the object during a single scan.

10. The system of claim 1, wherein the SLMs are positioned a predetermined distance apart such that more than one SLM exposes an exposure area on the object for pulses occurring during continuous movement of the object based on the control signal.

11. The system of claim 1, wherein the SLMs are configured in a two-dimensional array.

12. The system of claim 1, wherein a first edge of a first one of the SLMs lies in a same plane as a second edge of an adjacent, second one of the SLMs.

13. The system of claim 1, wherein the SLMs are staggered with respect to adjacent SLMs.

14. The system of claim 1, wherein a set of the SLMs that writes to a same exposure area on the object includes four columns of the SLMs.

15. The system of claim 14, wherein the columns are positioned one-half of an active area apart.

16. The system of claim 14, wherein each of the SLMs has an active inactive area and wherein a top of the active area of one of the SLMs is aligned with a bottom of the active area of an adjacent one of the SLMs.

17. The system of claim 14, wherein each of the columns includes two of the SLMs.

18. The system of claim 14, wherein each of the columns includes four of the SLMs.

19. The system of claim 14, wherein the exposure area on the object moves a distance approximately equal to two active areas of the SLMs during each pulse of the illumination system.

20. The system of claim 1, wherein a set of the SLMs that writes to a same exposure area on the object includes six columns of the SLMs.

21. The system of claim 20, wherein a top of an active area of one of the SLMs is aligned with a bottom of an adjacent active area of another one of the SLMs.

22. The system of claim 20, wherein each of the columns includes four of the SLMs.

23. The system of claim 20, wherein the columns are positioned one-half of an active area apart.

24. The system of claim 20, wherein the columns are positioned one active area apart.

25. The system of claim 1, wherein a set of the SLMs that writes to a same exposure area on the object includes two columns of the SLMs.

26. The system of claim 25, wherein a top of an active area of one of the SLMs is aligned with a bottom of an adjacent active area of another of the SLMs.

27. The system of claim 25, wherein each of the columns includes four of the SLMs.

28. The system of claim 25, wherein the columns are positioned one-half of an active area apart.

29. The system of claim 25, wherein the exposure area on the object moves a distance approximately equal to one active area of the SLMs during each pulse of the illumination system.

30. The system of claim 1, wherein the SLMs are coupled to the thermally controllable support device in a two dimensional array.

31. The system of claim 30, wherein the thermally controllable support device comprises cooling channels running therethrough.

32. The system of claim 30, wherein the thermally controllable support device comprises a controller.

33. The system of claim 1, wherein the package section comprises:

a controller to control devices in the active area.

34. The system of claim 33, wherein the control circuitry controller receives the control signal from the controller.

35. The system of claim 1, wherein a set of the SLMs that writes to a same exposure area on the object includes six columns of the SLMs.

36. The system of claim 1, wherein a set of the SLMs that writes to a same exposure area on the object includes eight columns of the SLMs.