Optical spot grid array printer

• US 20030123040A1
• Filed: 11/07/2002
• Published: 07/03/2003
• Est. Priority Date: 11/07/2001
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Almogy, Gilad
• Granted Patent: US 6,897,941 B2
• Time in Patent Office: Days
• US Class Current: 355/69
• CPC Class Codes: G03F 7/70275 Multiple projection paths, e.g. array of projection systems, microlens projection systems or tandem projection systems
• 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 7/70391 Addressable array sources specially adapted to produce patterns, e.g. addressable LED arrays

Abstract

A high resolution and high data rate spot grid array printer system is provided, wherein an image is formed by scanning spot-grid array of optical beams across a substrate layered with a resist. High resolution is achieved by apodizing the optical beams to provide a narrower main lobe. Unwanted recordation of side lobes upon the substrate is prevented by assuring that the side lobes do not include energy above the threshold of the resist, using a memoryless resist, and by using a slanted and interleaved scan pattern adapted for use with the spot-grid array pattern and the memoryless characteristic of the resist.

Claims

1. A printer adapted for use with a substrate layered with a memoryless resist, the printer comprising:

a programmable optical radiation source for providing an array of substantially parallel optical beams, the optical beams individually modulated in response to the input signal;

a beam shaper for narrowing the optical beams;

focusing optics positioned to receive the narrowed modulated optical beams and for focusing the narrowed modulated optical beams; and

a movable stage for introducing a linear movement between the substrate and the focused narrowed modulated optical beams, the translation providing for a slanted scan.

2. The printer of claim 1, wherein the programmable optical radiation source provides a sequence of modulated optical beam arrays, each corresponding to an intermediate pattern on the substrate, and the superposition of the intermediate patterns forms a final image on the substrate.

3. The printer of claim 1 wherein the light source comprises an array of lasers.

4. The printer of claim 1, wherein the light source is a continuous light source.

5. The printer of claim 1, wherein the light source is a pulsed light source.

6. The printer of claim 1, wherein the focusing optics comprises a microlens array, with one lens element corresponding to each individual light beam.

7. The printer of claim 6, wherein the micro-lenses are diffractive.

8. The printer of claim 1, wherein the array of light beams is two-dimensional.

9. The printer of claim 1, further comprising a demagnifier positioned between the focusing optics and the substrate for demagnifying the pattern of focused narrowed modulated optical beams.

10. The printer of claim 1, wherein as the substrate is moved a distance substantially equal to a length of the array in the scanning direction, the optical beams trace a substantially continuous path on the substrate surface in a mechanical cross-scan direction.

11. The printer of claim 10, wherein the movable stage is for moving the substrate such that the optical beams overlap by integer fractions of a pixel width as they trace the continuous path on the substrate.

12. The printer of claim 11, wherein the programmable optical radiation source periodically blanks the optical beams when the stage is for moving the substrate such that an interleaved scan pattern is formed on substrate.

13. The printer of claim 1, further comprising a detector coupled to the stage for detecting positional errors and a compensator for varying the path of the optical beams to compensate for positional errors.

14. The printer of claim 13, wherein the compensator is selected from the group consisting of a movable mirror, an electro-optic element and an acousto-optic element for varying an angle of incidence of the optical beams onto the surface of the substrate for compensating for positional errors.

15. The printer of claim 14, comprising a servo for moving the focusing optics to compensate for positional errors inaccuracies in the movement of the stage.

16. The printer of claim 9, further comprising a detector coupled to the stage for detecting positional errors and a compensator for moving the demagnifier to compensate for positional errors.

17. The printer of claim 1, adapted for use with a fluid having a substantially optimized refractive index disposed in and filling a gap between the printer and the focusing optics.

18. The printer of claim 1, wherein the beam shaper comprises a member having an array of ring apertures corresponding to the lenses of the micro-lens array.

19. The printer of claim 1, wherein the beam shaper generates a beam having a main lobe and at least one side lobe, wherein the side lobes have an amplitude and side lobes have an amplitude and a radius such that the resist is not permanently exposed by a single exposure to a side lobe.

20. The printer of claim 1, wherein the stage is for moving the substrate relative to the beam shaper such that a time period that exceeds a response period of the resist elapses between a plurality of consecutive irradiations of a single area of the substrate by the side lobes.

21. Apparatus for exposing a substrate to a light image comprising:

a programmable light source for providing and modulating a plurality of substantially parallel optical beams, the optical beams modulated in response to an input data signal;

a beam shaper for narrowing the beams such that the beams comprise a central main lobe and at least one side; and

a movable stage for scanning the substrate through the narrowed array of beams in a direction slanted relative to the axes of the beam array.

22. Apparatus for exposing a substrate to a light image comprising:

a programmable light source for providing and modulating providing a plurality of substantially parallel optical beams, the optical beams modulated in response to an input data signal;

focusing optics positioned to received the optical beams for focusing the optical beams to form a spot-grid array pattern; and

a movable stage for scanning the substrate through the focused narrowed array of beams.

43. Apparatus as in claim 22 wherein the movable stage for scanning the substrate through the narrowed array of beams scans in a direction slanted relative to the axes of the beam array.

44. Apparatus as in claim 43 further comprising a beam shaper for narrowing the beams such that the beams comprise a central main lobe and at least one side.

23. A method comprising the steps of:

applying a memoryless resist to a substrate;

generating an array of substantially parallel light beams;

modulating a plurality of the light beams of the array for irradiating a substrate, the light beams modulated in response to an input signal corresponding to a predefined image to be recorded on the substrate;

moving the substrate on a movable stage in a direction slanted relative to the axes of the beam array while the generating, modulating steps are performed, such that the predefined image is recorded on the substrate.

24. The method of claim 23 wherein the optical beams overlap by integer fractions of a pixel width as they trace the continuous path on the substrate.

25. The method of claim 24 further comprising the step of periodically blanking blanks the optical beams when the stage is for moving the substrate such that an interleaved scan pattern is formed on substrate.

26. The method of claim 23, further comprising the step of compensating for positional errors in the movable stage.

27. The method of claim 23, comprising focusing the modulated light beams with an array of lenses after the modulating step.

28. The method of claim 23, comprising providing a fluid having a substantially optimized refractive index disposed in and filling a gap between the array of lenses and the substrate.

29. The method of claim 23, comprising moving the substrate substantially linearly in a scanning direction that deviates from an axis of the light beam array such that as the substrate is moved a distance substantially equal to a length of the array in the scanning direction, the modulated light beams trace a substantially continuous path on the substrate surface in a mechanical cross-scan direction.

30. A printer for exposing a substrate comprising:

a programmable light source for providing and modulating a plurality of substantially parallel optical beams in response to an input data signal; and

a movable stage for scanning the substrate through the optical beams.

31. A printer as in claim 30 further comprising focusing optics positioned to receive the narrowed beams for individually focusing the optical beams on a common image plane to form a spot-grid array pattern.

32. A printer as in claim 31 wherein the array is two dimensional.

45. Apparatus as in claim 32 wherein the movable stage for scanning the substrate through the array of beams scans in a direction slanted relative to the axes of the beam array.

46. Apparatus as in claim 45 further comprising a beam shaper for narrowing the optical beams and generating a main lobe and a corresponding side lobe for each beam.

33. A device for exposing a lithographic material, the lithographic material having the characteristic of being substantially memoryless after a predetermined period of time, the device comprising:

a light source;

a programmable two-dimensional spatial light modulator positioned to receive light from the light source for providing a parallel array of modulated light beams, the light beams modulated in response to an input data pattern signal;

a beam shaper array, with an element corresponding to each beam, for narrowing the optical beams, the narrowed optical beams characterized by a strong main lobe and lesser side lobes;

a focusing array, with an element corresponding to each beam, for focusing the narrowed modulated optical beams to form a spot array; and

a movable stage for introducing a relative movement between the lithographic material and the focusing optics such that the following conditions are meet;

a) the exposure time of imaged main lobes is sufficient to expose the lithographic material;

b) the exposure time of the imaged side lobes is not sufficient to individually expose the lithographic material; and

c) adjacent positions of the lithographic material are not exposed within the predetermined time period characterizing the lithographic material.

34. A device for exposing a lithographic material, the lithographic material having the characteristic of being substantially memoryless after a predetermined period of time, the device comprising:

an optical radiation source for providing an array of imaging beams and for modulating the optical beams in a sequence of desired patterns, the sequence of desired patterns corresponding to an image to be recorded on the lithographic material;

a beam shaper array, with an element corresponding to each beam, for narrowing each modulated optical beam, the narrowed optical beams characterized by a strong main lobe and lesser side lobes;

a focusing array, with an element corresponding to each beam, for focusing the narrowed modulated optical beams onto the lithographic material;

a movable stage for introducing a relative movement between the lithographic material and the beam shaper array such that the following conditions are meet;

a) the exposure time of imaged main lobes is sufficient to expose the lithographic material;

b) the exposure time of the imaged side lobes is not sufficient to expose the lithographic material;

c) adjacent positions of the lithographic material are not exposed within the predetermined time period characterizing the lithographic material; and

d) closest parallel scan lines are spaced apart by an integer fraction (px/n) of the pixel width, and sequential pixels exposed by a beam are spaced apart by an integer multiple of the pixel width (px*n).

35. A printer adapted for use with a substrate layered with a memoryless resist, the printer comprising:

a programmable optical radiation source for providing an array of substantially parallel optical beams, the optical beams individually modulated in response to the input signal;

focusing optics positioned to receive the modulated optical beams and for focusing the modulated optical beams; and

a movable stage for introducing a linear movement between the substrate and the focused modulated optical beams, the translation providing for a slanted scan.

36. The printer of claim 35, wherein the programmable optical radiation source provides a sequence of modulated optical beam arrays, each corresponding to an intermediate pattern on the substrate, and the superposition of the intermediate patterns forms a final image on the substrate.

37. The printer of claim 35 wherein the programmable optical radiation source comprises a light source and a spatial light modulator.

38. The printer of claim 36 wherein the light source comprises a pulsed light source.

39. A printer adapted for use with a substrate layered with a memoryless resist, the printer comprising:

an optical radiation source for providing an array of substantially parallel optical beams, the optical beam array forming a sequence of spot-grid array patterns;

optics positioned to receive the optical beam array and for focusing the optical beams onto the substrate; and

a movable stage for introducing a linear movement between the substrate and the focused optical beams in a direction slanted relative to the axes of the beam array, the translation synchronized with sequence of patterns for superimposing the patterns to form a final image on the substrate.

40. The printer of claim 39 wherein the optical radiation source comprises a microlens array.

41. A printer adapted for use with a substrate layered with a memoryless resist, the printer comprising:

an optical radiation source for providing an array of substantially parallel optical beams, the array of optical beams forming a spot-grid array pattern;

a beam shaper for narrowing the optical beams;

optics positioned to receive the narrowed modulated optical beams for focusing the narrowed modulated optical beams onto the substrate; and

a movable stage for introducing a linear movement between the substrate and the focused narrowed modulated optical beams, the translation providing for a slanted scan.

42. The printer of claim 41, wherein the optical radiation source provides a sequence of spot-grid array patterns, each corresponding to an intermediate pattern on the substrate, and the superposition of the intermediate patterns forms a final image on the substrate.