Lithographic Apparatus and Device Manufacturing Method

• US 20080297747A1
• Filed: 07/09/2008
• Published: 12/04/2008
• Est. Priority Date: 09/22/2003
• Status: Active Grant

• Current Assignee: ASML Netherlands BV (ASML Holding NV)
• Original Assignee: ASML Holding NV, ASML Netherlands BV (ASML Holding NV)
• Inventors: Franken, Dominicus Jacobus Petrus Adrianus, Troost, Kars Zeger, Kochersperger, Peter C., BLEEKER, Arno Jan
• Granted Patent: US 8,159,647 B2
• Time in Patent Office: Days
• US Class Current: 355/52
• 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 7/703 Non-planar pattern areas or non-planar masks, e.g. curved masks or substrates
• CPC Class Codes: G03F 7/707 Chucks, e.g. chucking or un-chucking operations or structural details
• CPC Class Codes: G03F 7/70783 Handling stress or warp of chucks, masks or workpieces, e.g. to compensate for imaging errors or considerations related to warpage of masks or workpieces due to their own weight

Abstract

One or more patterning arrays are mounted to a mounting plate via height adjustment structures that enable the flatness of the active surfaces of the patterning arrays to be controlled. The height adjustment structures may comprise an array of piezoelectric actuators or screws. Alternatively, the backside of the patterning means may be polished to optical flatness and bonded by crystal bonding to an optically flat surface of a rigid mounting body.

Claims

1. A lithographic apparatus, comprising:

an illumination system configured to supply a beam of radiation;

a patterning array of individually controllable elements configured to pattern the beam; and

a projection system configured to project the patterned beam onto a target portion of a substrate,

wherein the patterning array comprises,

a plurality of active elements disposed on a first surface of a substrate,

a second surface of the substrate opposite the first substrate being optically flat, and

a rigid body having an optically flat surface to which the second surface of the substrate is coupled.

2. The apparatus of claim 1, wherein the rigid body is mounted to a mounting plate configured to adjust a global tilt of the patterning arrays.

3. The apparatus of claim 2, wherein the rigid body is mounted to the mounting plate such that it is configured to substantially prevent distortion of the patterning array in the event of thermal expansion or contraction of the mounting plate.

4. The apparatus of claim 1, wherein the second surface of the substrate is coupled to the flat surface of the rigid body using one of direct crystal bonding or ansprengen.

5. A device manufacturing method, comprising:

patterning a beam of radiation using an active surface of a patterning array;

projecting the patterned beam onto a target portion of a substrate that is at least partially covered by a layer of radiation sensitive material; and

mounting the patterning array to a mounting plate or rigid body in such a manner as to ensure the active surface is substantially flat.

6. A device manufacturing method using a maskless lithography system, the method comprising:

illuminating a patterning array assembly having a plurality of patterning arrays, wherein the patterning array assembly is in a first orientation in a first plane;

adjusting a position of at least one patterning array in the patterning array assembly from the first orientation in the first plane to a second orientation; and

exposing an object with the patterned light from the patterning array assembly.

7. The method of claim 6, wherein:

the first plane is coplanar with at least one other patterning array in the patterning array assembly, and

the second orientation is not coplanar with the at least one other patterning array.

8. The method of claim 6, wherein the second orientation is a second plane.

9. The method of claim 6, wherein the second orientation is parallel to the first plane.

10. The method of claim 6, wherein the second orientation is tilted at an angle with respect to the first plane.

11. The method of claim 6, wherein the second orientation is curved with respect to the first plane.

12. The method of claim 6, wherein the position of the at least one patterning array is adjusted to compensate for focal deviation of the patterned light at the object.

13. The method of claim 6, wherein the position of the at least one patterning array is adjusted actively.

14. The method of claim 6, wherein the position of the at least one patterning array is adjusted using pistons.

15. The method of claim 6, wherein the method is performed during an initial setup of the maskless lithography system.

16. The method of claim 6, wherein the method is performed periodically for maintenance of the maskless lithography system.

17. A device manufacturing method using a maskless lithography system, comprising:

illuminating a patterning array assembly including patterning arrays, wherein each of the patterning arrays has a first position;

adjusting a first one of the patterning arrays from the first position to a second position;

transmitting light from the patterning array assembly through an optical system; and

exposing an object with the transmitted light,

wherein the first position is coplanar with the patterning arrays in the patterning array assembly and the second position is not coplanar with the patterning array assembly.

18. The method of claim 17, wherein the second position is parallel to the first position.

19. The method of claim 17, wherein the adjusting step comprises tilting the first one of the patterning arrays.

20. The method of claim 17, wherein the adjusting step comprises bending the first one of the patterning arrays.

21. A device manufacturing method using a maskless lithography system having a plurality of patterning arrays in a patterning array assembly, the patterning array assembly having a reflective surface, the method comprising:

adjusting a position of at least one of the plurality of patterning arrays based on a detected aberration;

illuminating the patterning array assembly;

transmitting light reflected by the patterning array assembly through an optical system; and

exposing an object with the light,

wherein the adjusting step causes the reflective surface of the patterning array assembly to deviate from a flat plane.

22. The method of claim 21, wherein the adjusting step comprises:

receiving exposure data at a plane of the object;

determining corrective adjustment needed for the at least one of the plurality of patterning arrays, wherein the adjustment is based on the exposure data; and

adjusting the at least one of the plurality of patterning arrays to reduce the aberration.

23. A maskless lithography system, comprising:

an illumination source configured to produce light; and

a patterning array assembly having patterning arrays, each patterning array in the patterning arrays being coupled to a respective adjuster;

an optics system configured to condition the light,

wherein each of the respective adjusters moves a respective one of the patterning arrays to correct for an optical aberration in the light received by the object, such that a surface of the patterning array assembly deviates from a flat plane.

24. The system of claim 23, wherein the aberration is total focus deviation.

25. The system of claim 23, wherein the adjuster is a set of adjusters.

26. The system of claim 25, wherein the set of adjusters tilts a respective one of the patterning arrays.

27. The system of claim 25, wherein the set of adjusters bends a respective one of the patterning arrays.

28. The system of claim 25, wherein the set of adjusters changes an elevation of a respective one of the patterning arrays.

29. The system of claim 25, further comprising:

a controller that controls the adjusters.

30. The system of claim 29, wherein the adjusters are pistons.

31. The system of claim 25, wherein the adjusters are screws.