Electroactive polymers for lithography

1. A lithographic method, comprising:

positioning a mask proximate to a substrate, the mask including a first mask section and a second mask section; and

shifting the first mask section relative to the substrate by actuating a first electroactive polymer member; and

shifting the second mask section relative to the substrate by actuating a second electroactive polymer member,

wherein the first mask section and the second mask section are shifted asynchronously.

2. The method of claim 1 , wherein shifting the first mask section relative to the substrate includes contacting the substrate with the first mask section.

3. The method of claim 2 , wherein shifting the second mask section relative to the substrate includes contacting the substrate with the second mask section subsequent to contacting the substrate with the first mask section.

4. The method of claim 1 , wherein shifting the first mask section relative to the substrate includes removing the first mask section from contact with the substrate.

5. The method of claim 4 , wherein shifting the second mask section relative to the substrate includes removing the second mask section from contact with the substrate subsequent to removing the first mask section from contact with the substrate.

6. The method of claim 1 , further comprising monitoring a contact force between the mask and the substrate.

7. The method of claim 6 , wherein monitoring contact force between the mask and the substrate includes monitoring contact force between the first mask section and the substrate.

8. The method of claim 1 , further comprising monitoring proximity between the mask and the substrate.

9. The method of claim 6 , wherein monitoring proximity between the mask and the substrate includes monitoring proximity between the first mask section and the substrate.

10. The method of claim 1 , wherein the first and second electroactive polymer members are integral.

11. A lithography apparatus, comprising:

a mask holder having a mask location, the mask holder being configured to hold a mask having a first mask section and a second mask section;

a substrate holder configured to hold a substrate in a substrate location in proximity to the mask location; and

a positioner configured to asynchronously shift the positions of the first mask section and the second mask section relative to the substrate by actuating an electroactive polymer.

12. The apparatus of claim 11 , wherein the positioner is configured to place the first mask section of a mask in the mask location in contact with a substrate in the substrate location.

13. The apparatus of claim 12 , wherein the positioner is further configured to place the second mask section of a mask in the mask location in contact with the substrate subsequent to placing the first mask section in contact with the substrate.

14. The apparatus of claim 11 , wherein the positioner is configured to remove the first mask section of a mask in the mask location from contact with a substrate in the substrate location.

15. The apparatus of claim 14 , wherein the positioner is further configured to remove the second mask section of a mask in the mask location from contact with the substrate subsequent to removing the first mask section from contact with the substrate.

16. The apparatus of claim 11 , further comprising a monitor configured to monitor a contact force between a mask in the mask location and a substrate in the substrate location.

17. The apparatus of claim 11 , further comprising a monitor configured to monitor a proximity between a mask in the mask location and a substrate in the substrate location.

18. A lithographic apparatus, comprising:

a mask holder having a mask location;

a substrate holder having a substrate location;

a monitor configured to monitor a liftoff force between a mask in the mask location and a substrate in the substrate location; and

a positioner configured to shift relative positions of the mask location and the substrate location responsive to the monitored liftoff force by actuating an electroactive polymer member.

19. The apparatus of claim 18 , wherein the monitor is configured to monitor liftoff force at a plurality of locations.

20. The apparatus of claim 18 , wherein the positioner is configured to shift relative positions of the mask location and the substrate location by actuating a plurality of active regions of the electroactive polymer member.

21. The apparatus of claim 18 , wherein the positioner is configured to minimize liftoff force as a mask in the mask position is removed from contact with a substrate in the substrate position.

22. A controller for a lithographic system, comprising:

a receiver that receives a liftoff force measurement signal;

a processor that uses the liftoff force measurement signal to determine an actuation profile for an electroactive polymer member; and

an output that actuates the electroactive polymer member according to the actuation profile.

23. The controller of claim 22 , wherein the liftoff force measurement signal is produced by measuring a liftoff force between a mask and a substrate.

24. The controller of claim 22 , wherein the liftoff force measurement signal comprises a plurality of liftoff force measurements.

25. The controller of claim 22 , wherein the actuation profile comprises a single degree of actuation of the electroactive polymer member.

26. The controller of claim 22 , wherein the actuation profile comprises a plurality of actuation signals, each actuation signal being directed to an active region of the electroactive polymer member.

27. The controller of claim 22 , wherein the actuation profile is selected to separate a mask and a substrate.

28. The controller of claim 22 , wherein the actuation profile is selected to reduce a liftoff force between a mask and a substrate.

29. A lithographic method, comprising:

positioning a mask proximate to a substrate;

monitoring a liftoff force between the mask and the substrate; and

shifting the mask relative to the substrate by actuating an electroactive polymer member, responsive to the monitored liftoff force.

30. The method of claim 29 , wherein monitoring the liftoff force includes monitoring liftoff force at a plurality of locations.

31. The method of claim 29 , wherein shifting the mask relative to the substrate includes actuating a plurality of active regions of the electroactive polymer member.

32. The method of claim 29 , wherein shifting the mask relative to the substrate includes minimizing a liftoff force as the mask is removed from contact with the substrate.

33. A lithographic method, comprising:

monitoring a contact force between a mask and a substrate; and

laterally shifting at least a portion of the mask in response to the monitored contact force, wherein shifting includes actuating an electroactive polymer member.

34. The method of claim 33 , wherein the contact force is normal to the substrate.

35. The method of claim 33 , wherein the contact force is parallel to the substrate.

36. The method of claim 33 , wherein actuating the electroactive polymer member includes applying a lateral force sufficient to overcome friction associated with a normal contact force.

37. The method of claim 33 , wherein laterally shifting the at least a portion of the mask includes laterally shifting the at least a portion of the mask by a predetermined distance.

38. The method of claim 33 , wherein laterally shifting the at least a portion of the mask includes laterally shifting the at least a portion of the mask at a predetermined speed.

39. The method of claim 33 , wherein laterally shifting the at least a portion of the mask includes maintaining the contact force within a predetermined range during lateral shifting.

40. The method of claim 33 , wherein laterally shifting the at least a portion of the mask includes laterally shifting the at least a portion of the mask while the mask is in contact with the substrate.

41. The method of claim 33 , wherein laterally shifting the at least a portion of the mask includes laterally shifting the at least a portion of the mask while the mask is not in contact with the substrate.

42. A lithographic apparatus, comprising:

a mask holder having a mask location;

a substrate holder having a substrate location;

a monitor configured to monitor a contact force between a mask in the mask location and a substrate in the substrate location; and

a positioner configured to laterally shift relative positions of at least a portion of the mask and the substrate responsive to the monitored contact force by actuating an electroactive polymer member.

43. The lithographic apparatus of claim 42 , wherein the monitored contact force is normal to a substrate in the substrate holder.

44. The lithographic apparatus of claim 42 , wherein the monitored contact force is parallel to a substrate in the substrate holder.

45. The lithographic apparatus of claim 42 , wherein the positioner is configured to overcome friction associated with a normal contact force between a mask in the mask position and a substrate in the substrate position.

46. The lithographic apparatus of claim 42 , wherein the positioner is configured to laterally shift the relative positions of the at least a portion of the mask and the substrate by a predetermined distance.

47. The lithographic apparatus of claim 42 , wherein the positioner is configured to laterally shift the relative positions of the at least a portion of the mask and the substrate at a predetermined speed.

48. The lithographic apparatus of claim 42 , wherein the positioner is configured to maintain the contact force within a predetermined range while laterally shifting the relative positions of the at least a portion of the mask and the substrate.

49. The lithographic apparatus of claim 42 , wherein the positioner is configured to laterally shift the relative positions of the at least a portion of the mask and the substrate while maintaining contact between the mask and the substrate.

50. The lithographic apparatus of claim 42 , wherein the positioner is configured to remove contact between the at least a portion of the mask and the substrate before laterally shifting the relative positions of the at least a portion of the mask and the substrate.