Claims
- 1. A method for correcting the figure of a multilayer coated substrate, comprising removing at least a portion of a multilayer coating from a multilayer coated substrate by an amount needed to mitigate surface height error.
- 2. The method of claim 1, wherein said multilayer coating comprises a Mo/Si multilayer.
- 3. The method of claim 1, wherein the step of removing material is carried out by directed energetic particles at said multilayer coating.
- 4. The method of claim 3, wherein said energetic particles are provided by an energy source selected from the group consisting of an ion beam and an electron beam.
- 5. The method of claim 1, wherein the step of removing at least a portion of a multilayer coating includes depositing energy into said multilayer coating.
- 6. The method of claim 1, wherein the step of removing at least a portion of a multilayer coating includes depositing thermal energy into said multilayer coating.
- 7. The method of claim 6, wherein the step of depositing thermal energy includes depositing laser energy.
- 8. The method of claim 6, wherein the step of depositing thermal energy includes bombarding said region with an electron beam.
- 9. The method of claim 6, wherein the step of depositing thermal energy includes bombarding said region with an ion beam.
- 10. The method of claim 1, wherein the step of removing at least a portion of a multilayer coating comprises bombarding said region with atoms.
- 11. The method of claim 7, wherein the step of depositing laser energy is carried out with an excimer laser.
- 12. The method of claim 1, wherein removal of material in said region is localized to at least one area delineated by spatial extent.
- 13. The method of claim 12, wherein said at least one area comprises pixels
- 14. The method of claim 1, wherein the step of removing at least a portion of a multilayer coating is controlled as a function of time.
- 15. The method of claim 6, wherein the step of depositing thermal energy is controlled as a function of time wherein a desired height change is proportional to the duration of the step of depositing thermal energy.
- 16. The method of claim 6, wherein the step of removing at least a portion of a multilayer coating is controlled as a function of the intensity of energy deposited into said region.
- 17. The method of claim 13, wherein said pixels comprise an abrupt spatial boundary.
- 18. The method of claim 17, wherein said abrupt spatial boundary comprises a geometric shape.
- 19. The method of claim 13, wherein said pixels comprise a non-abrupt spatial boundary.
- 20. An apparatus for correcting the figure of a multilayer coated substrate, comprising:
an interferometer for measuring the figure of a multilayer coated substrate with a surface that has a height error; and a mechanism for removing material from the multilayer of said multilayer coated substrate.
- 21. The apparatus of claim 20, wherein said mechanism for removing material comprises an apparatus for depositing energy onto said multilayer coating.
- 22. The apparatus of claim 25, wherein said apparatus for depositing energy comprises a laser.
- 23. The apparatus of claim 25, wherein said apparatus for depositing energy comprises an ion beam source.
- 24. The apparatus of claim 25, wherein said apparatus for depositing energy comprises an electron beam source.
- 25. The apparatus of claim 25, wherein said apparatus for depositing energy comprises an atomic beam source.
- 26. The apparatus of claim 22, wherein said multilayer comprises alternating layers of Molybdenum and Silicon.
- 27. The apparatus of claim 22, wherein said laser comprises an excimer laser.
- 28. A method for correcting the figure of a multilayer coated optic, comprising:
measuring the figure of multilayer coated optic; and removing material from said multilayer coated optic to obtain a desired figure.
- 29. An apparatus for correcting the figure of a multilayer coated optic, comprising:
means for measuring the figure of said optic; and means for removing material from the multilayer coating on said multilayer-coated optic to obtain a desired figure.
- 30. A method for optimizing the performance of an EUVL system having multilayer coated reflective optics, comprising:
measuring, at a plurality of locations, the wavefront of a beam of light propagating within said EUVL system to determine figure error corrections to one or more of the mirrors that would improve the system wavefront; removing individual multilayer coated optics from said system; removing material from said individual multilayer coated optics to obtain a desired figure; and placing said individual multilayer-coated optics back into said system.
Government Interests
[0001] The United States Government has rights in this invention pursuant to Contract No. W-7405-ENG-48 between the United States Department of Energy and the University of California for the operation of Lawrence Livermore National Laboratory.