Granted Patent B2

US 7,586,620 · App. 12/262,375 · Granted Sep 8, 2009

Assignee: Zygo Corporation

Abstract

Claims (87)

1. A method for determining a spatial property of an object, the method comprising:

providing a low coherence interference signal obtained from a first object using an interferometer; and

determining a spatial property of the first object based upon the low coherence interference signal and a template,

wherein the template comprises contributions derived from each of a plurality of second low coherence interference signals,

wherein each of the plurality of second low coherence interference signals results from a respective, different point of a reference object, and

wherein the first object comprises a glass plate for a liquid crystal display and a first interface and a second interface and the plurality of second low coherence interference signals are obtained from a portion of the reference object having a single reflective interface.

2. A process for manufacturing a liquid crystal display using the method of claim 1 , the process comprising:

providing the first object, where the first object comprises a component of the liquid crystal display;

determining the spatial property of the first object using the method of claim 1 ;

modifying the first object based on the determined spatial property; and

producing the liquid crystal display using the component from the modified first object.

3. The process of claim 2 , wherein the first and second interfaces of the first object define a liquid crystal cell gap, and the spatial property is information about the cell gap.

4. The process of claim 3 , wherein the first object is modified by modifying the cell gap.

5. The process of claim 3 , wherein producing the liquid crystal display comprises filling the cell gap of the modified first object with liquid crystal.

6. The method of claim 2 , wherein the template is indicative of a response of the interferometer.

7. The method of claim 2 , wherein the first interface is an outer surface and the determining comprises determining a relative height of a point of the outer surface.

8. The method of claim 2 , wherein:

providing the low coherence interference signal comprises providing a plurality of low coherence interference signals each obtained from a corresponding different point of the first object using the interferometer; and

determining the spatial property comprises determining a spatial property of each of the different points based upon the corresponding low coherence interference signal and the template.

9. The method of claim 8 , wherein the plurality of low coherence interference signals were each obtained by steps comprising imaging a portion of the object using the interferometer.

10. The method of claim 8 , wherein the first interface is an outer surface and the spatial property of each of the different points is a height of each point.

11. The method of claim 2 , wherein first object comprises a photoresist and the spatial property is a spatial property of the photoresist.

12. A method for determining a spatial property of an object, the method comprising:

providing a low coherence interference signal obtained from a first object using an interferometer; and

determining a spatial property of the first object based upon the low coherence interference signal and a template indicative of a response of the interferometer,

wherein the first object comprises a glass plate for a liquid crystal display and the template is asymmetric.

13. A process for manufacturing a liquid crystal display using the method of claim 12 , the process comprising:

providing the first object, where the first object comprises a component of the liquid crystal display;

determining the spatial property of the first object using the method of claim 12 ;

modifying the first object based on the determined spatial property; and

producing the liquid crystal display using the component from the modified first object.

14. The process of claim 13 , wherein the first and second interfaces of the first object define a liquid crystal cell gap, and the spatial property is information about the cell gap.

15. The process of claim 14 , wherein the first object is modified by modifying the cell gap.

16. The process of claim 14 , wherein producing the liquid crystal display comprises filling the cell gap of the modified first object with liquid crystal.

17. The method of claim 13 , wherein the template has a shape of a truncated interference pattern.

18. The method of claim 13 , wherein the low coherence interference signal comprises overlapping interference patterns resulting from first and second interfaces of the object and the determining a spatial property comprises determining a spatial property of at least one of the first and second interfaces.

19. The method of claim 18 , wherein the first interface is an outer surface of the object and determining comprises determining a spatial property of the outer surface.

20. The method of claim 19 , wherein a shape of the template corresponds to a portion of the low coherence interference signal dominated by contributions from the first interface as opposed to the second interface.

21. The method of claim 13 , wherein first object comprises a photoresist and the spatial property is a spatial property of the photoresist.

22. A method for determining a spatial property of an object, the method comprising:

providing a low coherence interference signal obtained from a first object using an interferometer; and

determining a spatial property of the first object based upon the low coherence interference signal and a template,

wherein the template comprises contributions derived from each of a plurality of second low coherence interference signals,

wherein each of the plurality of second low coherence interference signals results from a respective, different point of a reference object,

wherein the first object comprises a glass plate for a liquid crystal display and each of the plurality of second low coherence interference signals includes object-height dependent properties indicative of a height of the corresponding reference object point, and wherein the method comprises generating the template, and the generating the template comprises removing contributions from the object-height dependent properties.

23. A process for manufacturing a liquid crystal display using the method of claim 22 , the process comprising:

providing the first object, where the first object comprises a component of the liquid crystal display;

determining the spatial property of the first object using the method of claim 22 ;

modifying the first object based on the determined spatial property; and

producing the liquid crystal display using the component from the modified first object.

24. The process of claim 23 , wherein the first and second interfaces of the first object define a liquid crystal cell gap, and the spatial property is information about the cell gap.

25. The process of claim 24 , wherein the first object is modified by modifying the cell gap.

26. The process of claim 24 , wherein producing the liquid crystal display comprises filling the cell gap of the modified first object with liquid crystal.

27. The method of claim 23 , wherein first object comprises a photoresist and the spatial property is a spatial property of the photoresist.

28. The method of claim 23 , wherein each second low coherence interference signal has a phase-related property indicative of the height of the corresponding reference object point and the removing contributions comprises removing the phase-related property.

29. The method of claim 23 , wherein the first and reference objects are the same.

30. The method of claim 23 , wherein the first object comprises a substrate comprising an overlying thin film and the plurality of second low coherence interference signals are obtained from a portion of the reference object having a single reflective interface.

31. A method for determining a spatial property of an object, the method comprising:

providing a low coherence interference signal obtained from a first object using an interferometer; and

determining a spatial property of the first object based upon the low coherence interference signal and a template indicative of a response of the interferometer, comprising cross-correlating the template and the low coherence interference signal,

wherein the first object comprises a glass plate for a liquid crystal display.

32. A process for manufacturing a liquid crystal display using the method of claim 31 , the process comprising:

providing the first object, where the first object comprises a component of the liquid crystal display;

determining the spatial property of the first object using the method of claim 31 ;

modifying the first object based on the determined spatial property; and

producing the liquid crystal display using the component from the modified first object.

33. The process of claim 32 , wherein the first and second interfaces of the first object define a liquid crystal cell gap, and the spatial property is information about the cell gap.

34. The process of claim 33 , wherein the first object is modified by modifying the cell gap.

35. The process of claim 34 , wherein producing the liquid crystal display comprises filling the cell gap of the modified first object with liquid crystal.

36. The method of claim 32 , wherein first object comprises a photoresist and the spatial property is a spatial property of the photoresist.

37. The method of claim 32 , wherein the cross-correlating comprises normalizing based upon a shape of the low coherence interference signal.

38. The method of claim 32 , wherein the cross-correlation is a partially complex cross-correlation.

39. A method for determining a spatial property of an object, the method comprising:

providing a low coherence interference signal obtained from a first object using an interferometer;

determining a spatial property of the first object based upon the low coherence interference signal and a template indicative of a response of the interferometer, and

comparing the template and the low coherence interference signal,

wherein the first object comprises a glass plate for a liquid crystal display and the comparing comprises determining a location within the low coherence interference signal and the determining a spatial property comprises processing a portion of the low coherence interference signal located to one side of the location.

40. A process for manufacturing a liquid crystal display using the method of claim 39 , the process comprising:

providing the first object, where the first object comprises a component of the liquid crystal display;

determining the spatial property of the first object using the method of claim 39 ;

modifying the first object based on the determined spatial property; and

producing the liquid crystal display using the component from the modified first object.

41. The process of claim 40 , wherein the first and second interfaces of the first object define a liquid crystal cell gap, and the spatial property is information about the cell gap.

42. The process of claim 41 , wherein the first object is modified by modifying the cell gap.

43. The process of claim 42 , wherein producing the liquid crystal display comprises filling the cell gap of the modified first object with liquid crystal.

44. The method of claim 40 , wherein first object comprises a photoresist and the spatial property is a spatial property of the photoresist.

45. The method of claim 40 , comprising transforming the low coherence interference signal.

Assignments (1)

Continuity (8)