Lithographic projection mask, device manufacturing method, and device manufactured thereby

• US 20040156027A1
• Filed: 12/19/2003
• Published: 08/12/2004
• Est. Priority Date: 12/19/2002
• Status: Active Grant

• Current Assignee: ASML Netherlands BV (ASML Holding NV)
• Original Assignee: ASML Netherlands BV (ASML Holding NV)
• Inventors: Friz, Alexander, Consolini, Joseph J., Best, Keith Frank
• Granted Patent: US 7,019,814 B2
• Time in Patent Office: Days
• US Class Current: 355/53
• CPC Class Codes: G03F 9/7076 Mark details, e.g. phase grating mark, temporary mark
• CPC Class Codes: G03F 9/7084 Position of mark on substrate, i.e. position in (x, y, z) of mark, e.g. buried or resist covered mark, mark on rearside, at the substrate edge, in the circuit area, latent image mark, marks in plural levels

Abstract

A method according to one embodiment of the invention may be used in determining relative positions of developed patterns on a substrate (exposed e.g. using the step mode). Such a method uses reference marks which are located within or even superimposed on device patterns. Also disclosed is a mask of a lithographic projection apparatus including reference marks that may be used in such a method.

Claims

1. A device manufacturing method comprising:

projecting an image onto a first target portion of a radiation-sensitive material that at least partially covers a substrate, the image including a device pattern and at least one reference mark located within the device pattern;

projecting said image, including the device pattern and at least one reference mark, onto a second target portion of the radiation-sensitive material; and

determining a relative placement of the first and second target portions based on a relative position of the reference marks in the first and second target portions.

2. The device manufacturing method according to claim 1, wherein the device pattern extends around the at least one reference mark.

3. The device manufacturing method according to claim 1, wherein said determining a relative placement is based on a relative position of two reference marks that are not superposed.

4. The device manufacturing method according to claim 1, wherein said projecting an image includes using a patterning structure to pattern a beam of radiation according to the device pattern.

5. The device manufacturing method according to claim 1, wherein the image includes two reference marks positioned along a line that bisects the device pattern.

6. The device manufacturing method according to claim 5, wherein the image includes two reference marks positioned along a first line that bisects the device pattern, and

wherein the image includes two reference marks positioned along a second line that bisects the device pattern and has a different direction than the first line.

7. The device manufacturing method according to claim 1, said method further comprising developing the radiation-sensitive material to form a plurality of developed patterns on the substrate.

8. The device manufacturing method according to claim 7, said method further comprising determining that the patterns are misaligned, based on the relative placement;

and

removing a exposed portion and an unexposed portion of the layer of radiation-sensitive material, based on said determining that the patterns are misaligned.

9. The device manufacturing method according to claim 1, said method further comprising determining that the first and second target portions are misaligned, based on the relative placement;

and

removing a exposed portion and an unexposed portion of the layer of radiation-sensitive material, based on said determining that the target portions are misaligned.

10. The device manufacturing method according to claim 1, further comprising projecting the image onto a third target portion of the radiation-sensitive material, said projecting the image onto a third target portion being based on a result of said determining a relative placement.

11. The device manufacturing method according to claim 1, wherein said projecting the image onto a second target portion of the radiation-sensitive material includes projecting the image onto a plurality of target portions of the radiation-sensitive material, each of the plurality of target portions being adjacent to the first target portion, and

wherein the first target portion includes a plurality of regions, each of the plurality of regions corresponding to one of the plurality of adjacent target portions and being adjacent to that target portion, and

wherein each of the plurality of regions includes at least one reference mark.

12. The device manufacturing method according to claim 11, wherein at least one of the plurality of adjacent target portions at least partially overlaps the corresponding region.

13. A device manufactured according to the method according to claim 1.

14. A lithographic projection mask, said mask comprising:

a device pattern, and

at least one reference mark located within the device pattern.

15. The lithographic projection mask according to claim 14, wherein the device pattern extends around the at least one reference mark.

16. The lithographic projection mask according to claim 14, wherein the mask includes two reference marks positioned along a line that bisects the device pattern.

17. The lithographic projection mask according to claim 14, wherein the mask includes two reference marks positioned along a first line that bisects the device pattern, and

wherein the mask includes two reference marks positioned along a second line that bisects the device pattern and has a different direction than the first line.

18. A data storage medium including instructions describing a device manufacturing method, said method comprising:

projecting an image onto a first target portion of a radiation-sensitive material that at least partially covers a substrate, the image including a device pattern and at least one reference mark located within the device pattern;

projecting said image, including the device pattern and at least one reference mark, onto a second target portion of the radiation-sensitive material; and

determining a relative placement of the first and second target portions based on a relative position of the reference marks in the first and second target portions.

19. The data storage medium according to claim 18, wherein said projecting an image includes using a patterning structure to pattern a beam of radiation according to the device pattern.

20. The data storage medium according to claim 18, said method further comprising developing the radiation-sensitive material to form a plurality of developed patterns on the substrate.

21. The data storage medium according to claim 20, said method further comprising determining that the patterns are misaligned, based on the relative placement;

and

removing a exposed portion and an unexposed portion of the layer of radiation-sensitive material, based on said determining that the patterns are misaligned.

22. The data storage medium according to claim 18, said method further comprising determining that the first and second target portions are misaligned, based on the relative placement;

and

removing a exposed portion and an unexposed portion of the layer of radiation-sensitive material, based on said determining that the target portions are misaligned.

23. The data storage medium according to claim 18, further comprising projecting the image onto a third target portion of the radiation-sensitive material, said projecting the image onto a third target portion being based on a result of said determining a relative placement.

24. The data storage medium according to claim 18, wherein said projecting the image onto a second target portion of the radiation-sensitive material includes projecting the image onto a plurality of target portions of the radiation-sensitive material, each of the plurality of target portions being adjacent to the first target portion, and

wherein the first target portion includes a plurality of regions, each of the plurality of regions corresponding to one of the plurality of adjacent target portions and being adjacent to that target portion, and

wherein each of the plurality of regions includes at least one reference mark.

25. The data storage medium according to claim 24, wherein at least one of the plurality of adjacent target portions at least partially overlaps the corresponding region.

26. A device manufacturing method comprising:

projecting an image onto a first target portion of a radiation-sensitive material that at least partially covers a substrate, the image including at least one reference mark;

projecting the image onto a second target portion of the radiation-sensitive material; and

determining a relative placement of the first and second target portions based on a relative position of a reference mark in the first target portion and a reference mark in the second target portion, wherein the two reference marks do not overlap one another.

27. The device manufacturing method according to claim 26, wherein said projecting an image includes using a patterning structure to pattern a beam of radiation according to the device pattern.

28. The device manufacturing method according to claim 26, said method further comprising developing the radiation-sensitive material to form a plurality of developed patterns on the substrate.

29. The device manufacturing method according to claim 28, said method further comprising determining that the patterns are misaligned, based on the relative placement;

and

removing a exposed portion and an unexposed portion of the layer of radiation-sensitive material, based on said determining that the patterns are misaligned.

30. The device manufacturing method according to claim 26, said method further comprising determining that the first and second target portions are misaligned, based on the relative placement;

and

removing a exposed portion and an unexposed portion of the layer of radiation-sensitive material, based on said determining that the target portions are misaligned.

31. The device manufacturing method according to claim 26, further comprising projecting the image onto a third target portion of the radiation-sensitive material, said projecting the image onto a third target portion being based on a result of said determining a relative placement.

32. The device manufacturing method according to claim 26, wherein said projecting the image onto a second target portion of the radiation-sensitive material includes projecting the image onto a plurality of target portions of the radiation-sensitive material, each of the plurality of target portions being adjacent to the first target portion, and

wherein the first target portion includes a plurality of regions, each of the plurality of regions corresponding to one of the plurality of adjacent target portions and being adjacent to that target portion, and

wherein each of the plurality of regions includes at least one reference mark.

33. The device manufacturing method according to claim 32, wherein at least one of the plurality of adjacent target portions at least partially overlaps the corresponding region.