Claims
- 1. A process control target for a lithographic process which comprises:
an array having a plurality of elements of nominal width and nominal length, the elements having a line-end shape that is modified from the nominal width based on sensitivity to focus.
- 2. The process control target of claim 1, wherein the line-end is in the form of an anchor.
- 3. The process control target of claim 1, wherein the line-end is in the form of a nose.
- 4. The process control target of claim 1, wherein the line-end shape's width is larger than the nominal width of the line.
- 5. The process control target of claim 1, wherein the line-end shape's width is smaller than the than the nominal width of the line.
- 6. The process control target of claim 1, wherein the control target is a plurality of arrays.
- 7. The process control target of claim 1, wherein the line-end shape is modified with a sub-minimum resolution assist feature.
- 8. The process control target of claim 7, wherein the line-end shape is modified with serifs.
- 9. The process control target of claim 6, wherein one set of the arrays is a line end design and the second set is a space design.
- 10. The process control target of claim 9, wherein the line-ends for the line end design and the space design are noses.
- 11. The process control target of claim 9, wherein the line-ends for the line end design and the space design are anchors.
- 12. A process control target for a lithographic process which comprises:
an array having a plurality of elements of nominal width and nominal length, the elements having a line-end shape that is modified from the nominal width based on sensitivity to dose.
- 13. The process control target of claim 12, wherein the line-end is in the form of an anchor.
- 14. The process control target of claim 12, wherein the line-end shape's width is larger than the nominal width of the line.
- 15. The process control target of claim 1, wherein the line-end shape's width is smaller than the than the nominal width of the line.
- 16. The process control target of claim 12, wherein the line-end shape is modified with a sub-minimum resolution assist feature.
- 17. A method for determining the shape of an end-line shape for a process control target for a lithographic process comprising the steps of:
measuring the line and shape separation between a line-shortening space arrays and a line arrays having differing end-line shapes; selecting the appropriate sensitivity for dose or focus used in the lithographic process based on entries created using the line and shape separation measurements in a table.
- 18. The method claim 17, also comprising the step of using a parametric model to calculate entries in the lookup table.
- 19. The method of claim 18, also comprising the step of, selecting line-end bias according to coefficients contained in the table.
- 20. The method of claim 17 where the space and line arrays are maximized for best focus.
BACKGROUND OF THE INVENTION
[0001] This invention claims priority based on Provisional Patent Application No. 60/272,608 filed on Mar. 1, 2001.
Provisional Applications (1)
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Number |
Date |
Country |
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60272608 |
Mar 2001 |
US |