Claims
- 1. A method of determining the radius of curvature of a microscopic corner feature located on a medium, said method comprising:determining the location of the perfect corner of said corner feature; calculating an expected flux value for a region of interest around said corner feature assuming that said corner feature were the perfect corner; calculating an actual flux value for said corner region of interest around said corner feature; calculating an eroded area flux value from said expected flux value and said actual flux value; and calculating the radius of curvature of said corner feature using said eroded area flux value.
- 2. A method as recited in claim 1 wherein said radius of curvature is less than about twice the wavelength used in said method.
- 3. A method as recited in claim 1 wherein said step of determining the location of the perfect corner includes the sub-steps of:defining a vertical and a horizontal region of interest across edges that define said corner feature; and determining an X-Y coordinate position for said location of the perfect corner using said vertical and horizontal regions of interest.
- 4. A method as recited in claim 1 further comprising:defining said corner region of interest around said corner feature using rough approximations for the X-Y coordinate positions of said perfect corner location.
- 5. A method as recited in claim 1 wherein said step of calculating an expected flux value includes the sub-step of:calculating an expected flux value for said region of interest around said corner feature using a background intensity and a foreground intensity of said corner region of interest.
- 6. A computer-readable medium comprising computer code for determining the radius of curvature of a microscopic corner feature located on a medium, said computer code of said computer-readable medium effecting the following:determining the location of the perfect corner of said corner feature; calculating an expected flux value for a region of interest around said corner feature assuming that said corner feature were the perfect corner; calculating an actual flux value for said corner region of interest around said corner feature; calculating an eroded area flux value from said expected flux value and said actual flux value; and calculating the radius of curvature of said corner feature using said eroded area flux value.
- 7. A computer-readable medium as recited in claim 6 wherein said radius of curvature is less than about twice the wavelength used in said method.
- 8. A computer-readable medium as recited in claim 6 further comprising computer code for effecting the following:defining a vertical and a horizontal region of interest across edges that define said corner feature; and determining an X-Y coordinate position for said location of the perfect corner using said vertical and horizontal regions of interest.
- 9. A computer-readable medium as recited in claim 6 further comprising computer code for effecting the following:defining said corner region of interest around said corner feature using rough approximations for the X-Y coordinate positions of said perfect corner location.
- 10. A computer-readable medium as recited in claim 6 further comprising computer code for effecting the following:calculating an expected flux value for said region of interest around said corner feature using a background intensity and a foreground intensity of said corner region of interest.
Parent Case Info
This application is a continuation-in-part of U.S. patent application Ser. No. 09/028,207 filed on Feb. 23, 1998 now U.S. Pat. No. 6,263,292, which in turns continuation-in-part of U.S. patent Ser. No. 08/807,789 filed on Feb. 28, 1997, now U.S. Pat. No. 5,966,677, both of which are incorporated by reference.
US Referenced Citations (6)
Non-Patent Literature Citations (6)
Entry |
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Continuation in Parts (2)
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Number |
Date |
Country |
Parent |
09/028207 |
Feb 1998 |
US |
Child |
09/877647 |
|
US |
Parent |
08/807789 |
Feb 1997 |
US |
Child |
09/028207 |
|
US |