US6397165B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microscopic corner radius measurement system
Assignee: KLA Tencor Technologies Corp
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Filing: 2001-06-07
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Granted: 2002-05-28
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Expires: 2021-06-07
Abstract
Abstract A measurement tool connects to a microscope for identifying and measuring microscopic dimensions of features on a photographic mask such as area, diameter and corner radius. Dimensions of features having sizes of less than about twice the wavelength being used (less than 1 micron for visible light) are measured quickly and accurately. The radius of curvature is also determined at submicron sizes using a flux measurement. Determination of the expected flux of a perfect comer aids in the measurement.
Inventors
- 👤 Peter J. Fiekowsky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 18:01
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/95; G01N21/956; G03; G03F; G03F1/00; G03F1/68; G03F1/82; G03F1/84
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
101 words
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.
Claim 2
Independent Claim
101 words
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.
Claim 3
Dependent Claim
23 words
A method as recited in claim 1 wherein said radius of curvature is less than about twice the wavelength used in said method.
Claim 4
Dependent Claim
59 words
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.
Claim 5
Dependent Claim
32 words
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.
Claim 6
Dependent Claim
48 words
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.
Claim 7
Dependent Claim
112 words
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.
Claim 8
Dependent Claim
112 words
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.
Claim 9
Dependent Claim
24 words
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.
Claim 10
Dependent Claim
53 words
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.
Claim 11
Dependent Claim
39 words
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.
Claim 12
Dependent Claim
44 words
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.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2005-05-27 | 2005-11-26 | 2006-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2009-05-27 | 2009-11-26 | 2010-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-05-27 | 2013-11-26 | 2014-05-28 | $7700.00 | Window Closed / Lapsed |