US6258610B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method analyzing a semiconductor surface using line width metrology with auto-correlation operation
Assignee: Nokia of America Corp
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Filing: 1999-07-02
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Granted: 2001-07-10
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Expires: 2019-07-02
Abstract
Abstract A method for analyzing a semiconductor surface having patterned features on the surface is disclosed. At least one patterned feature is scanned to produce a scanned waveform signal having signal segments corresponding to characteristic surface portions of the patterned feature. The signal segments are processed using an auto-correlation function to produce an auto-correlation signal for each characteristic surface portion of the patterned feature. A reference signal having signal segments corresponding to characteristic surface portions of a known patterned feature is provided and each segment of the auto-correlation signal is compared to the respective signal segments of the reference signal.
Inventors
- 👤 James W. Blatchford
- 👤 Scott Jessen
- 👤 Brittin C. Kane
- 👤 Nace Layadi
- 👤 John M. McIntosh
- 👤 Simon J. Molloy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:32
CPC Classifications
H; H10; H10P; H10P74/00; H10P74/20; H10P74/203
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
147 words
A method for analyzing a semiconductor surface having patterned features on the surface comprising the steps of: scanning at least one patterned feature to produce a scanned waveform signal having signal segments corresponding to characteristic surface portions of the patterned feature; processing the signal segments of the scanned waveform signal using an auto-correlation function to produce an auto-correlation signal for each characteristic surface portion of the patterned feature; providing a reference signal having signal segments corresponding to characteristic surface portions of a known patterned feature; and comparing each segment of the auto-correlation signal to the respective signal segments of the reference signal by cross-correlating at least one segment of the reference signal and the processed signal to form a cross-correlation signal and converting the cross-correlation signal to an inverse correlation signal to produce an assessment value for a segment corresponding to characteristic portions of the patterned feature.
Claim 2
Independent Claim
147 words
A method for analyzing a semiconductor surface having patterned features on the surface comprising the steps of: scanning at least one patterned feature to produce a scanned waveform signal having signal segments corresponding to characteristic surface portions of the patterned feature; processing the signal segments of the scanned waveform signal using an auto-correlation function to produce an auto-correlation signal for each characteristic surface portion of the patterned feature; providing a reference signal having signal segments corresponding to characteristic surface portions of a known patterned feature; and comparing each segment of the auto-correlation signal to the respective signal segments of the reference signal by cross-correlating at least one segment of the reference signal and the processed signal to form a cross-correlation signal and converting the cross-correlation signal to an inverse correlation signal to produce an assessment value for a segment corresponding to characteristic portions of the patterned feature.
Claim 3
Dependent Claim
28 words
The method according to claim 1 , and further comprising the step of determining that the patterned feature is acceptable if the assessment value is greater than 0.9.
Claim 4
Dependent Claim
27 words
The method according to claim 1 , and further comprising the step of determining that the substrate is acceptable if the assessment value is greater than 0.95.
Claim 5
Dependent Claim
23 words
The method according to claim 1 , and further comprising the step of adjusting a measurement tool in response to the comparing step.
Claim 6
Dependent Claim
22 words
A method according to claim 1 , and further comprising the step of scanning the semiconductor layer using a scanning electron microscope.
Claim 7
Dependent Claim
23 words
A method according to claim 1 , and further comprising the step of scanning the semiconductor layer using a semiconductor stylus measurement device.
Claim 8
Independent Claim
185 words
A method of manufacturing a semiconductor integrated circuit comprising the steps of: forming a semiconductor wafer having a surface with patterned features; scanning at least one patterned feature to produce a scanned waveform signal having the signal segments corresponding to characteristic surface portions of the patterned feature; processing the signal segments of the scanned waveform signal using an auto-correlation function to produce an auto-correlation signal for each characteristic portion of the patterned feature; providing a reference signal having signal segments corresponding to characteristic surface portions of a known patterned feature; comparing each segment of the auto-correlation signal to the respective signal segments of the reference signal by cross-correlating at least one segment of the reference signal and the processed signal to form a cross-correlation signal and converting the cross-correlation signal to an inverse correlation signal to produce an assessment value for a segment corresponding to characteristic portions of the patterned feature; determining if a segment is within predetermined assessment value relative to the respective signal segment of the reference signal; and rejecting the semiconductor wafer if the segment is not within a predetermined assessment value.
Claim 9
Independent Claim
185 words
A method of manufacturing a semiconductor integrated circuit comprising the steps of: forming a semiconductor wafer having a surface with patterned features; scanning at least one patterned feature to produce a scanned waveform signal having the signal segments corresponding to characteristic surface portions of the patterned feature; processing the signal segments of the scanned waveform signal using an auto-correlation function to produce an auto-correlation signal for each characteristic portion of the patterned feature; providing a reference signal having signal segments corresponding to characteristic surface portions of a known patterned feature; comparing each segment of the auto-correlation signal to the respective signal segments of the reference signal by cross-correlating at least one segment of the reference signal and the processed signal to form a cross-correlation signal and converting the cross-correlation signal to an inverse correlation signal to produce an assessment value for a segment corresponding to characteristic portions of the patterned feature; determining if a segment is within predetermined assessment value relative to the respective signal segment of the reference signal; and rejecting the semiconductor wafer if the segment is not within a predetermined assessment value.
Claim 10
Dependent Claim
28 words
The method according to claim 7 , and further comprising the step of determining that the patterned feature is acceptable if the assessment value is greater than 0.9.
Claim 11
Dependent Claim
27 words
The method according to claim 7 , and further comprising the step of determining that the substrate is acceptable if the assessment value is greater than 0.95.
Claim 12
Dependent Claim
23 words
The method according to claim 7 , and further comprising the step of adjusting a measurement tool in response to the comparing step.
Claim 13
Dependent Claim
22 words
A method according to claim 7 , and further comprising the step of scanning the semiconductor layer using a scanning electron microscope.
Claim 14
Dependent Claim
23 words
A method according to claim 7 , and further comprising the step of scanning the semiconductor layer using a semiconductor stylus measurement tool.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-07-09 | 2005-01-08 | 2005-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-07-09 | 2009-01-08 | 2009-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-07-09 | 2013-01-08 | 2013-07-10 | $7700.00 | Window Closed / Lapsed |