US6544699B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method to improve accuracy of model-based optical proximity correction
Assignee: GlobalFoundries Inc
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Filing: 2001-02-07
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Granted: 2003-04-08
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Expires: 2021-02-07
Abstract
Abstract The disclosure describes an exemplary method of improving the accuracy of model-based optical proximity correction (OPC). This method can include identifying best exposure dose and best focus conditions, measuring critical dimensions at the identified conditions, measuring critical dimensions at variations from the identified conditions, and obtaining critical dimension information by averaging measured critical dimensions.
Inventors
- 👤 Hung-Eil Kim
- 👤 Carl P. Babcock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:51
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/36; G03F7/00; G03F7/70; G03F7/70483; G03F7/70605; G03F7/70616; G03F7/70625
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
49 words
A method of improving the accuracy of model-based optical proximity correction (OPC), the method comprising: identifying best exposure dose and best focus conditions; measuring critical dimensions at the identified conditions; measuring critical dimensions at variations from the identified conditions; and obtaining critical dimension information by averaging measured critical dimensions.
Claim 2
Independent Claim
49 words
A method of improving the accuracy of model-based optical proximity correction (OPC), the method comprising: identifying best exposure dose and best focus conditions; measuring critical dimensions at the identified conditions; measuring critical dimensions at variations from the identified conditions; and obtaining critical dimension information by averaging measured critical dimensions.
Claim 3
Dependent Claim
38 words
The method of claim 1 , wherein the step of measuring critical dimensions at variations from the identified conditions comprises measuring critical dimensions at exposure dose conditions which vary by +/−5% from the identified best exposure dose condition.
Claim 4
Dependent Claim
37 words
The method of claim 1 , wherein the step of measuring critical dimensions at variations from the identified conditions comprises measuring critical dimensions at focus conditions which vary by +/−0.1 μm from the identified best focus condition.
Claim 5
Dependent Claim
13 words
The method of claim 1 , further comprising creating a sample empirical model.
Claim 6
Dependent Claim
14 words
The method of claim 1 , further comprising making a new standard test design.
Claim 7
Dependent Claim
40 words
The method of claim 5 , wherein the new standard test design includes an original test design, a larger critical dimension (CD) design from the original test design, and a smaller critical dimension (CD) design from the original test design.
Claim 8
Dependent Claim
19 words
The method of claim 6 , wherein the larger CD design is 4% larger than the original test design.
Claim 9
Dependent Claim
19 words
The method of claim 6 , wherein the smaller CD design is 4% smaller than the original test design.
Claim 10
Dependent Claim
24 words
The method of claim 1 , wherein the step of identifying best exposure dose and best focus conditions comprises using an exposure-focus matrix wafer.
Claim 11
Independent Claim
119 words
A method of improving the critical dimension (CD) measurement error on integrated circuit wafers and mask CD errors on reticles in an integrated circuit fabrication process, the method comprising: selecting a condition which provides a best exposure dose and a best focus; measuring critical dimensions on an integrated circuit wafer and on a reticle at the selected condition; measuring critical dimensions on the integrated circuit wafer and on the reticle at a different exposure dose than the best exposure dose; measuring critical dimensions on the integrated circuit wafer and on the reticle at a different focus than the best focus; and averaging measured critical dimensions at the selected condition, at the different exposure dose, and at the difference focus.
Claim 12
Independent Claim
119 words
A method of improving the critical dimension (CD) measurement error on integrated circuit wafers and mask CD errors on reticles in an integrated circuit fabrication process, the method comprising: selecting a condition which provides a best exposure dose and a best focus; measuring critical dimensions on an integrated circuit wafer and on a reticle at the selected condition; measuring critical dimensions on the integrated circuit wafer and on the reticle at a different exposure dose than the best exposure dose; measuring critical dimensions on the integrated circuit wafer and on the reticle at a different focus than the best focus; and averaging measured critical dimensions at the selected condition, at the different exposure dose, and at the difference focus.
Claim 13
Dependent Claim
19 words
The method of claim 10 , wherein the different exposure dose is ±5% from the selected best exposure dose.
Claim 14
Dependent Claim
18 words
The method of claim 10 , wherein the different focus is ±0.01 μm from the selected best focus.
Claim 15
Dependent Claim
18 words
The method of claim 10 , further comprising providing a sample empirical model from the averaged critical dimensions.
Claim 16
Dependent Claim
19 words
The method of claim 13 , further comprising providing a new standard test design from the sample empirical model.
Claim 17
Dependent Claim
34 words
The method of claim 14 , further comprising running the new standard test design for a larger critical dimension design and for a smaller critical dimension design to check possible effects of mask error.
Claim 18
Independent Claim
46 words
A method of improving critical dimension (CD) errors in an integrated circuit fabrication process, the method comprising: selecting an exposure dose and focus at a best condition; and measuring critical dimensions at various exposure dose and focus conditions including the selected exposure dose and focus condition.
Claim 19
Independent Claim
46 words
A method of improving critical dimension (CD) errors in an integrated circuit fabrication process, the method comprising: selecting an exposure dose and focus at a best condition; and measuring critical dimensions at various exposure dose and focus conditions including the selected exposure dose and focus condition.
Claim 20
Dependent Claim
26 words
The method of claim 16 , wherein the step of selecting an exposure dose and focus at a best condition comprises using an exposure-focus matrix wafer.
Claim 21
Dependent Claim
18 words
The method of claim 16 , further comprising creating a sample empirical model using the measured critical dimensions.
Claim 22
Dependent Claim
19 words
The method of claim 18 , further comprising running the sample empirical model at a larger critical dimension design.
Claim 23
Dependent Claim
19 words
The method of claim 18 , further comprising running the sample empirical model at a smaller critical dimension design.
References Cited (Backward Citations)
US5976741A
Cited
US6156463A
Cited
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 7.5 Years (Year 8) | 2010-04-07 | 2010-10-07 | 2011-04-08 | $3760.00 | Window Closed / Lapsed |
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