US6049660A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Simulation method in lithographic process
Assignee: SK Hynix Inc
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Filing: 1997-12-24
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Granted: 2000-04-11
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Expires: 2017-12-24
Abstract
Abstract A simulation method for simulating in a lithographic process is disclosed, and the method can expect a size of a resist pattern by obtaining a diffused aerial image model(DAIM) by determining a simplified model in a aerial image to represent a resist process without simulating full processes including a resist process, and then applying the DAIM to a threshold model.
Inventors
- 👤 Chang Nam Ahn
- 👤 Hee Bom Kim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:31
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/70; G03F7/708; H; H10; H10P; H10P76/00; G03F1/00; G03F1/36; G03F7/20; G03F7/70483; G03F7/70491; G03F7/705
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
84 words
A simulation method in a lithography process, comprising the steps of: obtaining an aerial image by inputting exposure apparatus conditions and a mask layout in a resist process for I-lines; regarding said aerial image the same as an acid distribution being produced from a resist in an exposure process, and obtaining a diffused aerial image in consideration of diffusion of said acid in a post expose bake process; applying said diffused aerial image to a threshold model, thereby modeling an expected resist pattern size.
Claim 2
Dependent Claim
84 words
A simulation method in a lithography process, comprising the steps of: obtaining an aerial image by inputting exposure apparatus conditions and a mask layout in a resist process for I-lines; regarding said aerial image the same as an acid distribution being produced from a resist in an exposure process, and obtaining a diffused aerial image in consideration of diffusion of said acid in a post expose bake process; applying said diffused aerial image to a threshold model, thereby modeling an expected resist pattern size.
Claim 3
Dependent Claim
51 words
The simulation method as defined in claim 1, said aerial image is obtained by the following equation ##EQU14## where I 0 is said aerial image and F, F -1 represent Fourier transformation to ξ, n space, inverse Fourier transformation from ξ, n space, respectively, and σ B is a fitting parameter.
Claim 4
Dependent Claim
37 words
The simulation method as defined in claim 1, wherein said acid distribution is treated as that of two dimensions so that said aerial image is regarded the same as said acid distribution being produced from said resist.
Claim 5
Dependent Claim
40 words
The simulation method as defined in claim 1, wherein a thickness of said resist is determined to be less than 15,000 Å so that said aerial image is regarded the same as said acid distribution being produced from said resist.
Claim 6
Dependent Claim
86 words
A simulation method in a lithography process, comprising the steps of: obtaining an aerial image by inputting exposure apparatus conditions and a mask layout in a resist process for I-lines; regarding said aerial image the same as an acid distribution being produced from a resist in an exposure process, and obtaining a diffused aerial image in consideration of diffusion and amplification of said acid in a post expose bake process; applying said diffused aerial image to a threshold model, thereby modeling an expected resist pattern size.
Claim 7
Dependent Claim
86 words
A simulation method in a lithography process, comprising the steps of: obtaining an aerial image by inputting exposure apparatus conditions and a mask layout in a resist process for I-lines; regarding said aerial image the same as an acid distribution being produced from a resist in an exposure process, and obtaining a diffused aerial image in consideration of diffusion and amplification of said acid in a post expose bake process; applying said diffused aerial image to a threshold model, thereby modeling an expected resist pattern size.
Claim 8
Dependent Claim
51 words
The simulation method as defined in claim 5, said aerial image is obtained by the following equation ##EQU15## where I 0 is said aerial image and F, F -1 represent Fourier transformation to ξ, n space, inverse Fourier transformation from ξ, n space, respectively, and σ B is a fitting parameter.
Claim 9
Dependent Claim
37 words
The simulation method as defined in claim 5, wherein said acid distribution is treated as that of two dimensions so that said aerial image is regarded the same as said acid distribution being produced from said resist.
Claim 10
Dependent Claim
40 words
The simulation method as defined in claim 5, wherein a thickness of said resist is determined to be less than 15,000 Å so that said aerial image is regarded the same as said acid distribution being produced from said resist.
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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) | 2003-04-11 | 2003-10-11 | 2004-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-04-11 | 2007-10-11 | 2008-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-04-11 | 2011-10-11 | 2012-04-11 | $7700.00 | Window Closed / Lapsed |