US6091845A
Expired / Lapsed
US
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Inspection technique of photomask
Assignee: Micron Technology Inc
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Filing: 1998-02-24
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Granted: 2000-07-18
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Expires: 2018-02-24
Abstract
Abstract An improved technique for inspecting photomasks employs simulated images of the resist pattern. A simulated image of an original pattern is compared to a simulated image generated from a pattern captured from a photomask manufactured from the original pattern. Alternatively, simulated images generated from captured data from two different instances of the same original pattern formed in a photomask are compared.
Inventors
- 👤 Christophe Pierrat
- 👤 James Burdorf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 09:18
CPC Classifications
G; G06; G06T; G06T7/00; G06T7/0002; G06T7/0004; G06T7/0006; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/95; G01N21/956; G01N21/95607; G03; G03F; G03F1/00; G03F1/68; G03F1/82; G03F1/84; G03F7/00; G03F7/70; G03F7/70483; G06T2207/00; G06T2207/30; G06T2207/30108; G06T2207/30148
Claims Analysis
Total Claims: 44
Claim 1
Independent Claim
140 words
A method of inspecting a mask, comprising: acquiring mask image data from the mask; modifying the acquired mask image data according to characteristics of resist material at different deposition elevations and producing therefrom acquired mask elevation image data, wherein the modification includes: applying a first common elevation to a mask area of the acquired mask image data; applying a second elevation to an unmasked area of the acquired mask image data; and interpolating an edge between the mask area and the unmask area of the acquired mask image data at the first common elevation; generating a first image simulation of the acquired mask elevation image data; acquiring image pattern data from a pattern used for forming the mask; generating a second image simulation of the acquired image pattern data; and comparing the first and second image simulations for a defect.
Claim 2
Independent Claim
140 words
A method of inspecting a mask, comprising: acquiring mask image data from the mask; modifying the acquired mask image data according to characteristics of resist material at different deposition elevations and producing therefrom acquired mask elevation image data, wherein the modification includes: applying a first common elevation to a mask area of the acquired mask image data; applying a second elevation to an unmasked area of the acquired mask image data; and interpolating an edge between the mask area and the unmask area of the acquired mask image data at the first common elevation; generating a first image simulation of the acquired mask elevation image data; acquiring image pattern data from a pattern used for forming the mask; generating a second image simulation of the acquired image pattern data; and comparing the first and second image simulations for a defect.
Claim 3
Dependent Claim
14 words
The method of claim 1, wherein the first and second image simulations are two-dimensional.
Claim 4
Dependent Claim
14 words
The method of claim 1, wherein the first and second image simulations are three-dimensional.
Claim 5
Dependent Claim
22 words
The method of claim 1, wherein at least generating a first image simulation and generating a second image simulation is performed off-line.
Claim 6
Independent Claim
140 words
A method of inspecting a mask, comprising: acquiring mask image data from the mask; generating a first image simulation of the acquired mask image data; acquiring pattern image data from a pattern used for forming the mask; modifying the acquired pattern image data according to characteristics of resist material at different deposition elevations and producing therefrom acquired pattern elevation data, wherein the modification includes: applying a first common elevation to a mask area of the acquired pattern image data; applying a second common elevation to an unmasked area of the acquired pattern image data; and interpolating an edge between the mask area and the unmasked area of the acquired pattern image data at the first common elevation; generating a second image simulation of the acquired pattern elevation image data; and comparing the first and second image simulations for a defect.
Claim 7
Independent Claim
140 words
A method of inspecting a mask, comprising: acquiring mask image data from the mask; generating a first image simulation of the acquired mask image data; acquiring pattern image data from a pattern used for forming the mask; modifying the acquired pattern image data according to characteristics of resist material at different deposition elevations and producing therefrom acquired pattern elevation data, wherein the modification includes: applying a first common elevation to a mask area of the acquired pattern image data; applying a second common elevation to an unmasked area of the acquired pattern image data; and interpolating an edge between the mask area and the unmasked area of the acquired pattern image data at the first common elevation; generating a second image simulation of the acquired pattern elevation image data; and comparing the first and second image simulations for a defect.
Claim 8
Dependent Claim
14 words
The method of claim 5, wherein the first and second image simulations are two-dimensional.
Claim 9
Dependent Claim
14 words
The method of claim 5, wherein the first and second image simulations are three-dimensional.
Claim 10
Dependent Claim
22 words
The method of claim 5, wherein at least generating a first image simulation and generating a second image simulation is performed off-line.
Claim 11
Independent Claim
161 words
A method of inspecting a mask, comprising: acquiring image data of a first pattern from the mask; modifying the image data of the first pattern according to characteristics of resist material at different deposition elevations and producing therefrom acquired first pattern elevation image data, wherein the modification includes: applying a first common elevation to a mask area of the acquired image data from the first pattern; applying a second common elevation to an unmasked area of the acquired image data from the first pattern; and interpolating an edge between the mask area and the unmasked area of the acquired image data from the first pattern of the mask at the first common elevation; generating a first image simulation of the acquired first pattern elevation image data; acquiring image data of a second pattern from the mask; generating a second image simulation of the acquired image data from the second pattern; and comparing the first and second image simulations for a defect.
Claim 12
Independent Claim
161 words
A method of inspecting a mask, comprising: acquiring image data of a first pattern from the mask; modifying the image data of the first pattern according to characteristics of resist material at different deposition elevations and producing therefrom acquired first pattern elevation image data, wherein the modification includes: applying a first common elevation to a mask area of the acquired image data from the first pattern; applying a second common elevation to an unmasked area of the acquired image data from the first pattern; and interpolating an edge between the mask area and the unmasked area of the acquired image data from the first pattern of the mask at the first common elevation; generating a first image simulation of the acquired first pattern elevation image data; acquiring image data of a second pattern from the mask; generating a second image simulation of the acquired image data from the second pattern; and comparing the first and second image simulations for a defect.
Claim 13
Independent Claim
161 words
A method of inspecting a mask, comprising: acquiring image data of a first pattern from the mask; generating a first image simulation of the acquired image data from the first pattern; acquiring image data of a second pattern from the mask; modifying the acquired image data of the second pattern according to characteristics of resist material at different deposition elevations and producing therefrom acquired second pattern elevation data, wherein the modification includes: applying a first common elevation to a mask area of the acquired image data from the second pattern; applying a second common elevation to an unmasked area of the acquired image data from the second pattern; and interpolating an edge between the mask area and the unmasked area of the acquired image data from the second pattern of the mask at the first common elevation; generating a second image simulation of the acquired second pattern elevation image data; and comparing the first and second image simulations for a defect.
Claim 14
Independent Claim
161 words
A method of inspecting a mask, comprising: acquiring image data of a first pattern from the mask; generating a first image simulation of the acquired image data from the first pattern; acquiring image data of a second pattern from the mask; modifying the acquired image data of the second pattern according to characteristics of resist material at different deposition elevations and producing therefrom acquired second pattern elevation data, wherein the modification includes: applying a first common elevation to a mask area of the acquired image data from the second pattern; applying a second common elevation to an unmasked area of the acquired image data from the second pattern; and interpolating an edge between the mask area and the unmasked area of the acquired image data from the second pattern of the mask at the first common elevation; generating a second image simulation of the acquired second pattern elevation image data; and comparing the first and second image simulations for a defect.
Claim 15
Dependent Claim
154 words
A computer readable medium on a computer, the computer readable medium having computer executable instructions for performing a method comprising: acquiring mask image data from a mask; modifying the acquired mask image data according to characteristics of resist material at different deposition elevations and producing therefrom acquired mask elevation image data, wherein the modification includes: applying a first common elevation to a mask area of the acquired mask image data; applying a second common elevation to an unmasked area of the acquired mask image data; and interpolating an edge between the mask area and the unmasked area of the acquired mask image data at the first common elevation; generating a first image simulation of the acquired mask elevation image data; acquiring image pattern data from a pattern used for forming the mask; generating a second image simulation of the acquired image pattern data; and comparing the first and second image simulations for a defect.
Claim 16
Dependent Claim
154 words
A computer readable medium on a computer, the computer readable medium having computer executable instructions for performing a method comprising: acquiring mask image data from a mask; modifying the acquired mask image data according to characteristics of resist material at different deposition elevations and producing therefrom acquired mask elevation image data, wherein the modification includes: applying a first common elevation to a mask area of the acquired mask image data; applying a second common elevation to an unmasked area of the acquired mask image data; and interpolating an edge between the mask area and the unmasked area of the acquired mask image data at the first common elevation; generating a first image simulation of the acquired mask elevation image data; acquiring image pattern data from a pattern used for forming the mask; generating a second image simulation of the acquired image pattern data; and comparing the first and second image simulations for a defect.
Claim 17
Dependent Claim
16 words
The computer readable medium of claim 11, wherein the first and second image simulations are two-dimensional.
Claim 18
Dependent Claim
16 words
The computer readable medium of claim 11, wherein the first and second image simulations are three-dimensional.
Claim 19
Dependent Claim
24 words
The computer readable medium of claim 11, wherein at least generating a first image simulation and generating a second image simulation is performed off-line.
Claim 20
Dependent Claim
153 words
A computer readable medium on a computer, the computer readable medium having computer executable instructions for performing a method comprising: acquiring mask image data from a mask; generating a first image simulation of the acquired mask image data; acquiring pattern image data from a pattern used for forming the mask; modifying the acquired pattern image data according to characteristics of resist material at different deposition elevations and producing therefrom acquired pattern elevation data, wherein the modification includes: applying a first common elevation to a mask area of the acquired pattern image data; applying a second common elevation to an unmasked area of the acquired pattern image data; and interpolating an edge between the mask area and the unmasked area of the acquired pattern image data at the first common elevation; generating a second image simulation of the acquired pattern elevation image data; and comparing the first and second image simulations for a defect.
Claim 21
Dependent Claim
153 words
A computer readable medium on a computer, the computer readable medium having computer executable instructions for performing a method comprising: acquiring mask image data from a mask; generating a first image simulation of the acquired mask image data; acquiring pattern image data from a pattern used for forming the mask; modifying the acquired pattern image data according to characteristics of resist material at different deposition elevations and producing therefrom acquired pattern elevation data, wherein the modification includes: applying a first common elevation to a mask area of the acquired pattern image data; applying a second common elevation to an unmasked area of the acquired pattern image data; and interpolating an edge between the mask area and the unmasked area of the acquired pattern image data at the first common elevation; generating a second image simulation of the acquired pattern elevation image data; and comparing the first and second image simulations for a defect.
Claim 22
Dependent Claim
16 words
The computer readable medium of claim 15, wherein the first and second image simulations are two-dimensional.
Claim 23
Dependent Claim
16 words
The computer readable medium of claim 15, wherein the first and second image simulations are three-dimensional.
Claim 24
Dependent Claim
24 words
The computer readable medium of claim 15, wherein at least generating a first image simulation and generating a second image simulation is performed off-line.
Claim 25
Dependent Claim
175 words
A computer readable medium on a computer, the computer readable medium having computer executable instructions for performing a method comprising: acquiring image data of a first pattern from a mask; modifying the acquired image data from the first pattern according to characteristics of resist material at different deposition elevations and producing therefrom acquired first pattern elevation image data, wherein the modification includes: applying a first common elevation to a mask area of the acquired image data from the first pattern; applying a second common elevation to an unmasked area of the acquired image data from the first pattern; and interpolating an edge between the mask area and the unmasked area of the acquired image data from the first pattern of the mask at the first common elevation; generating a first image simulation of the acquired first pattern elevation image data; acquiring image data of a second pattern from the mask; generating a second image simulation of the acquired image data from the second pattern; and comparing the first and second image simulations for a defect.
Claim 26
Dependent Claim
175 words
A computer readable medium on a computer, the computer readable medium having computer executable instructions for performing a method comprising: acquiring image data of a first pattern from a mask; modifying the acquired image data from the first pattern according to characteristics of resist material at different deposition elevations and producing therefrom acquired first pattern elevation image data, wherein the modification includes: applying a first common elevation to a mask area of the acquired image data from the first pattern; applying a second common elevation to an unmasked area of the acquired image data from the first pattern; and interpolating an edge between the mask area and the unmasked area of the acquired image data from the first pattern of the mask at the first common elevation; generating a first image simulation of the acquired first pattern elevation image data; acquiring image data of a second pattern from the mask; generating a second image simulation of the acquired image data from the second pattern; and comparing the first and second image simulations for a defect.
Claim 27
Dependent Claim
174 words
A computer readable medium on a computer, the computer readable medium having computer executable instructions for performing a method comprising: acquiring image data of a first pattern from a mask; generating a first image simulation of the acquired image data from the first pattern; acquiring image data of a second pattern from the mask; modifying the acquired image data from the second pattern according to characteristics of resist material at different deposition elevations and producing therefrom acquired second pattern elevation data, wherein the modification includes: applying a first common elevation to a mask area of the acquired image data from the second pattern; applying a second common elevation to an unmasked area of the acquired image data from the second pattern; and interpolating an edge between the mask area and the unmasked area of the acquired image data from the second pattern of the mask at the first common elevation; generating a second image simulation of the acquired second pattern elevation image data; and comparing the first and second image simulations for a defect.
Claim 28
Dependent Claim
174 words
A computer readable medium on a computer, the computer readable medium having computer executable instructions for performing a method comprising: acquiring image data of a first pattern from a mask; generating a first image simulation of the acquired image data from the first pattern; acquiring image data of a second pattern from the mask; modifying the acquired image data from the second pattern according to characteristics of resist material at different deposition elevations and producing therefrom acquired second pattern elevation data, wherein the modification includes: applying a first common elevation to a mask area of the acquired image data from the second pattern; applying a second common elevation to an unmasked area of the acquired image data from the second pattern; and interpolating an edge between the mask area and the unmasked area of the acquired image data from the second pattern of the mask at the first common elevation; generating a second image simulation of the acquired second pattern elevation image data; and comparing the first and second image simulations for a defect.
Claim 29
Dependent Claim
189 words
A mask inspection system, comprising: a mask having a plurality of identical patterns, including a first pattern and a second pattern; an inspection machine operable for acquiring image data of the first pattern and for acquiring image data of the second pattern and for producing therefrom first acquired image data and second acquired image data, respectively; a processor operable for modifying the first acquired image data according to characteristics of resist material at different deposition elevations and producing therefrom first acquired elevation image data, wherein the modification includes: applying a first common elevation to a mask area of the first acquired image data; applying a second common elevation to an unmasked area of the first acquired image data; and interpolating an edge between the mask area and the unmasked area of the first acquired image data at the first common elevation; the processor further operable for creating a first simulated image using the first acquired elevation image data; the processor further operable for creating a second simulated image using the second acquired image data; and the processor further operable for comparing the first and second simulated images for defects.
Claim 30
Dependent Claim
189 words
A mask inspection system, comprising: a mask having a plurality of identical patterns, including a first pattern and a second pattern; an inspection machine operable for acquiring image data of the first pattern and for acquiring image data of the second pattern and for producing therefrom first acquired image data and second acquired image data, respectively; a processor operable for modifying the first acquired image data according to characteristics of resist material at different deposition elevations and producing therefrom first acquired elevation image data, wherein the modification includes: applying a first common elevation to a mask area of the first acquired image data; applying a second common elevation to an unmasked area of the first acquired image data; and interpolating an edge between the mask area and the unmasked area of the first acquired image data at the first common elevation; the processor further operable for creating a first simulated image using the first acquired elevation image data; the processor further operable for creating a second simulated image using the second acquired image data; and the processor further operable for comparing the first and second simulated images for defects.
Claim 31
Dependent Claim
16 words
The mask inspection system of claim 21, wherein the first and second simulated images are two-dimensional.
Claim 32
Dependent Claim
16 words
The mask inspection system of claim 21, wherein the first and second simulated images are three-dimensional.
Claim 33
Dependent Claim
31 words
The mask inspection system of claim 21, wherein the processor is further operable for modifying at least the first acquired image data and the second acquired image data using convolution algorithms.
Claim 34
Dependent Claim
25 words
The mask inspection system of claim 21, wherein the processor creates at least one of the first simulated image and the second simulated image off-line.
Claim 35
Dependent Claim
190 words
A mask inspection system, comprising: a mask having a plurality of identical patterns, including a first pattern and a second pattern; an inspection machine operable for acquiring image data of the first pattern and for acquiring image data of the second pattern and for producing therefrom first acquired image data and second acquired image data, respectively; a processor operable for modifying the second acquired image data according to characteristics of resist material at different deposition elevations and producing therefrom second acquired elevation image data, wherein the modification includes: applying a first common elevation to a mask area of the second acquired image data; applying a second common elevation to an unmasked area of the second acquired image data; and interpolating an edge between the mask area and the unmasked area of the second acquired image data at the first common elevation; the processor further operable for creating a first simulated image using the first acquired mask image data; the processor further operable for creating a second simulated image using the second acquired elevation image data; and the processor further operable for comparing the first and second simulated images for defects.
Claim 36
Dependent Claim
190 words
A mask inspection system, comprising: a mask having a plurality of identical patterns, including a first pattern and a second pattern; an inspection machine operable for acquiring image data of the first pattern and for acquiring image data of the second pattern and for producing therefrom first acquired image data and second acquired image data, respectively; a processor operable for modifying the second acquired image data according to characteristics of resist material at different deposition elevations and producing therefrom second acquired elevation image data, wherein the modification includes: applying a first common elevation to a mask area of the second acquired image data; applying a second common elevation to an unmasked area of the second acquired image data; and interpolating an edge between the mask area and the unmasked area of the second acquired image data at the first common elevation; the processor further operable for creating a first simulated image using the first acquired mask image data; the processor further operable for creating a second simulated image using the second acquired elevation image data; and the processor further operable for comparing the first and second simulated images for defects.
Claim 37
Dependent Claim
16 words
The mask inspection system of claim 26, wherein the first and second simulated images are two-dimensional.
Claim 38
Dependent Claim
16 words
The mask inspection system of claim 26, wherein the first and second simulated images are three-dimensional.
Claim 39
Dependent Claim
31 words
The mask inspection system of claim 26, wherein the processor is further operable for modifying at least the first acquired image data and the second acquired image data using convolution algorithms.
Claim 40
Dependent Claim
25 words
The mask inspection system of claim 26, wherein the processor creates at least one of the first simulated image and the second simulated image off-line.
Claim 41
Dependent Claim
180 words
A mask inspection system, comprising: a mask fabricated from a pattern; an inspection machine operable for acquiring image data from the mask and producing therefrom acquired mask image data; a processor operable for modifying the acquired mask image data according to characteristics of resist material at different deposition elevations and producing therefrom acquired mask elevation image data, wherein the modification includes: applying a first common elevation to a mask area of the acquired mask image data; applying a second common elevation to an unmasked area of the acquired mask image data; and interpolating an edge between the mask area and the unmasked area of the acquired mask image data at the first common elevation; the processor further operable for creating a first simulated image using the acquired mask elevation image data; the processor further operable for acquiring image data from the pattern and producing therefrom acquired pattern image data; the processor further operable for creating a second simulated image using the acquired pattern image data; and the processor further operable for comparing the first and second simulated images for defects.
Claim 42
Dependent Claim
180 words
A mask inspection system, comprising: a mask fabricated from a pattern; an inspection machine operable for acquiring image data from the mask and producing therefrom acquired mask image data; a processor operable for modifying the acquired mask image data according to characteristics of resist material at different deposition elevations and producing therefrom acquired mask elevation image data, wherein the modification includes: applying a first common elevation to a mask area of the acquired mask image data; applying a second common elevation to an unmasked area of the acquired mask image data; and interpolating an edge between the mask area and the unmasked area of the acquired mask image data at the first common elevation; the processor further operable for creating a first simulated image using the acquired mask elevation image data; the processor further operable for acquiring image data from the pattern and producing therefrom acquired pattern image data; the processor further operable for creating a second simulated image using the acquired pattern image data; and the processor further operable for comparing the first and second simulated images for defects.
Claim 43
Dependent Claim
180 words
A mask inspection system, comprising: a mask fabricated from a pattern; an inspection machine operable for acquiring image data from the mask and producing therefrom acquired mask image data; a processor operable for creating a first simulated image using the acquired mask image data; the processor further operable for acquiring image data from the pattern and producing therefrom acquired pattern image data; the processor further operable for modifying the acquired pattern image data according to characteristics of resist material at different deposition elevations and producing therefrom acquired pattern elevation image data, wherein the modification includes: applying a first common elevation to a mask area of the acquired pattern image data; applying a second common elevation to an unmasked area of the acquired pattern image data; and interpolating an edge between the mask area and the unmasked area of the acquired pattern image data at the first common elevation; the processor further operable for creating a second simulated image using the acquired pattern elevation image data; and the processor further operable for comparing the first and second simulated images for defects.
Claim 44
Dependent Claim
180 words
A mask inspection system, comprising: a mask fabricated from a pattern; an inspection machine operable for acquiring image data from the mask and producing therefrom acquired mask image data; a processor operable for creating a first simulated image using the acquired mask image data; the processor further operable for acquiring image data from the pattern and producing therefrom acquired pattern image data; the processor further operable for modifying the acquired pattern image data according to characteristics of resist material at different deposition elevations and producing therefrom acquired pattern elevation image data, wherein the modification includes: applying a first common elevation to a mask area of the acquired pattern image data; applying a second common elevation to an unmasked area of the acquired pattern image data; and interpolating an edge between the mask area and the unmasked area of the acquired pattern image data at the first common elevation; the processor further operable for creating a second simulated image using the acquired pattern elevation image data; and the processor further operable for comparing the first and second simulated images for defects.
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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) | 2003-07-18 | 2004-01-17 | 2004-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-07-18 | 2008-01-17 | 2008-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-07-18 | 2012-01-17 | 2012-07-18 | $7700.00 | Window Closed / Lapsed |