Patent US6519501B2 successfully refreshed from Google Patents.
US6519501B2
Expired / Lapsed
US
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Method of determining optimum exposure threshold for a given photolithographic model
Assignee: Micron Technology Inc
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Filing: 2001-01-23
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Granted: 2003-02-11
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Expires: 2021-01-23
Abstract
Abstract A system and method for enhancing process latitude (tolerances) in the fabrication of devices and integrated circuits. A measuring point is selected corresponding to a feature of critical dimension. Then the pattern is convolved with the model, and its value and rate of change are calculated over a range of corresponding values of a first process parameter. Next, an optimum threshold having the largest rate of change, or contrast, is selected. Finally, proximity correction is performed using relevant parameters.
Inventors
- 👤 Christophe Pierrat
- 👤 James Burdorf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 09:16
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/70; G03F7/70483; G03F7/7055; G03F7/70558; C; C09; C09K; C09K8/00; C09K8/42; C09K8/50; C09K8/504; C09K8/506; C09K8/508; C09K8/60; C09K8/80; H; H10; H10P; H10P74/00; H10P74/23
Claims Analysis
Total Claims: 102
Claim 1
Independent Claim
97 words
A computer storage for storing instructions for determining an optimum process point for fabricating a device feature of a critical dimension, the instructions comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of a first process parameter representative of mask material edge position; selecting an optimum threshold value having the largest rate of change around said measuring point; and determining the first process parameter value corresponding to the optimum threshold value.
Claim 2
Dependent Claim
97 words
A computer storage for storing instructions for determining an optimum process point for fabricating a device feature of a critical dimension, the instructions comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of a first process parameter representative of mask material edge position; selecting an optimum threshold value having the largest rate of change around said measuring point; and determining the first process parameter value corresponding to the optimum threshold value.
Claim 3
Dependent Claim
36 words
The computer storage of claim 1 , wherein the instructions further include calculating the modeled behavior values and their rates of change over a range of corresponding values of the first process parameter representative of focus.
Claim 4
Dependent Claim
37 words
The computer storage of claim 1 , wherein the instructions further include calculating the modeled behavior values and their rates of change over a range of corresponding values of the first process parameter representative of numerical aperture.
Claim 5
Dependent Claim
59 words
The computer storage of claim 1 , wherein the instructions further include: selecting a point on one side of the measuring point; calculating a value of the modeled behavior at each of the points; and calculating a slope through each of the points, wherein the slope is a function of the values of the modeled behavior at each point.
Claim 6
Dependent Claim
16 words
The computer storage of claim 4 , wherein the instructions further include selecting a second point.
Claim 7
Dependent Claim
99 words
The computer storage of claim 1 , wherein the instructions further include: decrementing the value of the first process parameter; calculating the value of the modeled behavior at the measuring point; determining the value of the modeled behavior at a location offset from the measuring point in a first direction by a second value; determining the value of the modeled behavior at a location offset from the measuring point in a second direction, opposite to the first direction, by the second value; and calculating the rate of change of the modeled behavior corresponding to the first process parameter value.
Claim 8
Dependent Claim
43 words
The computer storage of claim 6 , wherein the instructions further include: calculating a difference of the modeled behavior values ascertained during determining the values of the modeled behavior; and dividing the difference of the modeled behavior values by twice the second value.
Claim 9
Dependent Claim
118 words
A computer storage for storing instructions for determining an optimum process point for fabricating a device feature of a critical dimension, the instructions comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of a first process parameter representative of mask material edge position; selecting an optimum threshold value having the largest rate of change around said measuring point; determining the first process parameter value corresponding to the optimum threshold value; and providing the optimum threshold value to a proximity effect correction process which modifies the mask pattern to compensate for proximity effects.
Claim 10
Dependent Claim
118 words
A computer storage for storing instructions for determining an optimum process point for fabricating a device feature of a critical dimension, the instructions comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of a first process parameter representative of mask material edge position; selecting an optimum threshold value having the largest rate of change around said measuring point; determining the first process parameter value corresponding to the optimum threshold value; and providing the optimum threshold value to a proximity effect correction process which modifies the mask pattern to compensate for proximity effects.
Claim 11
Dependent Claim
40 words
The computer storage of claim 8 , wherein the instructions further include calculating the modeled behavior values and their rates of change over a range of corresponding values of the first process parameter of a computer representation of a mask.
Claim 12
Dependent Claim
36 words
The computer storage of claim 8 , wherein the instructions further include calculating the modeled behavior values and their rates of change over a range of corresponding values of the first process parameter representative of focus.
Claim 13
Dependent Claim
37 words
The computer storage of claim 8 , wherein the instructions further include calculating the modeled behavior values and their rates of change over a range of corresponding values of the first process parameter representative of numerical aperture.
Claim 14
Dependent Claim
77 words
A computer storage for storing instructions for determining an optimum process point for fabricating a device feature of a critical dimension, the instructions comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding mask material edge positions; and selecting an optimum threshold value having the largest rate of change around said measuring point.
Claim 15
Dependent Claim
77 words
A computer storage for storing instructions for determining an optimum process point for fabricating a device feature of a critical dimension, the instructions comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding mask material edge positions; and selecting an optimum threshold value having the largest rate of change around said measuring point.
Claim 16
Dependent Claim
24 words
The computer storage of claim 12 , wherein the instructions further comprise determining the mask material edge position corresponding to the optimum threshold value.
Claim 17
Dependent Claim
59 words
The computer storage of claim 12 , wherein the instructions further comprise: selecting a point on one side of the measuring point; calculating a value of the modeled behavior at each of the points; and calculating a slope through each of the points, wherein the slope is a function of the values of the modeled behavior at each point.
Claim 18
Dependent Claim
101 words
The computer storage of claim 12 , wherein the instructions further comprise: shifting the mask material edge position by a first value; calculating the value of the modeled behavior at the measuring point; determining the value of the modeled behavior at a location offset from the measuring point in a first direction by a second value; determining the value of the modeled behavior at a location offset from the measuring point in a second direction, opposite the first direction, by the second value; and calculating the rate of change of the modeled behavior value corresponding to the mask material edge position.
Claim 19
Dependent Claim
42 words
The computer storage of claim 15 , wherein the instructions include: calculating a difference of the modeled behavior values ascertained during determining the values of the modeled behavior; and dividing the difference of the modeled behavior values by twice the second value.
Claim 20
Dependent Claim
35 words
The computer storage of claim 15 , wherein the instructions further comprise providing the optimum threshold value to a proximity effect correction process which modifies the mask material edge position to compensate for proximity effects.
Claim 21
Dependent Claim
228 words
A computer storage for storing instructions for determining an optimum process point for fabricating a device feature of a critical dimension, the instructions comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding mask material edge positions, the calculating modeled behavior values and their rates of change including: shifting the mask material edge position by a first value; calculating the value of the modeled behavior at the measuring point; determining the value of the modeled behavior at a location offset from the measuring point in a first direction by a second value; determining the value of the modeled behavior at a location offset from the measuring point in a second direction, opposite the first direction, by the second value; and calculating the rate of change of the threshold, the calculating the rate of change of the threshold including: calculating a difference of the modeled behavior values ascertained during determining the values of the modeled behavior; and dividing the difference of the modeled behavior values by twice the second value; selecting an optimum threshold value having the largest rate of change; and providing the optimum threshold value to a proximity effect correction process which modifies the mask material edge position to compensate for proximity effects.
Claim 22
Dependent Claim
228 words
A computer storage for storing instructions for determining an optimum process point for fabricating a device feature of a critical dimension, the instructions comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding mask material edge positions, the calculating modeled behavior values and their rates of change including: shifting the mask material edge position by a first value; calculating the value of the modeled behavior at the measuring point; determining the value of the modeled behavior at a location offset from the measuring point in a first direction by a second value; determining the value of the modeled behavior at a location offset from the measuring point in a second direction, opposite the first direction, by the second value; and calculating the rate of change of the threshold, the calculating the rate of change of the threshold including: calculating a difference of the modeled behavior values ascertained during determining the values of the modeled behavior; and dividing the difference of the modeled behavior values by twice the second value; selecting an optimum threshold value having the largest rate of change; and providing the optimum threshold value to a proximity effect correction process which modifies the mask material edge position to compensate for proximity effects.
Claim 23
Dependent Claim
124 words
A computer storage for storing instructions for determining an optimum process point for fabricating a device feature of critical dimension, the instructions comprising: selecting a plurality of measuring points, wherein each measuring point corresponds to the feature of the critical dimension; calculating values and rates of change of modeled behavior over a range of values of a first process parameter for each measuring point, the range of values representative of mask material edge position; selecting an optimum threshold value having the largest rate of change for each measuring point; selecting a threshold value from the plurality of optimum threshold values; and providing the selected threshold value to a proximity effect correction process which modifies the mask material edge position to compensate for proximity effects.
Claim 24
Dependent Claim
124 words
A computer storage for storing instructions for determining an optimum process point for fabricating a device feature of critical dimension, the instructions comprising: selecting a plurality of measuring points, wherein each measuring point corresponds to the feature of the critical dimension; calculating values and rates of change of modeled behavior over a range of values of a first process parameter for each measuring point, the range of values representative of mask material edge position; selecting an optimum threshold value having the largest rate of change for each measuring point; selecting a threshold value from the plurality of optimum threshold values; and providing the selected threshold value to a proximity effect correction process which modifies the mask material edge position to compensate for proximity effects.
Claim 25
Dependent Claim
25 words
The computer storage of claim 19 , wherein the instructions further include determining the mean of the selected optimum threshold values for each measuring point.
Claim 26
Dependent Claim
25 words
The computer storage of claim 19 , wherein the instructions further include determining the median of the selected optimum threshold values for each measuring point.
Claim 27
Dependent Claim
99 words
A computer for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: means for selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; means for calculating modeled behavior values and their rates of change over a range of corresponding values of a first process parameter representative of mask material edge position; means for selecting an optimum threshold value having the largest rate of change around said measuring point; and means for determining the first process parameter value corresponding to the optimum threshold value.
Claim 28
Dependent Claim
99 words
A computer for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: means for selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; means for calculating modeled behavior values and their rates of change over a range of corresponding values of a first process parameter representative of mask material edge position; means for selecting an optimum threshold value having the largest rate of change around said measuring point; and means for determining the first process parameter value corresponding to the optimum threshold value.
Claim 29
Dependent Claim
38 words
The computer of claim 22 , wherein the means for calculating includes means for calculating the modeled behavior values and their rates of change over a range of corresponding values of the first process parameter representative of focus.
Claim 30
Dependent Claim
42 words
The computer of claim 22 , wherein the means for calculating modeled behavior values includes means for calculating the modeled behavior values and their rates of change over a range of corresponding values of the first process parameter representative of numerical aperture.
Claim 31
Dependent Claim
65 words
The computer of claim 22 , wherein the means for calculating includes: means for selecting a point on one side of the measuring point; means for calculating a value of the modeled behavior at each of the points; and means for calculating a slope through each of the points, wherein the slope is a function of the values of the modeled behavior at each point.
Claim 32
Dependent Claim
19 words
The computer of claim 25 , wherein the means for calculating modeled behavior values includes selecting a second point.
Claim 33
Dependent Claim
116 words
The computer of claim 22 , wherein the means for calculating threshold values and their rates of change includes: means for decrementing the value of the first process parameter; means for calculating the value of the modeled behavior at the measuring point; means for determining the value of the modeled behavior at a location offset from the measuring point in a first direction by a second value; means for determining the value of the modeled behavior at a location offset from the measuring point in a second direction, opposite to the first direction, by the second value; and means for calculating the rate of change of the modeled behavior corresponding to the first process parameter value.
Claim 34
Dependent Claim
51 words
The computer of claim 27 , wherein the means for calculating the rate of change includes: means for calculating a difference of the modeled behavior values ascertained during determining the values of the modeled behavior; and means for dividing the difference of the modeled behavior values by twice the second value.
Claim 35
Independent Claim
207 words
A method, in a computer, for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of values of a first process parameter, including: decrementing a value of the first process parameter by a first value; calculating a value of the modeled behavior at the measuring point; determining a value of the modeled behavior at a location offset from the measuring point by a second value in a first direction; determining a value of the modeled behavior at a location offset from the measuring point by the second value in a second direction; and determining a rate of change of the modeled behavior; and determining whether a value and the rate of change of the modeled behavior has been calculated for a first process parameter equal to the first value, if so then end the method, and if not, then increment the first process parameter by a third value and repeat the above process in the order recited starting with calculating a value of the modeled behavior at the measuring period.
Claim 36
Independent Claim
207 words
A method, in a computer, for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of values of a first process parameter, including: decrementing a value of the first process parameter by a first value; calculating a value of the modeled behavior at the measuring point; determining a value of the modeled behavior at a location offset from the measuring point by a second value in a first direction; determining a value of the modeled behavior at a location offset from the measuring point by the second value in a second direction; and determining a rate of change of the modeled behavior; and determining whether a value and the rate of change of the modeled behavior has been calculated for a first process parameter equal to the first value, if so then end the method, and if not, then increment the first process parameter by a third value and repeat the above process in the order recited starting with calculating a value of the modeled behavior at the measuring period.
Claim 37
Dependent Claim
43 words
The method of claim 29 , further comprising selecting an optimum threshold value having a largest rate of change, and providing the optimum threshold value to a proximity effect correction process which modifies a mask material edge position to compensate for proximity effects.
Claim 38
Dependent Claim
20 words
The method of claim 29 , further comprising selecting the third value to be 2 −N times the first value.
Claim 39
Dependent Claim
28 words
The method of claim 29 , further comprising selecting the third value is chosen such that first value can be divided by the third value without a remainder.
Claim 40
Independent Claim
94 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of an optical parameter of a stepper with respect to a constant mask material edge; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining an optical parameter value corresponding to the optimum threshold value.
Claim 41
Independent Claim
94 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of an optical parameter of a stepper with respect to a constant mask material edge; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining an optical parameter value corresponding to the optimum threshold value.
Claim 42
Dependent Claim
36 words
The method of claim 33 , wherein calculating modeled behavior values comprises calculating the modeled behavior values and their rates of change over a range of corresponding values of the optical parameter representative of numerical aperture.
Claim 43
Dependent Claim
35 words
The method of claim 33 , wherein calculating modeled behavior values comprises calculating the modeled behavior values and their rates of change over a range of corresponding values of the optical parameter representative of focus.
Claim 44
Dependent Claim
59 words
The method of claim 33 , wherein calculating modeled behavior values comprises: selecting a point on one side of the measuring point; calculating a value of the modeled behavior at each of the points; and calculating a slope through each of the points, wherein the slope is a function of the values of the modeled behavior at each point.
Claim 45
Independent Claim
151 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of an optical parameter of a stepper with respect to a constant mask material edge; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining an optical parameter value corresponding to the optimum threshold value, wherein calculating modeled behavior values includes: selecting a point on one side of the measuring point; selecting a second point; calculating a value of the modeled behavior at each of the points; and calculating a slope through each of the points, wherein the slope is a function of the values of the modeled behavior at each point.
Claim 46
Independent Claim
151 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of an optical parameter of a stepper with respect to a constant mask material edge; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining an optical parameter value corresponding to the optimum threshold value, wherein calculating modeled behavior values includes: selecting a point on one side of the measuring point; selecting a second point; calculating a value of the modeled behavior at each of the points; and calculating a slope through each of the points, wherein the slope is a function of the values of the modeled behavior at each point.
Claim 47
Independent Claim
182 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of an optical parameter of a stepper; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining an optical parameter value corresponding to the optimum threshold value, wherein calculating modeled behavior values and their rates of change includes: decrementing a value of the optical parameter; calculating a value of the modeled behavior at the measuring point; determining a value of the modeled behavior at a location offset from the measuring point in a first direction by a second value; determining a value of the modeled behavior at a location offset from the measuring point in a second direction, opposite to the first direction, by the second value; and calculating a rate of change of the modeled behavior corresponding to the optical parameter value.
Claim 48
Independent Claim
182 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of an optical parameter of a stepper; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining an optical parameter value corresponding to the optimum threshold value, wherein calculating modeled behavior values and their rates of change includes: decrementing a value of the optical parameter; calculating a value of the modeled behavior at the measuring point; determining a value of the modeled behavior at a location offset from the measuring point in a first direction by a second value; determining a value of the modeled behavior at a location offset from the measuring point in a second direction, opposite to the first direction, by the second value; and calculating a rate of change of the modeled behavior corresponding to the optical parameter value.
Claim 49
Dependent Claim
44 words
The method of claim 38 , wherein calculating the rate of change comprises: calculating a difference of the modeled behavior values ascertained during determining the values of the modeled behavior; and dividing the difference of the modeled behavior values by twice the second value.
Claim 50
Dependent Claim
36 words
The method of claim 33 , wherein selecting a measuring point, calculating modeled behavior values and their rates of change, selecting an optimum threshold value, and determining an optical parameter value are performed in a computer.
Claim 51
Independent Claim
115 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of an optical parameter of a stepper with respect to a constant mask material edge; selecting an optimum threshold value having a largest rate of change around the measuring point; determining an optical parameter value corresponding to the optimum threshold value; and providing the optimum threshold value to a proximity effect correction process which modifies a mask pattern to compensate for proximity effects.
Claim 52
Independent Claim
115 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of an optical parameter of a stepper with respect to a constant mask material edge; selecting an optimum threshold value having a largest rate of change around the measuring point; determining an optical parameter value corresponding to the optimum threshold value; and providing the optimum threshold value to a proximity effect correction process which modifies a mask pattern to compensate for proximity effects.
Claim 53
Dependent Claim
50 words
The method of claim 41 , wherein calculating modeled behavior values comprises calculating the modeled behavior values and their rates of change over a range of corresponding values of the optical parameter representative of one of focus, numerical aperture, exposure time, and on or off axis settings of a stepper.
Claim 54
Dependent Claim
53 words
The method of claim 41 , wherein selecting a measuring point, calculating modeled behavior values and their rates of change, selecting an optimum threshold value, determining an optical parameter value corresponding to the optimum threshold value; and providing the optimum threshold value to a proximity effect correction process are performed in a computer.
Claim 55
Independent Claim
92 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of exposure time of a stepper with respect to a constant mask material edge; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining the exposure time corresponding to the optimum threshold value.
Claim 56
Independent Claim
92 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of exposure time of a stepper with respect to a constant mask material edge; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining the exposure time corresponding to the optimum threshold value.
Claim 57
Dependent Claim
59 words
The method of claim 44 , wherein calculating modeled behavior values comprises: selecting a point on one side of the measuring point; calculating a value of the modeled behavior at each of the points; and calculating a slope through each of the points, wherein the slope is a function of the values of the modeled behavior at each point.
Claim 58
Independent Claim
149 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of exposure time of a stepper with respect to a constant mask material edge; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining the exposure time corresponding to the optimum threshold value, wherein calculating modeled behavior values includes: selecting a point on one side of the measuring point; selecting a second point; calculating a value of the modeled behavior at each of the points; and calculating a slope through each of the points, wherein the slope is a function of the values of the modeled behavior at each point.
Claim 59
Independent Claim
149 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of exposure time of a stepper with respect to a constant mask material edge; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining the exposure time corresponding to the optimum threshold value, wherein calculating modeled behavior values includes: selecting a point on one side of the measuring point; selecting a second point; calculating a value of the modeled behavior at each of the points; and calculating a slope through each of the points, wherein the slope is a function of the values of the modeled behavior at each point.
Claim 60
Independent Claim
178 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of exposure time of a stepper; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining the exposure time corresponding to the optimum threshold value, wherein calculating threshold values and their rates of change includes: decrementing a value of the exposure time; calculating a value of the modeled behavior at the measuring point; determining a value of the modeled behavior at a location offset from the measuring point in a first direction by a second value; determining a value of the modeled behavior at a location offset from the measuring point in a second direction, opposite to the first direction, by the second value; and calculating a rate of change of the modeled behavior corresponding to the exposure time.
Claim 61
Independent Claim
178 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of exposure time of a stepper; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining the exposure time corresponding to the optimum threshold value, wherein calculating threshold values and their rates of change includes: decrementing a value of the exposure time; calculating a value of the modeled behavior at the measuring point; determining a value of the modeled behavior at a location offset from the measuring point in a first direction by a second value; determining a value of the modeled behavior at a location offset from the measuring point in a second direction, opposite to the first direction, by the second value; and calculating a rate of change of the modeled behavior corresponding to the exposure time.
Claim 62
Dependent Claim
44 words
The method of claim 47 , wherein calculating the rate of change comprises: calculating a difference of the modeled behavior values ascertained during determining the values of the modeled behavior; and dividing the difference of the modeled behavior values by twice the second value.
Claim 63
Dependent Claim
35 words
The method of claim 44 , wherein selecting a measuring point, calculating modeled behavior values and their rates of change, selecting an optimum threshold value, and determining the exposure time are performed in a computer.
Claim 64
Independent Claim
93 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of on/off axis settings of a stepper with respect to a constant mask material edge; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining on/off axis settings corresponding to the optimum threshold value.
Claim 65
Independent Claim
93 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of on/off axis settings of a stepper with respect to a constant mask material edge; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining on/off axis settings corresponding to the optimum threshold value.
Claim 66
Dependent Claim
59 words
The method of claim 50 , wherein calculating modeled behavior values comprises: selecting a point on one side of the measuring point; calculating a value of the modeled behavior at each of the points; and calculating a slope through each of the points, wherein the slope is a function of the values of the modeled behavior at each point.
Claim 67
Independent Claim
150 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of on/off axis settings of a stepper with respect to a constant mask material edge; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining on/off axis settings corresponding to the optimum threshold value, wherein calculating modeled behavior values includes: selecting a point on one side of the measuring point; selecting a second point; calculating a value of the modeled behavior at each of the points; and calculating a slope through each of the points, wherein the slope is a function of the values of the modeled behavior at each point.
Claim 68
Independent Claim
150 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of on/off axis settings of a stepper with respect to a constant mask material edge; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining on/off axis settings corresponding to the optimum threshold value, wherein calculating modeled behavior values includes: selecting a point on one side of the measuring point; selecting a second point; calculating a value of the modeled behavior at each of the points; and calculating a slope through each of the points, wherein the slope is a function of the values of the modeled behavior at each point.
Claim 69
Independent Claim
181 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of on/off axis settings of a stepper; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining on/off axis settings corresponding to the optimum threshold value, wherein calculating threshold values and their rates of change includes: decrementing a value of the on/off axis setting; calculating a value of the modeled behavior at the measuring point; determining a value of the modeled behavior at a location offset from the measuring point in a first direction by a second value; determining a value of the modeled behavior at a location offset from the measuring point in a second direction, opposite to the first direction, by the second value; and calculating a rate of change of the modeled behavior corresponding to the on/off axis setting.
Claim 70
Independent Claim
181 words
A method for determining an optimum process point for fabricating a device feature of a critical dimension, comprising: selecting a measuring point on a computer representation of a wafer corresponding to the feature of the critical dimension; calculating modeled behavior values and their rates of change over a range of corresponding values of on/off axis settings of a stepper; selecting an optimum threshold value having a largest rate of change around the measuring point; and determining on/off axis settings corresponding to the optimum threshold value, wherein calculating threshold values and their rates of change includes: decrementing a value of the on/off axis setting; calculating a value of the modeled behavior at the measuring point; determining a value of the modeled behavior at a location offset from the measuring point in a first direction by a second value; determining a value of the modeled behavior at a location offset from the measuring point in a second direction, opposite to the first direction, by the second value; and calculating a rate of change of the modeled behavior corresponding to the on/off axis setting.
Claim 71
Dependent Claim
44 words
The method of claim 53 , wherein calculating the rate of change comprises: calculating a difference of the modeled behavior values ascertained during determining the values of the modeled behavior; and dividing the difference of the modeled behavior values by twice the second value.
Claim 72
Dependent Claim
35 words
The method of claim 50 , wherein selecting a measuring point, calculating modeled behavior values and their rates of change, selecting an optimum threshold value, and determining on/off axis settings are performed in a computer.
Claim 73
Dependent Claim
130 words
A computer program product comprising a memory having computer program logic recorded thereon for enabling a processor in a computer system to determine an optimum process point for fabricating a device feature of a critical dimension, the computer program logic comprising: a first calculating process enabling the processor to calculate a modeled behavior value associated with the device feature and a rate of change of the modeled behavior value over a range of corresponding values of an optical parameter of a stepper with respect to a constant mask material edge; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine the value of the optical parameter corresponding to the optimum threshold value.
Claim 74
Dependent Claim
130 words
A computer program product comprising a memory having computer program logic recorded thereon for enabling a processor in a computer system to determine an optimum process point for fabricating a device feature of a critical dimension, the computer program logic comprising: a first calculating process enabling the processor to calculate a modeled behavior value associated with the device feature and a rate of change of the modeled behavior value over a range of corresponding values of an optical parameter of a stepper with respect to a constant mask material edge; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine the value of the optical parameter corresponding to the optimum threshold value.
Claim 75
Dependent Claim
38 words
The computer program product of claim 56 , further comprising: a providing process enabling the processor to provide the optimum threshold value to a proximity effect correction process which modifies a mask pattern to compensate for proximity effects.
Claim 76
Dependent Claim
29 words
The computer program product of claim 56 , wherein the optical parameter is one of focus, numerical aperture, exposure time and on or off axis settings of the stepper.
Claim 77
Dependent Claim
102 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of an optical parameter of a stepper with respect to a constant mask material edge; a second calculating process enabling the processor to select an optimum threshold value having the largest rate of change; and a determining process enabling the processor to determine a value of the optical parameter corresponding to the optimum threshold value.
Claim 78
Dependent Claim
102 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of an optical parameter of a stepper with respect to a constant mask material edge; a second calculating process enabling the processor to select an optimum threshold value having the largest rate of change; and a determining process enabling the processor to determine a value of the optical parameter corresponding to the optimum threshold value.
Claim 79
Dependent Claim
37 words
The computer system of claim 59 , further comprising a providing process enabling the processor to provide the optimum threshold value to a proximity effect correction process which modifies a mask pattern to compensate for proximity effects.
Claim 80
Dependent Claim
25 words
The computer system of claim 59 , wherein the optical parameter is one of focus, numerical aperture, exposure time, and on or off axis setting.
Claim 81
Dependent Claim
114 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of an optical parameter of a stepper; a second calculating process enabling the processor to select an optimum threshold value having the largest rate of change; and a determining process enabling the processor to determine a value of the optical parameter corresponding to the optimum threshold value, wherein the rate of change of the modeled value indicates a process latitude of an edge of the device feature.
Claim 82
Dependent Claim
114 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of an optical parameter of a stepper; a second calculating process enabling the processor to select an optimum threshold value having the largest rate of change; and a determining process enabling the processor to determine a value of the optical parameter corresponding to the optimum threshold value, wherein the rate of change of the modeled value indicates a process latitude of an edge of the device feature.
Claim 83
Dependent Claim
102 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of an exposure time of a stepper with respect to a constant mask material edge; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine a value of an exposure time corresponding to the optimum threshold value.
Claim 84
Dependent Claim
102 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of an exposure time of a stepper with respect to a constant mask material edge; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine a value of an exposure time corresponding to the optimum threshold value.
Claim 85
Dependent Claim
37 words
The computer system of claim 63 , further comprising a providing process enabling the processor to provide the optimum threshold value to a proximity effect correction process which modifies a mask pattern to compensate for proximity effects.
Claim 86
Dependent Claim
115 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of an exposure time of a stepper; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine a value of an exposure time corresponding to the optimum threshold value, wherein the rate of change of the modeled behavior value indicates a process latitude of an edge of the device feature.
Claim 87
Dependent Claim
115 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of an exposure time of a stepper; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine a value of an exposure time corresponding to the optimum threshold value, wherein the rate of change of the modeled behavior value indicates a process latitude of an edge of the device feature.
Claim 88
Dependent Claim
99 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of focus of a stepper with respect to a constant mask material edge; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine a value of a focus corresponding to the optimum threshold value.
Claim 89
Dependent Claim
99 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of focus of a stepper with respect to a constant mask material edge; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine a value of a focus corresponding to the optimum threshold value.
Claim 90
Dependent Claim
37 words
The computer system of claim 66 , further comprising a providing process enabling the processor to provide the optimum threshold value to a proximity effect correction process which modifies a mask pattern to compensate for proximity effects.
Claim 91
Dependent Claim
111 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of focus of a stepper; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine a value of a focus corresponding to the optimum threshold value, wherein the rate of change of the modeled value indicates a process latitude of an edge of the device feature.
Claim 92
Dependent Claim
111 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of focus of a stepper; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine a value of a focus corresponding to the optimum threshold value, wherein the rate of change of the modeled value indicates a process latitude of an edge of the device feature.
Claim 93
Dependent Claim
102 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of a numerical aperture of a stepper with respect to a constant mask material edge; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine a value of a numerical aperture corresponding to the optimum threshold value.
Claim 94
Dependent Claim
102 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of a numerical aperture of a stepper with respect to a constant mask material edge; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine a value of a numerical aperture corresponding to the optimum threshold value.
Claim 95
Dependent Claim
37 words
The computer system of claim 69 , further comprising a providing process enabling the processor to provide the optimum threshold value to a proximity effect correction process which modifies a mask pattern to compensate for proximity effects.
Claim 96
Dependent Claim
114 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of a numerical aperture of a stepper; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine a value of a numerical aperture corresponding to the optimum threshold value, wherein the rate of change of the modeled value indicates a process latitude of an edge of the device feature.
Claim 97
Dependent Claim
114 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of a numerical aperture of a stepper; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine a value of a numerical aperture corresponding to the optimum threshold value, wherein the rate of change of the modeled value indicates a process latitude of an edge of the device feature.
Claim 98
Dependent Claim
108 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of an on or off axis setting of a stepper with respect to a constant mask material edge; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine a value of an on or off axis setting corresponding to the optimum threshold value.
Claim 99
Dependent Claim
108 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of an on or off axis setting of a stepper with respect to a constant mask material edge; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine a value of an on or off axis setting corresponding to the optimum threshold value.
Claim 100
Dependent Claim
37 words
The computer system of claim 72 , further comprising a providing process enabling the processor to provide the optimum threshold value to a proximity effect correction process which modifies a mask pattern to compensate for proximity effects.
Claim 101
Dependent Claim
120 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of an on or off axis setting of a stepper; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine a value of an on or off axis setting corresponding to the optimum threshold value, wherein the rate of change of the modeled value indicates a process latitude of an edge of the device feature.
Claim 102
Dependent Claim
120 words
A computer system, comprising: a processor; a memory operatively coupled to the processor; a first calculating process enabling the processor to calculate a modeled behavior value associated with a device feature and a rate of change of the modeled behavior value over a range of corresponding values of an on or off axis setting of a stepper; a second calculating process enabling the processor to select an optimum threshold value having a largest rate of change; and a determining process enabling the processor to determine a value of an on or off axis setting corresponding to the optimum threshold value, wherein the rate of change of the modeled value indicates a process latitude of an edge of the device feature.
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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) | 2006-02-10 | 2006-08-12 | 2007-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2010-02-10 | 2010-08-12 | 2011-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2014-02-10 | 2014-08-12 | 2015-02-11 | $7700.00 | Window Closed / Lapsed |