U.S. patent application number 12/012970 was filed with the patent office on 2008-06-26 for exposure mask, optical proximity correction device, optical proximity correction method, manufacturing method of semiconductor device, and optical proximity correction program.
Invention is credited to Hisashi Akiyama.
Application Number | 20080153009 12/012970 |
Document ID | / |
Family ID | 33526700 |
Filed Date | 2008-06-26 |
United States Patent
Application |
20080153009 |
Kind Code |
A1 |
Akiyama; Hisashi |
June 26, 2008 |
Exposure mask, optical proximity correction device, optical
proximity correction method, manufacturing method of semiconductor
device, and optical proximity correction program
Abstract
An optical proximity correction is provided that generates a
corrected pattern P0 corresponding to a state M0 where the focus is
in focus and the exposure dose is optimal, a corrected pattern P1
corresponding to a state M1 where the focus is in focus and the
exposure dose is at the lower limit, a corrected pattern P2
corresponding to a state M2 where the focus is in focus and the
exposure dose is at the upper limit, a corrected pattern P3
corresponding to a state M3 where the focus deviates to the lower
side and the exposure dose is optimal, and a corrected pattern P4
corresponding to a state M4 where the focus deviates to the upper
side and the exposure dose is optimal. By combining these corrected
patterns P0 through P4, a composed pattern P5 is generated that
reflects the scattering of the exposure dose and the deviation of
the focus.
Inventors: |
Akiyama; Hisashi; (Setagaya,
JP) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, P.L.C.
P.O. BOX 828
BLOOMFIELD HILLS
MI
48303
US
|
Family ID: |
33526700 |
Appl. No.: |
12/012970 |
Filed: |
February 6, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10846837 |
May 14, 2004 |
7353493 |
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12012970 |
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Current U.S.
Class: |
430/5 ;
430/313 |
Current CPC
Class: |
G03F 1/36 20130101 |
Class at
Publication: |
430/5 ;
430/313 |
International
Class: |
G03F 1/00 20060101
G03F001/00; G03F 7/26 20060101 G03F007/26 |
Foreign Application Data
Date |
Code |
Application Number |
May 15, 2003 |
JP |
2003-136914 |
Claims
1. An exposure mask, comprising: a mask pattern corrected by
simulation-based correction based on both: measured data with
proper focus; and exposure dose and measured data with at least one
of focus and exposure dose deviating.
2. A manufacturing method for a semiconductor device, comprising:
applying photoresist onto a semiconductor wafer; exposing the
photoresist through an exposure mask that is corrected by
simulation-based correction based on both measured data with proper
focus and exposure dose and measured data with at least one of
focus and exposure dose deviating; developing the exposed
photoresist; and providing the semiconductor wafer with one of ion
implantation and etching using the developed photoresist as a mask.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional application of U.S. Ser.
No. 10/846,837 filed May 14, 2004, claiming priority to Japanese
Patent Application No. 2003-136914 filed May 15, 2003, all of which
are hereby expressly incorporated by reference herein in their
entireties.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present invention relates to an exposure mask, an
optical proximity correction (OPC) device, an optical proximity
correction method, a manufacturing method for a semiconductor, and
an optical proximity correction program, and more particularly, it
is favorably applied to an optical proximity correction method
considering a photo margin.
[0004] 2. Description of the Related Art
[0005] In conventional optical proximity correction methods, for
example, as is shown in Japanese Unexamined Patent Application
Publication No. 2000-310851, for the sizing process of the
graphical data for an electron beam (EB) lithography device
providing an OPC part, there is a method for carrying out the
sizing process using the sizing values differing in the figures
with OPC and the figures without OPC and then combining both
figures that have undergone the sizing process, in order to prevent
the disappearance of the OPC part.
[0006] However, in conventional optical proximity correction
methods, a problem is encountered in that the influence of the
scattering of an exposure dose and the deviation of a focus has to
be corrected by hand as the influence of the scattering of the
exposure dose and the deviation of the focus are not considered
when making a simulation-based adjustment.
[0007] Here, the present invention is intended to provide an
exposure mask, an optical proximity correction device, an optical
proximity correction method, a manufacturing method for a
semiconductor, and an optical proximity correction program which
enable the correction of optical proximity effects while
considering the photo margin.
SUMMARY
[0008] In order to solve the above-mentioned issue, in an exposure
mask according to one aspect of the present invention, the pattern
of the mask is corrected by simulation-based correction based on
both measured data with proper focus and exposure dose and measured
data with at least one of focus and exposure dose deviating.
[0009] Thereby, while reflecting the scattering of the exposure
dose or the deviation of the focus, it becomes possible to carry
out optical proximity correction of the mask pattern. Therefore,
even in the case where the exposure dose or the focus deviates in
the exposure step, the optical proximity effect can be effectively
corrected, and it becomes possible to efficiently produce fine
patterns.
[0010] An optical proximity correction device according to another
aspect of the present invention includes a data input means for
inputting data of a pattern to be processed, a first corrected
pattern generating means for generating a first corrected pattern
by correcting the pattern to be processed based on a model adjusted
with reference to measured data with proper focus and exposure
dose, a second corrected pattern generating means for generating a
second corrected pattern by correcting the pattern to be processed
based on a model adjusted with reference to measured data with at
least one of focus and exposure dose deviating, and a composed
pattern generating means for generating a composed pattern by
combining the first corrected pattern and the second corrected
pattern.
[0011] According to this, while reflecting the scattering of the
exposure dose and the deviation of the focus, it becomes possible
to carry out optical proximity correction of the mask pattern, and
even in the case where the exposure dose or the focus deviates in
the exposure step, the optical proximity effect can be effectively
corrected.
[0012] An optical proximity correction device according to another
aspect of the present invention includes a data input means for
inputting data of a pattern to be processed, a first corrected
pattern generating means for adding a hammerhead, a serif and a
bias to each line-end region, corner region, and line-and-space
region of the pattern to be processed, based on a model adjusted
with reference to measured data with proper focus and exposure
dose, a second corrected pattern generating means for adding a
hammerhead, a serif and a bias to each line-end region, corner
region, and line-and-space region of the pattern to be processed,
based on a model adjusted with reference to measured data with at
least one of focus and exposure dose deviating, and a composed
pattern generating means for generating a composed pattern by
combining the first corrected pattern and the second corrected
pattern.
[0013] Thereby, it becomes possible to add a hammerhead, a serif
and a bias to each line-end region, corner region, and
line-and-space region of the pattern to be processed while
reflecting the scattering of the exposure dose and the deviation of
the focus, and the optical proximity effect can be effectively
corrected even in the case where the exposure dose or the focus
deviates in the exposure step.
[0014] Further, in the optical proximity correction device
according to another aspect of the present invention the measured
data with at least one of focus and exposure dose deviating is data
on a photo margin borderline.
[0015] Thereby, even in the case where a photo process varies
within a norm value, it becomes possible to efficiently generate a
mask pattern in which the optical proximity effect can be
effectively corrected.
[0016] Further, in the optical proximity correction device
according to another aspect of the present invention the composed
pattern generating means further includes a first dimensional
deviation calculating means for calculating a dimensional deviation
between the pattern to be processed and the first corrected pattern
as for at least part of edges, a second dimensional deviation
calculating means for calculating a dimensional deviation between
the pattern to be processed and the second corrected pattern as for
at least part of edges, and a weighted average calculating means
for calculating the weighted average of the dimensional deviations
each calculated by the first dimensional deviation calculating
means and the second dimensional deviation calculating means.
[0017] Thereby, while enabling the adjustment of the degree to
which the scattering of the exposure dose and the deviation of the
focus are reflected, it becomes possible to easily compose a
plurality of patterns reflecting the scattering of the exposure
dose and the deviation of the focus, and to efficiently generate an
optical proximity correction pattern reflecting the scattering of
the exposure dose and the deviation of the focus.
[0018] Further, in the optical proximity correction device
according to another aspect of the present invention a rule-based
correcting means for rule-based correcting of a border of a
composed pattern that is generated by the composed pattern
generating means.
[0019] Thereby, by combining a plurality of patterns reflecting the
scattering of the exposure dose and the deviation of the focus,
even in the case where in the vicinity of the border of the
composed pattern small steps have been created, it becomes possible
to easily remove these steps and to pass through a design rule
check or an optical rule check.
[0020] An optical proximity correction method according to another
aspect of the present invention includes:
[0021] inputting data of a pattern to be processed,
[0022] adjusting a model for optical proximity correction with
reference to measured data with proper focus and exposure dose,
[0023] generating a first corrected pattern by correcting the
pattern to be processed based on the model for optical proximity
correction adjusted with reference to the measured data with proper
focus and exposure dose,
[0024] adjusting a model for optical proximity correction with
reference to measured data with at least one of focus and exposure
dose deviating,
[0025] generating a second corrected pattern by correcting the
pattern to be processed based on the model for optical proximity
correction adjusted with reference to the measured data with at
least one of focus and exposure dose deviating,
[0026] generating a composed pattern by combining the first
corrected pattern and the second corrected pattern, and
[0027] correcting the border of the composed pattern on a rule
basis.
[0028] Thereby, it becomes possible to carry out optical proximity
correction of the mask pattern considering the photo margin, and
even in the case where the exposure dose or the focus deviates in
the exposure step, it is possible to effectively correct the
optical proximity effect.
[0029] An optical proximity correction method according to another
aspect of the present invention includes:
[0030] inputting data of a pattern to be processed;
[0031] adjusting a model for optical proximity correction with
reference to measured data with proper focus and exposure dose;
[0032] generating a first corrected pattern by adding a hammerhead,
a serif and a bias to each line-end region, corner region, and
line-and-space region of the pattern to be processed, based on the
model for optical proximity correction adjusted with reference to
the measured data with proper focus and exposure dose;
[0033] adjusting a model for optical proximity correction with
reference to measured data with at least one of focus and exposure
dose deviating;
[0034] generating a second corrected pattern by adding a
hammerhead, a serif and a bias to each line-end region, corner
region, and line-and-space region of the pattern to be processed,
based on the model for optical proximity correction adjusted with
reference to the measured data with at least one of focus and
exposure dose deviating;
[0035] generating a composed pattern by combining the first
corrected pattern and the second corrected pattern; and
[0036] correcting the border of the composed pattern on a rule
basis.
[0037] Thereby, it becomes possible to add a hammerhead, a serif
and a bias to each line-end region, corner region, and
line-and-space region of the pattern to be processed with
consideration to the photo margin, and thus, the optical proximity
effect can be effectively corrected even in the case where the
exposure dose or the focus deviates in the exposure step.
[0038] A manufacturing method for a semiconductor device according
to another aspect of the present invention includes:
[0039] applying photoresist onto a semiconductor wafer;
[0040] exposing the photoresist through an exposure mask that is
corrected by simulation-based correction based on both measured
data with proper focus and exposure dose and measured data with at
least one of focus and exposure dose deviating;
[0041] developing the exposed photoresist; and
[0042] providing the semiconductor wafer with ion implantation or
etching using the developed photoresist as a mask.
[0043] Thereby, it becomes possible to use the exposure mask
wherein the optical proximity effect has been corrected with
consideration to the photo margin for carrying out
photolithography, and even in the case where the exposure dose or
the focus deviates in the exposure step, fine patterns can be
formed with good precision.
[0044] An optical proximity correction program according to another
aspect of the present invention includes:
[0045] receiving data of a pattern to be processed,
[0046] adjusting a model for optical proximity correction with
reference to measured data with proper focus and exposure dose,
[0047] generating a first corrected pattern by correcting the
pattern to be processed based on the model for optical proximity
correction adjusted with reference to the measured data with proper
focus and exposure dose,
[0048] adjusting a model for optical proximity correction with
reference to measured data with at least one of focus and exposure
dose deviating,
[0049] generating a second corrected pattern by correcting the
pattern to be processed based on the model for optical proximity
correction adjusted with reference to the measured data with at
least one of focus and exposure dose deviating,
[0050] generating a composed pattern by combining the first
corrected pattern and the second corrected pattern, and
[0051] correcting the border of the composed pattern on a rule
basis, and
[0052] all of the above is processed by a computer.
[0053] Thereby, by processing the optical proximity correction
program with a computer, it becomes possible to carry out optical
proximity correction with consideration to the photo margin, and
even in the case where the exposure dose or the focus deviates in
the exposure step, it becomes possible to efficiently generate a
mask pattern that enables the optical proximity effect to be
effectively corrected.
[0054] An optical proximity correction program according to another
aspect of the present invention includes:
[0055] receiving data of a pattern to be processed;
[0056] adjusting a model for optical proximity correction with
reference to measured data with proper focus and exposure dose;
[0057] generating a first corrected pattern by adding a hammerhead,
a serif and a bias to each line-end region, corner region, and
line-and-space region of the pattern to be processed, based on the
model for optical proximity correction adjusted with reference to
the measured data with proper focus and exposure dose;
[0058] adjusting a model for optical proximity correction with
reference to measured data with at least one of focus and exposure
dose deviating;
[0059] generating a second corrected pattern by adding a
hammerhead, a serif and a bias to each line-end region, corner
region, and line-and-space region of the pattern to be processed,
based on the model for optical proximity correction adjusted with
reference to the measured data with at least one of focus and
exposure dose deviating;
[0060] generating a composed pattern by combining the first
corrected pattern and the second corrected pattern; and
[0061] correcting the border of the composed pattern on a rule
basis, and
[0062] all of the above is processed by a computer.
[0063] Thereby, by processing the optical proximity correction
program with a computer, it becomes possible to add a hammerhead, a
serif and a bias with consideration to the photo margin to each
line-end region, corner region, and line-and-space region of the
pattern to be processed, and it becomes possible to efficiently
generate a mask pattern that enables the optical proximity effect
to be effectively corrected even in the case where the exposure
dose or the focus deviates in the exposure step.
BRIEF DESCRIPTION OF THE DRAWINGS
[0064] FIG. 1 is a view showing an optical proximity correction
method according to an embodiment.
[0065] FIG. 2 is a view showing a photo margin according to an
embodiment.
[0066] FIG. 3 is a view showing an optical proximity correction
method according to an embodiment.
[0067] FIGS. 4A and B are views showing an optical proximity
correction method according to an embodiment.
[0068] FIG. 5 is a flowchart showing an optical proximity
correction method according to an embodiment.
DETAILED DESCRIPTION
[0069] Following is an explanation of an optical proximity
correction method according to an embodiment of the present
invention with reference to the drawings.
[0070] FIG. 1, FIG. 3 and FIG. 4 are plan views showing an optical
proximity correction method according to an embodiment of the
present invention, FIG. 2 is a view showing a photo margin in the
photolithography according to an embodiment of the present
invention.
[0071] In FIG. 1, for example, a U-shaped pattern is given as a
pattern P to be processed. Here, the pattern P to be processed can
be made up of parts to be processed, and as the parts to be
processed, for example, line-end regions, corner regions and
line-and-space regions can be given. The line-end regions
correspond to ends of the pattern P to be processed, the corner
regions correspond to the corner parts (including the inner and
outer corners) of the pattern P to be processed, and the
line-and-space regions correspond to the remaining regions with the
exemption of the line-end regions and the corner regions. Further,
isolated lines (patterns in the shape of a single line) can be
included in the line-and-space regions.
[0072] When the pattern P to be processed is given, through an
exposure mask onto which the pattern P to be processed is formed,
the photoresist is exposed with proper focus and exposure dose. The
exposed photoresist is developed, and a resist pattern is formed
with proper focus and exposure dose. The resist pattern with proper
focus and exposure dose is then checked using an SEM (scanning
electron microscope) or the like, and thereby measured data of the
resist pattern with proper focus and exposure dose is obtained.
After obtaining the measured data of the resist pattern with proper
focus and exposure dose, a model for optical proximity correction
is adjusted based on the measured data of the resist pattern with
proper focus and exposure dose. Based on the model for optical
proximity correction adjusted with reference to the measured data
with proper focus and exposure dose, a corrected pattern is
generated with the pattern P to be processed corrected on a
simulation basis.
[0073] Further, when the pattern P to be processed is given,
through an exposure mask onto which the pattern P to be processed
is formed, the photoresist is exposed under a condition with at
least one of focus and exposure dose deviating. The exposed
photoresist is developed, and a resist pattern is formed with at
least one of focus and exposure dose deviating. The resist pattern
with at least one of focus and exposure dose deviating is then
checked using an SEM (scanning electron microscope) or the like,
and thereby measured data of the resist pattern with at least one
of focus and exposure dose deviating is obtained. After obtaining
the measured data of the resist pattern with at least one of focus
and exposure dose deviating, a model for optical proximity
correction is adjusted based on the measured data of the resist
pattern with at least one of focus and exposure dose deviating.
Based on the model for optical proximity correction adjusted with
reference to the measured data with at least one of focus and
exposure dose deviating, a corrected pattern is generated with the
pattern P to be processed corrected on a simulation basis.
[0074] Here, the measured data on the borderline of the photo
margin can be used as the measured data with at least one of focus
and exposure dose deviating. That is to say, as shown in FIG. 2,
the photo margin is set to show the tolerances of the scattering of
the exposure dose and the deviation of the focus in the photo
process. As measured data on a borderline K of the photo margin the
following conditions (further referred to as states) can be used
for example:
[0075] an M1 state where the focus is in focus and the exposure
dose is at the lower limit,
[0076] an M2 state where the focus is in focus and the exposure
dose is at the upper limit,
[0077] an M3 state where the focus deviates to the lower side and
the exposure dose is optimal, and
[0078] an M4 state where the focus deviates to the upper side and
the exposure dose is optimal.
[0079] Further, as measured data with proper focus and exposure
dose, an M0 state where focus is in focus and the exposure dose is
optimal can be used.
[0080] Based on the optical proximity correction model
corresponding to the M0 state where the focus is in focus and the
exposure dose is optimal, a corrected pattern P0 corrected on a
simulation basis can be generated by adding hammerheads H1 and H2,
negative serifs NS1 and NS2, positive serifs PS1 and PS2, and
biases BS1 and BS2 to each line-end region, inner corner region,
outer corner region, and line-and-space region of the pattern P to
be processed, as shown in FIG. 1.
[0081] Further, based on the optical proximity correction model
corresponding to the M1 state where the focus is in focus and the
exposure dose is at the lower limit, a corrected pattern P1
corrected on a simulation basis can be generated by adding
hammerheads H11 and H12, negative serifs NS11 and NS12, positive
serifs PS11 and PS12, and biases BS11 and BS12 to each line-end
region, inner corner region, outer corner region, and
line-and-space region of the pattern P to be processed, as shown in
FIG. 1.
[0082] Further, based on the optical proximity correction model
corresponding to the M2 state where the focus is in focus and the
exposure dose is at the upper limit, a corrected pattern P2
corrected on a simulation basis can be generated by adding
hammerheads H21 and H22, negative serifs NS21 and NS22, positive
serifs PS21 and PS22, and biases BS21 and BS22 to each line-end
region, inner corner region, outer corner region, and
line-and-space region of the pattern P to be processed, as shown in
FIG. 1.
[0083] Further, based on the optical proximity correction model
corresponding to the M3 state where the focus deviates to the lower
side and the exposure dose is optimal, a corrected pattern P3
corrected on a simulation basis can be generated by adding
hammerheads H31 and H32, negative serifs NS31 and NS32, positive
serifs PS31 and PS32, and biases BS31 and BS32 to each line-end
region, inner corner region, outer corner region, and
line-and-space region of the pattern P to be processed, as shown in
FIG. 1.
[0084] Further, based on the optical proximity correction model
corresponding to the M4 state where the focus deviates to the upper
side and the exposure dose is optimal, a corrected pattern P4
corrected on a simulation basis can be generated by adding
hammerheads H41 and H42, negative serifs NS41 and NS42, positive
serifs PS41 and PS42, and biases BS41 and BS42 to each line-end
region, inner corner region, outer corner region, and
line-and-space region of the pattern P to be processed, as shown in
FIG. 1.
[0085] Accordingly, the pattern P0 corresponding to the M0 state
where the focus is in focus and the exposure dose is optimal, the
pattern P1 corresponding to the M1 state where the focus is in
focus and the exposure dose is at the lower limit, the pattern P2
corresponding to the M2 state where the focus is in focus and the
exposure dose is at the upper limit, the pattern P3 corresponding
to the M3 state where the focus deviates to the lower side and the
exposure dose is optimal, and the pattern P4 corresponding to the
M4 state where the focus deviates to the upper side and the
exposure dose is optimal are generated. Subsequently, a composed
pattern P5 is generated by combining these corrected patterns P0
through P4. More specifically, hammerheads H51 and H52, negative
serifs NS51 and NS52, positive serifs PS51 and PS52 and biases BS51
and BS52 are added to each line-end region, inner corner region,
outer corner region, and line-and-space region of the pattern P to
be processed, as shown in FIG. 3.
[0086] Thereby, it becomes possible to add the hammerheads H51 and
H52, the negative serifs NS51 and NS52, the positive serifs PS51
and PS52, and the biases BS51 and BS52 to each line-end region,
corner region, and line-and-space region of the pattern P to be
processed, while reflecting the scattering of the exposure dose or
the deviation of the focus, and the optical proximity effect can be
effectively corrected even in the case where the exposure dose or
the focus deviates in an exposure step.
[0087] When generating the composed pattern P5 from the corrected
patterns P0 through P4, the dimensional deviations between the
pattern P to be processed and each corrected pattern P0 to P4 are
calculated as for at least part of edges. The composed pattern P5
can also be generated by multiplying the dimensional deviations
between the pattern P to be processed and each corrected pattern P0
to P4 by weights W0 to W4, and calculating the weighted average of
each edge of the patterns P0 to P4.
[0088] Thereby, while enabling the adjustment of the degree to
which the scattering of the exposure dose and the deviation of the
focus are reflected, it becomes possible to easily combine the
corrected patterns P0 to P4 reflecting the scattering of the
exposure dose and the deviation of the focus, and to efficiently
generate the composed pattern P5 reflecting the scattering of the
exposure dose and the deviation of the focus.
[0089] Here, when generating the composed pattern P5 from the
corrected patterns P0 through P4, as shown in FIG. 4(a), in the
vicinity of the border of the composed pattern P5 steps D are
created. As shown in FIG. 4(b), by providing rule-based correcting
for the vicinity of the border of the composed pattern P5 on a rule
basis, the steps D created in the vicinity of the border of the
composed pattern P5 can be easily removed.
[0090] Thereby, by combining of the corrected patterns P0 through
P4 reflecting the scattering of the exposure dose and the deviation
of the focus, even in the case where the steps D have been created
in the vicinity of the border of the composed pattern P5, it
becomes possible to easily remove these steps D, and to pass
through a design rule check or an optical rule check.
[0091] Here, simulation-based correction uses a simulator wherein
the phenomena that accompany the exposure process are modeled.
Simulation-based correction is disclosed, for example, in a paper
by Satomi Shioiri et al, titled: Fast optical proximity correction:
analytical method, in: Optical/Laser Microlithography VIII, Vol.
2440, SPIE Symposium on Microlithography 1995, p. 261-269.
[0092] Here, rule-based correction is a method to carry out optical
proximity correction based on previously determined correction
rules. Rule-based correction is disclosed, for example, in a paper
by Oberdan W. Otto et al, titled: Automated optical proximity
correction--a rule-based approach, in: Optical/Laser
Microlithography VII, Vol. 2197, SPIE Symposium on Microlithography
1994, p. 278-293, and in a paper by Richard C. Henderson et al,
titled: correcting for proximity effect widens process latitude, p.
361-370.
[0093] Further, in the above-mentioned embodiment, a method is
explained, that uses, as the measured data on the borderline K of
the photo margin, the M1 state where the focus is in focus and the
exposure dose is at the lower limit, the M2 state where the focus
is in focus and the exposure dose is at the upper limit, the M3
state where the focus deviates to the lower side and the exposure
dose is optimal, and the M4 state where the focus deviates to the
upper side and the exposure dose is optimal. However, it is not
limited to the above, that is, it is not necessary to include all
of these states M1 to M4, and alternatively, states M1 to M4
different from these can be used to generate the composed
pattern.
[0094] FIG. 5 is a flowchart showing an optical proximity
correction method according to an embodiment of the present
invention.
[0095] In FIG. 5, when a pattern to be processed for optical
proximity correction is inputted, a resist pattern can be obtained
with proper focus and exposure dose, by exposing a photoresist
under a condition with proper focus and exposure dose through an
exposure mask, onto which the pattern to be processed is formed.
And, based on the measured data of the resist pattern with proper
focus and exposure dose a model for optical proximity correction is
adjusted (Step 1).
[0096] Further, when the pattern to be processed for optical
proximity correction is inputted, a resist pattern with at least
one of focus and exposure dose deviating is obtained by exposing
the photoresist under a condition where focus and exposure dose are
set on the borderline K of the photo margin of FIG. 2, through an
exposure mask, onto which the pattern to be processed is formed.
And, based on the measured data of the resist pattern with at least
one of focus and exposure dose deviating a model for optical
proximity correction is adjusted (Step 2).
[0097] Further, when the model for optical proximity correction
that was adjusted under the condition with proper focus and
exposure dose, and the model for optical proximity correction that
was composed under the condition with at least one of focus and
exposure dose deviating are obtained, an OPC pattern is added to
the pattern to be processed according to each optical proximity
correction model (Step 3).
[0098] Next, when the corrected pattern is generated to which each
OPC pattern has been added, the dimensional deviation between the
pattern to be processed and the corrected pattern is calculated as
for at least part of edges. The dimensional deviation between the
pattern to be processed and the corrected pattern is then
multiplied by a weight, and a composed pattern is generated by
calculating the weighted average of the edges of the patterns (Step
4).
[0099] After the composed pattern is generated, by providing
rule-based correction for the vicinity of the border of the
composed pattern, steps that have been created in the vicinity of
the border of the composed pattern are removed (Step 5).
* * * * *