U.S. patent application number 16/263427 was filed with the patent office on 2020-03-12 for position measuring method, position measuring apparatus, and semiconductor device manufacturing method.
This patent application is currently assigned to Toshiba Memory Corporation. The applicant listed for this patent is Toshiba Memory Corporation. Invention is credited to Yosuke Okamoto, Miki Toshima, Osamu Yamane.
Application Number | 20200081357 16/263427 |
Document ID | / |
Family ID | 69719134 |
Filed Date | 2020-03-12 |
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United States Patent
Application |
20200081357 |
Kind Code |
A1 |
Toshima; Miki ; et
al. |
March 12, 2020 |
POSITION MEASURING METHOD, POSITION MEASURING APPARATUS, AND
SEMICONDUCTOR DEVICE MANUFACTURING METHOD
Abstract
According to one embodiment, in a position measuring method,
alignment measurement in a light exposure process is executed by
irradiating a first mark with light having a wavelength of
.lamda.1, with respect to a processing object that includes a first
layer and a second layer stacked above a substrate and a resist
applied on the second layer. The first mark is provided in the
first layer and includes a plurality of segments arranged at a
pitch smaller than a resolution limit given by light having the
wavelength of .lamda.1. Then, overlay measurement is executed by
irradiating the first mark and a second mark with light having a
wavelength of .lamda.2 shorter than the wavelength of .lamda.1. The
second mark has been formed by performing a light exposure and
development process to the resist, and includes a plurality of
segments arranged at the pitch.
Inventors: |
Toshima; Miki; (Yokohama,
JP) ; Yamane; Osamu; (Yokohama, JP) ; Okamoto;
Yosuke; (Sagamihara, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Toshiba Memory Corporation |
Tokyo |
|
JP |
|
|
Assignee: |
Toshiba Memory Corporation
Tokyo
JP
|
Family ID: |
69719134 |
Appl. No.: |
16/263427 |
Filed: |
January 31, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L 2223/5446 20130101;
G03F 7/70633 20130101; G03F 9/7088 20130101; G03F 9/708 20130101;
H01L 21/67259 20130101; G03F 9/7076 20130101; H01L 21/682 20130101;
H01L 2223/5442 20130101; H01L 2223/54426 20130101; H01L 23/544
20130101; G03F 9/7065 20130101; G03F 9/7084 20130101 |
International
Class: |
G03F 9/00 20060101
G03F009/00; G03F 7/20 20060101 G03F007/20; H01L 23/544 20060101
H01L023/544; H01L 21/67 20060101 H01L021/67; H01L 21/68 20060101
H01L021/68 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 7, 2018 |
JP |
2018-168209 |
Claims
1. A position measuring method comprising: executing alignment
measurement in a light exposure process by irradiating a first mark
with light having a wavelength of .lamda.1, with respect to a
processing object that includes a first layer and a second layer
stacked above a substrate and a resist applied on the second layer,
in which the first mark is provided in the first layer and includes
a plurality of segments arranged at a pitch smaller than a
resolution limit given by light having the wavelength of .lamda.1;
and executing overlay measurement by irradiating the first mark and
a second mark with light having a wavelength of .lamda.2 shorter
than the wavelength of .lamda.1, the second mark having been formed
by performing a light exposure and development process to the
resist, and including a plurality of segments arranged at the
pitch.
2. The position measuring method according to claim 1, wherein the
first mark has a structure in which line patterns are arranged in
quadrangular shapes that are doubly arranged, and the second mark
has a structure in which line patterns are arranged in a
quadrangular shape.
3. The position measuring method according to claim 2, wherein the
first mark includes an inner pattern including a first component, a
second component, a third component, and a fourth component
arranged in a quadrangular shape, the first component and the
second component extending in a first direction and being arranged
in parallel with each other, the third component and the fourth
component extending in a second direction perpendicular to the
first direction and being arranged in parallel with each other, and
an outer pattern including a fifth component, a sixth component, a
seventh component, and an eighth component arranged in a
quadrangular shape outside the inner pattern, the fifth component
and the sixth component extending in the first direction and being
arranged in parallel with each other, the seventh component and the
eighth component extending in the second direction and being
arranged in parallel with each other, and the second mark includes
a ninth component, a tenth component, an eleventh component, and a
twelfth component arranged in a quadrangular shape, the ninth
component and the tenth component extending in the first direction
and being arranged in parallel with each other, the eleventh
component and the twelfth component extending in the second
direction and being arranged in parallel with each other.
4. The position measuring method according to claim 3, wherein each
of the components includes a plurality of segments arranged at the
pitch in an extending direction of this component.
5. The position measuring method according to claim 1, wherein the
executing alignment measurement includes obtaining a first image of
the first mark by irradiation with light having the wavelength of
.lamda.1, and grasping an inverse autocorrelation at positions
across the first mark using the first image and a reversed first
image formed by reversing the first image, and calculating a
position highest in this inverse autocorrelation as a center
position, and the executing overlay measurement includes obtaining
a second image of the first mark and the second mark by irradiation
with light having the wavelength of .lamda.2, calculating a first
rotational center position by using intensity profiles of the first
mark same as each other in the second image and a rotated second
image formed by rotating the second image by 180.degree.,
calculating a second rotational center position by using intensity
profiles of the second mark same as each other in the second image
and the rotated second image, and calculating an overlay deviation
amount from the first rotational center position and the second
rotational center position.
6. The position measuring method according to claim 3, wherein the
executing alignment measurement includes obtaining a first image of
the first mark by irradiation with light having the wavelength of
.lamda.1, grasping an inverse autocorrelation at first positions
across the first component, the second component, the fifth
component, and the sixth component using the first image, and
calculating a position highest in this inverse autocorrelation as a
center position in the second direction, and grasping the inverse
autocorrelation at second positions across the third component, the
fourth component, the seventh component, and the eighth component
using the first image, and calculating a position highest in this
inverse autocorrelation as a center position in the first
direction, and the executing overlay measurement includes obtaining
a second image of the first mark and the second mark by irradiation
with light having the wavelength of .lamda.2, calculating a
rotational center position of the first mark in the first direction
from a correlation between an intensity profile of some of segments
forming the first component of the first mark in the second image,
and an intensity profile of some of segments forming the second
component of the first mark in a rotated second image formed by
rotating the second image by 180.degree., calculating a rotational
center position of the second mark in the first direction from a
correlation between an intensity profile of some of segments
forming the ninth component of the second mark in the second image,
and an intensity profile of some of segments forming the tenth
component of the second mark in the rotated second image,
calculating an overlay deviation amount in the first direction from
the rotational center positions of the first mark and the second
mark in the first direction, calculating a rotational center
position of the first mark in the second direction from a
correlation between an intensity profile of some of segments
forming the third component of the first mark in the second image,
and an intensity profile of some of segments forming the fourth
component of the first mark in the rotated second image,
calculating a rotational center position of the second mark in the
second direction from a correlation between an intensity profile of
some of segments forming the eleventh component of the second mark
in the second image, and an intensity profile of some of segments
forming the twelfth component of the second mark in the rotated
second image, and calculating an overlay deviation amount in the
second direction from the rotational center positions of the first
mark and the second mark in the second direction.
7. The position measuring method according to claim 6, wherein each
of the first component, the second component, the third component,
the fourth component, the ninth component, the tenth component, the
eleventh component, and the twelfth component includes n-number of
segments ("n" is an integer of 2 or more), the calculating the
rotational center position of the first mark in the first direction
includes obtaining a first intensity profile across a first region
and a second intensity profile across a second region, the first
region including i-th to j-th segments (each of "i" and "j" is an
integer of 1 or more and "n" or less, and "i<j" is satisfied),
counted from a first end in the first direction, of the first
component of the first mark, the second region including k-th to
m-th segments (each of "k" and "m" is an integer of 1 or more and
"n" or less, and "k<m" is satisfied), counted from the first end
in the first direction, of the second component of the first mark,
and grasping a correlation, with respect to the first intensity
profile, of the second intensity profile in the second image
rotated by 180.degree., the calculating the rotational center
position of the second mark in the first direction includes
obtaining a third intensity profile across a third region and a
fourth intensity profile across a fourth region, the third region
including i-th to j-th segments, counted from the first end in the
first direction, of the ninth component of the second mark, the
fourth region including k-th to m-th segments, counted from the
first end in the first direction, of the tenth component of the
second mark, and grasping a correlation, with respect to the third
intensity profile, of the fourth intensity profile in the second
image rotated by 180.degree., the calculating the rotational center
position of the first mark in the second direction includes
obtaining a fifth intensity profile across a fifth region and a
sixth intensity profile across a sixth region, the fifth region
including i-th to j-th segments, counted from a second end in the
second direction, of the third component of the first mark, the
sixth region including k-th to m-th segments, counted from the
second end in the second direction, of the fourth component of the
first mark, and grasping a correlation, with respect to the fifth
intensity profile, of the sixth intensity profile in the second
image rotated by 180.degree., and the calculating the rotational
center position of the second mark in the second direction includes
obtaining a seventh intensity profile across a seventh region and
an eighth intensity profile across an eighth region, the seventh
region including i-th to j-th segments, counted from the second end
in the second direction, of the eleventh component of the second
mark, the eighth region including k-th to m-th segments, counted
from the second end in the second direction, of the twelfth
component of the second mark, and grasping a correlation, with
respect to the seventh intensity profile, of the eighth intensity
profile in the second image rotated by 180.degree..
8. A position measuring apparatus performing position measurement
by irradiating, with light, a region in which a first mark and a
second mark are arranged with positional relationship corresponding
to each other, wherein the first mark and the second mark are
formed in layers different from each other in a measurement object,
and each of the first mark and the second mark includes two first
direction components that extend in a first direction and are
arranged in parallel with each other, and two second direction
components that extend in a second direction perpendicular to the
first direction and are arranged in parallel with each other, such
that the two first direction components face each other in the
second direction while the two second direction components face
each other in the first direction, each of the first direction
components has a configuration in which n-number of segments ("n"
is an integer of 2 or more) are arranged substantially at regular
intervals in the first direction, and each of the second direction
components has a configuration in which n-number of segments are
arranged substantially at regular intervals in the second
direction, the apparatus comprising: a controller configured to
obtain an image of a region including the first mark and the second
mark, and calculate an overlay deviation amount between the first
mark and the second mark in the image, wherein the controller is
configured to calculate an overlay deviation amount in the first
direction by performing a first process to each of the first mark
and the second mark, the first process including obtaining a first
intensity profile across a region including i-th to j-th segments
(each of "i" and "j" is an integer of 1 or more and "n" or less,
and "i<j" is satisfied), counted from a first end in the first
direction, of one first direction component of the two first
direction components, and a second intensity profile across a
region including k-th to m-th segments (each of "k" and "m" is an
integer of 1 or more and "n" or less, and "k<m", "i.noteq.k",
and "j.noteq.m" are satisfied), counted from the first end in the
first direction, of the other first direction component of the two
first direction components, and calculating a rotational center
position of a mark from a correlation, with respect to the first
intensity profile, of the second intensity profile in the image
rotated by 180.degree., and calculate an overlay deviation amount
in the second direction by performing a second process to each of
the first mark and the second mark, the second process including
obtaining a third intensity profile across a region including i-th
to j-th segments, counted from a second end in the second
direction, of one second direction component of the two second
direction components, and a fourth intensity profile across a
region including k-th to m-th segments, counted from the second end
in the second direction, of the other second direction component of
the two second direction components, and calculating a rotational
center position of a mark from a correlation, with respect to the
third intensity profile, of the fourth intensity profile in the
image rotated by 180.degree..
9. The position measuring apparatus according to claim 8, wherein,
in each of the first mark and the second mark, the two first
direction components and the two second direction components have
sizes substantially same as each other.
10. The position measuring apparatus according to claim 8, wherein
"i.gtoreq.2", "j.ltoreq.n-1", "k.gtoreq.2", and "m.ltoreq.n-1" are
satisfied.
11. The position measuring apparatus according to claim 8, wherein
"i+m=j+k=n+1" is satisfied.
12. The position measuring apparatus according to claim 8, wherein
the i-th to j-th segments and the k-th to m-th segments partly
include a segment present at a position same as each other counted
from the first end in the first direction in the calculating the
overlay deviation amount in the first direction, and partly include
a segment present at a position same as each other counted from the
second end in the second direction in the calculating the overlay
deviation amount in the second direction.
13. A semiconductor device manufacturing method comprising:
preparing a light exposure object by forming, on a first layer
provided with a first mark, a second layer and applying a resist
onto the second layer, the first mark including a plurality of
segments arranged at a pitch smaller than a resolution limit given
by light having a wavelength of .lamda.1; executing alignment
measurement by irradiating the first mark provided in the first
layer of the light exposure object with light having the wavelength
of .lamda.1; executing a light exposure process to the resist on a
basis of a result of the alignment measurement; forming a resist
pattern that includes a second mark including a plurality of
segments arranged at the pitch by executing a development process
to the resist subjected to the light exposure process; and
executing overlay measurement by irradiating the first mark and the
second mark with light having a wavelength of .lamda.2 shorter than
the wavelength of .lamda.1.
14. The semiconductor device manufacturing method according to
claim 13, wherein the first mark has a structure in which line
patterns are arranged in quadrangular shapes that are doubly
arranged, and the second mark has a structure in which line
patterns are arranged in a quadrangular shape.
15. The semiconductor device manufacturing method according to
claim 14, wherein the first mark includes an inner pattern
including a first component, a second component, a third component,
and a fourth component arranged in a quadrangular shape, the first
component and the second component extending in a first direction
and being arranged in parallel with each other, the third component
and the fourth component extending in a second direction
perpendicular to the first direction and being arranged in parallel
with each other, and an outer pattern including a fifth component,
a sixth component, a seventh component, and an eighth component
arranged in a quadrangular shape outside the inner pattern, the
fifth component and the sixth component extending in the first
direction and being arranged in parallel with each other, the
seventh component and the eighth component extending in the second
direction and being arranged in parallel with each other, and the
second mark includes a ninth component, a tenth component, an
eleventh component, and a twelfth component arranged in a
quadrangular shape, the ninth component and the tenth component
extending in the first direction and being arranged in parallel
with each other, the eleventh component and the twelfth component
extending in the second direction and being arranged in parallel
with each other.
16. The semiconductor device manufacturing method according to
claim 15, wherein each of the components includes a plurality of
segments arranged at the pitch in an extending direction of this
component.
17. The semiconductor device manufacturing method according to
claim 13, wherein the executing alignment measurement includes
obtaining a first image of the first mark by irradiation with light
having the wavelength of .lamda.1, and grasping an inverse
autocorrelation at positions across the first mark using the first
image and a reversed first image formed by reversing the first
image, and calculating a position highest in this inverse
autocorrelation as a center position, and the executing overlay
measurement includes obtaining a second image of the first mark and
the second mark by irradiation with light having the wavelength of
.lamda.2, calculating a first rotational center position by using
intensity profiles of the first mark same as each other in the
second image and a rotated second image formed by rotating the
second image by 180.degree., calculating a second rotational center
position by using intensity profiles of the second mark same as
each other in the second image and the rotated second image, and
calculating an overlay deviation amount from the first rotational
center position and the second rotational center position.
18. The semiconductor device manufacturing method according to
claim 15, wherein the executing alignment measurement includes
obtaining a first image of the first mark by irradiation with light
having the wavelength of .lamda.1, grasping an inverse
autocorrelation at first positions across the first component, the
second component, the fifth component, and the sixth component
using the first image, and calculating a position highest in this
inverse autocorrelation as a center position in the second
direction, and grasping the inverse autocorrelation at second
positions across the third component, the fourth component, the
seventh component, and the eighth component using the first image,
and calculating a position highest in this inverse autocorrelation
as a center position in the first direction, and the executing
overlay measurement includes obtaining a second image of the first
mark and the second mark by irradiation with light having the
wavelength of .lamda.2, calculating a rotational center position of
the first mark in the first direction from a correlation between an
intensity profile of some of segments forming the first component
of the first mark in the second image, and an intensity profile of
some of segments forming the second component of the first mark in
a rotated second image formed by rotating the second image by
180.degree., calculating a rotational center position of the second
mark in the first direction from a correlation between an intensity
profile of some of segments forming the ninth component of the
second mark in the second image, and an intensity profile of some
of segments forming the tenth component of the second mark in the
rotated second image, calculating an overlay deviation amount in
the first direction from the rotational center positions of the
first mark and the second mark in the first direction, calculating
a rotational center position of the first mark in the second
direction from a correlation between an intensity profile of some
of segments forming the third component of the first mark in the
second image, and an intensity profile of some of segments forming
the fourth component of the first mark in the rotated second image,
calculating a rotational center position of the second mark in the
second direction from a correlation between an intensity profile of
some of segments forming the eleventh component of the second mark
in the second image, and an intensity profile of some of segments
forming the twelfth component of the second mark in the rotated
second image, and calculating an overlay deviation amount in the
second direction from the rotational center positions of the first
mark and the second mark in the second direction.
19. The semiconductor device manufacturing method according to
claim 18, wherein each of the first component, the second
component, the third component, the fourth component, the ninth
component, the tenth component, the eleventh component, and the
twelfth component includes n-number of segments ("n" is an integer
of 2 or more), the calculating the rotational center position of
the first mark in the first direction includes obtaining a first
intensity profile across a first region and a second intensity
profile across a second region, the first region including i-th to
j-th segments (each of "i" and "j" is an integer of 1 or more and
"n" or less, and "i<j" is satisfied), counted from a first end
in the first direction, of the first component of the first mark,
the second region including k-th to m-th segments (each of "k" and
"m" is an integer of 1 or more and "n" or less, and "k<m" is
satisfied), counted from the first end in the first direction, of
the second component of the first mark, and grasping a correlation,
with respect to the first intensity profile, of the second
intensity profile in the second image rotated by 180.degree., the
calculating the rotational center position of the second mark in
the first direction includes obtaining a third intensity profile
across a third region and a fourth intensity profile across a
fourth region, the third region including i-th to j-th segments,
counted from the first end in the first direction, of the ninth
component of the second mark, the fourth region including k-th to
m-th segments, counted from the first end in the first direction,
of the tenth component of the second mark, and grasping a
correlation, with respect to the third intensity profile, of the
fourth intensity profile in the second image rotated by
180.degree., the calculating the rotational center position of the
first mark in the second direction includes obtaining a fifth
intensity profile across a fifth region and a sixth intensity
profile across a sixth region, the fifth region including i-th to
j-th segments, counted from a second end in the second direction,
of the third component of the first mark, the sixth region
including k-th to m-th segments, counted from the second end in the
second direction, of the fourth component of the first mark, and
grasping a correlation, with respect to the fifth intensity
profile, of the sixth intensity profile in the second image rotated
by 180.degree., and the calculating the rotational center position
of the second mark in the second direction includes obtaining a
seventh intensity profile across a seventh region and an eighth
intensity profile across an eighth region, the seventh region
including i-th to j-th segments, counted from the second end in the
second direction, of the eleventh component of the second mark, the
eighth region including k-th to m-th segments, counted from the
second end in the second direction, of the twelfth component of the
second mark, and grasping a correlation, with respect to the
seventh intensity profile, of the eighth intensity profile in the
second image rotated by 180.degree..
20. The semiconductor device manufacturing method according to
claim 13, further comprising: determining whether an overlay
deviation amount between the first mark and the second mark
obtained as a result of the overlay measurement falls within a
permissible range; peeling off the resist pattern when the overlay
deviation amount does not fall within the permissible range; and
applying a new resist onto the second layer, wherein to the light
exposure object with the new resist applied thereon, processes of
from the executing alignment measurement to the executing overlay
measurement are executed.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon and claims the benefit of
priority from Japanese Patent Application No. 2018-168209, filed on
Sep. 7, 2018; the entire contents of which are incorporated herein
by reference.
FIELD
[0002] An embodiment described herein relates generally to a
position measuring method, a position measuring apparatus, and a
semiconductor device manufacturing method.
BACKGROUND
[0003] In a process of manufacturing semiconductor devices, an
alignment mark is used for positioning a mask in a light exposure
apparatus, and an overlay mark is used for determining an overlay
deviation amount between patterns of layers stacked in a vertical
direction. The alignment mark and the overlay mark are arranged
together with other types of marks on dicing lines of a
substrate.
[0004] In semiconductor memory devices, it is desired that the area
of a memory cell region for arranging memory elements should be set
as large as possible to increase the storage capacity. One of the
methods for increasing the area of the memory cell region is to
reduce the area of dicing lines. However, since various types of
marks used for manufacturing semiconductor devices are arranged on
the dicing lines, it is difficult to reduce the area of the dicing
lines.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIGS. 1A and 1B are diagrams schematically illustrating a
configuration example of a substrate provided with marks according
to an embodiment;
[0006] FIGS. 2A and 2B are plan views schematically illustrating a
configuration example of marks according to the embodiment;
[0007] FIG. 3 is a sectional view schematically illustrating a
configuration example of marks according to the embodiment;
[0008] FIG. 4 is a flowchart illustrating an example of the
sequence of a semiconductor device manufacturing method including a
position measuring method according to the embodiment;
[0009] FIG. 5 is a diagram illustrating an image of a first mark in
alignment measurement;
[0010] FIG. 6 is a flowchart illustrating an example of an
alignment measuring process using first marks;
[0011] FIG. 7 is a diagram illustrating an example of X-direction
profiles in the alignment measuring process;
[0012] FIGS. 8A and 8B are diagrams illustrating an example of a
first mark and a second mark;
[0013] FIGS. 9A and 9B are a flowchart illustrating an example of
an overlay measuring process using first marks and second
marks;
[0014] FIG. 10 is a diagram illustrating an example of X-direction
profiles in the overlay measuring process;
[0015] FIGS. 11A and 11B are plan views illustrating a
configuration example of marks that can be used in diffraction
light measurement according to the embodiment; and
[0016] FIG. 12 is diagram illustrating a hardware configuration
example of a controller for each of a light exposure apparatus and
a position measuring apparatus.
DETAILED DESCRIPTION
[0017] In general, according to one embodiment, in a position
measuring method, alignment measurement in a light exposure process
is executed by irradiating a first mark with light having a
wavelength of .lamda.1, with respect to a processing object that
includes a first layer and a second layer stacked above a substrate
and a resist applied on the second layer. The first mark is
provided in the first layer and includes a plurality of segments
arranged at a pitch smaller than a resolution limit given by light
having the wavelength of .lamda.1. Then, overlay measurement is
executed by irradiating the first mark and a second mark with light
having a wavelength of .lamda.2 shorter than the wavelength of
.lamda.1. The second mark has been formed by performing a light
exposure and development process to the resist, and includes a
plurality of segments arranged at the pitch.
[0018] An exemplary embodiment of a position measuring method, a
position measuring apparatus, and a semiconductor device
manufacturing method will be explained below in detail with
reference to the accompanying drawings. The present invention is
not limited to the following embodiment.
[0019] FIGS. 1A and 1B are diagrams schematically illustrating a
configuration example of a substrate provided with marks according
to an embodiment. Here, FIG. 1A is a plan view, and FIG. 1B is a
sectional view taken along a line A-A of FIG. 1A. In FIG. 1A, the
upper half illustrates a plan view of a state before an upper layer
and a resist pattern are arranged, and the lower half illustrates a
plan view of a state where the upper layer and the resist pattern
are arranged on a lower layer. FIGS. 2A and 2B are plan views
schematically illustrating a configuration example of marks
according to the embodiment. Here, FIG. 2A is a view illustrating a
configuration example of a first mark, and FIG. 2B is a view
illustrating a configuration example of a second mark. FIG. 3 is a
sectional view schematically illustrating a configuration example
of marks according to the embodiment, which is taken along a line
B-B of FIG. 2B.
[0020] A substrate 100, such as a semiconductor substrate, is
provided with a rectangular pattern arrangement region 101 for
arranging patterns including a device pattern, and a frame-like
mark arrangement region 102 present around the pattern arrangement
region 101. The mark arrangement region 102 is a region to serve as
dicing lines. In the mark arrangement region 102, various types of
marks are arranged, which include marks 210 and 310 to be used for
alignment measurement and overlay measurement. In this embodiment,
marks to be used for the alignment measurement and the overlay
measurement are made in common. Specifically, the same set of marks
210 and 310 can be used to perform the alignment measurement and
the overlay measurement. As illustrated in FIG. 1A, for example,
this set of marks 210 and 310 is provided at a plurality of places
of the mark arrangement region 102 on the substrate 100, and the
alignment measurement and the overlay measurement can be performed
with high accuracy by using the respective sets of marks 210 and
310 at the plurality of places.
[0021] On the substrate 100, a first layer 111 serving as a lower
layer is arranged. The first layer 111 includes a patterned
conductive film or the like, for example. Further, the first layer
111 may include an interlayer insulating film arranged on the
conductive film. The first marks 210 are arranged in that part of
the first layer 111, which is present on the mark arrangement
region 102. As illustrated in FIGS. 1A and 2A, each of the first
marks 210 is a bar-in-bar mark having a structure in which line
patterns are arranged in quadrangular shapes that are doubly
arranged. Hereinafter, the quadrangular shape pattern on the inner
side will be referred to as "inner pattern 220", and the
quadrangular shape pattern on the outer side will be referred to as
"outer pattern 230". The inner pattern 220 includes a first
component 221 and a second component 222, which extend in an
X-direction and are arranged in parallel with each other, and a
third component 223 and a fourth component 224, which extend in a
Y-direction and are arranged in parallel with each other. Of these
components, the first component 221 and the second component 222
are used as two first direction (X-direction) components in the
first mark 210, for overlay measurement with respect to the upper
layer. Further, the third component 223 and the fourth component
224 are used as two second direction (Y-direction) components in
the first mark 210, for this overlay measurement. The outer pattern
230 includes a fifth component 231 and a sixth component 232, which
extend in the X-direction and are arranged in parallel with each
other, and a seventh component 233 and an eighth component 234,
which extend in the Y-direction and are arranged in parallel with
each other.
[0022] On the patterned first layer 111, a second layer 112 serving
as the upper layer is arranged, and a resist pattern 113 for
processing the second layer 112 is arranged on the second layer
112. The second layer 112 is a conductive film or the like to be
patterned in a subsequent step, for example. The second marks 310
are arranged in that part of the resist pattern 113, which is
present on the mark arrangement region 102. As illustrated in FIGS.
1A and 2B, each of the second marks 310 has a structure in which
line patterns are arranged in a quadrangular shape. Each second
mark 310 includes a ninth component 321 and a tenth component 322,
which extend in an X-direction and are arranged in parallel with
each other, and an eleventh component 323 and a twelfth component
324, which extend in a Y-direction and are arranged in parallel
with each other. Of these components, the ninth component 321 and
the tenth component 322 are used as two first direction
(X-direction) components in the second mark 310, for overlay
measurement with respect to the lower layer. Further, the eleventh
component 323 and the twelfth component 324 are used as two second
direction (Y-direction) components in the second mark 310, for this
overlay measurement. Further, in this example, for the second mark
310, the distance between the ninth component 321 and the tenth
component 322 and the distance between the eleventh component 323
and the twelfth component 324 are set such that, when the centers
of the first mark 210 and the second mark 310 are made to agree
with each other, the second mark 310 is present to have a
predetermined distance from the outer periphery of the inner
pattern 220 of the first mark 210. Here, in FIG. 2B, the first mark
210 in the lower layer is illustrated by broken lines.
[0023] Further, as illustrated in FIGS. 2A and 2B, each of the
components 221 to 224, 231 to 234; and 321 to 324 of the first mark
210 and the second mark 310 has a configuration in which the line
pattern is segmentized. Specifically, each of the components 221 to
224 and 231 to 234 of the first mark 210 has a configuration in
which a plurality of segments 261 are arranged in a line, and each
of the components 321 to 324 of the second mark 310 has a
configuration in which a plurality of segments 361 are arranged in
a line. Here, the segments 261 and 361 are arranged at a pitch,
with which the segments 261 and 361 cannot be resolved by light
having a wavelength of .lamda.1 used for the alignment measurement,
but the segments 261 and 361 can be resolved by light having a
wavelength of .lamda.2 (<.lamda.1) used for the overlay
measurement. Where, in a light exposure process, NA1 denotes the
numerical aperture of a position measuring unit used for the
alignment measurement, and NA2 denotes the numerical aperture of a
position measuring unit used for the overlay measurement, the pitch
P of the segments 261 and 361 is set to fall within a range
expressed by the following formula (1).
.lamda.2/NA2<P<.lamda.1/NA1 (1)
[0024] Further, for example, the width and length (size) of each of
the components 221 to 224 and 231 to 234 forming the first mark 210
are substantially equal to the width and length (size) of each of
the components 321 to 324 forming the second mark 310. The first
mark 210 and the second mark 310 having the configurations
described above are used as alignment marks in the alignment
measurement, and are used as overlay marks in the overlay
measurement. Further, the first mark 210 and the second mark 310
illustrated here are designed to be used in bright field
measurement.
[0025] Next, an explanation will be given of a position measuring
method and a semiconductor device manufacturing method. FIG. 4 is a
flowchart illustrating an example of the sequence of a
semiconductor device manufacturing method including a position
measuring method according to the embodiment. First, a second layer
112 is formed on a substrate 100 including a first layer 111
provided with first marks 210, and, thereafter, a resist is applied
onto the second layer 112 in a coating and developing apparatus
(step S11).
[0026] Then, the substrate 100 with the resist applied thereon is
placed on the stage of a light exposure apparatus (step S12).
Thereafter, in a position measuring unit of the light exposure
apparatus, an alignment measuring process using the first marks 210
is performed (step S13). Specifically, alignment measurement is
performed by irradiating the first marks 210 with light having the
wavelength of .lamda.1. FIG. 5 is a diagram illustrating an image
of a first mark in the alignment measurement. As described above,
since the segments 261 forming the first mark 210 cannot be
resolved by light having the wavelength of .lamda.1, when the first
mark 210 is irradiated with light having the wavelength of
.lamda.1, as illustrated in FIG. 5, the components 221 to 224 and
231 to 234 come to be not segmentized but recognized as line
patterns. In the light exposure apparatus, the center position of
each first mark 210 is acquired from the first mark 210 recognized
as line patterns, and this center position is used to detect the
position of the substrate 100 on the stage of the light exposure
apparatus.
[0027] FIG. 6 is a flowchart illustrating an example of an
alignment measuring process using the first marks. First, image
pickup is performed to each of the first marks 210 on the substrate
100 placed on the stage of the light exposure apparatus to obtain
an image of each first mark 210 (step S31). Then, from this image,
a first X-direction profile of the first mark 210 in the
X-direction is obtained (step S32). Here, as indicated by an arrow
A1 in FIG. 5, the first X-direction profile is obtained at
positions across the seventh component 233, the third component
223, the fourth component 224, and the eighth component 234, which
extend in the Y-direction. The first X-direction profile is
generated by reading an intensity of the image at the respective
positions on the arrow A1.
[0028] FIG. 7 is a diagram illustrating an example of X-direction
profiles in the alignment measuring process. In FIG. 7, the
horizontal axis indicates a position, and the vertical axis
indicates an intensity. In FIG. 7, the solid line illustrates the
first X-direction profile PR1.
[0029] Then, the image is reversed (step S33), and, from this
reverse image, a second X-direction profile of the first mark 210
in the X-direction is obtained (step S34). For example, the second
X-direction profile is obtained at the same positions on the arrow
A1 in the reverse image. In FIG. 7, the broken line illustrates the
second X-direction profile PR2.
[0030] Thereafter, the X-direction center position of the first
mark 210 is calculated using the first X-direction profile and the
second X-direction profile (step S35). For example, while the
overlaying position between the first X-direction profile PR1 and
the second X-direction profile PR2 in FIG. 7 is shifted, an inverse
autocorrelation therebetween is grasped, and the position highest
in this correlation is assumed as the center position of the first
mark 210.
[0031] Then, from the image described above, a first Y-direction
profile of the first mark 210 in the Y-direction is obtained (step
S36). Here, as indicated by an arrow A2 in FIG. 5, the first
Y-direction profile is obtained at positions across the fifth
component 231, the first component 221, the second component 222,
and the sixth component 232, which extend in the X-direction. The
first Y-direction profile is generated by reading the intensity of
the image at the respective positions on the arrow A2.
[0032] Further, from the reverse image, a second Y-direction
profile of the first mark 210 in the Y-direction is obtained (step
S37). For example, the second Y-direction profile is obtained at
the same positions on the arrow A2 in the reverse image.
Thereafter, the Y-direction center position of the first mark 210
is calculated using the first Y-direction profile and the second
Y-direction profile (step S38). The Y-direction center position is
calculated by using a method substantially the same as that for the
X-direction center position. As a result, the alignment measuring
process using each of the first marks 210 ends, and the processing
sequence returns to FIG. 4.
[0033] With reference to FIG. 4 again, in the light exposure
apparatus, a light exposure process using a photo mask including
the second marks 310 is performed (step S14). In this light
exposure process, light exposure is performed to the resist in a
state where the second marks 310 is set to overlap with the first
marks 210 in the first layer 111. Thereafter, the substrate 100 is
transferred from the light exposure apparatus to the coating and
developing apparatus, and a development process is performed to the
substrate 100 (step S15). Consequently, for example, as illustrated
in FIGS. 1B and 3, a resist pattern 113 is formed to include the
second marks 310 at positions corresponding to the arrangement
positions of the first marks 210 in the first layer 111.
Thereafter, the substrate 100 is placed on the stage of an overlay
inspection apparatus serving as a position measuring apparatus
(step S16).
[0034] Then, in the overlay inspection apparatus, an overlay
measuring process using the first marks 210 and the second marks
310 is performed (step S17). Specifically, overlay measurement is
performed by irradiating the first marks 210 and the second marks
310 with light having the wavelength of .lamda.2 shorter than the
wavelength of .lamda.1. FIGS. 8A and 8B are diagrams illustrating
an example of a first mark and a second mark. Here, FIG. 8A is a
diagram illustrating an image of a first mark and a second mark in
the overlay measurement, and FIG. 8B is a diagram illustrating an
example of how to give numbers to the segments of the first
component forming the first mark. As described above, since the
segments 261 and 361 forming the first mark 210 and the second mark
310 can be resolved by light having, the wavelength of .lamda.2,
when the first mark 210 and the second mark 310 are irradiated with
the light having the wavelength of .lamda.2, as illustrated in FIG.
8A, each of the components 221 to 224, 231 to 234, and 321 to 324
comes to be recognized as a pattern in which the segments 261 or
361 are arrayed in a line (which will be referred to as
"segmentized line pattern", hereinafter). In the overlay inspection
apparatus, the first mark 210 and the second mark 310, which are in
a state of including such segmentized line patterns, are used to
calculate an overlay deviation amount.
[0035] FIGS. 9A and 9B are a flowchart illustrating an example of
an overlay measuring process using the first marks and the second
marks. First, image pickup is performed to each region including a
first mark 210 and a second mark 310 on the substrate 100 placed on
the stage of the overlay inspection apparatus to obtain an image
including the first mark 210 and the second mark 310 (step
S51).
[0036] Then, in this image, a first region R1 is set to include the
i-th to j-th segments 261 from the X-direction negative side in the
first component 221 of the first mark 210 in the lower layer (step
S52). Here, as illustrated by an example in FIG. 8B, it is assumed
that each of the components 221 to 224, 231 to 234, and 321 to 324
forming the first mark 210 and the second mark 310 consists of
n-number of segments 261 or 361 ("n" is an integer of 2 or more).
Each of "i" and "j" is an integer of 1 or more and "n" or less, and
"i<j" is satisfied. Further, it is assumed that, in each of the
components 221 to 224, 231 to 234, and 321 to 324, the segments are
given numbers of "1, 2, . . . n" in the order from the end of the
X-direction negative side or the end of the Y-direction negative
side.
[0037] Then, in this image, a second region R2 is set to include
the k-th to m-th segments 261 from the X-direction negative side in
the second component 222 of the first mark 210 in the lower layer
(step S53). It is set such that, when the image is rotated by
180.degree. about the center of the first mark 210 or the second
mark 310, the second region R2 of the rotated image agrees in
position with the first region R1 of the original image. Here, each
of "k" and "m" is an integer of 1 or more and "n" or less, and
"k<m", "i.noteq.k", and "j.noteq.m" are satisfied. Further, "i",
"j", "k", and "m" satisfy the following formulas (2) and (3).
i+m=n+1 (2)
j+k=n+1 (3)
[0038] Further, in general, in the case of a pattern arranged at a
predetermined pitch, processing becomes unstable more at the end
portion than near the center. Accordingly, it is likely that the
position closer to the end portion is more disordered in size or
the like and the position closer to the center of the array is more
stable without disorder in size or the like. For this reason, it is
preferable to select a region including segments 261 or 361, which
satisfy "i.gtoreq.2", "j.ltoreq.n-1", "k.gtoreq.2", and
"m.ltoreq.n-1". Further, the first region R1 and the second region
R2 may include segments 261 present at positions the same as each
other. However, a case is excluded where all of the segments 261
included in the first region R1 are the same in position as those
in the second region R2. This is because the rotational center
position cannot be obtained in this case.
[0039] As described above, in the non-rotated image, the array of
numbers given to segments 261 to be selected as the first region R1
from the first component 221 is different from the array of numbers
given to segments 261 to be selected as the second region R2 from
the second component 222.
[0040] Then, from this image, a third X-direction profile of the
pattern of the first region R1 in the X-direction is obtained (step
S54). FIG. 10 is a diagram illustrating an example of X-direction
profiles in the overlay measuring process. In FIG. 10, the
horizontal axis indicates a position, and the vertical axis
indicates the intensity. In FIG. 10, the solid line illustrates the
third X-direction profile PR3.
[0041] Further, the image is rotated by 180.degree. in its plane
about the center of the first mark 210 or the second mark 310, and,
in this rotated image, a fourth X-direction profile of the pattern
of the second region R2 in the X-direction is obtained (step S55).
In FIG. 10, the broken line illustrates the fourth X-direction
profile PR4.
[0042] Then, the X-direction rotational center position of the
first mark 210 in the lower layer is calculated using the third
X-direction profile and the fourth X-direction profile (step S56).
Here, while the rotational center is shifted, the correlation
between the third X-direction profile and the fourth X-direction
profile is grasped, and the position highest in this correlation is
assumed as the rotational center position of the first mark
210.
[0043] Thereafter, in the image obtained in step S51, a third
region R3 is set to include the i-th to j-th segments 361 from the
X-direction negative side in the ninth component 321 of the second
mark 310 in the upper layer (step S57).
[0044] Further, in this image, a fourth region R4 is set to include
the k-th to m-th segments 361 from the X-direction negative side in
the tenth component 322 of the second mark 310 in the upper layer
(step S58).
[0045] Then, from this image, a fifth X-direction profile of the
pattern of the third region R3 in the X-direction is obtained (step
S59). Further, in the image rotated by 180.degree., a sixth
X-direction profile of the pattern of the fourth region R4 in the
X-direction is obtained (step S60). The position of the fourth
region R4 in the rotated image overlaps with the position of the
third region R3 in the non-rotated image.
[0046] Thereafter, the X-direction rotational center position of
the second mark 310 in the upper layer is calculated using the
fifth X-direction profile and the sixth X-direction profile (step
S61). Here, the rotational center position is calculated by using a
method substantially the same as that for the X-direction
rotational center position of the first mark 210.
[0047] Then, the difference between the X-direction rotational
center positions of the first mark 210 in the lower layer and the
second mark 310 in the upper layer is calculated as an X-direction
overlay deviation amount (step S62). With the procedures described
above, the X-direction overlay deviation amount is calculated.
Then, a Y-direction overlay deviation amount is calculated with
substantially the same procedures.
[0048] In the image obtained in step S51, a fifth region R5 is set
to include the i-th to j-th segments 261 from the Y-direction
negative side in the third component 223 of the first mark 210 in
the lower layer (step S63).
[0049] Further, in this image, a sixth region R6 is set to include
the k-th to m-th segments 261 from the Y-direction negative side in
the fourth component 224 of the first mark 210 in the lower layer
(step S64).
[0050] Then, from this image, a third Y-direction profile of the
pattern of the fifth region R5 in the Y-direction is obtained (step
S65). Further, in the image rotated by 180.degree., a fourth
Y-direction profile of the pattern of the sixth region R6 in the
Y-direction is obtained (step S66). The position of the sixth
region R6 in the rotated image overlaps with the position of the
fifth region R5 in the non-rotated image.
[0051] Thereafter, the Y-direction rotational center position of
the first mark 210 in the lower layer is calculated using the third
Y-direction profile and the fourth Y-direction profile (step S67).
Here, the rotational center position is calculated by using a
method substantially the same as that for the X-direction
rotational center position of the first mark 210.
[0052] Then, in the image obtained in step S51, a seventh region R7
is set to include the i-th to j-th segments 361 from the
Y-direction negative side in the eleventh component 323 of the
second mark 310 in the upper layer (step S68).
[0053] Further, in this image, an eighth region R8 is set to
include the k-th to m-th segments 361 from the Y-direction negative
side in the twelfth component 324 of the second mark 310 in the
upper layer (step S69).
[0054] Then, from this image, a fifth Y-direction profile of the
pattern of the seventh region R7 in the Y-direction is obtained
(step S70). Further, in the image rotated by 180.degree., a sixth
Y-direction profile of the pattern of the eighth region R8 in the
Y-direction is obtained (step S71). The position of the eighth
region R8 in the rotated image overlaps with the position of the
seventh region R7 in the non-rotated image.
[0055] Thereafter, the Y-direction rotational center position of
the second mark 310 in the upper layer is calculated using the
fifth Y-direction profile and the sixth Y-direction profile (step
S72). Here, the rotational center position is calculated by using a
method substantially the same as that for the X-direction
rotational center position of the first mark 210.
[0056] Then, the difference between the Y-direction rotational
center positions of the first mark 210 in the lower layer and the
second mark 310 in the upper layer is calculated as a Y-direction
overlay deviation amount (step S73). As a result, the overlay
deviation amounts are calculated, and the processing sequence
returns to FIG. 4.
[0057] With reference to FIG. 4 again, it is determined whether
each of the overlay deviation amounts obtained as overlay
measurement results in the overlay inspection apparatus falls
within a permissible range (step S18). When either one of the
overlay deviation amounts does not fall within the permissible
range (No at step S18), the resist pattern 113 on the substrate 100
subjected to the overlay measuring process is peeled off, and a
resist is newly applied onto the second layer 112 (step S19). Then,
the substrate 100 with the resist applied thereon is placed on the
stage of the light exposure apparatus (step S20), and the alignment
measuring process using the first marks 210 is performed in the
light exposure apparatus as in step S13 (step S21). Thereafter, in
the light exposure apparatus, a light exposure process is
performed, under light exposure conditions corrected for the
overlay deviation amounts obtained in step S17 to be closer to
zero, by using a photo mask including the second marks 310 (step
S22). Thereafter, the processing sequence returns to step S15.
[0058] On the other hand, in step S18, when each of the overlay
deviation amounts falls within the permissible range (Yes at step
S18), the resist pattern 113 including the second marks 310 is
transferred to the second layer 112 by, for example, anisotropic
etching, such as a Reactive Ion Etching (RIE) method. Consequently,
a processing object is obtained, in which the first layer 111 and
the second layer 112 are stacked and provided with the first marks
210 and the second marks 310 arranged with positional relationship
corresponding to each other. As a result, the processing sequence
ends.
[0059] It should be noted that, the marks described above are
designed to be used in bright field measurement, but the embodiment
described above may be applied also to marks designed to be used in
diffraction light measurement. FIGS. 11A and 11B are plan views
illustrating a configuration example of marks that can be used in
diffraction light measurement according to the embodiment. Here,
FIG. 11A is a view illustrating a configuration example of a first
mark, and FIG. 11B is a view illustrating a configuration example
of a second mark.
[0060] As illustrated in FIG. 11A, in the mark arrangement region
of the first layer, first marks 410 are arranged, which are to be
used for diffraction light measurement for performing X-direction
alignment. In each of the first marks 410, a plurality of line
patterns 411 extending in the Y-direction are arranged in parallel
with each other in the X-direction. Each of the line patterns 411
is divided into a plurality of segments 461. Specifically, the
plurality of segments 461 are arranged in the Y-direction at a
pitch expressed by the formula (1) to form each line pattern 411.
Consequently, in alignment measurement using light having the
wavelength of .lamda.1, the segments 461 are not resolved, and the
line patterns 411 come to diffract light having the wavelength of
.lamda.1. Further, in overlay measurement using light having the
wavelength of .lamda.2 shorter than the wavelength of .lamda.1, the
segments 461 are resolved.
[0061] As illustrated in FIG. 11B, in the mark arrangement region
of the resist pattern on the second layer, second marks 510 are
arranged, in each of which two line patterns extending in the
Y-direction are arranged in parallel with each other and to face
each other in the X-direction. Each second mark 510 includes a
first component 511 and a second component 512. Each of the first
component 511 and the second component 512 is divided into a
plurality of segments 561. Specifically, in each of the first
component 511 and the second component 512, the plurality of
segments 461 are arranged in the Y-direction at a pitch expressed
by the formula (1) to form a line pattern.
[0062] Further, in this example, for the second mark 510, the
distance between the first component 511 and the second component
512 is set such that, when the centers of the first mark 410 and
the second mark 510 are made to agree with each other, the second
mark 510 is present to have a predetermined distance from each of
the line patterns 411 of the first mark 410 arranged at the ends in
the X-direction. Here, in FIG. 11B, the first mark 410 in the lower
layer is illustrated by broken lines.
[0063] In this case, the overlay measurement is performed by bright
field measurement. A method for the bright field measurement is
basically the same as that illustrated in FIG. 8A. However, since
the marks illustrated in FIGS. 11A and 11B are marks for
calculating an overlay deviation amount in the Y-direction, only a
Y-direction overlay deviation amount is calculated. Accordingly, as
illustrated in FIG. 11B, regions of from a first region R1 to a
fourth region R4 are set to include segments 461 or 561 for
performing the overlay measurement. Here, it is assumed that each
of the line patterns of the first mark 410 and the second mark 510
consists of n-number of segments 461 or 561.
[0064] In the first mark 410 in the lower layer, some of the
segments 461 in line patterns 411 arranged equidistantly from the
X-direction center of the first mark 410 are used to perform the
overlay measurement. FIG. 11B illustrates a case where some of the
segments 461 in the line patterns 411 arranged at the opposite ends
in the X-direction are used to perform the overlay measurement. The
first region R1 is set as a region that includes the i-th to j-th
segments 461 from the Y-direction negative side, of the segments
461 in the line pattern 411 arranged at the end on the X-direction
negative side. The second region R2 is set as a region that
includes the k-th to m-th segments 461 from the Y-direction
negative side, of the segments 461 in the line pattern 411 arranged
at the end on the X-direction positive side. Here, each of "i",
"j", "k", and "m" is an integer of 1 or more and "n" or less, and
"i"<"j", "k<m", "i.noteq.k", and "j.noteq.m" are satisfied.
Also in this case, it is preferable to select a region including
segments 461, which satisfy "i.gtoreq.2", "j.ltoreq.n-1",
"k.gtoreq.2", and "m.ltoreq.n-1".
[0065] In the second mark 510 in the upper layer, the third region
R3 is set as a region that includes the i-th to j-th segments 561
from the Y-direction negative side in the first component 511. The
fourth region R4 is set as a region that includes the k-th to m-th
segments 561 from the Y-direction negative side in the second
component 512. The first mark 410 and the second mark 510
illustrated in FIGS. 11A and 11B are used as described above, and
thereby X-direction alignment measurement and Y-direction overlay
measurement can be performed.
[0066] In a case where the first mark 410 and the second mark 510
illustrated in FIGS. 11A and 11B are used, the mark arrangement
region 102 is provided with not only this set of first mark 410 and
second mark 510, but also another set of first mark 410 and second
mark 510 that is in a state rotated by 90.degree. in the plane of
figures with respect to the first mark 410 and the second mark 510
illustrated in FIGS. 11A and 11B. Consequently, Y-direction
alignment measurement and X-direction overlay measurement can be
also performed.
[0067] The alignment measuring process using the first marks 210
illustrated in FIG. 6 is executed by a controller provided to the
light exposure apparatus, for example. The overlay measuring
process using the first marks 210 and the second marks 310
illustrated in FIGS. 9A and 9B is executed by a controller provided
to the position measuring apparatus, for example.
[0068] FIG. 12 is diagram illustrating a hardware configuration
example of a controller for each of the light exposure apparatus
and the position measuring apparatus. The controller 600 has a
hardware configuration utilizing an ordinary computer, in which a
Central Processing Unit (CPU) 611, a Read Only Memory (ROM) 612, a
Random Access Memory (RAM) 613 serving as the main storage device,
an external storage device 614, such as a Hard Disk Drive (HDD),
Solid State Drive (SSD), or Compact Disc (CD) drive device, a
display unit 615, such as a display device, and an input unit 616,
such as a keyboard and/or a mouse, are included, and are connected
to each other via a bus line 617.
[0069] A program to be executed by the controller 600 according to
this embodiment has been prepared to perform the alignment
measuring process using the first marks 210 illustrated in FIG. 6,
or the overlay measuring process using the first marks 210 and the
second marks 310 illustrated in FIGS. 9A and 9B. This program is
provided in a state recorded in a computer-readable recording
medium, such as a CD-ROM, flexible disk (FD), CD-R, or Digital
Versatile Disk (DVD), by a file in an installable format or
executable format.
[0070] Alternatively, a program to be executed by the controller
600 according to this embodiment may be provided such that the
program is stored in a computer connected to a network, such as the
internet, and is downloaded via the network. Further, a program to
be executed by the controller 600 according to this embodiment may
be provided such that the program is provided or distributed via a
network, such as the internet.
[0071] Alternatively, a program according to this embodiment may be
provided in a state incorporated in an ROM or the like in
advance.
[0072] According to the embodiment, each of the line patterns
forming the marks is configured by arranging a plurality of
segments in a state where the segments cannot be resolved by light
having the wavelength of .lamda.1 used for the alignment
measurement but can be resolved by light having the wavelength of
.lamda.2 (<.lamda.1) used for the overlay measurement.
Consequently, the same mark can be used for either of the alignment
measurement and the overlay measurement, and thus the number of
marks to be arranged in the mark arrangement region 102 can be
reduced. As a result, the area of the mark arrangement region 102
can be set smaller, while the area of the pattern arrangement
region 101 can be set larger. This makes it possible to increase
the storage capacity of a semiconductor memory device, for
example.
[0073] While certain embodiments have been described, these
embodiments have been presented by way of example only, and are not
intended to limit the scope of the inventions. Indeed, the novel
embodiments described herein may be embodied in a variety of other
forms; furthermore, various omissions, substitutions and changes in
the form of the embodiments described herein may be made without
departing from the spirit of the inventions. The accompanying
claims and their equivalents are intended to cover such forms or
modifications as would fall within the scope and spirit of the
inventions.
* * * * *