U.S. patent application number 17/398107 was filed with the patent office on 2021-11-25 for glass substrate, laminated substrate, laminated substrate manufacturing method, laminate, package, and glass substrate manufacturing method.
This patent application is currently assigned to AGC Inc.. The applicant listed for this patent is AGC Inc.. Invention is credited to Keisuke Hanashima, Yu Hanawa, Shuhei Nomura, Kazutaka Ono, Nobuhiko Takeshita.
Application Number | 20210366760 17/398107 |
Document ID | / |
Family ID | 1000005767358 |
Filed Date | 2021-11-25 |
United States Patent
Application |
20210366760 |
Kind Code |
A1 |
Hanawa; Yu ; et al. |
November 25, 2021 |
GLASS SUBSTRATE, LAMINATED SUBSTRATE, LAMINATED SUBSTRATE
MANUFACTURING METHOD, LAMINATE, PACKAGE, AND GLASS SUBSTRATE
MANUFACTURING METHOD
Abstract
A glass substrate is laminated with a substrate containing
silicon to thereby form a laminated substrate. The glass substrate
has a concave surface and a convex surface and has one or more
marks that distinguish between the concave surface and the convex
surface.
Inventors: |
Hanawa; Yu; (Tokyo, JP)
; Nomura; Shuhei; (Tokyo, JP) ; Ono; Kazutaka;
(Tokyo, JP) ; Takeshita; Nobuhiko; (Tokyo, JP)
; Hanashima; Keisuke; (Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
AGC Inc. |
Tokyo |
|
JP |
|
|
Assignee: |
AGC Inc.
Tokyo
JP
|
Family ID: |
1000005767358 |
Appl. No.: |
17/398107 |
Filed: |
August 10, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15877509 |
Jan 23, 2018 |
11133215 |
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17398107 |
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PCT/JP2016/071172 |
Jul 19, 2016 |
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15877509 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B32B 17/10036 20130101;
H01L 2223/54493 20130101; H01L 21/67282 20130101; H01L 21/68757
20130101; G05B 1/00 20130101; B65D 85/48 20130101; C03B 33/02
20130101; H01L 21/56 20130101; C03C 27/10 20130101; B32B 17/10889
20130101; C03B 33/0235 20130101; H01L 23/544 20130101 |
International
Class: |
H01L 21/687 20060101
H01L021/687; C03B 33/02 20060101 C03B033/02; B65D 85/48 20060101
B65D085/48; H01L 21/67 20060101 H01L021/67; G05B 1/00 20060101
G05B001/00; H01L 23/544 20060101 H01L023/544; C03C 27/10 20060101
C03C027/10; B32B 17/10 20060101 B32B017/10; C03B 33/023 20060101
C03B033/023; H01L 21/56 20060101 H01L021/56 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 24, 2015 |
JP |
2015-147249 |
Dec 28, 2015 |
JP |
2015-256895 |
Claims
1-22. (canceled)
23. A glass substrate to be laminated with a substrate containing
silicon to thereby form a laminated substrate, the glass substrate
having a concave surface and a convex surface, the glass substrate
having one or more marks that distinguish between the concave
surface and the convex surface, wherein the one or more marks are
marks formed on at least one of the concave surface and the convex
surface, and wherein the concave surface and the convex surface
differ from each other in the number of the marks formed
thereon.
24. The glass substrate according to claim 23, wherein the concave
surface has the one or more marks and the convex surface has no
mark.
25. The glass substrate according to claim 23, wherein at least one
of the one or more marks that distinguish between the concave
surface and the convex surface is a depression.
26. The glass substrate according to claim 25, wherein the
depression has a shape of a letter or symbol.
27. The glass substrate according to claim 23, wherein at least one
of the concave surface and the convex surface has an area of
70-2,000 cm.sup.2.
28. The glass substrate according to claim 23, which has a circular
shape.
29. The glass substrate according to claim 23, which has a Young's
modulus of 65 GPa or higher.
30. The glass substrate according to claim 23, which contains, as
represented by mole percentage based on oxides, 0-0.1% of an alkali
metal oxide.
31. The glass substrate according to claim 23, which has a
deviation of plate thickness of 15 .mu.m or less.
32. The glass substrate according to claim 23, which has a
light-shielding film on at least one of the concave surface and the
convex surface.
33. A laminated substrate formed by pasting the convex surface of
the glass substrate according to claim 23 to a substrate containing
silicon.
34. A laminated substrate comprising the glass substrate according
to claim 23 and a substrate containing silicon, wherein a curved
surface constituted of the convex surface or concave surface of the
glass substrate and a curved surface constituted of a convex
surface or a concave surface of the substrate containing silicon
are pasted to each other so as to conform to each other.
35. A laminate comprising the laminated substrate according to
claim 33 and another glass substrate that is pasted to the glass
substrate.
36. A package formed by packaging two or more glass substrates
according to claim 23, wherein the glass substrates are packaged so
that the convex surface of one of the glass substrates faces the
concave surface of another glass substrate.
37. A package formed by packaging two or more laminated substrates
according to claim 33, wherein the laminated substrates are
packaged so that the substrate containing silicon of one of the
laminated substrates faces the concave surface of the glass
substrate of another laminated substrate.
38. A package formed by packaging two or more laminates according
to claim 35, wherein the substrate containing silicon of one of the
laminates faces the concave surface of the glass substrate of
another laminate.
39. The package according to claim 36, wherein the concave surface
of the glass substrate is supported at four points by a supporting
member.
40. A process for producing the glass substrate according to claim
23, the process comprising: heating raw materials for glass to
obtain molten glass; forming the molten glass into a plate shape to
obtain a glass ribbon; slowly cooling the glass ribbon to obtain a
cooled glass ribbon; cutting the cooled glass ribbon to obtain an
unmarked glass substrate; distinguishing between a concave surface
and a convex surface of the unmarked glass substrate; and placing a
mark on at least one of the concave surface and the convex surface
to obtain the glass substrate.
Description
TECHNICAL FIELD
[0001] The present invention relates to a glass substrate, a
laminated substrate, a process for producing the laminated
substrate, a laminate, packages, and a process for producing the
glass substrate.
BACKGROUND ART
[0002] In a field of semiconductor devices, a degree of integration
in devices is increasing, while size reductions are proceeding.
There is accordingly a growing desire fora technique for packaging
devices having a high degree of integration. In conventional
semiconductor assembly steps, a glass substrate and a substrate
containing silicon, both in a wafer state, are separately cut, and
the glass substrate and the substrate containing silicon are then
stuck to each other and subjected to a series of assembly steps
including die bonding, wire bonding, and molding.
[0003] In recent years, a wafer-level packaging technique is being
highlighted in which a glass substrate and a substrate containing
silicon, both in a full-size wafer state, are stuck to each other
and the laminate is subjected to assembly steps and then cut. In
Patent Document 1, for example, a supporting glass substrate for
use in wafer-level packaging is proposed.
PRIOR ART DOCUMENT
Patent Document
[0004] Patent Document International Publication WO 2015/037478
SUMMARY OF THE INVENTION
Problem that the Invention is to Solve
[0005] In the production of glass substrates, a completely flat
glass is difficult to produce on a mass production level, and there
is a problem in that a glass substrate having waviness is produced.
In wafer-level packaging, in cases where a glass substrate having
waviness is used in sticking, the glass substrate to a substrate
containing silicon to obtain a laminated substrate, there is a
problem in that a space is prone to be formed between the glass
substrate and the substrate containing silicon, resulting in bubble
inclusion.
[0006] Accordingly, the present invention provides a glass
substrate which, when used in sticking the glass substrate to a
substrate containing silicon to obtain a laminated substrate. is
less apt to cause bubble inclusion between the glass substrate and
the substrate containing silicon, and further provides a laminated
substrate, a process for producing the laminated substrate, a
laminate, packages, and a process for producing the glass
substrate.
Means for Solving the Problems
[0007] A glass substrate according to the present invention is a
glass substrate to be laminated with a substrate containing silicon
to thereby form a laminated substrate, the glass substrate having a
concave surface and a convex surface and having one or more marks
that distinguish between the concave surface and the convex
surface.
[0008] A laminated substrate according to the present invention is
formed by laminating the convex surface of the glass substrate to a
substrate containing silicon.
[0009] A process according to the present invention for producing a
laminated substrate includes sticking (pasting) a curved surface
constituted of the convex surface or concave surface of the glass
substrate and a curved surface constituted of a convex surface or
concave surface of a substrate containing silicon to each other so
as to conform to each other.
[0010] A laminate according to the present invention includes the
laminated substrate and another glass substrate that is stuck
(pasted) to the glass substrate that is a component of the
laminated substrate.
[0011] A package according to the present invention is formed by
packaging two or more glass substrates, wherein the glass
substrates are packaged so that the convex surface of one of the
glass substrates faces the concave surface of another glass
substrate.
[0012] A package according to the present invention is formed by
packaging two or more laminated substrates, wherein the laminated
substrates are packaged so that the substrate containing silicon
that is a component of one of the laminated substrates faces the
concave surface of the glass substrate that is a component of
another laminated substrate.
[0013] A package according to the present invention is formed by
packaging two or more laminates, wherein the substrate containing
silicon that is a component of one of the laminates faces the
concave surface of the glass substrate that is a component of
another laminate.
[0014] A process according to the present invention is a process
for producing a glass substrate to be laminated with a substrate
containing silicon to thereby form a laminated substrate, the
process including: [0015] a melting step of heating raw materials
for glass to obtain a molten glass; [0016] a forming step of
forming the molten glass into a plate shape to obtain a glass
ribbon; [0017] a slow cooling step of slowly cooling the glass
ribbon; [0018] a cutting step of cutting the glass ribbon to obtain
a glass substrate; [0019] an inspection step of discriminating a
concave surface and a convex surface in the glass substrate; and
[0020] a step of placing a mark on at least one of the concave
surface and the convex surface, thereby obtaining the glass
substrate.
Effect of the Invention
[0021] According to the glass substrate, laminated substrate,
process for producing the laminated substrate, laminate, packages,
and process for glass substrate production of the present
invention, bubble inclusion is less apt to occur between the glass
substrate and a substrate containing silicon in sticking the glass
substrate to the substrate containing silicon to obtain a laminated
substrate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1A and FIG. 1B show a glass substrate of a first
embodiment of the present invention which is stuck to a substrate
containing silicon; FIG. 1A is a cross-sectional view illustrating
the glass substrate which has not been stuck, and FIG. 1B is a
cross-sectional view of the glass substrate which has been
stuck.
[0023] FIG. 2A to FIG. 2C show a glass substrate of the first
embodiment of the present invention; FIG. 2A is a top view, FIG. 2B
is a bottom view, and FIG. 2C is a cross-sectional view.
[0024] FIG. 3A to FIG. 3B show a glass substrate in which notches
are formed as marks; FIG. 3A is a top view, FIG. 3B is a bottom
view, and FIG. 3C is a cross-sectional view.
[0025] FIG. 4A and FIG. 4B are cross-sectional views which
illustrate how a glass substrate of the first embodiment of the
present invention is stuck to a substrate containing silicon.
[0026] FIG. 5A to FIG. 5C illustrate how a glass substrate of the
first embodiment of the present invention is supported by
supporting members; FIG. 5A is a plan view, and FIG. 5B and FIG. 5C
are cross-sectional views.
[0027] FIG. 6A to FIG. 6C illustrate how a glass substrate of the
first embodiment of the present invention is supported by
supporting members; FIG. 6A is a plan view, and FIG. 6B and FIG. 6C
are cross-sectional views.
[0028] FIG. 7A to FIG. 7C show a glass substrate of a second
embodiment of the present invention; FIG. 7A is a top view, FIG. 7B
is a bottom view, and FIG. 7C is a cross-sectional view.
[0029] FIG. 8A to FIG. 8C show a glass substrate of a third
embodiment of the present invention; FIG. 8A is a top view, FIG. 8B
is a bottom view, and FIG. 8C is a cross-sectional view.
[0030] FIG. 9A to FIG. 9C show a glass substrate of the third
embodiment of the present invention; FIG. 9A is a top view, FIG. 9B
is a bottom view, and FIG. 9C is a cross-sectional view.
[0031] FIG. 10 is a cross-sectional view of a package according to
one embodiment of the present invention.
[0032] FIG. 11 is a cross-sectional view of a package according to
one embodiment of the present invention.
[0033] FIG. 12A and FIG. 12B are cross-sectional views for
illustrating relationships between a curved surface of a glass
substrate and a curved surface of a substrate containing silicon in
a step for producing a laminated substrate.
MODES FOR CARRYING OUT THE INVENTION
[0034] Embodiments of the present invention are explained below in
detail by reference to the drawings.
[0035] First, glass substrates according to a first embodiment of
the present invention are explained. FIG. 1A and FIG. 1B are
cross-sectional views of a glass substrate of the first embodiment
of the present invention which is stuck to a substrate containing
silicon,
[0036] The glass substrate G1 of the first embodiment of the
present invention shown in FIG. 1A is stuck to a substrate
containing silicon 10 at an ambient temperature of, for example,
200.degree. C.-400.degree. C., with a resin 20 interposed
therebetween, thereby obtaining a laminated substrate 30 shown in
FIG. 1B.
[0037] As the substrate containing silicon 10, use is made, for
example, of a full-size wafer (e.g., silicon wafer).
[0038] The substrate containing 10 may be, for example, a wafer
having elements formed thereon or a substrate including chips of
elements (e.g., silicon chips) cut out of a wafer and molded by
resin. Furthermore, the substrate 10 may be a substrate configured
of a silicon substrate, e.g., a silicon wafer or silicon chips, and
a non-silicon substrate such as a glass substrate, e.g., TGV, or a
resin substrate. In this case, the silicon substrate and the glass
substrate are connected to each other by wiring with copper,
etc.
[0039] The resin 20 is a resin capable of withstanding temperatures
of, for example, 200.degree. C.-400.degree. C.
[0040] The glass substrate of the first embodiment of the present
invention is suitable for use as a supporting glass substrate for
fan-out type wafer-level packages. The glass substrate is suitable
also as a glass substrate for image sensors, such as MEMS, CMOS,
and CIS, for which element size reduction by wafer-level packaging
is effective, and as a substrate having through-holes formed
therein which is for use as a glass interposer (GIP) and a support
glass for semiconductor back grinding.
[0041] The glass substrate of the first embodiment of the present
invention has no waviness and has such curved surfaces that one of
the main surfaces is a concave surface and the other main surface,
which is faces said main surface, is a convex surface.
[0042] The term "convex surface" or "concave surface" as used in
the present invention means whether a curved surface is a
macroscopically convex surface or concave surface distinguished
using the SEMI standards. Consequently, the expression "having no
waviness" used for the glass substrate of the first embodiment does
not mean that there is no microscopic waviness in the glass
substrate.
[0043] Whether a surface is a "convex surface" or "concave surface"
according to the present invention may be determined specifically
by using BOW (MF534) or WARP (MF657, MF1390) of the SEMI standards.
In the case of even warpage, BOW may be used. In the case where
there is waviness, WARP may be used.
[0044] According to BOW, the substrate is held unclamped, and the
warpage is expressed in terms of distance from a designated
reference plane to the surface of the substrate center.
[0045] The surface located on a reference plane side is regarded as
a concave surface, and the surface on a reverse side from the
concave surface is regarded as a convex surface. The reference
plane is determined by a substrate-thickness center line.
[0046] According to WARP, the substrate is held unclamped, and the
warpage is expressed in terms of a difference between a maximum
value and a minimum value of the distance between a designated
reference plane and the substrate center plane. The reference plane
is determined by the least square method, and the substrate center
plane is set so that the difference between the maximum value and
the minimum value is minimum. The surface on a side where the
distance has the maximum value is regarded as a convex surface, and
the surface on a side where the distance has the minimum value is
regarded as a concave surface.
[0047] From a macroscopic standpoint, the convex surface has no
reverse warpage which constitutes a recess. It is preferable that
the convex surface should have a small curvature, from the
standpoint of preventing the laminated substrate from warping
considerably. It is hence difficult to determine which surface is a
concave surface or a convex surface, when sticking to a substrate
containing silicon. It is therefore necessary to place marks with
which the concave surface can be distinguished from the convex
surface.
[0048] FIG. 2A to FIG. 2C show a glass substrate G1 of the first
embodiment of the present invention; FIG. 2A is a top view, FIG. 2B
is a bottom view, and FIG. 2C is a cross-sectional view.
[0049] The glass substrate G1 of the first embodiment of the
present invention is a glass substrate to be laminated with a
substrate containing silicon to thereby form a laminated substrate.
The glass substrate G1 has a concave surface G1A and a convex
surface G1B and having marks which distinguish between the concave
surface G1A and the convex surface G1B, Since this glass substrate
G1 has marks which distinguish between the concave surface G1A and
the convex surface G1B the concave surface G1A and convex surface
G1B of the glass substrate G1 can be distinguished from each other
and, hence, in sticking (pasting) the glass substrate G1 to a
substrate containing silicon to obtain a laminated substrate, the
convex surface G1B of the glass substrate G1 is stuck (pasted) to
the substrate containing silicon to thereby render bubble inclusion
less apt to occur between the glass substrate G1 and the substrate
containing silicon. In case where bubble inclusion has occurred,
the substrate containing silicon as a component of the laminated
substrate has impaired flatness and has an increased deviation of
plate thickness in a step of grinding the substrate containing
silicon, rendering a patterning in a subsequent step difficult. In
addition, in cases where such a laminated substrate is heated, the
glass substrate is prone to be separated from the substrate
containing silicon because of the expansion of the bubbles. The
glass substrate G1 of the first embodiment of the present
invention, when being stuck, is less apt to suffer bubble inclusion
between the glass substrate G1 and the substrate containing
silicon. Because of this, the substrate containing silicon as a
component of the laminated substrate has satisfactory flatness and
has a small deviation of plate thickness in the step of grinding
the substrate containing silicon, thereby facilitating the
patterning in a subsequent step. Furthermore, even when the
laminated substrate is heated, the glass substrate and the
substrate containing silicon are less apt to separate from each
other.
[0050] The glass substrate G1 of the first embodiment of the preset
invention includes two marks 130 and 140 for distinguishing the
concave surface G1A and the convex surface G1B from each other, the
marks 130 and 140 having been formed on the concave surface G1A and
differing in shape from each other, and further includes two marks
150 and 160 for distinguishing the concave surface G1A and the
convex surface G1B from each other, the marks 150 and 160 having
been formed on the convex surface G1B in positions respectively
facing the two marks 130 and 140 formed on the concave surface G1A,
the marks 150 and 160 being equal in shape to the respective
corresponding marks formed on the concave surface G1A. It is
preferable that a shortest line L by which the two marks 150 and
160 on the convex surface G1B are connected to each other on the
convex surface G1B should not pass through the center of gravity F
on the convex surface G1B. This is for more reliably distinguishing
the concave surface G1A and the convex surface G1B, as will be
described later. Due to these marks 150, 160, 130, and 140, the
concave surface G1A and the convex surface G1B of the glass
substrate G1 cart be distinguished.
[0051] The marks may be, for example coating materials, or may be
recesses formed with a laser or the like. The expression "the glass
substrate G1 includes two marks 130 and 140 formed on the concave
surface G1A and differing in shape from each other and further
includes two marks 150 and 160 formed on the convex surface G1B in
positions respectively facing the two marks 130 and 140 formed on
the concave surface G1A and are equal in shape to the respective
corresponding marks formed on the concave surface G1A" means that
the two marks 130 and 140 on the concave surface G1A may have been
formed so as to pierce the glass substrate and extend to the convex
surface G1B to constitute the two marks 150 and 160 on the convex
surface G1B. Examples of such marks include through-holes formed by
a laser or the like and cutouts, such as notches and orientation
flats (hereinafter referred to also as OFs), which are armed in the
edge of the glass substrate G1.
[0052] OFs are cutouts in a shape of a circular arc framed by
cutting an edge of a glass substrate. Notches are cutouts in a
shape of a letter V or U formed in an edge of a glass substrate.
FIG. 3A to FIG. 3C show a glass substrate in which notches are
formed as marks; FIG. 3A is a top view, FIG. 3B is a bottom view,
and FIG. 3C is a cross-sectional view.
[0053] The positions of the cutouts in the glass substrate G1 can
be detected, for example, with a laser. The cutouts may be detected
by taking an image of the glass substrate with a camera and
analyzing the image. In cases where the marks are cutouts, the
position and angle of the substrate containing silicon 10 can be
specified on the basis of the cutouts when forming circuit patterns
on the substrate containing silicon 10. Thus, the circuit patterns
can be inhibited from suffering a dimensional dislocation.
[0054] In cases where the cutouts are notches as in FIG. 3A to FIG.
3C, the glass substrate G1 has a small area loss and is apt to be
easily stuck to a substrate containing silicon 10. In cases where
the cutouts are OFs, the cutouts can be easily formed and the
positions of the cutouts are easy to detect.
[0055] It is preferable that the marks should lie within a region
ranging from the edge of the glass substrate G1 to 20 mm therefrom.
In cases where the marks lie within the region ranging from the
edge of the glass substrate G1 to 20 mm therefrom, these marks do
not interfere with circuit patterns to be formed on the substrate
containing silicon, The positions of the marks are more preferably
within a region ranging from the edge of the glass substrate G1 to
10 min therefrom, even more preferably within a region ranging from
the edge of the glass substrate G1 to 5 mm therefrom, especially
preferably at the edge of the glass substrate.
[0056] It is preferable that the marks should be formed by cutting
the edge of the glass substrate G1. Examples of such marks include
the notches and OFs described above.
[0057] Methods for distinguishing the concave surface G1A and the
convex surface G1B from each other are explained here. It is
assumed that there are two marks 150 and 160 differing in shape and
the mark 150 is larger than the mark 160, for example, as shown in
FIG. 2A. It is assumed that the marks 150 and 160 are circular
through-holes and that the mark 150 is identical with the mark 130
and the mark 160 is identical with the mark 140.
[0058] For example, in FIG. 2A, in which the convex surface G1B is
an upper surface, a mark 160 is formed in a region ranging to less
than 180.degree. counterclockwise from the mark 150 with respect to
the center of gravity F on the convex surface G1B of the glass
substrate G1 (a region in FIG. 2A in which .theta. is less than
180.degree.). In this case, if the mark 160 lies in a region (where
.theta. is less than 180.degree.) ranging, to less than 180.degree.
counterclockwise from the mark 150 with respect to the center of
gravity F on the convex surface G1B of the glass substrate G1, then
this surface is found to be a convex surface G1B. If the mark 160
lies in a region (where .theta. is larger than 180.degree.) ranging
to more than 180.degree. counterclockwise from the mark 150 with
respect to the center of gravity I of the glass substrate G1, as in
FIG. 2B, then this surface is found to be a concave surface
G1A.
[0059] In case where a mark 160 is formed at a position where
.theta. is 180.degree., the concave surface G1A cannot be
distinguished from the convex surface G1B. In case where a mark 160
is formed at a position where .theta. is 180.degree., a shortest
line by which the two marks 150 and 160 on the convex surface CAB
are connected to each other on the convex surface G1B passes
through the center of gravity F on the convex surface G1B.
[0060] In the glass substrate G1 of the first embodiment of the
present invention, it is preferable that the shortest line by which
the two marks 150 and 160 on the convex surface G1B are connected
to each other should not pass through the center of gravity F on
the convex surface. In cases where marks 150 and 160 are formed in
such positions, .theta. is not 180.degree. and it is possible to
distinguish the concave surface G1A and convex surface G1B.
[0061] The shortest line by which the two marks 150 and 160 on the
convex surface G1B are connected to each other does not pass
preferably through a region ranging to 1 mm from the center of
gravity F on the convex surface, more preferably through a region
ranging to 5 mm therefrom, even more preferably through a region
ranging to 10 mm therefrom. The positions of the marks 150 and 160
can be specified, for example, by taking an image of the convex
surface G1B of the glass substrate G1 with a camera and analyzing
the image.
[0062] FIG. 4A and FIG. 4B are cross-sectional views which
illustrate how a glass substrate of the first embodiment of the
present invention is stuck to a substrate containing silicon.
[0063] FIG. 4A shows how the glass substrate G1 is stuck to a
substrate containing silicon 10, with a resin 20 interposed
therebetween, so that the convex surface G1B of the glass substrate
G1 is a sticking surface. In cases where the glass substrate G1 is
stuck to a substrate containing silicon 10 in this manner, a space
is less apt to be formed between the glass substrate and the
substrate containing silicon 10 and hence, bubble inclusion is less
apt to occur.
[0064] FIG. 4B shows a laminated substrate 30 formed by sticking
the convex surface G1B of the glass substrate G1 to the substrate
containing silicon 10, with a resin 20 interposed therebetween. The
laminated substrate 30 thus formed by sticking the glass substrate
G1 to the substrate containing silicon 10 is less apt to have
bubbles between the glass substrate G1 and the substrate containing
silicon 10. Furthermore, residual stress is less apt to generate in
the glass substrate G1 and the substrate containing silicon 10, and
the laminated substrate 30 is less apt to suffer cracking or
chipping. In addition, stress is less apt to be imposed on the
wiring and the wiring is less apt to break.
[0065] FIG. 5A to FIG. 5C and FIG. 6A to FIG. 6C illustrate how the
glass substrate of the first embodiment of the present invention is
supported by supporting members. FIG. 5A and FIG. 6A are plan
views, and FIG. 5B, FIG. 5C, FIG. 6B, and FIG. 6C are
cross-sectional views. FIG. 5B and FIG. 6B are cross-sectional
views illustrating a state in which the convex surface G1B is
supported, while FIG. 5C and FIG. 6C are cross-sectional views
illustrating a state in which the concave surface G1A is
supported.
[0066] It is preferable that the glass substrate G1 of the first
embodiment of the present invention should be supported at four
points by supporting members 110 as shown in FIG. 5A. Because of
advantages including a reduced contact area, the glass substrate
G1, when being stored and transported, can be prevented from
suffering surface contamination with dust, etc.
[0067] In this case, the glass substrate G1 bends due to its own
weight. Because of this, in cases where the glass substrate G1,
with the convex surface G1B supported by supporting members 110 as
shown in FIG. 5B, is stored and transported, this glass substrate
G1 is prone to deform due to the bending. Meanwhile, in cases where
the glass substrate G1, with the concave surface G1A supported by
supporting members 110 as shown in FIG. 5C, is stored and
transported, this glass substrate G1 is less apt to deform. This
supporting method is hence preferred. The glass substrate G1 may be
supported at two sides by supporting members 120 as shown in FIG.
6A to FIG. 6C. By supporting the glass substrate G1 at two sides,
the glass substrate G1 can be stably stored and transported.
Furthermore, the glass substrate G1, when being stored and
transported, can be prevented from suffering surface contamination
with dust, etc. It is more preferred to support the concave surface
G1A of the glass substrate G1 as shown in FIG. 6C, since the glass
substrate G1 is less apt to deform.
[0068] It is preferable that, in the glass substrate G1 of the
first embodiment of the present invention, when the glass substrate
G1 has been placed on a horizontal plane so that the concave
surface G1A is in contact with the horizontal plane and when a
thickness of the glass substrate is expressed by V (unit: mm) and a
shortest distance between the center of gravity of the convex
surface G1B and the horizontal plane is expressed by U (unit: mm),
U/V should be 0.05-50. In cases where U/V is 0.05 or larger, bubble
inclusion is made less apt to occur between the glass substrate G1
and the substrate containing silicon in sticking the glass
substrate G1 to a substrate containing silicon to obtain a
laminated substrate, by sticking the convex surface G1B of the
glass substrate G1 to the substrate containing silicon. U/V is more
preferably 1 or larger, even more preferably 5 or larger. In cases
where UN is 50 or less, this glass substrate G1 can be easily stuck
to a substrate containing silicon, U/V is more preferably 30 or
less, even more preferably 10 or less.
[0069] Next, glass substrates according to a second embodiment of
the present invention are explained.
[0070] FIG. 7A to FIG. 7C show a glass substrate G2 of the second
embodiment of the present invention; FIG. 7A is a top view, FIG. 7B
is a bottom view, and FIG. 7C is a cross-sectional view.
[0071] In the glass substrate GO of the second embodiment of the
present invention, the marks which distinguish between the concave
surface G2A and convex surface G2B thereof include: two marks 230
and 240 formed on the concave surface G2A and differing from each
other in distance from the center of gravity on the concave surface
G2A, and two marks 210 and 220 which are formed on the convex
surface G2B in positions respectively facing the two marks 230 and
240 formed on the concave surface G2A and Which are equal in shape
to the respective corresponding marks 230 and 240 formed on the
concave surface G2A. It is preferable that a shortest line M by
which the two marks 210 and 220 on the convex surface G2B are
connected to each other on the convex surface G2B should not pass
through the center of gravity J on the convex surface G2B. In cases
where this requirement is satisfied, the concave surface G2A and
convex surface G2B of the glass substrate G2 can be distinguished
more reliably by the marks 210, 220, 230, and 240.
[0072] Methods for distinguishing the concave surface G2A and the
convex surface G2B from each other are explained here. It is
assumed that there are two marks 230 and 240 on the concave surface
G2A of the glass substrate G2 and that the two marks 230 and 240
respectively have different distances S and T from the center of
gravity K on the concave surface G2A, the mark 230 being closer to
the center of gravity K than the mark 240, as shown, for example,
in FIG. 7A and FIG. 7B. It is further assumed that the marks 210
and 220 are circular through-holes and that the mark 210 is
identical with the mark 230 and the mark 220 is identical with the
mark 240.
[0073] In FIG. 7A, in which the convex surface G2B is an upper
surface, a mark 220 is formed in a region ranging to less than
180.degree. counterclockwise from the mark 210 with respect to the
center of gravity J of the glass substrate G2 (.theta. in FIG. 7A
is less than 180.degree.). Thus, if the mark 220 lies in a region
(where .theta. is less than 180.degree.) ranging to less than
180.degree. counterclockwise from the mark 210 with respect to the
center of gravity J of the glass substrate G2, then this surface is
found to be a convex surface G2B. If the mark 220 lies in a region
(where .theta. is larger than 180.degree.) ranging to more than
180.degree. counterclockwise from the mark 210 with respect to the
center of gravity K of the glass substrate G2, as in FIG. 7B, then
this surface is found to be a concave surface G2A.
[0074] In case where a mirk 220 is formed at a position, where
.theta. is 180.degree., the concave surface G2A cannot be
distinguished from the convex surface G2B. In this case, a shortest
line by which the two marks 210 and 220 on the convex surface G2B
are connected to each other passes through the center of gravity J
on the convex surface G2B.
[0075] In the glass substrate G2 of the second embodiment of the
present invention, the shortest line by which the two marks 210 and
220 on the convex surface G2B are connected to each other on the
convex surface G2B does not pass through the center of gravity J on
the convex surface. hi cases where marks 210 and 220 are formed in
such positions, it is possible to distinguish the concave surface
G2A from the convex surface G2B.
[0076] The shortest line by which the two marks 210 and 220 on the
convex surface G2B are connected to each other on the convex
surface G2B does not pass preferably through a region ranging to 1
mm from the center of gravity T on the convex surface, more
preferably through a region ranging to 5 mm therefrom, even more
preferably through a region raving to 10 mm therefrom. The
positions of the marks 210 and 220 can be specified, for example,
by taking an image of the convex surface G2B of the glass substrate
G2 with a camera and analyzing the image.
[0077] Next, glass substrates according to a third embodiment of
the present invention are explained.
[0078] FIG. 8A to FIG. 8C and FIG. 9A to FIG. 9C show glass
substrates G3 of the third embodiment of the present invention;
FIG. 8A and FIG. 9A are top views, FIG. 8B and FIG. 9B are bottom
views, and FIG. 8C and FIG. 9C are cross-sectional views.
[0079] A glass substrate G3 of the third embodiment of the present
invention is one in which one or more marks that distinguish
between the concave surface G3A and the convex surface G3B are
marks formed on at least one of the concave surface G3A and the
convex surface G3B. It is preferable that the marks on the concave
surface G3A and the marks on the convex surface G3B have at least
one difference selected from the group consisting of number, shape,
and distance from the center of gravity.
[0080] In FIG. 8A to FIG. 8C, the concave surface G3A and the
convex surface G3B differ from each other in the number of marks
formed thereon. The expression "differ in the number of marks"
includes the case where either the concave surface G3A or the
convex surface G3B has no mark. FIG. 8A to FIG. 8C show a glass
substrate in which the concave surface G3A has a mark 310 formed
thereon and the convex surface G3B has no mark. In cases where
marks are formed so that the concave surface G3A and the convex
surface G3B differ from each other in the number of marks formed
thereon, there is an advantage in that so long as how many marks
are to be formed on each of the concave surface G3A and the convex
surface G3B is decided beforehand, the concave surface G3A and the
convex surface G3B can be distinguished from each other by counting
the marks donned on the concave surface G3A and the marks formed on
the convex surface G3B.
[0081] In FIG. 9A to FIG. 9C, the mark 330 formed on the concave
surface G3A and the mark 320 thrilled on the convex surface G3B
differ from each other in shape and in distance Q or P from the
center of gravity R or O. In cases where the mark 330 on the
concave surface G3A and the mark 320 on the convex surface G3B are
formed so as to differ in shape, there is an advantage in that so
long as what shape the mark to be formed on each of the concave
surface G3A and convex surface G3B has is decided beforehand, the
concave surface G3A and the convex surface G3B can be distinguished
from each other by determining the shape of the mark formed on the
concave surface G3A and the shape of the mark formed on the convex
surface G3B. In the case where at least one of the concave surface
G3A and the convex surface G3B has two or more marks, these marks
may be ones in which at least one of all the marks differs in shape
from the other marks,
[0082] Furthermore, in cases where the mark 330 on the concave
surface G3A and the mark 320 on the convex surface G3B are formed
so as to differ in distance Q or P from the center of gravity R or
O, there is an advantage in that so long as where the mark is
formed on each of the concave surface G3A and convex surface G3B is
decided beforehand, the concave surface G3A and the convex surface
G3B can be distinguished from each other by measuring the distances
Q and P from the centers of gravity R and O to the mark 330 formed
on the concave surface G3A and the mark 320 formed on the convex
surface G3B. In the case where at least one of the concave surface
G1A and the convex surface G3B has two or more marks, these marks
may be ones in which at least one of all the marks differs from the
other marks in distance to the center of gravity.
[0083] In the glass substrate according, to this embodiment
explained above, the concave surface and convex surface of the
glass substrate can be distinguished from each other. Sticking
(pasting) the glass substrate to a substrate containing silicon can
hence be performed so that the convex surface of the glass
substrate is recognized and stuck (pasted) to the substrate
containing silicon. Consequently, bubble inclusion is less apt to
occur between the glass substrate and the substrate containing
[0084] It is preferable that a glass substrate of one embodiment of
the present invention should has a depression as at least one of
the marks. In cases where a mark is constituted of a depression,
the position of the mark can be easily detected, and which main
surface of the glass substrate is the convex sur ace can be easily
determined. Depressions can be formed, for example, with a laser.
The depressions are not limited in shape, size, or number. The
depressions may have any shape such as, for example, a circle,
ellipse, or polygon, or may be letters or symbols.
[0085] In the case where a glass substrate of one embodiment of the
present invention has a depression as a mark, it is preferable that
the depression should have a depth of 1-50 .mu.m. In cases where
the depth of the depression is 1 .mu.m or larger, this depression
is easy to detect. The depth of the depression is more preferably 3
.mu.m or larger, even more preferably 4 .mu.m or larger. In cases
where the depth of the depression is 50 .mu.m or less, the glass
substrate is less apt to crack. The depth of the depression is more
preferably 20 .mu.m or less, even more preferably 10 .mu.m or
less.
[0086] The symbol "-" used above for indicating a numerical range
means that numerical values that precede and succeed the symbol are
included in the range as a lower limit and an upper limit, Unless
otherwise indicated, "-" has the same meaning in this
description.
[0087] It is preferable that one main surface of a glass substrate
of one embodiment of the present invention should have an area of
70-2,000 cm.sup.2. In cases where the glass substrate has an area
of 70 cm.sup.2 or larger, a substrate containing silicon which
includes a large number of silicon elements can be disposed and an
improvement in production efficiency is attained in a step of
laminating the glass substrate with a substrate containing silicon.
The area of the one main surface of the glass substrate is more
preferably 80 cm.sup.2 or larger, even more preferably 170 cm.sup.2
or larger, especially preferably 300 cm.sup.2 or larger, most
preferably 700 cm.sup.2 or larger. In cases where the area of the
one main surface of the glass substrate is 2,000 cm.sup.2 or less,
this glass substrate is easy to handle and can be inhibited from
being damaged by contact with the substrate containing silicon or
with peripheral members, etc. The area of the one main surface is
more preferably 1,700 cm.sup.2 or less, even more preferably 1,000
cm.sup.2 or less, especially preferably 800 cm.sup.2 or less, most
preferably 750 cm.sup.2 or less.
[0088] It is preferable that a glass substrate of one embodiment of
the present invention should be circular. In cases where the glass
substrate is circular, it is easy to laminate this glass substrate
with a substrate containing silicon. In particular, laminating with
a circular substrate containing; silicon is easy. The term
"circular" means a shape that is not limited to a complete circle
and that may be a circle in which the dimensional deviations from a
complete circle having the same diameter are up to 50 .mu.m.
[0089] In the case where a glass substrate of one embodiment of the
present invention is circular, it is preferable that a diameter
thereof should be 7 cm or larger. In cases where the diameter
thereof is 7 cm or larger, a substrate containing silicon which
includes a large number of silicon elements can be disposed.
Furthermore, a large number of semiconductor elements can be
obtained from the laminated substrate formed by sticking the glass
substrate having a diameter of 7 cm or larger to the substrate
containing silicon resulting in an improvement in production
efficiency. The diameter thereof is more preferably 10 cm or
larger, even more preferably 15 cm or larger, especially preferably
20 cm or larger, most preferably 25 cm or larger.
[0090] It is preferable that the diameter thereof should be 50 cm
or less. In cases where the diameter thereof is 50 cm or less, this
glass substrate is easy to handle and can be inhibited from being
damaged by contact with the substrate containing silicon or with
peripheral members, etc. The diameter thereof is more preferably 45
cm or less, even more preferably 40 cm or less, especially
preferably 35 cm or less.
[0091] The shape of a glass substrate of one embodiment of the
present invention is not limited to a circular shape and may be
rectangular, In the case of a circular shape, a part of a periphery
thereof may be straight. In cases where the glass substrate is
rectangular, a larger number of semiconductor elements can be
obtained from the laminated substrate formed by sticking this glass
substrate to a substrate containing silicon, as compared with the
case of a circular glass substrate having the same area, resulting
in an improvement in production efficiency.
[0092] It is preferable that a glass substrate of one embodiment of
the present invention should have a thickness of 2.0 mm or less. In
cases where the thickness thereof is 2.0 mm or less, the laminated
substrate obtained by sticking this glass substrate to a substrate
containing silicon can have a reduced thickness. The thickness of
the glass substrate is more preferably 1.5 mm or less, even more
preferably 1.0 mm or less, especially preferably 0.8 mm or
less.
[0093] It is preferable that the thickness thereof should be 0.1 mm
or larger. In cases where the thickness thereof is 0.1 mm or
larger, this glass substrate can be inhibited from being damaged by
contact with the substrate containing silicon or with peripheral
members, etc. Furthermore, this glass substrate can be inhibited
from bending due to its own weight. The thickness thereof is more
preferably 0.2 mm or larger, even more preferably 0.3 mm or
larger.
[0094] It is preferable that a glass substrate of one embodiment of
the present invention should have a deviation of plate thickness of
15 .mu.m or less. The deviation of plate thickness is calculated
through a thickness measurement with, for example, a laser
displacement meter. In cases where the deviation of plate thickness
is 15 .mu.m or less, a sticking surface to a substrate containing
silicon has satisfactory conformability, making it easy to laminate
this glass substrate with the substrate containing silicon. The
deviation of plate thickness is more preferably 12 .mu.m or less,
even more preferably 10 .mu.m or less, especially preferably 5
.mu.m or less.
[0095] It is preferable that a glass substrate of one embodiment of
the present invention should have a Young's modulus of 65 GPa or
higher. The Young's modulus is measured, for example, by an
ultrasonic pulse method, In cases where the Young's modulus thereof
is 65 GPa or higher, the glass substrate warpage or cracking which
may occur in the slow cooling step performed when producing the
glass substrate can be inhibited. Furthermore, this glass substrate
can be inhibited from being damaged by contact with the substrate
containing silicon, etc. The Young's modulus thereof is more
preferably 70 GPa or higher, even more preferably 75 GPa or higher,
especially preferably 80 GPa or higher.
[0096] It is preferable that the Young's modulus thereof should be
100 GPa or less. In. cases where the Young's modulus thereof is 100
GPa or less, this glass can be inhibited from being brittle and the
glass substrate can be inhibited from chipping When being processed
by cutting or dicing. The Young's modulus thereof is more
preferably 90 GPa or less, even more preferably 87 GPa or less.
[0097] It is preferable that a glass substrate of one embodiment of
the present invention should have an average coefficient of thermal
expansion at 50.degree. C.-350.degree. C. of 30-140
(.times.10.sup.-7/.degree. C. A heat treatment step is necessary
for sticking a substrate containing silicon to the glass
substrate.
[0098] In the heat treatment step, for example, the substrate
containing silicon and the glass substrate are stuck to each other
at a temperature of 200.degree. C.-400.degree. C., and the
resultant laminated substrate is cooled to room temperature. In
case where there is a difference in the coefficient of thermal
expansion between the glass substrate and the substrate containing
silicon, the difference in the coefficient of thermal expansion is
causative of the generation of a large residual strain (residual
deformation) in the substrate containing silicon.
[0099] In cases where the average coefficient of thermal expansion
at 50.degree. C.-350.degree. C. is 30-140
(.times.10.sup.-7/.degree. C.), the residual strain which generates
in the substrate containing silicon in the heat treatment step for
sticking the substrate containing silicon to the glass substrate is
small.
[0100] The average coefficient of thermal expansion at 50.degree.
C.-350.degree. C. is determined through a measurement of thermal
expansion coefficient made in the temperature range of 50.degree.
C.-350.degree. C. by the method as provided for in JIS R3102 (year
1995).
[0101] In the case where a glass substrate of one embodiment of the
present invention used as a fan-out type wafer-level package, a
substrate containing silicon is laminated over the glass substrate
and a resin is formed so as to be in contact with both the glass
substrate and the substrate containing In cases where the glass
substrate has an average coefficient of thermal expansion at
50.degree. C.-350.degree. C. of 30-50 (.times.10.sup.-7/.degree.
C.), the residual strain which generates in the substrate
containing silicon in the heat treatment step is small.
[0102] The average coefficient of thermal expansion at 50.degree.
C.-350.degree. C. may be 31-50 (.times.10.sup.-7/.degree. C.), or
may be 32-40 (.times.10.sup.-7/.degree. C.), or may be 32-36
(.times.10.sup.-7/.degree. C.), or may be 34-36
(.times.10.sup.-7/.degree. C.).
[0103] Meanwhile, in cases where the average coefficient of thermal
expansion at 50.degree. C.-350.degree. C. is 50-80
(.times.10.sup.-7/.degree. C.), the residual strain which generates
in the substrate containing silicon and the resin in the heat
treatment step is small.
[0104] The average coefficient of thermal expansion at 50.degree.
C.-350.degree. C. may be 60-75 (.times.10.sup.-7/.degree. C.), or
may be 67-72 (.times.10.sup.-7/.degree. C.).
[0105] Meanwhile, in cases where the average coefficient of thermal
expansion at 50.degree. C.-350.degree. C. is 80-120
(.times.10.sup.-7/.degree. C.), the residual strain which generates
in the resin and the wiring is small. The average coefficient of
thermal expansion at 50.degree. C.-350.degree. C. may be 85-100
(.times.10.sup.-7/.degree. C.), or may be 90-95
(.times.10.sup.-7/.degree. C.).
[0106] In cases where the average coefficient of thermal expansion
at 50.degree. C. -350.degree. C. is 120-140
(.times.10.sup.-7/.degree. C.), the residual strain which generates
in the substrates of fan-out type wafer-level packages that have a
high resin proportion and a high average coefficient of thermal
expansion is small.
[0107] The average coefficient of thermal expansion at 50.degree.
C.-350.degree. C. may be 120-135 (.times.10.sup.-7/.degree. C.), or
may be 125-130 (.times.10.sup.-7/.degree. C.).
[0108] It is preferable that a glass substrate of one embodiment of
the present invention should include a light-shielding film
thrilled on at least one of the concave surface and convex surface
of the glass substrate. In cases where the glass substrate includes
a light-shielding film formed on at least one of the concave
surface and convex surface thereof, it is easy to detect the
position of the glass substrate or laminated substrate in the
inspection step of the glass substrate or laminated substrate. The
position thereof is specified on the basis of reflected light
caused by irradiating the glass substrate or the laminated
substrate with light. Glass substrates are prone to transmit light.
By forming a light-shielding film on a main surface of the glass
substrate. the reflected light is intensified to facilitate the
detection of the position. It is preferable that the
light-shielding film should include Ti.
[0109] It is preferable that a glass substrate of one embodiment of
the present invention should contain 0-0.1% of an alkali metal
oxide, as represented by mole percentage based on oxides. Examples
of the alkali metal oxides include Li.sub.2O, Na.sub.2O, and
K.sub.2O. In cases where the content of alkali metal oxides is 0.1%
or less as represented by mole percentage based on oxides, alkali
ions are less apt to diffuse in the substrate containing silicon in
the heat treatment step in which the silicon substrate is stuck to
the glass substrate.
[0110] The content of alkali metal oxides as represented by mole
percentage based on oxides is more preferably 0.05% or less, even
more preferably 0.02% or less. It is especially preferable that the
glass substrate should contain substantially no alkali metal
oxides. The expression "contain substantially no alkali metal
oxides" means that the glass substrate contains completely no
alkali metal oxides or that the glass substrate may contain alkali
metal oxides as impurities which have come thereinto unavoidably
because of the production process.
[0111] It is preferable that a glass substrate of one embodiment of
the present invention should have a density of 2.60 g/cm.sup.3 or
less. In cases where the density thereof is 2.60 g/cm.sup.3 or
less, this glass substrate is lightweight. This glass substrate is
less apt to suffer bending due to its own weight. The density
thereof is more preferably 2.55 g/cm.sup.3 or less, even more
preferably 2.50 g/cm.sup.3 or less.
[0112] It is preferable that the density thereof should be 2.20
g/cm.sup.3 or higher. In cases where the density thereof is 2.20
g/cm.sup.3 or higher, this glass has an increased Vickers hardness
and the glass surfaces are less apt to receive scratches. The
density thereof is more preferably 2.30 g/cm.sup.3 or higher, even
more preferably 2.40 g/cm.sup.3 or higher, especially preferably
2.45 g/cm.sup.3 or higher.
[0113] It is preferable that a glass substrate of one embodiment of
the present invention should have a transmittance at wavelength of
250 nm of 10% or higher. By irradiating the resin with ultraviolet
light through the glass substrate, the glass substrate is removed
from the laminated substrate. In cases where the glass substrate
has a transmittance at wavelength of 250 nm of 10% or higher, the
resin is irradiated with a larger amount of ultraviolet light,
easily rendering the glass substrate removable from the laminated
substrate. The transmittance at wavelength of 250 nm is more
preferably 15% or higher, even more preferably 20% or higher.
[0114] It is preferable that a glass substrate of one embodiment of
the present invention should have a transmittance at wavelength of
300 nm of 45% or higher. In cases where the glass substrate has a
transmittance at wavelength of 300 nm of 45% or higher, the resin
is irradiated with a larger amount of ultraviolet light, easily
rendering the glass substrate removable from the laminated
substrate. The transmittance at wavelength of 300 nm is more
preferably 50% or higher, even more preferably 55% or higher,
especially preferably. 60% or higher.
[0115] It is preferable that a glass substrate of one embodiment of
the present invention should have a transmittance at wavelength of
350 nm of 45% or higher. In cases where the glass substrate has a
transmittance at wavelength of 350 nm of 45% or higher, the resin
is irradiated with a larger amount of ultraviolet light, easily
rendering the glass substrate removable from the laminated
substrate. The transmittance at wavelength of 350 nm is more
preferably 50% or higher, even more preferably 55% or higher,
especially preferably 60% or higher.
[0116] It is preferable that a glass substrate of one embodiment of
the present invention should be one in which an amount of defects
having a major-axis length of 200 .mu.m or larger, such as bubbles
and foreign matter, is 10 pcs/cm.sup.2 or less. In cases where the
amount of defects having a major-axis length of 200 .mu.m or larger
therein is 10 pcs/cm.sup.2 or less, the light used for irradiation
in the sticking step is less blocked and the sticking is easy. The
amount of defects having a major-axis length of 200 .mu.m or larger
therein is more preferably 2 pcs/cm.sup.2 or less. It is especially
preferable that the glass substrate should contain no defects
having a major-axis length of 200 .mu.m or larger.
[0117] It is preferable that a glass substrate of one embodiment of
the present invention should be used in such a manner that the
convex surface of the glass substrate is stuck to a substrate
containing silicon to thereby form a laminated substrate. In cases
where a laminated substrate is formed in this manner, bubble
inclusion is less apt to occur between the glass substrate and the
substrate containing silicon in sticking the glass substrate to the
substrate containing silicon. In cases where the laminated
substrate is stored and transported so that the concave surface of
the glass substrate is supported by supporting members, the
laminated substrate is less apt to deform.
[0118] The supporting members are not limited to a fixed type, and
may be of a movable type. By supporting the glass substrate and the
laminated substrate by movable fixing members, the glass substrate
and the laminated substrate can be transported without
contaminating the surfaces of the glass substrate and laminated
substrate. Furthermore, by supporting the concave surfaces of the
glass substrate and laminated substrate by movable supporting
members, the glass substrate or the laminated substrate can be
transported while inhibiting the deformation thereof.
[0119] Next, a laminated substrate according to one embodiment of
the present invention is explained.
[0120] The laminated substrate of one embodiment of the present
invention is firmed by sticking (pasting) the convex surface of the
glass substrate to a substrate containing silicon. Since this
laminated substrate is formed by sticking (pasting) the convex
surface of the glass substrate to a substrate containing silicon,
bubble inclusion is less apt to occur between the glass substrate
and the substrate containing
[0121] Subsequently, a laminated substrate according to another
embodiment of the present invention is explained.
[0122] The laminated substrate of another embodiment of the present
invention is a laminated substrate in which a curved surface
constituted of the convex surface or concave surface of the glass
substrate and a curved surface constituted of a convex surface or
concave surface of a substrate containing silicon are stuck
(pasted) to each other so as to conform to each other. The
expression "conform to each other" means that the curved surface of
the glass substrate and the curved surface of the substrate
containing silicon face in the same direction, that is, the two
substrates are equal in warpage direction.
[0123] FIG. 12A and FIG. 12B is cross-sectional views for
illustrating relationships between a curved surface of a glass
substrate and a curved surface of a substrate containing silicon in
a step for producing, a laminated substrate.
[0124] In the embodiment shown in FIG. 12A, the curved surface
constituted of the convex surface of a glass substrate G1 and the
curved surface constituted of the concave surface of a substrate
containing silicon 10 are stuck to each other so as to conform to
each other. It is hence possible to attain a reduction in the
unevenness of adhesion between the glass substrate G1 and the
substrate containing silicon 10, an improvement in bubble
elimination during the sticking, a reduction in the degree of
overall warpage, a reduction in interlaminar residual stress, and
an even distribution of interfacial residual stress in the cured
laminated substrate, resulting in improvements in yield and
reliability. In addition, not only a decrease in yield due to, for
example, an interfacial separation failure in a later step can be
prevented but also chip products produced through a dicing process
in a final step have improved reliability.
[0125] In contrast, FIG. 12B shows a configuration in which a glass
substrate G1 and a substrate containing silicon 10 are stuck to
each other so that the concave surfaces thereof face each other. In
this configuration, the laminated substrate has an uneven
distribution of interfacial residual stress, and portions having
high residual stress are locally and scatteringly present therein.
Such unevenness not only undesirably induces a separation failure
but also results in unevenness in reliability among the chip
products.
[0126] It is hence preferable that a process for producing a
laminated substrate of the present invention should include
sticking a curved surface constituted of the convex surface or
concave surface of a glass substrate G1 to a curved surface
constituted of the convex surface or concave surface of a substrate
containing silicon 10 so that the curved surfaces of the two
substrates conform to each other.
[0127] In the laminated substrate of the present invention, a
difference in warpage between the glass substrate G1 and the
substrate containing silicon 10, i.e., a maximum dimension, along a
direction perpendicular to a substrate plane directions, of any
space Banned between the glass substrate it and the substrate
containing silicon 10 which have been laminated, is preferably
0-400 .mu.m, more preferably 0-100 .mu.m. So long as the warpage
difference is within that range, the effects shown above can be
satisfactorily produced.
[0128] In the laminated substrate of the present invention, it is
preferable that the glass substrate G1 should be one formed by a
float process. Glass substrates formed by the float process are apt
to have a warped shape which is a bowl shape symmetrical with
respect to the center, and are apt to be even in conformation
direction during sticking, as compared with glass substrates formed
by a fusion process, which is prone to result in random warped
shapes, e.g., a saddle shape. Use of a glass substrate formed by
the float process is hence apt to contribute to quality
stabilization. In the case where a glass substrate formed by the
fusion process is deemed to be "free from waviness" in accordance
with the SEMI standards as described above, this glass substrate
can be satisfactorily used.
[0129] It is more preferable that the process for producing a
laminated substrate of the present invention should include
predicting the shape of the curved surface of the substrate
containing silicon beforehand, and sticking this curved surface and
the curved surface of the glass substrate to each other so that the
predicted shape of the curved surface and the shape of the curved
surface of the glass substrate conform to each other. For example,
in the production of a fan-out type wafer-level package or the
like, the package is a hybrid including a substrate containing
silicon and another material, e.g., a resin, and the direction of
warpage is frequently determined, depending on products, as the
production process proceeds. Consequently, in cases where what
warped shape the substrate containing silicon forms in a production
process is predicted beforehand and the substrate containing
silicon and the glass substrate are stuck to each other so that the
predicted warped shape and the warped shape of the glass substrate
conform to each other, then the residual stress remaining at the
sticking interface after the production process can be made even or
be reduced.
[0130] It is preferable that a laminated substrate of one
embodiment of the present invention should have a thickness of
0.5-3 mm. In cases where the thickness thereof is 0.5 mm or larger,
this laminated substrate has increased strength and can be
inhibited from being damaged by contact with peripheral members,
etc. The thickness thereof is more preferably 1.0 mm or larger,
even more preferably 1.3 mm or larger. In cases where the thickness
thereof is 3 mm or less, this laminated substrate can be thin. The
thickness thereof is more preferably 25 mm or less, even more
preferably 20 mm or less.
[0131] In a laminated substrate of one embodiment of the present
invention, the substrate containing silicon may have a cutout
formed therein, In cases where the substrate containing silicon has
a cutout, the position and angle of the substrate containing
silicon can be specified on the basis of the cutout when forming
circuit patterns on the substrate containing silicon. Thus, the
circuit patterns can be inhibited from suffering a dimensional
dislocation, The position of the cutout in the substrate containing
silicon can be detected, for example, with a laser. The cutout may
be detected by taking an image of the glass substrate with a camera
and analyzing the image.
[0132] It is preferable that a laminated substrate of one
embodiment of the present invention should be one in which the
glass substrate and the substrate containing silicon each have
cutouts and which has been formed by sticking the glass substrate
to the substrate containing silicon so that the cutout of the glass
substrate and the cutout of the substrate containing silicon lie in
the same position. In cases where the laminated substrate has been
thus formed, it is easy to detect the position of the cutout of the
substrate containing silicon and to inhibit circuit patterns from
suffering a dimensional dislocation,
[0133] For example, the cutouts can be detected by irradiating,
either the substrate containing silicon or the glass substrate with
a laser. In cases where the cutouts are notches, the glass
substrate and the silicon substrate have a small area loss, and the
glass substrate and the substrate containing silicon are apt to be
easily stuck to each other. Furthermore, since the substrate
containing silicon has a small area loss, a large number of
circuits can be formed on the substrate containing silicon. In
cases where the cutouts are OFs, the cutouts can be easily formed
and the positions of the cutouts are easy to detect.
[0134] A laminated substrate of one embodiment of the present
invention may be one formed by sticking the concave surface of the
glass substrate as a component of one laminated substrate to the
substrate containing silicon as a component of another laminated
substrate. Two laminated substrates may have been stuck to each
other, or three laminated substrates may have been stuck together,
or four laminated substrates may have been stuck together. The
laminated substrate thus formed is less apt to have residual stress
and to suffer cracking or chipping.
[0135] It is preferable that a laminated substrate of one
embodiment of the present invention should be supported by
supporting the concave surface of the glass substrate at four
points by supporting members. In cases where the concave surface of
the glass substrate is supported at four points by supporting
members, the surface of the glass substrate or laminated substrate
is less apt to be contaminated with dust, etc.
[0136] A laminated substrate of one embodiment of the present
invention may be supported by supporting the concave surface of the
glass substrate at two sides by supporting members. In cases where
the concave surface of the glass substrate is supported at two
sides by supporting members, the laminated substrate can be stably
stored and transported. Furthermore, the surface of the laminated
substrate is less apt to be contaminated with dust, etc.
[0137] Next, laminates according to embodiments of the present
invention are explained.
[0138] A laminate of one embodiment of the present invention is
characterized by being formed by sticking (pasting) another glass
substrate to the glass substrate which is a component of the
laminated substrate. In the case where a laminated substrate of one
embodiment of the present invention is used as a support glass for
semiconductor back grinding, it is necessary, for regulating the
thickness of the glass substrate, to wind the glass substrate since
this glass substrate is the only one glass substrate contained as a
component of the laminated substrate.
[0139] Since the laminate of one embodiment of the present
invention has been formed by sticking another glass substrate to
the glass substrate which is a component of the laminated
substrate, thickness regulation can be attained, without
necessitating grinding of the glass substrate, by removing the
other glass substrate. Meanwhile, a glass substrate having any
thickness has a deflection amount larger than the deflection amount
of a laminated substrate obtained by sticking two glass substrates
each having a thickness one-half the thickness of said glass
substrate. By regulating the thickness of each glass substrate and
the number of glass substrates to be laminated together, the
deflection amount of the laminated substrate can be regulated.
[0140] Next, packages according to embodiments of the present
invention are explained.
[0141] FIG. 10 is a cross-sectional view of a package 500 according
to one embodiment of the present invention, The package 500 of one
embodiment of the present invention is formed by packaging two or
more glass substrates which each are the glass substrate described
above, so that the convex surface G5B of one glass substrate G5 of
these glass substrates faces the concave surface G6A of another
glass substrate G6.
[0142] FIG. 11 is a cross-sectional view of a package 600 according
to one embodiment of the present invention. The package 600 of one
embodiment of the present invention is formed by packaging two or
more laminated substrates which each are the laminated substrate
described above, so that the substrate containing silicon 640 which
is a component of one laminated substrate 610 of these laminated
substrates faces the concave surface G8A of the glass substrate G8
which is a component of another laminated substrate 620.
[0143] A package according to one embodiment of the present
invention is formed by packaging two or more laminates which each
are the laminate described above, so that the substrate containing
silicon as a component of one of these laminates faces the concave
surface of the glass substrate as a component of another
laminate.
[0144] In a package according to one embodiment of the present
invention, the number of the glass substrates, laminated
substrates, or laminates used for forming the package may be either
2 or 3, and may be any number not less than 2. In the package thus
formed, the convex surfaces or concave surfaces of the glass
substrates face in the same direction and, hence, the spaces
between the glass substrates, laminated substrates, or laminates of
which the package is configured can be narrowed. Hence, the package
can have a reduced size.
[0145] As a result, such a package in which the convex surfaces or
concave surfaces of the glass substrates face in the same direction
can contain a larger number of laminated substrates than a package
of the same size in which the convex surfaces or concave surfaces
of the glass substrates do not face in the same direction.
[0146] In the case where such glass substrates, laminated
substrates, or laminates are to be transported while being
supported, for example, by movable supporting members, it is easy
to make the concave surfaces of the glass substrates supported by
the supporting members, since the convex surfaces or concave
surfaces of the glass substrates face in the same direction. Thus,
the laminated substrates can be transported while inhibiting the
glass substrates, laminated substrates, or laminates from deform.
Furthermore, since the convex surfaces or concave surfaces of the
glass substrates face in the same direction, the surfaces of the
substrate containing silicon on which deposition is to be performed
can be made flush with each other. Thus, it is easy to control the
distribution of the thickness of the film to be deposited.
[0147] It is preferable that a package according to one embodiment
of the present invention should be one in which the concave surface
of each glass substrate is supported at four points by supporting
members. In cases where the concave surface of each glass substrate
is supported at four points by supporting members, the surface of
each glass substrate or laminated substrate is less apt to be
contaminated with dust, etc.
[0148] A package according to one embodiment of the present
invention may be housed in a container. In cases where the package
is housed in a container, the package is less apt to be
contaminated with dust, etc.
[0149] Next, a process for producing a glass substrate of one
embodiment of the present invention is explained.
[0150] In the case of producing the glass substrate of one
embodiment of the present invention, the process includes a step of
melting, refining, forming, slow cooling, cutting, inspection, and
marking.
[0151] In the melting step, raw materials are prepared so as to
yield a glass substrate having a desired composition, and the raw
materials are continuously introduced into a melting furnace and
heated to preferably about 1,400-1,650.degree. C., thereby
obtaining a molten glass.
[0152] In the refining step, SO.sub.3 or SnO.sub.2 can be used as a
refining agent for the glass substrate according to the present
invention. A method of degassing under reduced pressure may be
applied.
[0153] To the forming step is applied a float process in which the
molten glass is poured onto a molten metal to obtain a plate-shaped
glass ribbon.
[0154] In the slow cooling step, the glass ribbon is slowly
cooled.
[0155] In the cutting step, glass plates are cut out of the glass
ribbon and then cut into a given shape of a given size, thereby
obtaining a glass substrate of one embodiment of the present
invention.
[0156] In the process for producing a glass substrate of one
embodiment of the present invention, for example, warpage is prone
to occur when a difference in temperature between one main surface
and the other main surface of the glass ribbon is large in the
forming step and the ling step.
[0157] In the inspection step, whether one main surface of the
glass substrate is a concave surface or a convex surface is
determined with, for example, a laser displacement meter.
[0158] In the step of placing a mark, one or more marks are placed
on at least one of the concave surface and convex surface of the
glass substrate. Depressions are formed, for example, with a laser.
By laser scanning, depressions of a desired shape are formed.
Letters or symbols may be formed. Notches or OFs may be formed, for
example, by forming cut lines with a cutter or a laser, followed by
fracturing.
[0159] The marks formed on the glass substrate are detected, for
example, by taking an image of the glass substrate with a camera
and analyzing the image. Thus, the concave surface and convex
surface of the glass substrate are distinguished from each
other.
[0160] In the case of producing a glass substrate of one embodiment
of the present invention, the molten glass may be formed into a
plate shape by applying a fusion process, a roll-out method, a
press forming, or the like in the forming step.
[0161] In the case of producing a glass substrate of one embodiment
of the present invention, a platinum crucible may be used. In the
case of using a platinum crucible, the melting step is performed in
the following manner. Raw materials are prepared so as to yield a
glass substrate having a given composition, and the platinum
crucible containing the raw materials is introduced into an
electric furnace. The raw materials are heated to preferably about
1,450-1,650.degree. C., and a platinum stirrer is inserted
thereinto to stir the contents for 1-3 hours, thereby obtaining a
molten glass.
[0162] In the refining step, SO.sub.3 or SnO.sub.2 can be used as a
fining agent. A method of degassing under reduced pressure may be
applied. As a refining agent for use in the method of degassing
under reduced pressure, it is preferred to use a halogen such as Cl
or F. In the forming step, the molten glass is poured, for example,
onto a carbon plate to forma platy glass, In the slow cooling step,
the platy ,glass is gradually cooled to a room-temperature state.
The platy glass is cut to obtain a glass substrate.
[0163] Although the present invention has been described in detail
with reference to specific embodiments thereof the invention is not
limited to the embodiments and various changes and modifications
can be made therein without departing from the spirit and scope
thereof. This application is based on a Japanese patent application
filed on Jul. 24, 2015 (Application No. 2015-147249) and a Japanese
patent application filed on Dec. 28, 2015 (Application No.
2015-256895), the entire contents thereof being incorporated herein
by reference. All the matters cited in these patent applications
are incorporated as references into the present application.
DESCRIPTION OF REFERENCE NUMERALS AND SIGN
[0164] 10 Substrate containing silicon
[0165] 20 Resin
[0166] 30 Laminated substrate
[0167] G1 Glass substrate
* * * * *