U.S. patent application number 15/013241 was filed with the patent office on 2016-06-02 for etch back processes of bonding material for the manufacture of through-glass vias.
The applicant listed for this patent is CORNING INCORPORATED. Invention is credited to Chih-Wei Tsai, Bor Kai Wang.
Application Number | 20160155696 15/013241 |
Document ID | / |
Family ID | 53177892 |
Filed Date | 2016-06-02 |
United States Patent
Application |
20160155696 |
Kind Code |
A1 |
Tsai; Chih-Wei ; et
al. |
June 2, 2016 |
ETCH BACK PROCESSES OF BONDING MATERIAL FOR THE MANUFACTURE OF
THROUGH-GLASS VIAS
Abstract
A method for manufacturing vias in a glass substrate includes
bonding, through a bonding layer, a first face of the glass
substrate including a plurality of holes to a first face of a glass
carrier. The bonding layer has a thickness t between the first face
of the glass substrate and the first face of the glass carrier and
extends into at least some of the plurality of holes to a depth h
from the first face of the glass substrate. The method includes
etching back the bonding layer to a depth d through the plurality
of holes in the glass substrate. The depth d is less than the sum
of the thickness t and the depth h. The method can include filling
the plurality of holes with an electrically conductive material,
and de-bonding the glass substrate from the bonding layer and the
glass carrier.
Inventors: |
Tsai; Chih-Wei; (Taipei
City, TW) ; Wang; Bor Kai; (New Taipei City,
TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CORNING INCORPORATED |
CORNING |
NY |
US |
|
|
Family ID: |
53177892 |
Appl. No.: |
15/013241 |
Filed: |
February 2, 2016 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
14699393 |
Apr 29, 2015 |
9263300 |
|
|
15013241 |
|
|
|
|
61986370 |
Apr 30, 2014 |
|
|
|
Current U.S.
Class: |
174/257 ;
174/258; 174/264 |
Current CPC
Class: |
H01L 2924/0002 20130101;
H01L 23/15 20130101; H01L 2221/68345 20130101; H01L 2924/00
20130101; H01L 2221/68381 20130101; H01L 23/49894 20130101; H01L
2924/0002 20130101; H01L 23/49866 20130101; C03C 15/00 20130101;
H01L 2221/68318 20130101; H01L 23/49838 20130101; H01L 23/49827
20130101; H01L 2221/68359 20130101; H01L 21/486 20130101; H01L
21/6835 20130101 |
International
Class: |
H01L 23/498 20060101
H01L023/498; H01L 21/683 20060101 H01L021/683 |
Claims
1-20. (canceled)
21. An assembly comprising: a substrate having a first face and a
second face; a carrier; a bonding layer positioned between the
first face of the substrate and a face of the carrier to bond the
substrate and carrier; a plurality of vias extending through the
substrate from the first face of the substrate to the second face
of the substrate and into at least a portion of the bonding
layer.
22. The assembly of claim 21, wherein the bonding layer is capable
of being de-bonded from the substrate.
23. The assembly of claim 22, wherein the bonding layer is an
ultraviolet curable adhesive.
24. The assembly of claim 21, wherein the vias are filled with an
electrically conductive material.
25. The assembly of claim 24, wherein the electrically conductive
material is selected from a group consisting of copper, silver,
aluminum, nickel, alloys thereof, and combinations thereof.
26. The assembly of claim 24, wherein the electrically conductive
material comprises copper-containing material.
27. The assembly of claim 21, wherein the plurality of vias extend
through an entire thickness of the bonding layer.
28. The assembly of claim 21, wherein the plurality of vias extend
through less than an entire thickness of the bonding layer.
29. The assembly of claim 21, wherein the substrate is glass.
30. The assembly of claim 21, wherein the carrier is glass.
31. The assembly of claim 21, wherein each of the plurality of vias
is pillar-shaped.
32. The assembly of claim 21, wherein each of the plurality of vias
is mushroom-shaped.
33. The assembly of claim 21, wherein the substrate has a thickness
of less than or equal to 100 um.
Description
[0001] This application is a continuation of U.S. patent
application Ser. No. 14/699,393 filed on Apr. 29, 2015, which
claims the benefit of priority under 35 U.S.C. .sctn. 119 of U.S.
Provisional Application Ser. No. 61/986,370 filed on Apr. 30, 2014,
the content of each is relied upon and incorporated herein by
reference in its entirety.
BACKGROUND
[0002] 1. Field
[0003] The present specification generally relates to the
manufacture of through glass vias and, more specifically, to
etching processes used to manufacture through glass vias.
[0004] 2. Technical Background
[0005] Through-substrate vias provide electrical connections
between layers in a physical electronic circuit or chip. For
example, in a three-dimensional stacked integrated circuit, the
through-substrate vias enable integration of electronic components
both vertically and horizontally. Conventionally, through-substrate
vias employ a silicon substrate. However, because glass is less
expensive than silicon, glass substrates are becoming more
prevalent in electronic devices.
[0006] While a reduced cost, a flexible coefficient of thermal
expansion, and the inherent insulation properties of glass make the
choice of glass as a substrate an attractive option, the use of
glass presents several challenges. In particular, one challenge of
using a glass substrate is the handling of a suitably thin piece of
glass during the manufacturing process. Another challenge is
forming holes in a glass substrate at a high rate of speed without
cracking the glass at the entrance holes and without adversely
affecting metallization of the vias.
[0007] Accordingly, a need exists for alternative methods for
forming through-glass vias which enhance manufacturability and
achieve reliable metallization of the vias.
SUMMARY
[0008] According to one embodiment, a method for manufacturing a
plurality of vias in a substrate includes bonding a first face of
the substrate including a plurality of holes to a first face of a
carrier using a bonding layer. The bonding layer has a thickness t
between the first face of the substrate and the first face of the
carrier and extends into at least some of the plurality of holes to
a depth h from the first face of the glass substrate. The method
also includes etching the bonding layer to a depth d through the
plurality of holes in the substrate. The depth d is less than the
sum of the thickness t and the depth h. The method also includes
filling the plurality of holes with a material to form the
plurality of vias.
[0009] In another embodiment, a method for manufacturing a
plurality of vias in a substrate includes bonding a first face of
the gsubstrate including a plurality of holes to a first face of a
carrier, etching the bonding layer to a depth d through the
plurality of holes in the substrate using a wet etch process,
filling the plurality of holes with an electrically conductive
material to form the plurality of vias in the substrate, and
de-bonding the glass substrate including the plurality of vias from
the bonding layer and the carrier. The first face of the substrate
is bonded to the glass carrier through a bonding layer. The bonding
layer has a thickness t between the first face of the substrate and
the first face of the carrier, and the depth d is measured from the
first face of the substrate. The depth d is less than the thickness
t. The electrically conductive material extends into the bonding
layer by the depth d such that when the substrate is de-bonded from
the bonding layer and the carrier, the electrically conductive
material protrudes from the first face of the substrate.
[0010] In another embodiment, a method for manufacturing a
plurality of vias in a substrate includes bonding a first face of
the substrate including a plurality of holes to a first face of a
carrier through a bonding layer, etching the bonding layer to a
depth d using a dry etch process, filling the plurality of holes
with an electrically conductive material to form the plurality of
vias in the substrate, and de-bonding the substrate including the
plurality of vias from the bonding layer and the carrier. The
bonding layer has a thickness t between the first face of the
substrate and the first face of the carrier. The depth d is
measured from the first face of the substrate and is equal to the
thickness t. The first face of the carrier is a stop layer for the
dry etch process. When the substrate is de-bonded from the bonding
layer and the carrier, the electrically conductive material forms
pillars extending from the first face of the substrate a length l,
wherein the length l is equal to the thickness t of the bonding
layer.
[0011] Additional features and advantages will be set forth in the
detailed description which follows, and in part will be readily
apparent to those skilled in the art from that description or
recognized by practicing the embodiments described herein,
including the detailed description which follows, the claims, as
well as the appended drawings.
[0012] It is to be understood that both the foregoing general
description and the following detailed description describe various
embodiments and are intended to provide an overview or framework
for understanding the nature and character of the claimed subject
matter. The accompanying drawings are included to provide a further
understanding of the various embodiments, and are incorporated into
and constitute a part of this specification. The drawings
illustrate the various embodiments described herein, and together
with the description serve to explain the principles and operations
of the claimed subject matter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 schematically depicts a glass substrate including a
plurality of holes bonded to a glass carrier through a bonding
layer in accordance with one or more embodiments;
[0014] FIG. 2 schematically depicts a cross-section of a process of
etching back the bonding layer through the plurality of holes in
the glass substrate depicted in FIG. 1 in accordance with one or
more embodiments;
[0015] FIG. 3A schematically depicts a cross-section of a process
of etching back the bonding layer to a depth d that is equal to a
height h of a distal face of the bonding layer within the plurality
of holes in the glass substrate in accordance with one or more
embodiments;
[0016] FIG. 3B schematically depicts a cross-section of a process
of etching back the bonding layer to a depth d that extends a
length l into the bonding layer in accordance with one or more
embodiments;
[0017] FIG. 3C schematically depicts a cross-section of a process
of etching back the bonding layer to a depth d that is equal to the
sum of the height h of a distal face of the bonding layer within
the plurality of holes in the glass substrate and length l into the
bonding layer in accordance with one or more embodiments;
[0018] FIG. 4A schematically depicts a cross-section of a metal
filling process in which the electrically conductive material forms
a plurality of vias having a mushroom shape in accordance with one
or more embodiments;
[0019] FIG. 4B schematically depicts a cross-section of a metal
filling process in which the electrically conductive material forms
a plurality of vias having a pillar shape in accordance with one or
more embodiments;
[0020] FIG. 4C schematically depicts a cross-section of a metal
filling process in which the electrically conductive material forms
a plurality of vias having a pillar shape in accordance with one or
more embodiments;
[0021] FIG. 5A schematically depicts a cross-section of a
de-bonding process of the glass substrate having a plurality of
mushroom-shaped vias in accordance with the embodiment shown in
FIG. 4A;
[0022] FIG. 5B schematically depicts a cross-section of a
de-bonding process of the glass substrate having a plurality of
pillar-shaped vias in accordance with the embodiment shown in FIG.
4B; and
[0023] FIG. 5C schematically depicts a cross-section of a
de-bonding process of the glass substrate having a plurality of
pillar-shaped vias in accordance with the embodiment shown in FIG.
4C.
DETAILED DESCRIPTION
[0024] Reference will now be made in detail to various embodiments,
examples of which are illustrated in the accompanying drawings.
Whenever possible, the same reference numerals will be used
throughout the drawings to refer to the same or like parts. One
embodiment of components used in the method of the present
disclosure is shown in FIG. 1, and is designated generally
throughout by the reference numeral 100. The components generally
may include a glass substrate including a plurality of holes bonded
to a glass carrier through a bonding layer. The bonding layer may
be etched through the plurality of holes, filled with an
electrically conductive material, and the glass substrate may be
de-bonded from the glass carrier.
[0025] The methods of the present disclosure enable through-glass
vias to be manufactured in the glass substrate despite challenges
associated with handling of the glass substrate. For example, by
bonding the glass substrate to a glass carrier, challenges
associated with handling a thin glass substrate may be alleviated.
In addition, various embodiments may leverage existing
semiconductor processes and process flow while resulting in more
effective metallization.
[0026] In the embodiment shown in FIG. 1, the glass substrate 102
including a plurality of holes 104 is bonded to a glass carrier 106
through a bonding layer 108. The glass substrate 102 may be used,
for example, as an interposer to provide electrical connections
within a three-dimensional chip. The glass substrate 102 includes a
first face 110 and a second face 112 opposite the first face 110.
Similarly, the glass carrier 106 includes a first face 114 and a
second face 116 opposite the first face 114. The glass carrier 106
may enable manufacturers to reduce a thickness of the glass
substrate 102 without altering their existing manufacturing
processes or facilities. After vias are formed within the glass
substrate 102, the glass substrate 102 is separated from the glass
carrier 106 and the glass carrier 106 may be discarded or reused in
the handling of a subsequent glass substrate. The first face 110 of
the glass substrate 102 is separated from the first face 114 of the
glass carrier 106 by a thickness t of the bonding layer 108.
[0027] The composition and dimensions of the glass substrate 102
are not particularly limited, and are selected based on the desired
end use of the glass substrate 102. The glass substrate 102 may be,
for example, Eagle XG glass, or Code 2318 glass, manufactured by
Corning, Inc. or the like. Additionally, the glass substrate 102
may be in the shape of a wafer having a 4 inch, 6 inch, 8 inch, or
12 inch diameter, for example. Alternatively, the glass substrate
102 may be in the form having any dimensions suitable for its end
use. The thickness of the glass substrate 102 may also vary
depending on its end use. For example, the glass substrate 102 may
have a thickness of from about 30 .mu.m to about 1000 .mu.m, from
about 40 .mu.m to about 500 .mu.m, from about 50 .mu.m to about 200
.mu.m, or about 100 .mu.m. In various embodiments, the glass
substrate 102 has a thickness of less than or equal to about 100
.mu.m. In some embodiments, the glass substrate 102 has a thickness
of less than 100 .mu.m. It should be understood that a glass
substrate of any suitable thickness may be utilized.
[0028] The plurality of holes 104 can be formed in the glass
substrate 102 by any suitable method. For example, in various
embodiments, the plurality of holes 104 is drilled in the glass
substrate 102 using a pulsed laser beam. The laser beam may be any
laser beam having optical properties capable of drilling a
sacrificial cover layer and the glass substrate 102, such as an
ultra-violet (UV) laser beam that is a frequency tripled neodymium
dopes yttrium orthovanadate (Nd:YVO.sub.4) laser, which emits a
wavelength of about 355 nm. The laser beam may be pulsed at a
predetermined location to form each of the plurality of holes 104
in the glass substrate 102. The plurality of holes may also be
mechanically machined in some embodiments.
[0029] As illustrated in FIG. 1, the glass substrate 102 is bonded
to the glass carrier 106. The glass substrate 102 and the glass
carrier 106 may be bonded using a variety of adhesive materials and
may or may not be UV-curable adhesives. The bonding layer may be a
commercially-available adhesive from TOK, BS, 3M, or DuPont,
including but not limited to, 3M UV-Curable Adhesive LC-3200, 3M
UV-Curable Adhesive LC-4200, or 3M UV-Curable Adhesive LC-5200. In
various embodiments, an adhesive is applied to one or both of the
first face 110 of the glass substrate 102 and the first face 114 of
the glass carrier 106. The first face 110 of the glass substrate
102 is brought into contact with the first face 114 of the glass
carrier 106. For example, the adhesive layer can be spin-coated
onto one or both of the first face 110 of the glass substrate and
the first face 114 of the glass carrier 106. Pressure and/or heat
may be applied to the glass substrate 102 and the glass carrier 106
to bond the glass substrate 102 and the glass carrier 106 through
the bonding layer 108.
[0030] In various embodiments, the application of pressure to the
glass substrate 102 and the glass carrier 106 during bonding causes
the bonding layer 108 to extend into at least some of the plurality
of holes 104, forming an adhesive plug 118. As shown in FIG. 1, the
adhesive plug 118 extends into the plurality of holes 104 to a
height h, as measured from the first face 110 of the glass
substrate 102 to a distal face 120 of the adhesive plug 118.
Accordingly, the bonding layer 108 may have a thickness t between
the first face 110 of the glass substrate and the first face 114 of
the glass carrier 106, and a thickness of t plus h inside the
plurality of holes 104, as measured from the distal face 120 of the
adhesive plug 118 to the first face 114 of the glass carrier
106.
[0031] After the glass substrate 102 is bonded to the glass carrier
106, an etch-back process is employed to remove the adhesive plug
118. Removal of the adhesive plug 118 from within the plurality of
holes 104 serves to further shape the plurality of holes 104 by
removing resin and glass fibers so that when the plurality of holes
is filled with electrically conductive material, the electrically
conductive material can smoothly and completely coat the interior
of the holes, thus forming an effective connection between layers
on either side of the glass substrate.
[0032] As shown in FIG. 2, an etchant 200 is introduced through the
plurality of holes 104 at the second face 112 of the glass
substrate 102. The etching process is not particularly limited and
can include wet etching processes or dry etching processes.
[0033] In various embodiments, a wet etch process is employed to
etch back the bonding layer 108. In such embodiments, the etchant
200 may be an etching solvent. The bonding layer 108 can be exposed
to the etching solvent through the plurality of holes 104. The
glass substrate 102 functions as a hard mask for the etching
process. For example, each adhesive plug 118 and portions of the
bonding layer 108 extending from the adhesive plug 118 to the first
face 114 of the glass carrier 106 may be exposed to the etchant
200, while portions of the bonding layer 108 between the first face
110 of the glass substrate 102 and the first face 114 of the glass
carrier 106 where there is no hole may not be exposed to the
etchant 200. Accordingly, the portions of the bonding layer 108
that extend into the plurality of holes 104 (making up the adhesive
plugs 118) and between the adhesive plugs 118 and the first face
114 of the glass carrier 106 may be etched away while the other
portions of the bonding layer 108 remain.
[0034] The etching solvent may include, but is not limited to, at
least one of hydrofluoric acid, ammonium fluoride, nitric acid,
acetic acid, acetone, or combinations thereof. In various
embodiments, the etching solvent can include buffered oxide etch
(i.e., BOE, buffered HF, or BHF) or acetone. Other etching solvents
may be employed, depending on the particular adhesive material in
the bonding layer and the particular glass composition of the glass
substrate 102 and the glass carrier 106. In particular, suitable
etching solvents have high selectivity between the bonding layer
108 and the glass of the glass substrate 102 and the glass carrier
106. The etching solvent may be sprayed on to the glass substrate
102 or the components 100 may be immersed in the etching
solvent.
[0035] In other embodiments, a dry etch process is employed to etch
back the bonding layer 108. In such embodiments, a plasma etcher
may be utilized to etch back the bonding layer 108 using a plasma
generated from an O.sub.2 or Argon-containing gas. Other dry
etching processes may be employed. The dry etch process may be
controlled by time or it can be stopped when the etching reaches
the glass carrier 106.
[0036] Whether the etching is performed using a wet etch process or
a dry etch process, the bonding layer 108 inside the plurality of
holes 104 is etched back through the distal face 120 of the
adhesive plugs 118 such that the adhesive plugs 118 are removed, as
shown in FIG. 2. The duration of the etching process is not limited
and may be determined based on the etch rate and the desired depth
of etch back.
[0037] As shown in FIGS. 3A-3C, in various embodiments, the bonding
layer 108 is etched backed to a depth d through the plurality of
holes 104. As used herein, the depth d represents the depth into
the bonding layer 108 measured from the distal face 120 of the
adhesive plug 118 (e.g., the sum of the depth h plus at least a
portion of the thickness t). For example, when the etch back
process is used to etch back only the adhesive making up the
adhesive plugs 118 and does not etch adhesive material of the
bonding layer 108 past the first face 110 of the glass substrate
102, the depth d is equal to the height h of the adhesive plug 118,
as shown in FIG. 3A. In some embodiments, such as where the bonding
layer 108 does not extend into the plurality of holes 104, the
depth d is less than or equal to the thickness t of the bonding
layer 108, as shown in FIG. 3B. When the etch back process is used
to etch back the adhesive plugs 118 and further etches at least
partially through the thickness t of the bonding layer 108, the
depth d is equal to the sum of the height h plus the portion of the
thickness t, as shown in FIG. 3C. In various embodiments, the
length l represents the length into the bonding layer 108 the
etching extends, as measured from the first face 110 of the glass
substrate 102. For example, in FIG. 3B, the length l is equal to
the depth d, because there was no adhesive plug (e.g., the height h
is equal to zero). In FIG. 3C, the length l is equal to the
difference between the depth d and the height h. Accordingly, the
depth d is equal to the sum of the height h of the adhesive plug,
if any, and the length l.
[0038] Once the etching process is complete, the plurality of holes
104 is filled with an electrically conductive material. The
electrically conductive material may be, by way of example and not
limitation, copper, silver, aluminum, nickel, alloys thereof, and
combinations thereof. In some embodiments, the plurality of holes
104 is filled with a copper-containing material, such as a copper
alloy.
[0039] The filling process may be any suitable metal filling
process, including but not limited to, a wave soldering process,
physically placing a solder paste into the plurality of holes, a
vacuum solder technique, or any other metal filling technique known
or used in the art. In some embodiments, a physical vapor
deposition (PVD, or sputtering) or chemical vapor deposition
process may be used to coat the interior walls of the plurality of
holes 104 with electrically conductive material to form an
electrically conductive layer prior to filling the plurality of
holes 104 with the electrically conductive material. In other
embodiments, deposition of the electrically conductive layer may
include an electroless or electrolytic plating process. In such
embodiments, a seed layer may be formed on the interior walls of
the plurality of holes 104 before the electrically conductive
material is plated. For example, a seed layer may be deposited,
followed by a copper deposition process to form an electrically
conductive layer on the interior walls of the plurality of holes
104. Although some filling processes may include formation of an
electrically conductive layer prior to filling the plurality of
holes 104, formation of the electrically conductive layer may not
be necessary in some embodiments. For example, when vacuum methods
are employed to fill the plurality of holes 104, plating of an
electrically conductive layer may be eliminated.
[0040] FIGS. 4A-4C schematically depict a cross-section of a
process of filling the plurality of holes 104 with an electrically
conductive material. When the plurality of holes 104 are filled
with the electrically conductive material, the electrically
conductive material may completely fill the portion of the bonding
layer 108 that was etched back and the plurality of holes 104. At
least a portion of the electrically conductive material may
protrude from the first face 110 of the glass substrate 102,
extending into the bonding layer 108 to the length l to form a
plurality of vias 400 in the glass substrate 102. As shown in FIG.
4A, in some embodiments, such as when a wet-etch process is used,
the electrically conductive material may fill a mushroom-shaped
void created by the etching process such that the vias 400 include
a portion of the electrically conductive material that protrudes
from the first face 110 of the glass substrate 102.
[0041] In other embodiments, such as the embodiment depicted in
FIGS. 4B and 4C, the etching process may form a one directional
void. For example, when a dry-etch process is employed, the bonding
layer may only be etched in a single direction such that the void
will not expand laterally beyond the first face 110 of the glass
substrate 102. Accordingly, the electrically conductive material
may form a pillar-shaped void, resulting in a pillar-shaped via
400, as shown in FIGS. 4B and 4C. In other words, the via 400 may
have the shape of a cylinder having substantially parallel sides
that extend from the first face 110 of the glass substrate 102 in a
direction that is substantially perpendicular with the first face
110 of the glass substrate 102. In embodiments in which the
dry-etch process utilizes the first face 114 of the glass carrier
106 as a stop layer, the bonding layer 108 is etched to a length l
that is equal to the thickness t of the bonding layer 108 and the
pillar-shaped via 400 may extend from the first face 100 of the
glass substrate 102 the length l, as shown in FIG. 4B. When the
dry-etch process is controlled by time, the bonding layer 108 may
be etched back to a length l into the bonding layer 108, where the
length l is less than the thickness t of the bonding layer 108, and
the pillar-shaped via 400 may extend from the first face 100 of the
glass substrate 102 the length l, as shown in FIG. 4C.
[0042] Once the plurality of holes 104 are filled with the
electrically conductive material 400, the glass substrate 102 may
be de-bonded from the bonding layer 108 and the glass carrier 106,
as shown in FIGS. 5A-5C. De-bonding may be performed using any
suitable process. For example, in embodiments in which the bonding
layer 108 comprises a UV-cured adhesive, a laser may be used to
destroy the bonds between the adhesive and the glass substrate 102.
Other laser and baking methods may be employed to separate the
bonding layer 108 from the glass substrate 102. Alternatively or in
addition, dicing tape may be applied to the glass substrate 102
during the de-bonding process prior to using a laser to de-bond the
glass substrate 102 from the glass carrier 106. In some
embodiments, the glass carrier 106 may first be de-bonded from the
bonding layer 108, and then the bonding layer 108 may be removed
from the glass substrate 102 including the plurality of vias
400.
[0043] In various embodiments, the de-bonding process leaves
substantially no adhesive residue on the glass substrate 102
including the plurality of vias 400. For example, the de-bonding
process may include a step in which de-taping tape (available from
3M) is used to peel the adhesive from the first face 110 of the
glass substrate 102.
[0044] FIG. 5A illustrates the embodiment of FIG. 4A during the
de-bonding process. In particular, the plurality of vias 400
protrude from the first face 110 of the glass substrate 102 when
the glass substrate 102 is de-bonded. In embodiments in which the
bonding layer 108 was etched to the length l, the electrically
conductive material protrudes from the first face 110 of the glass
substrate 102 the length l. Similarly, FIG. 5B and FIG. 5C
illustrate the embodiments of FIG. 4B and FIG. 4C, respectively,
during the de-bonding process. In FIGS. 5B and 5C, the plurality of
vias 400 are pillar shaped, and extend from the first face 100 of
the glass substrate 102. In embodiments in which the bonding layer
108 was etched to the length l into the bonding layer 108, the
pillars extend from the first face 110 of the glass substrate 102
the length l. For example, in FIG. 5B, the length l is equal to the
thickness t of the bonding layer. In FIG. 5C, the length l is less
than the thickness t of the bonding layer.
[0045] It should now be understood that embodiments of the present
disclosure enable through-glass vias to be formed in a thin glass
substrate while leveraging the existing manufacturing processes in
the semiconductor industry. In particular, various embodiments
enable the glass substrate to be removably coupled to a glass
carrier for handling. In various embodiments, the etching back of
the bonding layer further leverages the glass substrate and the
glass carrier to simplify the etching process by reducing or even
eliminating the need for an additional mask and/or stop layer.
[0046] It will be apparent to those skilled in the art that various
modifications and variations can be made to the embodiments
described herein without departing from the spirit and scope of the
claimed subject matter. Thus it is intended that the specification
cover the modifications and variations of the various embodiments
described herein provided such modification and variations come
within the scope of the appended claims and their equivalents.
* * * * *