U.S. patent application number 14/296271 was filed with the patent office on 2017-07-06 for touch panel and fabrication method thereof.
This patent application is currently assigned to TPK Touch Solutions (Xiamen) Inc.. The applicant listed for this patent is TPK Touch Solutions (Xiamen) Inc.. Invention is credited to Yuh-Wen Lee, Fengming Lin, Chuangdai Tang, Xianbin Xu.
Application Number | 20170192543 14/296271 |
Document ID | / |
Family ID | 52007545 |
Filed Date | 2017-07-06 |
United States Patent
Application |
20170192543 |
Kind Code |
A9 |
Lee; Yuh-Wen ; et
al. |
July 6, 2017 |
TOUCH PANEL AND FABRICATION METHOD THEREOF
Abstract
A touch panel and a fabricating method thereof are provided in
the instant disclosure. The touch panel having a non-display area
and a display area includes a shielding layer disposed on a side of
a substrate and defining the non-display area on the substrate; a
sensing electrode layer disposed on the substrate at the same side
as the shielding layer, wherein at least one portion of the sensing
electrode layer is disposed on a surface of the substrate in the
display area; a first protecting layer disposed in the display area
and covering the sensing electrode layer; and a second protecting
layer disposed in the non-display area and covering the shielding
layer. By modifying the structure of the protecting layer, the
height difference between the sensing electrode layer and the
shielding layer may not cause the color difference due to the
non-uniform protecting layer.
Inventors: |
Lee; Yuh-Wen; (Hsinchu,
TW) ; Tang; Chuangdai; (Xiamen, CN) ; Xu;
Xianbin; (Xiamen, CN) ; Lin; Fengming;
(Fuzhou, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TPK Touch Solutions (Xiamen) Inc. |
Xiamen |
|
CN |
|
|
Assignee: |
TPK Touch Solutions (Xiamen)
Inc.
Xiamen
CN
|
Prior
Publication: |
|
Document Identifier |
Publication Date |
|
US 20150355738 A1 |
December 10, 2015 |
|
|
Family ID: |
52007545 |
Appl. No.: |
14/296271 |
Filed: |
June 4, 2014 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G06F 3/04420130101; G06F
2203/04103 20130101; G06F 2203/04107 20130101; G06F 3/0446
20190501; G06F 1/16 20130101; G06F 3/041 20130101; G06F 3/0443
20190501 |
International
Class: |
G06F 3/041 20060101
G06F003/041; G06F 1/16 20060101 G06F001/16 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 4, 2013 |
CN |
201310216959.4 |
Claims
1. A touch panel defining a non-display area and a display area,
the touch panel comprising: a shielding layer disposed on a side of
a substrate, wherein an area of the substrate covered by the
shielding layer defines the non-display area; a sensing electrode
layer disposed on the substrate at the same side as the shielding
layer, wherein at least a portion of the sensing electrode layer
superimposes the display area; a first protecting layer disposed on
the display area and covering the sensing electrode layer; and a
second protecting layer disposed on the non-display area and
covering the shielding layer.
2. The touch panel according to claim 1, wherein the first
protecting layer is a refractive index compensating layer and the
second protecting layer is an attaching layer.
3. The touch panel according to claim 2, wherein the refractive
index compensating layer is made of a material selected from a
group consisting of metal oxide, a non-mental oxide, a
silicon-based material and the combination thereof.
4. The touch panel according to claim 2, wherein the refractive
index compensating layer is composite multilayered.
5. The touch panel according to claim 4, wherein the refractive
index compensating layer is formed by a silicon dioxide (SiO.sub.2)
layer and a niobium pentoxide (Nb.sub.2O.sub.5) layer.
6. The touch panel according to claim 5, wherein the silicon
dioxide layer has a thickness ranging between 30 nm to 50 nm, and
the niobium pentoxide layer has a thickness ranging between 5 nm to
50 nm.
7. The touch panel according to claim 2, wherein the refractive
index of the refractive index compensating layer is larger than or
equal to the refractive index of the sensing electrode layer.
8. The touch panel according to claim 2, wherein the attaching
layer is made of an organic material.
9. The touch panel according to claim 8, wherein the organic
material is selected from the group consisting of the polyimide
material, the ink material, the alcohol material and the
combination thereof.
10. The touch panel according to claim 1, wherein the shielding
layer is made of a polyimide layer or an ink layer.
11. The touch panel according to claim 1, wherein the first
protecting layer further extends to the non-display area and is
formed on the second protecting layer.
12. The touch panel according to claim 1, wherein the sensing
electrode layer further extends to the non-display area, and is
formed on an upper or a lower surface of the shielding layer.
13. The touch panel according to claim 1, further comprising a
signal transmitting layer disposed between the shielding layer and
the second protecting layer, and electrically connected to the
sensing electrode layer.
14. A fabricating method of a touch panel, wherein the touch panel
defines a display area and a non-display area, the method
comprising: forming a shielding layer on a side of a substrate,
wherein an area of the substrate covered by the shielding layer
defines the non-display area; forming a sensing electrode layer at
the same side as the shielding layer on the substrate, wherein at
least a portion of the sensing electrode layer superimposes the
display area; forming a first protecting layer at least on the
display area to cover the sensing electrode layer; and forming a
second protecting layer on non-display area to cover the shielding
layer.
15. The fabricating method of the touch panel according to claim
14, wherein the first protecting layer is a refractive index
compensating layer, and the second protecting layer is an attaching
layer.
16. The fabricating method of the touch panel according to claim
14, wherein the first protecting layer further extends to the
non-display area, and is formed on a surface of the second
protecting layer.
17. The fabricating method of the touch panel according to claim
14, before forming the second protecting layer, further comprising:
forming a signal transmitting layer on a surface of the shielding
layer to electrically connect to the sensing electrode layer.
18. The fabricating method of the touch panel according to claim
14, wherein the sensing electrode layer further extends to the
non-display area, and the sensing electrode layer is formed before
formation of the shielding layer so that the sensing electrode
layer is formed on a lower surface of the shielding layer.
19. The fabricating method of the touch panel according to claim
14, wherein the sensing electrode layer further extends to the
non-display area, and the sensing electrode layer is formed after
formation of the shielding layer so that the sensing electrode
layer is formed on an upper surface of the shielding layer.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention claims the priority of China Patent
Application No. 201310216959.4 filed on Jun. 4, 2013, which is
incorporated by reference in the present application in its
entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to a touch panel technology;
in particular, to a touch panel and a fabrication method
thereof.
DESCRIPTION OF RELATED ART
[0003] As the development of the touch control technology, the
touch panel has been widely used in various consumer electronic
devices, such as smart phone, tablets , digital camera, e-book, MP3
player, and so on, which are portable electronic products. The
touch panel also can be applied to the display screen of the
apparatus for operating and controlling. The touch panel not only
provides convenience of input operation to user, it also has the
advantages in its thinner shape, the lighter weight and the price
competitiveness.
[0004] The touch panel typically includes a substrate, a sensing
electrode layer, a shielding layer and a protective layer. The
protective layer is formed on the both the sensing electrode layer
and the shielding layer to protect the sensing electrode layer from
the physical or chemical damage.
[0005] However, the thickness of the shielding layer is (about ten
to hundred times) thicker than that of the sensing electrode layer.
There is a "step" formed between the shielding layer and the
sensing electrode layer due to the thickness difference
therebetween. While the protective layer is formed on both of the
shielding layer and the sensing electrode layer in the following
process, the step would easily result in the non-uniformity of the
protective layer, and the appearance of the color difference in the
protective layer. The color difference would impact the transparent
property of the touch panel.
BRIEF SUMMARY OF THE INVENTION
[0006] The object of the present invention is related to a touch
panel and fabrication method thereof.
[0007] According to one of the present disclosure, by means of
changing the structure of the protecting layer and adjusting the
processes, the protecting layer having two portions is designed to
deposit on the sensing electrode layer and the shielding layer
respectively. The two portions of the protecting layer are formed
independently, and thus the non-uniform coating for each portion
would not occur despite the existence of thickness difference
between the shielding layer and the sensing electrode layer.
[0008] In order to achieve the aforementioned objects, according to
an embodiment of the present invention, a touch panel is provided.
The touch panel defines a non-display area and a display area
corresponding to the non-display area. The touch panel includes a
shielding layer disposed at a side of a substrate, wherein the
substrate covered by the shielding layer defines the non-display
area; a sensing electrode layer disposed on the substrate at the
same side as the shielding layer, wherein at least a portion of the
sensing electrode layer superimposes the display area; a first
protecting layer disposed in the display area and covering the
sensing electrode layer; and a second protecting layer, disposed in
the non-display area and covering the shielding layer.
[0009] In another embodiment of the instant disclosure, a
fabricating method of the touch panel is provided. The touch panel
defines a display area and a non-display area corresponding to the
display area. The method comprising: forming a shielding layer on a
side of a substrate, wherein an area covered by the shielding layer
defines the non-display area; forming a sensing electrode layer on
the substrate at the same side as the shielding layer, wherein at
least a portion of the sensing electrode layer superimposes the
display area; forming a first protecting layer at least in the
display area to cover the sensing electrode layer; and forming a
second protecting layer in non-display area to cover the shielding
layer.
[0010] As a result, the color difference may be avoided, and the
factors reducing the transparency of the touch panel may be
weakened in the instant disclosure. In addition, the protecting
layer of the instant disclosure has two different portions which
may be made of different materials. In addition to protection, the
first protecting layer covers the sensing electrode layer and has a
refractive index larger than or equal to that of the sensing
electrode, and therefore the difference of the refractive indices
is minimized. In addition to protection, the second protecting
layer, which correspondingly covers the shielding layer and the
signal transmitting layer, also provides a reliable adhesion to the
shielding layer. Taken as a whole, the display quality of the touch
panel can be improved.
[0011] In order to further the understanding regarding the present
invention, the following embodiments are provided along with
illustrations to facilitate the disclosure of the present
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 shows a cross-sectional view of a touch panel
according to a first embodiment of the instant disclosure;
[0013] FIG. 2 shows an enlarged perspective view showing the detail
of the first protecting layer in FIG. 1;
[0014] FIG. 3 shows a cross-sectional view of a touch panel
according to a second embodiment of the instant disclosure;
[0015] FIG. 4 shows a cross-sectional view of a touch panel
according to a third embodiment of the instant disclosure; and
[0016] FIG. 5 is flow chart of the fabrication method for touch
panel according to an embodiment of the instant disclosure.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] The aforementioned illustrations and following detailed
descriptions are exemplary for the purpose of further explaining
the scope of the present invention. Other objectives and advantages
related to the present invention will be illustrated in the
subsequent descriptions and appended drawings.
[0018] The orientations of "upper" and "lower" of the touch panel
in the description of the embodiments are only used to represent
the relative position. In the drawings of the instant disclosure,
the "upper side" of the touch panel means it is the farthest side
from a user, and the "lower side" of the touch panel means it is
the nearest side from the user. Moreover, the touch panel of the
embodiment defines a non-display area and a display area. In
general, the non-display area may be allocated at least one
peripheral side of the display area. All of the embodiments of the
instant disclosure are described in the condition of the
non-display area surrounding the display area.
[0019] Please refer to FIG. 1. FIG. 1 shows a cross-sectional view
of a touch panel according to a first embodiment of the instant
disclosure. The touch panel 100 of the present embodiment includes
a substrate 110, a shielding layer 130, a sensing electrode layer
120, a first protecting layer 151 and a second protecting layer
152. The substrate 110 may be made of the transparent material,
such as glass and the like. The substrate 110 has a lower surface
110a and an upper surface 110b opposite thereto. The lower surface
110a serves as the operating surface for a user. The upper surface
110b is used to form each element of the touch panel 100 thereon,
and the example will be explained in detail in the following
description. Furthermore, in the instant embodiment, the lower
surface 110a of the substrate 110 may be processed by surface
treatments, such as toughening, scratch-resistant process,
anti-glare process, antimicrobial and/or anti-reflective process.
On top of supporting, the surface treatment of the lower surface
110a allows the substrate 110 to be protected.
[0020] The shielding layer 130 is disposed on the peripheral
portion of the upper surface 110b of the substrate 110, and an area
covered by the shielding layer 130 defines the non-display area
100B. In the present embodiment, the shielding layer 130 is an
opaque and insulating layer, such as the black or the other colors
polyimide layer, or ink layer. The shielding layer 130 may be
formed by deposition, lithography and etching processes.
[0021] The sensing electrode layer 120 and the shielding layer 130
are configured on the same side of the substrate 110, i.e. on the
upper side. At least a portion of the sensing electrode layer 120
is configured on the upper surface 110b of the substrate 110 and in
the display area 100B to provide the touch sensitivity for a user.
Specifically, the sensing electrode layer 120 includes a plurality
of first electrodes 121 arranged in rows, a plurality of second
electrodes (not shown in FIG. 1) arranged in columns, and a
plurality of connecting portions 124 connecting a pair of two
immediately adjacent second electrodes (not shown) in the same
column. Every two immediately adjacent first electrodes 121 in the
same row are connected to each other by one of the bridging
portions 123. The sensing electrode layer 120 includes a plurality
of insulating portions 122, each of which is sandwiched between a
pair of the bridging portion 123 and connecting portion 124. The
arrangement of the abovementioned elements (i.e., the first
electrodes 121, the second electrodes, the connecting portions 123,
the bridging portions and the insulating portions 124 of the
sensing electrode layer 120) defines an etching area 120A and a
non-etching area 120B on the sensing electrode layer 120.
[0022] At least a portion of the first protecting layer 151 is
arranged in display area 100B, and covers the sensing electrode
layer 120 at the display area 100B to protect the sensing electrode
layer 120 from the physical or chemical damage. Of course, since
the etching area 120A and non-etching area 120B are defined on the
sensing electrode layer 120, the first protecting layer 151 not
only covers the non-etching area 120B of the sensing electrode
layer 120, but also covers a portion of the substrate 110 appeared
from the etching area 120A. The second protecting layer 152 is
arranged at the non-display area 100B, and superimposes the
shielding layer 130. Since the shielding layer 130 for defining the
non-display area 100B surrounds the display area 100A, in the
instant embodiment, the second protecting layer 152 may have the
frame-like shape.
[0023] As the abovementioned embodiment, by specific designs for
the first protecting layer 151 and the second protecting layer 152,
the protecting layer 150, which is fabricated in the back-end
processes in the whole structure of the touch panel 100, would not
be extremely affected due to the thickness difference between the
shielding layer 130 (with a thickness ranging between 1.5 .mu.m to
20 .mu.m) and the sensing electrode layer 120 (with a thickness
ranging between 250A to 300A). During the fabrication of the
protecting layer 150, the color difference resulting from the
non-uniform coating of the protecting layer 150 may be effectively
avoided, and thus the factors reducing the transparency of the
touch panel 100 may be weakened, and the manufacturing yield of the
touch panel 100 may be increased.
[0024] For the further description, in the present embodiment, the
sequence of the steps, i.e., forming the shielding layer 130 and
then forming the sensing electrode layer 120, is just as an
example. Moreover, the sensing electrode layer 120 may further
extend to top surface of the shielding layer 130, which is arranged
in the non-display area 100B.In one embodiment, as shown in FIG. 1,
the sensing electrode layer 120, which has a portion in the display
area 100A and the other portions in the non-display area 100B, is
fabricated in the same process. In another embodiment, the portion
in the non-display area 100B may be an independent connecting
portion and manufactured by an additional process rather than the
process for manufacturing the other portions in the display area
100A. However, the aforementioned fabrications are not used for
limiting the scope of the instant disclosure.
[0025] The touch panel 100 of the instant embodiment further
includes a signal transmitting layer 160. The signal transmitting
layer 160 is interposed between the shielding layer 130 and the
second protecting layer 152, and electrically connected to the
sensing electrode layer 120 for transmitting the signal between the
sensing electrode layer 120 and an external controller (not shown).
As a result, in the instant embodiment, the second protecting layer
152 in the non-display area 100B may not only cover the shielding
layer 130, but also cover the signal transmitting layer 160 to
protect the signal transmitting layer 160 from the physical or
chemical damage. For example, the signal transmitting layer 160 is
a stack of Mo/Al/Mo layers. The Al layer sandwiched between these
two Mo layers is so chemically reactive that the Al layer is easily
oxidized and forms an insulating aluminum oxide film when the Al
layer is exposed to the air. It is hence the second protecting
layer 152 which may isolate the signal transmitting layer 160 from
the air to prevent the Al layer from the oxidation, and may reduce
the probability of the explosion of the Al layer caused by the
damage of the Mo layer.
[0026] It is worth mentioning that the first protecting layer 151
of the instant embodiment may be a refractive index compensating
layer, and the second protecting layer 152 may be an attaching
layer. As a result, the first protecting layer 151 correspondingly
covering on the sensing electrode layer 120 not only provides the
function of protection, but also compensates and matches the
refractive index of the sensing electrode layer 120 so that the
etching lines formed between the etching area 120A and the
non-etching area 120B on the sensing electrode layer 120 become
visually invisible. The second protecting layer 152 correspondingly
covering the shielding layer 130 and the signal transmitting layer
160 also provides a reliable adhesion to the shielding layer 130 in
addition to providing the function of the protection.
[0027] The refractive index compensating layer, in one embodiment,
may be made of a material selected from a group consisting of the
metal oxide, non-metal oxide, Si-based material and the combination
thereof. The refractive index compensating layer can be designed in
single or multi layers in structure. Given the refractive index of
the refractive index compensating layer of the instant embodiment
is n1, and the refractive index of the sensing electrode layer is
n2. In this case, the refractive index n1 of the refractive index
compensating layer is larger than or equal to the refractive index
n2 of the sensing electrode layer in the instant embodiment.
Therefore, the difference of the refractive indices for visible
light of the etching area 120A and the non-etching area 120B is
minimized. In addition, poor display quality due to different
refractive indices may be avoided, and a better display quality of
the touch panel 100 may be achieved.
[0028] Please refer to FIG. 2. FIG. 2 illustrates an enlarged
perspective view showing the detail of the first protecting layer
in FIG. 1. More specifically, the first protecting layer 151 of the
instant embodiment includes a first refractive index layer 1511 and
a second refractive index layer 1512, which makes the first
protecting layer 151 to be composite multilayered while the first
protecting layer 151 is designed to be the refractive index
compensating layer. The first refractive index layer 1511 covers on
the sensing electrode layer 120, the second refractive index 1512
is disposed on the first refractive index layer 1511. In addition,
with respect to the refractive index n1 of the refractive index
compensating layer, which is composite multilayered, please further
refer to the following description.
[0029] Given the refractive index of the first refractive index
layer 1511 is n3, and the refractive index of the second refractive
index layer 1512 is n4, wherein n3 and n4 meet the following
equations (1)-(3):
n3=sin a/sin b (1)
n4=sin b/sin c (2)
n3*n4=(sin a/sin b)*(sin b/sin c)=sin a/sin c (3)
[0030] Thus, the refractive index n1 of the refractive index
compensating layer, n3 and n4 meet the following equations:
n3=n1*n2.
[0031] By the stacking configuration of the first refractive index
layer 1511 and the second refractive index layer 1512 in the
instant embodiment, the refractive index of the refractive index
compensating layer, which is composite multilayered, is larger than
or equal to that of the sensing electrode layer 120 disposed in the
display area 100B.
[0032] In one embodiment, the refractive index n3 of the first
refractive index layer 1511 is less than the refractive index of
the sensing electrode layer 120, and the refractive index n4 of the
second refractive index layer 1512 is larger than the refractive
index of the sensing electrode layer 120. Specifically, if the
first electrode 121 and the second conductive pattern (not shown)
of the sensing electrode layer 120 are patterned indium tin oxide
(ITO) layers which have the refractive index of 1.86, the first
refractive index layer 1511 would be a layer having smaller
refractive index, for example, silicon dioxide (SiO.sub.2) layer
having a refractive index of 1.46 with a thickness ranging between
30 nm to 50 nm. The second refractive index layer 1512 may be a
layer, the refractive index of which is larger than 1.86, for
example, niobium pentoxide (Nb.sub.2O.sub.5) with a refractive
index of 2.35 and a thickness ranging between 5 nm to 10 nm. In
another embodiment, the first refractive index layer 1511 is
Nb.sub.2O.sub.5 layer, and the second refractive index layer 1512
is SiO.sub.2 layer. In other words, the refractive index
compensating layer being composite multilayered may be, for
example, formed by a SiO.sub.2 layer and a Nb.sub.2O.sub.5 layer
according to the refractive index of the sensing electrode layer
120 in practice.
[0033] The attaching layer, in one embodiment, is an organic
material layer. The properties of the material of the attaching
layer are the same as or similar to that of the shielding layer
130, and the attaching layer thus produces a more reliable adhesion
to the shielding layer 130. The attaching layer composed of the
organic materials undergoes the cross-cut tape test (ASTM
D3359-93), and the adhesion degree of the attaching layer to the
shielding layer 130 is at least 4B. The frequency of stripping is
less than 5%. Accordingly, the signal transmitting layer 160
disposed between the attaching layer and the shielding layer 130
may be completely protected and isolated from the air, and the
probability of the oxidation of the signal transmitting layer 160
is reduced.
[0034] In one embodiment, the organic material may be a polyimide
(PI) material, an ink material, an alcohol material or the
combination thereof. The compositions of the polyimide material
include Silane and Polymethylmethacrylate (PMMA). The compositions
of the ink materials include the pigment, the resin and the
auxiliary agent, wherein the pigment may be titanium dioxide or
toner, and the auxiliary agent may be curing agent or thickening
agent. The alcohol materials may be ethylene glycol, propylene
glycol, ethanol, isopryl alcohol or the combination thereof. The
adhesion of the attaching layer may be optimized by adjusting the
content of each component to provide the better adherence for the
shielding layer 130.
[0035] For the following description, please refer to FIG. 3. FIG.
3 shows a cross-sectional view of a touch panel according to a
second embodiment of the instant disclosure. As shown in FIG. 3,
the structure of the touch panel of the instant embodiment is
substantially similar to the first embodiment as shown in FIG. 1.
The difference is that, in the instant embodiment, the first
protecting layer 151 further extends to the non-display area 100B,
and is formed on the surface of the second protecting layer 152. As
a result, the second protecting layer 152 may be protected from
peeling off. The first protecting layer 151 of the instant
embodiment is completely formed on the surface of the second
protecting layer 152. Of course, according to the demands for the
practical design, the first protecting layer 151 also may be formed
on only one portion of the second protecting layer 152, which is
not intended to limit the scope of the invention.
[0036] Please refer to the FIG. 4. FIG. 4 shows a cross-sectional
view of a touch panel according to a third embodiment of the
instant disclosure. As illustrated in FIG. 4, the structure of the
touch panel of the instant embodiment is substantially similar to
the first embodiment as shown in FIG. 1. In the instant embodiment,
the difference is the stacking sequence of the sensing electrode
layer 120 and the shielding layer 130 of the touch panel 100. In
the instant embodiment, the sequence of the processes is designed
for disposing the sensing electrode layer 120 and then forming the
shielding layer 130. That is to say, the sensing electrode layer
120 in the non-display area 100B is formed on a lower surface of
the shielding layer 130. However, based on the design of the
structure of the instant embodiment, an opening is formed on the
shielding layer 130 to allow electrical communication between the
already formed sensing electrode layer 120 and the signal
transmitting layer 160. Furthermore, the electrical connecting
layer 140 is formed by filling the conductive material into the
opening portion. As a result, the sensing electrode layer 120 is
electrically connected to the signal transmitting layer 160 by the
electrical connecting layer 140 extending through the opening.
[0037] Please refer to the FIG. 5. FIG. 5 is flow chart of the
fabrication method for touch panel according to an embodiment of
the instant disclosure. Firstly, in step S1, a substrate is
provided. In step S2, a shielding layer is formed at a side of the
substrate, and an area of the substrate covered by the shielding
layer 130 defines the non-display area 100B of the touch panel.
[0038] In step S3, a sensing electrode layer is formed on the
substrate at the same side as the shielding layer. In the instant
embodiment, there is at least one portion of the sensing electrode
layer formed on the surface of the substrate and in the display
area of the touch panel, besides, the sensing electrode layer
further extends to the non-display area and is arranged on the
upper surface of the shielding layer in the non-display area formed
in step S2.
[0039] Of course, in another embodiment, the order of the above
step S2 and the above step S3 can also be exchanged. That is to
say, the sensing electrode is formed, and the shielding layer is
subsequently formed. It is thus the sensing electrode layer
extending to the non-display area is arranged on the lower surface
of the shielding layer.
[0040] In step S4, a signal transmitting layer is formed on the
shielding layer to electrically connect to the sensing electrode
layer.
[0041] In step S5, a first protecting layer is at least formed in
the display area to cover the sensing electrode layer.
[0042] In step S6, a second protecting layer is formed to cover the
shielding layer and the signal transmitting layer in the
non-display area. The touch panel of the instant embodiment could
be fabricated by performing the aforementioned steps.
[0043] In another embodiment, the order of the abovementioned step
S5 and step S6 can also be exchanged. That is to say, the second
protecting layer can be formed, and thereafter the first protecting
layer is formed. As a result, the first protecting layer can be
designed to be not merely formed in the display area, but extend to
the surface of the second protecting layer in the non-display area
so as to prevent the second protecting layer from peeling off.
[0044] At last, additional explanations may be provided. In each of
the abovementioned embodiments, the insulating portion can be made
by coating, lithography and etching processes, which are performed
in sequence. Besides, the insulating portion is made of for example
epoxy layer, polyimide layer or methyl methacrylate layer and so
on. Additionally, the first electrode, the second electrode or the
signal transmitting layer also may be manufactured by the
deposition, the lithography, the etching processes and so on.
[0045] The aforementioned deposition process for example physical
vapor deposition (PVD) or chemical vapor deposition (CVD). The
physical vapor deposition (PVD) is such as evaporation or
sputtering deposition, and the chemical vapor deposition is such as
low pressure chemical vapor deposition (LPCVD), metal-organic
chemical vapor deposition (MOCVD), plasma-enhanced chemical vapor
deposition (PECVD) or photo chemical vapor deposition (PHOTO CVD).
The aforementioned etching process may be chemical etching or laser
etching process.
[0046] Furthermore, the first electrode and the second electrode of
the aforementioned embodiments may be made of the transparent
conductive material. The transparent conductive material such as
indium tin oxide (ITO), indium zinc oxide (IZO), cadmium tin oxide
(CTO), aluminum zinc oxide (AZO), indium tin zinc oxide (ITZO),
zinc oxide, cadmium oxide, hafnium oxide (HfO), indium gallium zinc
oxide (InGaZnO), indium gallium zinc magnesium oxide (InGaZnMgO),
indium gallium magnesium oxide (InGaMgO) or indium gallium aluminum
oxide (InGaAlO) and the like. Besides, the signal transmitting
layer 160 may be made of Au, Ag, Cu, Ni, Al, Cr or the combination
thereof, for example, the structure of the signal transmitting
layer 160 is a Mo/Al/Mo stack, wherein the Al layer is sandwiched
between the two Mo layers.
[0047] In summary, the color difference may be avoided, and the
factors reducing the transparency of the touch panel may be
weakened. In addition, the protecting layer has two different
portions which may be made of different materials. In addition to
protection, the first protecting layer covers the sensing electrode
layer and has a refractive index larger than or equal to that of
the sensing electrode, and therefore the difference of the
refractive indices is minimized. In addition to protection, the
second protecting layer, which correspondingly covers the shielding
layer, provides a reliable adhesion to the shielding layer. Taken
as a whole, the display quality of the touch panel can be
improved.
[0048] The descriptions illustrated supra set forth simplify the
preferred embodiments of the present invention; however, the
characteristics of the present invention are by no means restricted
thereto. All changes, alterations, or modifications conveniently
considered by those skilled in the art are deemed to be encompassed
within the scope of the present invention delineated by the
following claims.
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