CN113934320B

CN113934320B - Touch display device

Info

Publication number: CN113934320B
Application number: CN202111098171.9A
Authority: CN
Inventors: 廖启昇; 简伯儒; 张宗隆
Original assignee: AU Optronics Corp
Current assignee: AU Optronics Corp
Priority date: 2020-11-06
Filing date: 2021-09-18
Publication date: 2023-12-08
Anticipated expiration: 2041-09-18
Also published as: CN113934320A

Abstract

The invention discloses a touch display device which is provided with a display area and a peripheral area and comprises a substrate, a signal wire, a connecting pad and a protective layer. The signal line is located on the substrate and extends from the display area to the peripheral area. The pad is located in the peripheral region and electrically connected with the signal line. The protection layer is positioned on the signal wire and the connecting pad, is provided with a through hole overlapping the connecting pad and comprises a flat part and an annular hole part, wherein the flat part surrounds the annular hole part and has a first height, the annular hole part forms the side wall of the through hole and has a second height, and the first height is larger than the second height.

Description

Touch display device

Technical Field

The present invention relates to a touch display device, and more particularly, to a touch display device with improved scratch resistance.

Background

According to the relative positions of the touch electrodes and the display panel, the touch display device is generally divided into an out-cell, an on-cell and an in-cell, wherein the out-cell touch display device has the advantages of being lighter and thinner than the out-cell touch display device and having lower technical difficulty than the in-cell touch display device, and is widely applied to various electronic products.

In the external embedded touch display device, the touch related elements are disposed on the back surface of the color filter substrate, so that a single-board double-sided manufacturing process is required in the manufacturing process, so that the touch related elements and the color filter elements are respectively formed on two opposite surfaces of the substrate, and then, film flip chip packaging (COF) is performed through, for example, an external lead bonding (Outer Lead Bonding) technology. However, when the substrate is turned over and transferred to perform the color filter device manufacturing process after the touch related devices are formed, the touch related devices often generate scratches due to contact with a transfer mechanism (e.g., a transfer roller) during the transfer process.

Disclosure of Invention

The invention provides a touch display device with improved scratch resistance.

An embodiment of the invention provides a touch display device having a display area and a peripheral area, and comprising: a substrate; the signal line is positioned on the substrate and extends from the display area to the peripheral area; the connecting pad is positioned in the peripheral area and is electrically connected with the signal wire; and a protective layer located on the signal line and the pad, having a through hole overlapping the pad, and including a flat portion and an annular hole portion, wherein the flat portion surrounds the annular hole portion and has a first height, the annular hole portion forms a sidewall of the through hole and has a second height, and the first height is greater than the second height.

In an embodiment of the invention, a difference between the second height and the height of the bonding pad is less than or equal to 0.8 μm.

In an embodiment of the invention, the pad includes a single-layer or multi-layer structure.

In an embodiment of the invention, the pad includes a first conductive layer and a second conductive layer, the second conductive layer completely covers the first conductive layer, and a sidewall of the through hole completely covers a periphery of the second conductive layer.

In an embodiment of the invention, the signal line includes a first signal line and a second signal line, and the first conductive layer and the first signal line belong to the same film layer, and the second conductive layer and the second signal line belong to the same film layer.

In an embodiment of the invention, the touch display device further includes a transfer wire, wherein the transfer wire is electrically connected to the second signal line and the first conductive layer, and the transfer wire and the first signal line belong to the same film layer.

In an embodiment of the invention, the second signal line is electrically connected to the transfer wire through the through hole.

In an embodiment of the invention, the protection layer is formed by a phase transfer photomask, a half tone photomask or a gray tone photomask manufacturing process.

In an embodiment of the invention, the signal line is separated from the pad.

In an embodiment of the invention, the signal line bridges the pad through a transparent conductive line.

In an embodiment of the invention, the protective layer includes an organic material.

In an embodiment of the invention, the signal line includes an end wide portion overlapping the transparent conductive line, and a line width of the end wide portion is smaller than a line width of the transparent conductive line.

In an embodiment of the invention, a difference between the line width of the transparent conductive line and the line width of the end wide portion is greater than or equal to 6 μm.

In an embodiment of the invention, a line width of the end wide portion is greater than a line width of the signal line in the display area.

In an embodiment of the invention, the touch display device further includes a polarizer, a transparent conductive line covering the signal line and a portion of the transparent conductive line, and a distance between the end wide portion and an edge of the polarizer is greater than or equal to 500 μm.

In order to make the above features and advantages of the present invention more comprehensible, embodiments accompanied with figures are described in detail below.

Drawings

Fig. 1A is a schematic top view of a touch display device 10 according to an embodiment of the invention;

FIG. 1B is a schematic cross-sectional view taken along section line A-A' of FIG. 1A;

FIG. 1C is a schematic cross-sectional view taken along section line B-B' of FIG. 1A;

fig. 2A is a schematic top view of a touch display device 20 according to an embodiment of the invention;

FIG. 2B is a schematic cross-sectional view taken along section line C-C' of FIG. 2A;

FIG. 2C is a schematic cross-sectional view taken along section line D-D' of FIG. 2A;

FIG. 2D is a schematic cross-sectional view taken along section line E-E' of FIG. 2A;

fig. 3 is a flowchart of a method for manufacturing the touch display device 20 shown in fig. 2A;

fig. 4A is a schematic top view of a touch display device 30 according to an embodiment of the invention;

FIG. 4B is a schematic cross-sectional view taken along section line F-F' of FIG. 4A;

FIG. 4C is a schematic cross-sectional view taken along section line G-G' of FIG. 4A;

FIG. 4D is a schematic cross-sectional view taken along section line H-H' of FIG. 4A;

fig. 4E is an enlarged schematic view of an area I of the touch display device 30 of fig. 4A;

fig. 5 is a flowchart of a method for manufacturing the touch display device 30 of fig. 4A.

Symbol description

10. 20, 30: touch display device

110: substrate board

120. 320: signal line

121. 321: first signal line

122. 322: second signal line

122T: transfer wire

130. 230, 330: connecting pad

131. 231, 331: a first conductive layer

132. 232, 332: second conductive layer

140. 340: protective layer

141. 341: flat part

142. 342: annular hole part

233: third conductive layer

351. 352: transparent conducting wire

360: polarizer sheet

AA: display area

A-A ', B-B', C-C ', D-D', E-E ', F-F', G-G ', H-H': section line AD: conductive adhesive

BA: peripheral region

COF: flip-chip film

D1: depth of

E1: end wide portion

E2: end wide portion

H1: first height of

H2: second height

And H3: height of (1)

I: region(s)

I1: insulating layer

I2: organic insulating layer

And I3: organic protective layer

LD: pin

O1: an opening

Rx: touch sensing electrode

S11, S12, S13, S14, S15: step (a)

S21, S22, S23, S24, S25: step (a)

TH: through hole

Tx: touch control driving electrode

V1: through hole

X0, X1, X2: line width

Y: distance of

Detailed Description

Fig. 1A is a schematic top view of a touch display device 10 according to an embodiment of the invention. FIG. 1B is a schematic cross-sectional view taken along section line A-A' of FIG. 1A. FIG. 1C is a schematic cross-sectional view taken along section line B-B' of FIG. 1A. In order to simplify the drawing, the pin LD and the conductive adhesive AD in fig. 1B are omitted in fig. 1A.

Referring to fig. 1A to 1C, the touch display device 10 has a display area AA and a peripheral area BA, and includes a substrate 110, a signal line 120, a pad 130 and a passivation layer 140. The signal line 120 is disposed on the substrate 110 and extends from the display area AA to the peripheral area BA. The pad 130 is located in the peripheral area BA and is electrically connected to the signal line 120. The passivation layer 140 is disposed on the signal line 120 and the pad 130, has a through hole TH overlapping the pad 130, and includes a flat portion 141 and an annular hole portion 142, wherein the flat portion 141 surrounds the annular hole portion 142 and has a first height H1, the annular hole portion 142 forms a sidewall of the through hole TH and has a second height H2, and the first height H1 is greater than the second height H2.

As described above, in the touch display device 10 according to an embodiment of the invention, the depth of the through hole TH is controlled by the annular hole 142 with a smaller height in the protection layer 140, which is helpful for the bonding of the pad 130. Meanwhile, the flat portion 141 with a larger height in the protection layer 140 covers the signal line 120 and surrounds the annular hole 142, so that the signal line 120 and the pad 130 are prevented from being scratched during the manufacturing process, and the touch display device 10 has improved scratch resistance.

Hereinafter, embodiments of the elements and the film layers of the touch display device 10 will be described with reference to the drawings, but the invention is not limited thereto.

Referring to fig. 1A to 1C, the substrate 110 of the touch display device 10 may be a transparent substrate, and the material of the substrate includes a quartz substrate, a glass substrate, a polymer substrate, etc., but the invention is not limited thereto. The substrate 110 may be provided thereon with various film layers for forming, for example, touch electrodes, signal lines, pads, color filter elements, black matrices, switching elements, and the like. In some embodiments, the touch display device 10 may include another substrate (e.g. a pixel array substrate) and a display medium disposed between the other substrate and the substrate 110, but fig. 1A to 1C omit the other substrate and the display medium for clarity of the drawings.

The signal line 120 of the touch display device 10 is a conductive line for transmitting signals, and the signal line 120 may include a first signal line 121 and a second signal line 122, where the first signal line 121 and the second signal line 122 may be used for transmitting signals with different properties. For example, in the present embodiment, the touch display device 10 may include a plurality of touch driving electrodes Tx and a plurality of touch sensing electrodes Rx alternately disposed in the display area AA, and the first signal lines 121 may be connected to the touch driving electrodes Tx and the second signal lines 122 may be connected to the touch sensing electrodes Rx. When an object (e.g., a stylus pen) touches the touch display device 10, the capacitance between the touch driving electrode Tx and the touch sensing electrode Rx is changed, and at this time, the touch driving electrode Tx and the touch sensing electrode Rx can respectively guide out the signals of the sensed capacitance changes to the peripheral area BA through the first signal line 121 and the second signal line 122.

In some embodiments, the touch display device 10 further includes a Chip On Film (COF). A plurality of leads LD are provided on the flip film COF, one end of the leads LD is electrically connected to, for example, a chip on the flip film COF, and the other end of the leads LD may be bonded to the bonding pads 130 located in the peripheral area BA by a conductive paste AD or other conductive material. Therefore, the first signal line 121 and the second signal line 122 can transmit the capacitance change signal to the chip on the flip film COF through the pad 130 to calculate the coordinates of the contact point.

In other embodiments, the touch display device 10 may include a plurality of switching elements located in the display area AA. The switching element is, for example, a thin film transistor composed of a gate electrode, a semiconductor channel, a source electrode, and a drain electrode, and the first signal line 121 may be connected to the gate electrode of the switching element as a scan line, while the second signal line 122 may be connected to the source electrode of the switching element as a data line. Similarly, when the touch display device 10 performs a display operation, the chip on the flip film COF may turn on or off the switching element by transmitting signals through the pad 130 and the first signal line 121, and when the switching element is turned on, the signals transmitted to the source of the switching element through the pad 130 and the second signal line 122 may be transmitted to the drain of the switching element.

The contact pad 130 of the touch display device 10 may have a single-layer or multi-layer structure. Referring to fig. 1C, in the present embodiment, the pad 130 has a dual-layer structure and includes a first conductive layer 131 and a second conductive layer 132, wherein the second conductive layer 132 covers the first conductive layer 131, but the invention is not limited thereto. For example, the first conductive layer 131 may be the same film as the first signal line 121 or the second signal line 122, and may include the same material as the first signal line 121 or the second signal line 122, such as a metal with good conductivity, e.g. aluminum, molybdenum, titanium, etc.

In the present embodiment, the first signal line 121 and the second signal line 122 respectively extend from the display area AA to the peripheral area BA, and the first signal line 121 and the second signal line 122 are respectively electrically connected to the pad 130. In some embodiments, the first signal line 121 and the second signal line 122 may be electrically connected to the first conductive layer 131 of the pad 130, respectively. In some embodiments, the first conductive layer 131 and the first signal line 121 may belong to the same layer, and the first signal line 121 is physically connected to the first conductive layer 131 of the pad 130, and the second signal line 122 is electrically connected to the pad 130 through other conductive structures or conductive elements. In some embodiments, the first conductive layer 131 and the second signal line 122 may belong to the same layer, and the second signal line 122 is physically connected to the first conductive layer 131 of the pad 130, and the first signal line 121 is electrically connected to the pad 130 through other conductive structures or conductive elements. In some embodiments, the first conductive layer 131 may be a part of the first signal line 121 or the second signal line 122, for example, the first signal line 121 and the second signal line 122 may be used as the first conductive layer 131 at the end of the peripheral area BA.

In some embodiments, the material of the second conductive layer 132 may be a metal oxide to protect the first conductive layer 131 from being eroded by the etchant during the subsequent etching process. For example, the material of the second conductive layer 132 may be indium tin oxide, indium zinc oxide, indium gallium zinc oxide or other transparent conductive materials, but the invention is not limited thereto.

The flat portion 141 of the passivation layer 140 may be located in the display area AA and the peripheral area BA. In the display area AA, the flat portion 141 may cover the signal line 120, the touch driving electrode Tx, the touch sensing electrode Rx, and the like, while in the peripheral area BA, the flat portion 141 may surround the annular ring portion 142. The flat portion 141 has a sufficient thickness and hardness to protect the above-mentioned components located in the display area AA and the bonding pad 130 located in the peripheral area BA from being scratched or damaged during the manufacturing process. For example, when the touch display device 10 is conveyed by a conveying Roller (Roller), the protection layer 140 may contact the Roller, and the flat portion 141 may support the Roller such that the Roller cannot touch the annular hole 142, and thus the Roller cannot touch the contact pad 130 naturally, so as to protect the contact pad 130 from being scratched by the Roller.

The through holes TH of the protection layer 140 expose the pads 130 so that the pads 130 can be bonded with other devices. However, the depth D1 of the through holes TH may not be excessively large so that the conductive particles in the conductive paste AD can electrically connect the pads 130 with the leads LD. Accordingly, the annular hole portion 142 having a low height is utilized as a sidewall of the through hole TH, that is, the through hole TH is formed in the annular hole portion 142. In some embodiments, the depth D1 of the through hole TH is substantially equal to the difference between the second height H2 of the annular hole 142 and the height H3 of the pad 130, and the depth D1 is preferably less than or equal to 0.8 μm, for example, the depth D1 may be 0.8 μm, 0.6 μm or 0.4 μm, but the invention is not limited thereto.

On the other hand, the annular ring portion 142 may cover the periphery of the pad 130 to protect the periphery of the pad 130 from the manufacturing process or the testing environment. For example, in the present embodiment, the second conductive layer 132 completely covers the first conductive layer 131, and the annular ring portion 142 completely covers the periphery of the second conductive layer 132. In some embodiments, the annular ring portion 142 may also completely overlap the periphery of the first conductive layer 131 and the periphery of the second conductive layer 132.

In some embodiments, the protective layer 140 may include an organic insulating layer suitable for ultra-high opening technology (Ultra High Aperture, UHA). For example, the material of the protection layer 140 may include a transparent insulating material, such as an organic material, an acrylic (acrylic) material, a siloxane (siloxane) material, a polyimide (polyimide) material, an epoxy (epoxy) material, etc., but the invention is not limited thereto. The flat portion 141, the annular hole portion 142 and the through hole TH of the protection layer 140 may be formed by performing an exposure and development process and a subsequent curing process through a phase shift mask (phase shift mask), a half tone mask (half tone mask) or a gray tone mask (gray tone mask). That is, after one exposure process, the insulating material can be formed into different exposure levels of the highly exposed portion, the semi-exposed portion and the unexposed portion, and after the development process, the insulating material can be patterned into the protective layer 140 having the flat portions 141, the annular hole portions 142 and the through holes TH with different heights. After development, a curing process may be performed to densify the structure of the protective layer 140 and to be cured.

Hereinafter, other embodiments of the present invention will be described with reference to fig. 2A to 2D; and, the element numerals and the related contents of the embodiment of fig. 1A to 1C are used, wherein the same or similar numerals are used to designate the same or similar elements, and the description of the same technical contents is omitted. Regarding the description of the omitted parts, reference may be made to the embodiments of fig. 1A to 1C, and the description will not be repeated.

Fig. 2A is a schematic top view of a touch display device 20 according to an embodiment of the invention. Fig. 2B is a schematic cross-sectional view taken along section line C-C' of fig. 2A. FIG. 2C is a schematic cross-sectional view taken along section line D-D' of FIG. 2A. FIG. 2D is a schematic cross-sectional view taken along section line E-E' of FIG. 2A.

The touch display device 20 shown in fig. 2A to 2D is different from the touch display device 10 shown in fig. 1A to 1C in that: the passivation layer 140 and the signal line 120 further include an insulating layer I1 therebetween, and the pad 230 includes a first conductive layer 231, an insulating layer I1, a second conductive layer 232, and a third conductive layer 233.

Referring to fig. 2A to 2D, in the present embodiment, the protection layer 140 has a through hole TH overlapping the pad 230, and includes a flat portion 141 and an annular hole portion 142. The protection layer 140 is disposed on the insulation layer I1, and the insulation layer I1 is disposed between the first conductive layer 231 and the second conductive layer 232. The insulating layer I1 has an opening O1, and the second conductive layer 232 can be connected to the first conductive layer 231 through the opening O1. The insulating layer I1 may be formed by a high temperature fabrication process, for example, the insulating layer I1 may be formed by a Chemical Vapor Deposition (CVD) fabrication process at 200 ℃ or higher. The material of the insulating layer I1 may include a transparent insulating material, such as silicon oxide, silicon nitride, silicon oxynitride, and the like. Therefore, the structure of the touch display device 20 is similar to that of the touch device manufacturing process performed before the color filter substrate and the pixel array substrate.

In the embodiment, the first conductive layer 231 and the first signal line 121 may belong to the same layer, and the second conductive layer 232 and the second signal line 122 may belong to the same layer, but the invention is not limited thereto. In some embodiments, the second signal line 122 may be connected to the transfer wire 122T through the through hole V1 in the insulating layer I1, the transfer wire 122T is electrically connected to the first conductive layer 231 of the pad 230, and the transfer wire 122T and the first conductive layer 231 are both in the same layer as the first signal line 121, and the second signal line 122 and the first signal line 121 are in different layers. In this way, the transfer wire 122T can electrically connect the second signal wire 122 and the first conductive layer 231 of the pad 230. In some embodiments, the first conductive layer 231 and the second conductive layer 232 may include a metal with good conductivity, such as aluminum, molybdenum, titanium, and the like.

The third conductive layer 233 may be made of metal oxide to protect the second conductive layer 232 and the first conductive layer 231 from being corroded by the etchant during the subsequent etching process. For example, the material of the third conductive layer 233 may be indium tin oxide, indium zinc oxide, indium gallium zinc oxide or other transparent conductive materials, but the invention is not limited thereto.

Fig. 3 is a flowchart of a method for manufacturing the touch display device 20 shown in fig. 2A. Referring to fig. 2A to fig. 2D and fig. 3, in step S11, a first signal line 121, a first conductive layer 231 and a transfer conductive line 122T are formed on the substrate 110, wherein the first signal line 121 is electrically connected to the first conductive layer 231, and the transfer conductive line 122T is electrically connected to the first conductive layer 231. In this step, a plurality of touch driving electrodes Tx may be formed at the same time. Next, in step S12, an insulating layer I1 having an opening O1 and a via V1 is formed on the substrate 110, and the opening O1 overlaps the first conductive layer 231, and the via V1 overlaps the transfer wire 122T. Next, in step S13, a second signal line 122 and a second conductive layer 232 are formed on the substrate 110, wherein the second signal line 122 overlaps the through hole V1, and the second signal line 122 is electrically connected to the transfer wire 122T through the through hole V1; the second conductive layer 232 overlaps the opening O1, and the second conductive layer 232 may be electrically connected to the first conductive layer 231 through the opening O1. In this step, a plurality of touch sensing electrodes Rx may be formed at the same time, and the signal line 120 includes a first signal line 121 and a second signal line 122. Next, in step S14, a third conductive layer 233 is formed on the second conductive layer 232, and the pad 230 includes the first conductive layer 231, the insulating layer I1, the second conductive layer 232, and the third conductive layer 233. Next, in step S15, a protection layer 140 is formed on the signal line 120 and the pad 230 using, for example, a half tone mask (half tone mask), and the protection layer 140 may include a flat portion 141 and an annular hole portion 142, wherein the first height H1 of the flat portion 141 is greater than the second height H2 of the annular hole portion 142, and the annular hole portion 142 has a through hole TH overlapping the pad 230. In this way, by the structural design of the flat portion 141, the annular hole portion 142 and the through hole TH with different heights, the signal line 120, the pad 230 and other components can be prevented from being scratched in the manufacturing process under the condition that the pad 230 has a structure suitable for being connected, so that the touch display device 20 has improved scratch resistance.

Fig. 4A is a schematic top view of a touch display device 30 according to an embodiment of the invention. FIG. 4B is a schematic cross-sectional view taken along section line F-F' of FIG. 4A. Fig. 4C is a schematic cross-sectional view taken along section line G-G' of fig. 4A. Fig. 4D is a schematic cross-sectional view taken along section line H-H' of fig. 4A. Fig. 4E is an enlarged schematic view of the area I of the touch display device 30 of fig. 4A.

The touch display device 30 shown in fig. 4A to 4E is different from the touch display device 10 shown in fig. 1A to 1C in that: the first signal line 321 and the second signal line 322 of the signal line 320 are bridged to the connecting pad 330 through the transparent wires 351 and 352 respectively; the flat portion 341 of the protection layer 340 includes an organic insulation layer I2 and an organic protection layer I3, and the annular hole portion 342 of the protection layer 340 includes the organic protection layer I3; and the organic insulating layer I2 is sandwiched between a film layer forming the first signal line 321 and a film layer forming the second signal line 322.

Referring to fig. 4A to fig. 4E, in the present embodiment, the pad 330 may include a dual-layer structure formed by stacking the first conductive layer 331 and the second conductive layer 332, and the first conductive layer 331 and the first signal line 321 may belong to the same layer, and the second conductive layer 332 and the second signal line 322 may belong to the same layer. In some embodiments, the pad 330 may also have a single-layer structure similar to the first conductive layer 131 described above. In other embodiments, the pad 330 may have a structure in which three or more conductive layers are stacked.

In the present embodiment, the first signal line 321 is structurally separated from the pad 330, and the second signal line 322 is structurally separated from the pad 330. In addition, the transparent conductive line 351 covers the end wide portion E1 of the first signal line 321 and the pad 330, and the transparent conductive line 351 bridges the end wide portion E1 and the pad 330, that is, the first signal line 321 bridges the pad 330 through the transparent conductive line 351. Meanwhile, the transparent conductive line 352 covers the end wide portion E2 of the second signal line 322 and the pad 330, and the transparent conductive line 352 bridges the end wide portion E2 and the pad 330, that is, the second signal line 322 bridges the pad 330 through the transparent conductive line 352. In some embodiments, the end wide portions E1, E2 may each comprise a single-layer or multi-layer structure, such as a structure in which a plurality of conductive layers are stacked. Furthermore, the through holes TH overlap only the central portion of the bonding pad 330, and the annular hole portion 342 of the protection layer 340 overlaps the peripheral edge of the bonding pad 330. The pad 330 and the transparent conductive lines 351 and 352 are covered by the annular ring portion 342 of the protection layer 340, so that the pad 330 is protected from the manufacturing process or the testing environment.

Referring to fig. 4E, in some embodiments, the line width X1 of the end wide portion E2 of the second signal line 322 is greater than the line width X0 of the second signal line 322 in the display area AA, so that the contact area between the second signal line 322 and the transparent conductive line 352 can be increased, so as to reduce the contact impedance between the second signal line 322 and the transparent conductive line 352, thereby improving the current stress resistance (current stress) performance of the second signal line 322. Similarly, the line width of the end wide portion E1 of the first signal line 321 is also greater than the line width of the first signal line 321 in the display area AA.

In some embodiments, the line width X1 of the end wide portion E2 of the second signal line 322 may be smaller than the line width X2 of the transparent conductive line 352, such that the transparent conductive line 352 may completely cover the end wide portion E2 of the second signal line 322. In some embodiments, the difference between the line width X2 of the transparent conductive line 352 and the line width X1 of the end wide portion E2 may be greater than or equal to 6 μm, that is, X2-x1+.6μm, for example, x2-x1=6μm, x2-x1=8μm, or x2-x1=10μm, to ensure that the transparent conductive line 352 may completely cover the end wide portion E2 of the second signal line 322. Similarly, the line width of the end wide portion E1 of the first signal line 321 may be smaller than that of the transparent conductive line 351, and the difference between the line width of the transparent conductive line 351 and the line width of the end wide portion E1 may be greater than or equal to 6 μm.

Referring to fig. 4A and fig. 4E, in some embodiments, the touch display device 30 further includes a polarizer 360, and the polarizer 360 covers, for example, the touch driving electrode Tx, the touch sensing electrode Rx, the first signal line 321, the second signal line 322, and a portion of the transparent conductive lines 351 and 352. Based on the film shrinkage consideration after the attachment accuracy and reliability test of the polarizer 360, the distance Y between the end wide portion E2 of the second signal line 322 and the edge of the polarizer 360 may be greater than or equal to 500 μm, for example, the distance Y may be 500 μm, 800 μm or 1,200 μm, so as to ensure that the polarizer 360 may completely cover the end wide portion E2, and to prevent the second signal line 322, especially the end wide portion E2, from causing visual interference due to light reflection. Likewise, the distance between the end wide portion E1 of the first signal line 321 and the edge of the polarizer 360 may be greater than or equal to 500 μm.

The protection layer 340 includes an organic material, for example, in the present embodiment, the flat portion 341 of the protection layer 340 includes an organic insulation layer I2 and an organic protection layer I3, and the annular hole portion 342 of the protection layer 340 includes the organic protection layer I3. The organic insulating layer I2 and the organic protective layer I3 may be formed by a low temperature fabrication process, for example, the organic insulating layer I2 and the organic protective layer I3 may be formed by a spin coating (spin coating) fabrication process at 200 ℃ or less. Therefore, the structure of the touch display device 30 is similar to that of the touch device fabricated by the fabrication process after the color filter substrate and the pixel array substrate are combined.

The material of the organic insulating layer I2 may include various dielectric polymers, such as vinyl polymers obtained by polymerizing one or more acyclic vinyl monomers, polymers derived from one or more vinyl phenol monomers (e.g., poly-4-vinyl phenol (PVP)), or copolymers of vinyl phenol or vinyl phenol derivatives with at least one other vinyl monomer. Examples of the above acyclic vinyl monomer include ethylene, propylene, butadiene, styrene, vinyl phenol, vinyl chloride, vinyl acetate, acrylic esters (e.g., methacrylic esters, methyl methacrylate, acrylic acid, methacrylic acid, acrylamide), acrylonitrile, and derivatives thereof. The vinyl monomer may be an acrylic monomer such as methyl methacrylate, acrylic acid, methacrylic acid, acrylamide or derivatives thereof.

The material of the organic protective layer I3 may include a polymer having hydroxyl side chains to react with carboxylic acid containing (vinylidene or) diene or its derivatives. For example, the organic protective layer I3 may include poly (2-hydroxyethyl methacrylate), poly (vinyl alcohol), and copolymers thereof, such as poly (vinyl alcohol-co-ethylene) or poly (vinyl phenol/methyl methacrylate), and the like.

Fig. 5 is a flowchart of a method for manufacturing the touch display device 30 of fig. 4A. In step S21, a first signal line 321 and a first conductive layer 331 are formed on the substrate 110. In this step, a plurality of touch driving electrodes Tx may be formed at the same time. Next, in step S22, an organic insulating layer I2 is formed on the substrate 110. Next, in step S23, a second signal line 322 and a second conductive layer 332 are formed on the substrate 110. In this step, a plurality of touch sensing electrodes Rx may also be formed simultaneously. Next, in step S24, transparent conductive lines 351 and 352 are formed, wherein the transparent conductive line 351 covers the end wide portion E1 of the first signal line 321 and the second conductive layer 332, and the transparent conductive line 352 covers the end wide portion E2 of the second signal line 322 and the second conductive layer 332. Next, in step S25, an organic protective layer I3 is formed on the substrate 110, and the organic protective layer I3 has a through hole TH overlapping the second conductive layer 332. In this way, by the structural design of the flat portion 341, the annular hole portion 342 and the through hole TH with different heights, the signal line 320 and the pad 330 can be prevented from being scratched in the manufacturing process under the condition that the pad 330 has a structure suitable for being connected, so that the touch display device 30 has improved scratch resistance.

In summary, in the touch display device according to the embodiment of the invention, the depth of the through hole is controlled by the annular hole portion with a smaller height in the protection layer, which is beneficial to the bonding of the bonding pad. Meanwhile, the flat part with larger height in the protective layer covers the signal wire and surrounds the annular hole part, so that the signal wire and the connecting pad can be prevented from being scratched in the manufacturing process, and the touch display device has improved scratch resistance. In addition, the annular hole part is used to cover the periphery of the connecting pad, so that the periphery of the connecting pad can be protected from being corroded by the manufacturing process or the testing environment. In addition, the current stress resistance of the signal line can be improved by connecting the transparent conductive wire for bridging the connection pad by using the widened end width part of the signal line.

Although the present invention has been described with reference to the above embodiments, it should be understood that the invention is not limited thereto, but rather is capable of modification and variation without departing from the spirit and scope of the present invention.

Claims

1. A touch display device is provided with a display area and a peripheral area, and comprises:

a substrate;

a signal line on the substrate and extending from the display region to the peripheral region;

the connecting pad is positioned in the peripheral area and is electrically connected with the signal wire; and

the protection layer is positioned on the signal wire and the connecting pad, is provided with a through hole overlapping the connecting pad and comprises a flat part and an annular hole part, wherein the flat part surrounds the annular hole part and is provided with a first height, the annular hole part forms the side wall of the through hole and is provided with a second height, the first height is larger than the second height, the upper surface and the side wall of the flat part, the upper surface of the annular hole part and the side wall of the through hole form a step shape, and the upper surface of the annular hole part is closer to the substrate than the upper surface of the flat part.

2. The touch display device of claim 1, wherein a difference between the second height and the height of the bonding pad is less than or equal to 0.8 μm.

3. The touch display device of claim 1, wherein the pad comprises a single-layer or multi-layer structure.

4. The touch display device of claim 3, wherein the pad comprises a first conductive layer and a second conductive layer, the second conductive layer completely covers the first conductive layer, and the sidewall of the via completely covers a periphery of the second conductive layer.

5. The touch display device of claim 4, wherein the signal lines comprise a first signal line and a second signal line, and the first conductive layer and the first signal line belong to the same film layer, and the second conductive layer and the second signal line belong to the same film layer.

6. The touch display device of claim 5, further comprising a transfer wire, wherein the transfer wire electrically connects the second signal line and the first conductive layer, and the transfer wire and the first signal line belong to the same film layer.

7. The touch display device of claim 6, wherein the second signal line is electrically connected to the transfer wire through a via.

8. The touch display device of claim 1, wherein the protective layer is formed by a phase transfer photomask, a semi-tone photomask, or a gray-scale photomask fabrication process.

9. The touch display device of claim 1, wherein the signal line is separate from the pad.

10. The touch display device of claim 9, wherein the signal line bridges the pads through transparent conductive lines.

11. The touch display device of claim 10, wherein the protective layer comprises an organic material.

12. The touch display device of claim 10, wherein the signal line includes an end wide portion overlapping the transparent conductive line, and a line width of the end wide portion is smaller than a line width of the transparent conductive line.

13. The touch display device of claim 12, wherein a difference between a line width of the transparent conductive line and a line width of the end wide portion is greater than or equal to 6 μm.

14. The touch display device of claim 12, wherein a line width of the end wide portion is greater than a line width of the signal line in the display area.

15. The touch display device of claim 12, further comprising a polarizer covering the signal line and a portion of the transparent conductive line, wherein a distance between the end-wide portion and an edge of the polarizer is greater than or equal to 500 μm.