TWI416397B - Touch panel, formation method thereof and display device containing the same - Google Patents

Abstract

A touch panel is provided. The touch panel has an active area and a frame area, wherein the active area is surrounded by the frame area. The touch panel includes a patterned first conductive layer disposed on the active area of a substrate. A light shielding layer has a first portion and a second portion, wherein the first portion is disposed on the patterned first conductive layer and the second portion is disposed on the frame area of the substrate. A patterned second conductive layer is disposed on the light shielding layer. Then, a protective layer is formed to fully cover the substrate.

Description

Touch panel, method of forming the same, and touch display device

The present invention relates to a touch panel, and more particularly to a capacitive sensing external touch panel.

The current touch panel can achieve the effect of touch sensing by using a resistive type, a capacitive type or other methods, such as infrared rays or surface acoustic waves, wherein the capacitive touch panel is used to monitor a user's finger or a stylus and a capacitive type. The capacitance value generated between the touch sensing electrodes determines the position of the touch, because the capacitive touch panel can achieve the touch effect without applying pressure, which is the mainstream of the future development of the touch panel.

Currently, the capacitive touch panel can be divided into two types, one is an add on touch panel, and the capacitive touch panel is externally applied to the display panel, but the touch panel needs two pieces of glass. The substrate is composed of a glass substrate for forming a capacitive touch element thereon, and another glass substrate for protecting the outer cover of the capacitive touch element. Therefore, the touch panel may increase the overall thickness of the touch display device. .

Another type of touch panel is formed on the back surface of a color filter (CF) substrate of the display panel (on CF), and then a piece of glass substrate is used as a protective capacitive touch element. The cover, although the touch panel can reduce the use of a glass substrate, the first fabricated capacitive touch element is easily scratched in the double-sided process of the subsequent color filter substrate.

Therefore, there is a need in the industry for a touch panel that overcomes the above problems, that is, the use of only one glass substrate to complete the fabrication of the touch panel, thereby reducing the overall thickness of the touch display device and reducing the cost of a glass substrate. It can reduce the number of processes of the touch panel.

According to an embodiment of the invention, there is provided a touch panel having an action area and a frame area, wherein the frame area surrounds the action area, the touch panel includes: a substrate, and the patterned first conductive layer is disposed on the action area of the substrate The shielding layer has a first portion and a second portion, wherein the first portion is disposed on the patterned first conductive layer, the second portion is disposed on the frame region of the substrate, and the patterned second conductive layer is disposed on the shielding layer And the protective layer is completely covered on the substrate.

According to an embodiment of the present invention, a touch display device includes the touch panel as described above, and the display panel is disposed under the touch panel, wherein the protective layer of the touch panel is adjacent to the display surface of the display panel.

In addition, according to an embodiment of the invention, a method for forming a touch panel includes: providing a substrate, the substrate being divided into an action area and a frame area, wherein the frame area surrounds the action area; forming a patterned first conductive layer on the substrate Forming a masking layer on the patterned first conductive layer and the frame region of the substrate; forming a patterned second conductive layer on the patterned shielding layer; and forming a protective layer covering the substrate in a comprehensive manner on.

In order to make the above objects, features, and advantages of the present invention more comprehensible, the following detailed description is made in conjunction with the accompanying drawings.

An embodiment of the present invention provides a capacitive sensing external touch panel, which is formed on a cover lens of a touch panel and covered with a protective layer in a capacitive touch. The control of the sensing electrode can reduce the use of a glass substrate, reduce the overall thickness of the touch display device, and save the cost of a glass substrate.

In addition, according to the method for manufacturing a touch panel according to an embodiment of the invention, the number of processes required for manufacturing the touch panel can be reduced, the manufacturing cost of the touch panel can be reduced, and the production yield can be improved. In the meantime, the touch panel according to an embodiment of the invention can avoid the problem of reflection caused by the metal bridge structure of the capacitive touch sensing electrode.

Please refer to FIG. 1 , which is a plan view showing a touch panel according to an embodiment of the present invention. The touch panel 100 has an active area 100A and a frame area 100B, wherein the frame area 100B surrounds the action area 100A. In the action area 100A of the touch panel 100, there are a plurality of capacitive touch sensing electrodes 104a and 104b, which are island-shaped transparent conductive layers, for example, diamond-shaped indium tin oxide (ITO) layers, although Only eight capacitive touch sensing electrodes 104a and 104b are shown in FIG. 1. However, those skilled in the art can understand that there are more capacitive touches in the action area 100A of the touch panel 100. The sensing electrodes 104a and 104b are controlled, wherein the electrodes 104a are arranged in series in a row, and the electrodes 104b are arranged in series in a row. In one embodiment, the electrodes 104b of the same row are directly connected by a transparent conductive layer forming the capacitive touch sensing electrodes 104a and 104b, and the electrodes 104a of the same row are electrically connected by the conductive bridge structure 108b, each row. The touch signals obtained by the capacitive touch sensing electrodes 104a and 104b of each column can be transmitted to a flexible printed circuit (FPC) (not shown) through the wire structure 108a, and then transmitted to the flexible circuit board through the flexible circuit board. The integrated circuit (IC) (not shown) in the touch display device performs processing of the touch signal.

According to an embodiment of the present invention, an island type shielding layer 106b is disposed between the bridging structure 108b and the capacitive touch sensing electrodes 104a and 104b to prevent the electrodes 104b of the same row from intersecting the electrodes 104a of the same row. A short circuit occurs and the position of the island-shaped shielding layer 106b corresponds to the position of the bridge structure 108b. In an embodiment, the island-shaped shielding layer 106b located in the action area 100A and the shielding layer 106a located in the frame area 100B may be simultaneously formed using the same material, and the material of the shielding layers 106b and 106a is an insulating light-shielding material, for example, a black insulating light-shielding material. a color insulating light-shielding material or a white insulating light-shielding material, the insulating light-shielding material may be a photosensitive material, for example, a black photoresist, so that the island-shaped shielding layer 106b and the shielding layer 106a of the frame region 100B can be simultaneously exposed and developed. form.

Referring to FIG. 2, there is shown a cross-sectional view of a touch panel according to an embodiment of the present invention along a section line 2-2' of FIG. The touch panel 100 includes a transparent substrate 102 as a protective cover of the touch panel 100 , such as a glass substrate or a plastic substrate. When the user's finger or stylus 120 contacts the touch panel 100 , the substrate 102 can be The sensing electrodes 104a and 104b of the touch panel 100 are protected to prevent the sensing electrodes 104a and 104b from being scratched by the finger or the stylus 120.

Meanwhile, please refer to FIGS. 6A to 6D, which are cross-sectional views showing a method of manufacturing the touch panel 100 of FIG. 2 according to an embodiment of the present invention. As shown in FIG. 6A, a patterned first conductive layer 104a is first formed on the substrate 102 as a capacitive touch sensing electrode. Although the electrode 104b is not shown in FIG. 6A (as shown in FIG. 1), the capacitive touch sensing electrodes 104b and 104a are simultaneously formed, and the process steps include depositing a transparent first conductive layer (not shown). For example, an indium tin oxide layer, and then the first conductive layer is patterned by a lithography and etching process to form island-shaped capacitive touch sensing electrodes 104b and 104a. In one embodiment, the electrodes 104b of the same row are mutually The electrodes 104a of the same column are connected to each other.

Referring to FIG. 6B, a patterned shielding layer 106a is formed on the frame region 100B of the substrate 102, while a patterned shielding layer 106b is formed on the active region 100A of the substrate 102, wherein the shielding layer 106a is a frame surrounding the action region 100A. The shielding layer 106b is an island between any two adjacent capacitive touch sensing electrodes 104a in the same column, and a portion of the shielding layer 106b covers the capacitive touch sensing electrode 104a. As shown in FIG. 1, the size of the island-shaped shielding layer 106b is smaller than the size of the capacitive touch sensing electrodes 104a and 104b. In one embodiment, the material of the shielding layers 106a and 106b is a photosensitive insulating light-shielding material, such as a black photoresist, so that the patterned shielding layers 106a and 106b can be simultaneously formed by an exposure and development process.

Referring to FIG. 6C, patterned second conductive layers 108a and 108b are formed on the patterned shielding layers 106a and 106b, respectively, wherein the patterned second conductive layer 108a serves as the wires of the capacitive touch sensing electrodes 104a and 104b. The structure is configured to transmit the touch signals of the electrodes 104a and 104b, and the patterned second conductive layer 108b serves as a bridge structure between the capacitive touch sensing electrodes 104a, thereby electrically connecting any two phases in the same column. Adjacent sensing electrode 104a.

In an embodiment, the patterned second conductive layers 108a and 108b may be formed of the same material, such as a metal material, by first depositing a metal layer, and then patterning the metal layer by using a lithography and etching process. Patterned second conductive layers 108a and 108b are formed.

In another embodiment, the patterned second conductive layers 108a and 108b may be formed of different materials, for example, the patterned second conductive layer 108a may be formed of a metal material, and the patterned second conductive layer 108b may be a transparent conductive material. form. In an embodiment, as shown in FIG. 1, the patterned second conductive layer 108b may have a smaller size than the patterned mask layer 106b. In another embodiment, the size of the patterned second conductive layer 108b may be equal to the size of the patterned mask layer 106b.

Referring to FIG. 6D, the protective layer 110 is formed over the substrate 102 in a comprehensive manner to complete the fabrication of the touch panel 100 as shown in FIG. The material of the protective layer 110 is, for example, a material such as an acrylic resin, tantalum nitride, cerium oxide or cerium oxynitride. The protective layer 110 directly covers the patterned second conductive layers 108a and 108b, the patterned shielding layers 106a and 106b, the patterned first conductive layers (capacitive sensing electrodes) 104a and 104b, and the substrate 102.

Next, please refer to FIG. 3, which is a cross-sectional view showing a touch display device 300 according to an embodiment of the present invention. The touch display device 300 includes the touch panel 100 of the second embodiment and the display panel 200 . The protective layer 110 of the touch panel 100 is attached to the display surface 200A side of the display panel 200 adjacent to the upper substrate 202 of the display panel 200 . In an embodiment, the display panel 200 may be a liquid crystal display panel including an upper substrate 202, a lower substrate 204, and a liquid crystal layer 206 interposed between the upper substrate 202 and the lower substrate 204. The upper substrate 202 is, for example, a color filter substrate, and the lower substrate 204 is, for example, a thin film transistor array substrate. As is known to those skilled in the art, the touch display device 300 may further include other components, such as a backlight (not shown) disposed under the display panel 200, attached to the upper substrate 202 and the lower substrate 204. A pair of outer polarizers (not shown), and an adhesive layer (not shown) disposed between the touch panel 100 and the display panel 200.

In addition, please refer to FIG. 4 , which is a schematic cross-sectional view of a touch display device 400 that is well known to the inventors. As shown in FIG. 4 , the touch display device 400 includes a touch panel 10A and a display panel 200 . The touch panel 10A is formed by two glass substrates 12 and 24 , and a capacitive touch sensor is formed on the glass substrate 12 . The electrode 14 has an isolation layer 16 between two adjacent capacitive touch sensing electrodes 14 , and then has a metal layer 18 on the isolation layer 16 as a bridging structure between the capacitive touch sensing electrodes 14 , and electrically connected Adjacent capacitive sensing electrodes 14 and covering the insulating layer 20 on the glass substrate 12, and then providing a glass substrate 24 having a black frame 22 formed thereon as a protective cover attached to the isolation layer 20, The production of the touch panel 10A.

In contrast to the touch panel 100 of the embodiment of the present invention, the touch panel 100 of the embodiment of the present invention can reduce the use of a glass substrate. In addition, the touch panel 10A of FIG. 4 requires five masks, two deposition processes, five lithography processes, and two etching processes to complete the black frame 22, the capacitive touch sensing electrodes 14, and the isolation layers 16 and 20. And the fabrication of the metal bridge 18; and the touch panel 100 of the embodiment of the present invention requires only four masks, two deposition processes, four lithography processes, and two etching processes to complete the first patterning. Conductive layers (capacitive sensing electrodes) 104a and 104b, patterned shielding layers 106a and 106b, patterned second conductive layers 108a and 108b, and fabrication of protective layer 110. Therefore, the number of processes of the touch panel 100 according to an embodiment of the present invention can be reduced by one mask and one lithography process compared to the number of processes of the touch panel 10A of FIG.

In addition, the touch panel 100 according to an embodiment of the present invention has a position that the island-shaped shielding layer 106b corresponds to the bridging structure 108b, so that the problem of reflection of the metal bridging structure 108b can be solved; and the metal bridge in the touch panel 10A of FIG. 18 will have a reflective problem.

Next, please refer to FIG. 5, which is a cross-sectional view showing another touch display device 500 well known to the inventors. As shown in FIG. 5 , the touch display device 500 includes a touch panel 10B and a display panel 200 . The touch panel 10B includes a glass substrate 24 as a protective cover, and a black frame 22 is formed on the glass substrate 24 in the black frame. A transparent conductive layer 26 is formed on the 22 as a bridging structure of the capacitive touch sensing electrode 30, and then an isolation layer 28 is formed to cover the transparent conductive layer 26 and the black frame 22. Then, the sensing electrode 30 and the metal wiring layer 32 are formed on the isolation layer 28. The isolation layer 34 is formed to cover the sensing electrode 30 and the metal wiring layer 32 to complete the fabrication of the touch panel 10B.

In contrast to the touch panel 100 of the embodiment of the present invention, the touch panel 10B of FIG. 5 requires six masks, four deposition processes, six lithography processes, and four. The etch process is performed to complete the fabrication of the black frame 22, the transparent conductive layer 26, the isolation layers 28 and 34, the capacitive sensing electrode 30, and the metal wiring layer 32. The touch panel 100 of the embodiment of the present invention requires only 4 lights. The patterned first conductive layer (capacitive sensing electrodes) 104a and 104b, the patterned shielding layers 106a and 106b, and patterned are completed by a mask, a secondary deposition process, a 4-time lithography process, and a second etching process. The second conductive layers 108a and 108b, and the fabrication of the protective layer 110. Therefore, the number of processes of the touch panel 100 according to an embodiment of the present invention can be reduced by two masks, two deposition processes, two lithography processes, and two etching processes compared to the number of processes of the touch panel 10B of FIG. Process.

In summary, the touch panel of the embodiment of the present invention has a capacitive touch sensing electrode formed on the protective cover of the touch panel, thereby integrating the functions of the capacitive touch sensing electrode and the protective cover. On the same substrate, the overall thickness of the touch display device is reduced, and the cost of one substrate is reduced.

In addition, compared with the current manufacturing method of the touch panel, the manufacturing method of the touch panel of the embodiment of the present invention can reduce the number of processes, thereby reducing the manufacturing cost of the touch panel and improving the production yield. At the same time, the touch panel of the embodiment of the invention can also solve the problem of reflection caused by the metal bridge of the capacitive touch sensing electrode.

Although the present invention has been disclosed in its preferred embodiments, it is not intended to limit the invention, and the invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection is subject to the definition of the scope of the patent application attached.

100, 10A, 10B. . . Touch panel

100A. . . Action zone

100B. . . Frame area

102. . . Substrate

104a, 104b. . . Patterned first conductive layer (capacitive sensing electrode)

106a, 106b. . . Patterned masking layer

108a, 108b. . . Patterning the second conductive layer

110. . . The protective layer

120. . . Finger or stylus

200. . . Display panel

200A. . . Display surface

202. . . Color filter substrate

204. . . Thin film transistor array substrate

206. . . Liquid crystal layer

12, 24. . . glass substrate

14, 30. . . Capacitive sensing electrode

16, 20, 28, 34. . . Isolation layer

18. . . Metal layer (bridge structure)

twenty two. . . Black frame

26. . . Transparent conductive layer (bridge structure)

32. . . Wire layer

300, 400, 500. . . Touch display device

1 is a schematic plan view showing a touch panel according to an embodiment of the invention.

Fig. 2 is a cross-sectional view showing a touch panel according to an embodiment of the present invention, taken along line 2-2' of Fig. 1.

3 is a cross-sectional view showing a touch display device in accordance with an embodiment of the present invention.

Figure 4 is a schematic cross-sectional view showing a touch display device well known to the inventors.

Figure 5 is a schematic cross-sectional view showing another touch display device known to the inventors.

6A to 6D are cross-sectional views showing a method of manufacturing the touch panel 100 of Fig. 2 according to an embodiment of the present invention.

100‧‧‧ touch panel

100A‧‧‧ action area

100B‧‧‧Frame Zone

102‧‧‧Substrate

104a‧‧‧ patterned first conductive layer (capacitive touch sensing electrode)

106a, 106b‧‧‧ patterned masking layer

108a, 108b‧‧‧ patterned second conductive layer

110‧‧‧Protective layer

120‧‧‧Finger or stylus

Claims (20)

A touch panel has an action area and a frame area, the frame area surrounds the action area, the touch panel includes: a substrate; a patterned first conductive layer disposed in the action area of the substrate; The layer has a first portion and a second portion, wherein the first portion is disposed on the patterned first conductive layer, the second portion is disposed on the frame region of the substrate; and a patterned second conductive portion a layer disposed on the shielding layer; and a protective layer covering the substrate in a comprehensive and planar manner. The touch panel of claim 1, wherein the material of the shielding layer is one of a black insulating light-shielding material, a color insulating light-shielding material or a white insulating light-shielding material or a combination thereof. The touch panel of claim 1, wherein the patterned first conductive layer comprises a plurality of first islands, the first portion of the shielding layer comprises a plurality of second islands, and Wherein the second island is disposed between the two adjacent first islands in the same column or the same row. The touch panel of claim 3, wherein the size of the second island is smaller than the size of the first island. The touch panel of claim 1, wherein the material of the patterned first conductive layer comprises a transparent conductive material. The touch panel of claim 1, wherein the patterned second conductive layer comprises a bridge structure and a wire structure, the bridge structure is disposed on the first portion of the shielding layer, the wire structure Provided on the second portion of the shielding layer, and wherein the size of the bridging structure is smaller than Or equal to the size of the first portion of the shielding layer. The touch panel of claim 6, wherein the material of the bridge structure comprises a transparent conductive material or a metal material, and the material of the wire structure comprises a metal material. The touch panel of claim 1, wherein the protective layer directly covers the patterned second conductive layer, the patterned first conductive layer, the shielding layer, and the substrate. The touch panel of claim 1, wherein the substrate is closer to a user's touch position than the protective layer. A touch display device includes: a touch panel as described in claim 1; and a display panel disposed under the touch panel, wherein the protective layer of the touch panel is adjacent to the display panel . A method for forming a touch panel, comprising: providing a substrate having an action area and a frame area, wherein the frame area surrounds the action area; forming a patterned first conductive layer on the action area of the substrate; forming a patterned shielding layer on the patterned first conductive layer and the frame region of the substrate; forming a patterned second conductive layer on the patterned shielding layer; and forming a protective layer, comprehensive and planarized The ground is overlaid on the substrate. The method of forming a touch panel according to claim 11, wherein the step of forming the patterned first conductive layer and the patterned second conductive layer comprises a deposition, a lithography, and an etching process. The method of forming a touch panel according to claim 11, wherein the step of forming the patterned mask layer comprises a lithography process. The method of forming a touch panel according to claim 11, wherein the step of forming the patterned shielding layer is performed after the step of forming the patterned first conductive layer, and forming the patterned second conductive layer The step is performed after the step of forming the patterned masking layer. The method for forming a touch panel according to claim 11, wherein the material of the patterned shielding layer is one of a black insulating light-shielding material, a color insulating light-shielding material or a white insulating light-shielding material or a combination thereof. The method of forming a touch panel according to claim 11, wherein the patterned first conductive layer comprises a plurality of first islands, the patterned shielding layer comprising a plurality of second islands and a frame And wherein the second island is disposed between the two adjacent first islands in the same column or the same row. The method of forming a touch panel according to claim 16, wherein the size of the second island is smaller than the size of the first island. The method for forming a touch panel according to claim 16, wherein the patterned second conductive layer comprises a bridge structure and a wire structure, and the bridge structure is disposed on the second islands of the patterned shielding layer. The wire structure is disposed on the frame of the patterned shielding layer, and wherein the size of the bridge structure is less than or equal to the size of one of the second islands. The method for forming a touch panel according to claim 18, wherein the material of the patterned first conductive layer comprises a transparent conductive material, and the material of the bridge structure of the patterned second conductive layer comprises a transparent A conductive material or a metal material, and the material of the wire structure comprises a metal material. The method of forming a touch panel according to claim 11, wherein the protective layer directly covers the patterned second conductive layer, the patterned first conductive layer, the patterned shielding layer, and the substrate.