KR20190094877A - Touch sensor and image display device including the same - Google Patents

Abstract

According to embodiments of the present invention, a touch sensor comprises: a basic material layer; a first conductive pattern formed on the basic material layer and including first sensing electrodes and first wires branched from each of the first sensing electrodes and extending; and a second conductive pattern spaced apart from the first conductive pattern, disposed on top of the first conductive pattern, and including second sensing electrodes and second wires branched from each of the second sensing electrodes and extending. By forming the second conductive pattern on top of the first conductive pattern, an inactive area due to the wires may be reduced.

Description

TOUCH SENSOR AND IMAGE DISPLAY DEVICE INCLUDING THE SAME}

The present invention relates to a touch sensor and an image display device including the same. More particularly, the present invention relates to a touch sensor including a patterned sensing electrode and an image display device including the same.

Recently, with the development of the information society, the demand for the display field is also presented in various forms. For example, a flat panel display device having features such as thinness, light weight, and low power consumption, for example, a liquid crystal display device, a plasma display panel device, Electro luminescent display devices and organic light-emitting diode display devices have been studied.

Meanwhile, a touch panel or a touch sensor, which is an input device attached to the display device and inputs a user's command by selecting an instruction displayed on the screen with a human hand or an object, is combined with a display device to display an image display function Electronic devices in which information input functions are implemented are being developed.

In addition, as the resolution of the display device is improved to a level such as quad high definition (QHD), ultra high definition (UHD), and the like, the resolution and sensing sensitivity of the touch sensor also need to be increased.

In order to improve sensing sensitivity of the touch sensor, the number of sensing electrodes per unit area may be increased, and in this case, the number of wires (or traces) connected to each sensing electrode may be increased. Therefore, as the number of wires increases, the area where the sensing electrode may be formed may be reduced, and the touch sensing failure may be caused by the increase in the non-sensing area (inactive area).

For example, as disclosed in Korean Patent Application Publication No. 2014-0092366, a touch screen panel in which a touch sensor is coupled to various image display devices has recently been developed. However, as described above, a touch sensor or a touch panel having high integration and high resolution is required. Is continuing.

Korean Patent Publication No. 2014-0092366

One object of the present invention is to provide a touch sensor having improved resolution and sensitivity.

One object of the present invention is to provide an image display device including a touch sensor having improved resolution and sensitivity.

1. Base material layer; A first conductive pattern formed on the base layer and including first wirings and first wirings branching from the first sensing electrodes, respectively; And a second conductive pattern spaced apart from the first conductive pattern and disposed on the first conductive pattern, the second conductive pattern including second wirings and second wirings branching from and extending from the second sensing electrodes, respectively. , Touch sensor.

2. In the above 1, wherein the second sensing electrodes overlap the first wirings in the thickness direction of the touch sensor, the touch sensor.

3. In the above 1, wherein the first sensing electrodes are arranged in a first direction parallel to the upper surface of the base layer to form a first sensing electrode column, a plurality of first sensing electrode rows of the base layer Are arranged along a second direction parallel to the top surface and intersecting the first direction,

And the second sensing electrodes are arranged along the first direction to form a second sensing electrode row, and the plurality of second sensing electrode rows are arranged along the second direction.

4. The touch sensor of 3 above, wherein the first sensing electrode columns and the second sensing electrode columns are alternately arranged alternately on the same plane.

5. The touch sensor of claim 4, wherein the second sensing electrode column overlaps the first wires connected to the adjacent first sensing electrode column on the same plane.

6. The touch sensor of claim 4, wherein the second wires connected to the second sensing electrode column overlap the first sensing electrode column on the same plane.

7. In the above 1, further comprising an insulating layer covering the first conductive pattern on the base layer, the second conductive pattern is disposed on the insulating layer, the touch sensor.

8. The touch sensor according to the above 7, further comprising a passivation layer covering the second conductive pattern on the insulating layer.

9. The touch sensor of claim 8, wherein the insulating layer and the passivation layer include a first opening exposing end portions of the first wires and second openings exposing end portions of the second wires.

10. The touch sensor of claim 9, further comprising a first pad layer formed on the end portions of the first wires, and a second pad layer formed on the end portions of the second wires.

11. The touch sensor of claim 10, wherein the first wires and the second wires include a transparent conductive oxide, and the first pad layer and the second pad layer include metal.

12. The touch sensor of claim 9, wherein the end portions of the first wires and the second wires are located on the same layer or the same level.

13. In the above 1, the magnetic capacitive touch sensor.

14. The touch sensor of claim 13, wherein the first sensing electrodes and the second sensing electrodes each have an independent island pattern.

15. Image display device comprising the touch sensor of any one of the above 1 to 14.

The touch sensor according to the embodiments of the present invention may include a lower conductive pattern and an upper conductive pattern, and the lower conductive pattern and the upper conductive pattern may include a lower sensing electrode and an upper sensing electrode, respectively. Since the sensing electrodes are arranged in different layers or levels, the spaces occupied by the wirings may also be distributed in different layers or levels.

Therefore, the area of the sensing area can be increased by reducing the area occupied by the wirings per unit plane while maintaining high integration.

The upper electrode may be disposed to overlap the wires connected to the lower electrode on a plane, and thus may significantly reduce the distance or space between the lower electrode and the upper electrode on the plane.

Accordingly, the sensing sensitivity is improved by reducing the area of the non-active area, extending the sensing area, and a high resolution sensing operation can be implemented without disconnection or failure of the sensing signal even when a multi-touch or a drawing touch is input.

1 and 2 are schematic cross-sectional views and plan views respectively illustrating touch sensors according to exemplary embodiments.
3 is a schematic plan view for describing a touch sensor according to a comparative example.
4 through 6 are schematic cross-sectional views illustrating pad areas of a touch sensor according to example embodiments.

Embodiments of the present invention provide a touch sensor including sensing electrodes and wires distributed over a plurality of layers. In addition, an image display device including the touch sensor is provided.

Hereinafter, exemplary embodiments of the present invention will be described in more detail with reference to the accompanying drawings. However, the following drawings attached to the present specification are intended to illustrate preferred embodiments of the present invention, and together with the contents of the present invention serves to further understand the technical spirit of the present invention, the present invention described in such drawings It should not be construed as limited to matters.

In the following drawings, two directions that are parallel to the same plane (eg, the substrate layer upper surface) and intersect, for example, perpendicularly to each other, are defined as the first direction and the second direction, respectively.

1 and 2 are schematic cross-sectional views and plan views respectively illustrating touch sensors according to exemplary embodiments. For convenience of description, the illustration of the insulating layer 120 and the passivation layer 140 shown in FIG. 1 is omitted.

1 and 2, the touch sensor of the exemplary embodiments may include a base layer 100, a first conductive pattern 110 (eg, a lower conductive pattern), and a second conductive pattern 130 (eg, For example, the upper conductive pattern may be included. The second conductive pattern 130 may be disposed on the first conductive pattern 110 and spaced apart from the first conductive pattern 110 in a vertical direction (or a thickness direction).

The substrate layer 100 may be a substrate, or a film material, which is commonly used for a touch sensor, without particular limitation, and may include, for example, glass, a polymer, and / or an inorganic insulating material. Examples of the polymer include cyclic olefin polymer (COP), polyethylene terephthalate (PET), polyacrylate (PAR), polyetherimide (PEI), polyethylene naphthalate (PEN), polyphenylene sulfide (PPS), poly Polyallylate, polyimide (PI), cellulose acetate propionate (CAP), polyethersulfone (PES), cellulose triacetate (TAC), polycarbonate (PC), cyclic olefin copolymer (COC), poly Methyl methacrylate (PMMA) etc. are mentioned. Examples of the inorganic insulating material include silicon oxide, silicon nitride, silicon oxynitride, metal oxides, and the like.

In some embodiments, the base layer 100 may refer to a display panel of a display device in which a touch sensor is stacked. In addition, the base layer 100 may mean an optical layer or an optical film included in the display device such as a retarder, a polarizing plate, a hard coating layer.

The first conductive pattern 110 may be disposed on the substrate layer 100. In some embodiments, the first conductive pattern 110 may directly contact the top surface of the base layer 100.

As illustrated in FIG. 2, the first conductive pattern 110 may include first sensing electrodes 112 and first wires 114.

The plurality of first sensing electrodes 112 (112a, 112b, 112c, and 112d) may be arranged along the first direction to form a first sensing electrode column. The plurality of first sensing electrode columns may be spaced apart from each other along the second direction.

In example embodiments, the first wirings 114a, 114b, 114c, and 114d may branch and extend from each of the first sensing electrodes 112a, 112b, 112c, and 112d.

For example, as shown in FIG. 2, each of the first wires 114 may be branched from each of the first sensing electrodes 112 in the second direction and then bent to extend in the first direction.

The first conductive pattern 110 may include a transparent conductive oxide or a metal. The transparent conductive oxide may include, for example, indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium zinc oxide (IZTO), cadmium tin oxide (CTO), or the like. The metal is, for example, silver (Ag), gold (Au), copper (Cu), aluminum (Al), platinum (Pt), palladium (Pd), chromium (Cr), titanium (Ti), tungsten (W). ), Niobium (Nb), tantalum (Ta), vanadium (V), iron (Fe), manganese (Mn), cobalt (Co), nickel (Ni), zinc (Zn), or alloys thereof. have.

In some embodiments, the first conductive pattern 110 may be formed to include the transparent conductive oxide to secure transparency or transmittance of the sensing electrode. In some embodiments, the first conductive pattern 110 may be formed of a multilayer structure of a transparent conductive oxide layer and a metal layer for low resistance and sensing sensitivity of the sensing electrode.

The first conductive pattern 110 may be formed on the base layer 100 by forming a first conductive layer including the above-described transparent conductive oxide and / or metal, and then, for example, by using a patterning process using a photolithography process. The first conductive pattern 110 may be formed from the first conductive layer.

In some embodiments, the first sensing electrodes 112 and the first wirings 114 may be formed at the same time through a single etching process of the first conductive layer.

Referring back to FIG. 1, an insulating layer 120 may be formed on the substrate 100 to cover the first conductive patterns 110. The insulating layer 120 may include an inorganic insulating material such as silicon oxide, silicon nitride, or the like, and / or an organic insulating material such as an acrylic resin, a siloxane resin, or the like.

The second conductive pattern 130 may be formed on the insulating layer 120 by forming a second conductive layer including the transparent conductive oxide and / or metal described above, and then may be substantially patterned to form the first conductive pattern 110. Can be formed through the same or similar process. Accordingly, the second conductive pattern 130 may include second sensing electrodes 132 and second wires 134.

The plurality of second sensing electrodes 132 (132a, 132b, 132c, and 132d) may be arranged along the first direction to form a second sensing electrode column. The plurality of second sensing electrode columns may be spaced apart from each other along the second direction.

According to example embodiments, the second wires 134a, 134b, 134c, and 134d may branch and extend from each of the second sensing electrodes 132a, 132b, 132c, and 132d.

For example, as shown in FIG. 2, each second wire 134 may branch from the second sensing electrode 132 in the second direction and bend to extend in the first direction.

As illustrated in FIG. 2, the first sensing electrode columns and the second sensing electrode columns may be alternately arranged along the second direction on a plane. The second sensing electrode column may be disposed between the neighboring first sensing electrode columns and overlap the first wires 114 connected to one first sensing electrode column. In FIG. 2, the first wires 114 are shown by dotted lines to indicate that the second sensing electrode column (or the second sensing electrodes 132) overlap the first wires 114.

Second wirings 134 connected to the second sensing electrode column may be disposed on the first sensing electrode column, and overlap the first sensing electrode column (or the first sensing electrodes 112) on a plane. have.

Accordingly, as shown in FIG. 1, the first conductive pattern 110 and the second conductive pattern 130 may be alternately arranged along the second direction in the cross section of the thickness direction of the touch sensor. In addition, the second conductive pattern 130 may partially overlap the first conductive pattern 110 in the thickness direction. In some embodiments, the second conductive pattern 130 may partially overlap with two neighboring first conductive patterns 110.

The passivation layer 140 may be formed on the insulating layer 120 to cover the second conductive patterns 130. The passivation layer 140 may protect the second conductive pattern 130 from external moisture or external impact.

For example, the passivation layer 140 may include an inorganic insulating material such as silicon oxide, silicon nitride, and / or an organic insulating material such as acrylic resin, siloxane resin, or the like.

According to the exemplary embodiments described above, the first conductive pattern 110 and the second conductive pattern 130 may be formed on different layers or at different levels using the insulating layer 120. Therefore, by minimizing the horizontal separation distance between the sensing electrodes (112, 132) it is possible to significantly reduce the area of the inactive area that does not include the sensing electrode.

Therefore, sensing sensitivity and resolution are increased, and continuity and reliability of touch signal transmission can be improved.

In the touch sensor according to the exemplary embodiments, each sensing electrode 112 and 132 may be independently disposed in an island form, and wires 114 and 134 may be connected to each sensing electrode 112 and 132. For example, the touch sensor may be a self-capacitance touch sensor.

Thus, for example, compared to a mutual capacitive touch sensor in which a plurality of sensing electrodes are connected to each other and arranged to cross each other in the X and Y directions, the amount of signal interference and signal noise may be reduced.

In FIGS. 1 and 2, sensing electrodes and wires of the touch sensor are distributed in two layers or levels, but may be distributed in three or more layers or levels.

3 is a schematic plan view for describing a touch sensor according to a comparative example.

Referring to FIG. 3, the touch sensor of the comparative example includes sensing electrodes 212 arranged on an upper surface of the base layer 100, and includes wirings 214 branched from each sensing electrode 212. .

A plurality of sensing electrodes 212; 212a, 212b, 212c, and 212d are arranged along the first direction on the base layer 100 to form a sensing electrode column, and the plurality of sensing electrode columns may be arranged in the second direction. Can be arranged spaced apart from one another.

According to a comparative example, the sensing electrodes 212 or the sensing electrode columns are disposed on the same plane or on the same level, and thus the wirings 214 are also arranged on the same plane as the sensing electrodes 212. Accordingly, as shown in FIG. 3, the wirings 214 are disposed between neighboring sensing electrode columns, thereby increasing the area of the inactive region NA.

In the touch sensor of the comparative example, for example, when a drawing touch of a finger is input along the second direction, signal disconnection may occur as non-active regions NA exist between the sensing electrode columns. . In addition, even in a multi-touch input where a plurality of points are touched, each of the spaced sensing electrodes 212 acts as a domain, and thus it is difficult to implement a signal generation.

However, in the exemplary embodiments according to the exemplary embodiments described with reference to FIGS. 1 and 2, the sensing electrodes may be disposed on a plurality of levels to significantly reduce the area of the inactive region occupied by the wirings. Accordingly, as the sensing electrode density increases, reliable signal generation for the above-described drawing touch and multi-touch can be effectively implemented along with improvement of sensing sensitivity and resolution.

4 through 6 are schematic cross-sectional views illustrating pad areas of a touch sensor according to example embodiments.

For example, FIG. 4 is a cross-sectional view of the pad region of the touch sensor of FIGS. 1 and 2 taken along the second direction. 5 is a cross-sectional view in a first direction with respect to a pad area connected to the first wires 114. FIG. 6 is a cross-sectional view in a first direction with respect to the pad area connected to the second wires 134.

4 to 6, the first wires 114 and the second wires 134 shown in FIG. 2 are one of the touch sensors including, for example, the pad area along the first direction. It may extend to the end.

First openings 152 and second openings 154 exposing the first wirings 114 and the second wirings 134 may be formed on the pad region, respectively. External circuit members such as, for example, flexible printed circuit boards (FPCBs) are electrically connected to the first wirings 114 and the second wirings 134 through the first openings 152 and the second openings 154, respectively. Can be connected.

In some embodiments, an intermediate conductive material such as an anisotropic conductive film or conductive paste filling the first openings 152 and the second openings 154 and connected to the first wirings 114 and the second wirings 134. A structure is formed, and the flexible circuit board can be attached on the intermediate conductive structure.

The first opening 152 and the second opening 154 may be formed by partially etching or removing the passivation layer 140 and the insulating layer 120, respectively.

As illustrated in FIG. 4, the plurality of first lines 114 may be exposed through the first opening 152, and the plurality of second lines 134 may be exposed through the second opening 154. have.

In some embodiments, pad layers 116 and 136 including metal may be formed on the wirings 114 and 134. For example, when the wirings 114 and 134 include a transparent conductive oxide such as ITO, the pad layers 116 and 136 containing metal for preventing connection resistance with the flexible circuit board and for ease of the alignment process. This can be further formed.

For example, the pad layers 116 and 136 include silver (Ag), gold (Au), copper (Cu), aluminum (Al), platinum (Pt), palladium (Pd), chromium (Cr), and titanium (Ti). ), Tungsten (W), niobium (Nb), tantalum (Ta), vanadium (V), iron (Fe), manganese (Mn), cobalt (Co), nickel (Ni), zinc (Zn), or their Alloys.

As illustrated in FIG. 5, the first wiring 114 may extend in a state covered by the insulating layer 120, and may be exposed out of the insulating layer 120 by the first opening 152 in the pad region. . As described above, in the first opening 152, the first pad layer 116 may be formed on the first wiring 114.

As shown in FIG. 6, the second wiring 134 extends on the insulating layer 120 by being covered by the passivation layer 140, and the passivation layer 140 is formed by the second opening 154 in the pad region. ) May be exposed outside.

In the second opening 154, the second wiring 134 may extend continuously along the sidewall of the insulating layer 120 and the top surface of the base layer 100. As described above, the second pad layer 136 may be formed on the second wiring 134 in the second opening 154.

As described above, the first wirings 114 and the second wirings 134 pass through the openings 152 and 154 that pass through the passivation layer 140 and the insulating layer 120 together within the pad region. It may be located at the same layer or the same level (for example, the upper surface of the base layer 100). Thus, the external circuit bonding process through the flexible circuit board can be performed in a substantially single process.

Embodiments of the present invention provide an image display device including the above-described touch sensor. For example, the touch sensor may be inserted between the window and the display panel of the image display device.

The display panel may include, for example, a liquid crystal display (LCD) panel or an organic electroluminescent display (OLED) panel. For example, the display panel may include a pixel circuit including a thin film transistor (TFT) and a pixel portion connected to the pixel circuit. The pixel circuit may include electrodes such as data lines, scan lines, driving lines, and the like, which are regularly arranged according to the arrangement of the pixel units. The pixel unit may include a liquid crystal device or an OLED device, and may include a pixel electrode and an opposite electrode.

The touch sensor according to the exemplary embodiments described above includes sensing electrodes distributed in a plurality of levels, and even when the image display device is downsized, the area of the non-active area by the wirings is reduced so that a high resolution and high sensitivity are provided. The sensing function of can be implemented.

100: substrate layer 110: first conductive pattern
112: first sensing electrode 114: first wiring
116: first pad layer 120: insulating layer
130: second conductive pattern 132: second sensing electrode
134: second wiring 136: second pad layer
140: passivation layer 152: first opening
154: second opening

Claims (15)

Base layer;
A first conductive pattern formed on the base layer and including first wirings and first wirings branching from the first sensing electrodes, respectively; And
A second conductive pattern spaced apart from the first conductive pattern and disposed on the first conductive pattern, the second conductive pattern including second sensing electrodes and second wirings branching from and extending from the second sensing electrodes, respectively; Touch sensor.
The touch sensor of claim 1, wherein the second sensing electrodes overlap with the first wires in a thickness direction of the touch sensor.
The method of claim 1, wherein the first sensing electrodes are arranged in a first direction parallel to the top surface of the base layer to form a first sensing electrode row, and the plurality of first sensing electrode rows are formed on the top surface of the base layer. Are arranged along a second direction parallel to and intersecting the first direction,
And the second sensing electrodes are arranged along the first direction to form a second sensing electrode row, and the plurality of second sensing electrode rows are arranged along the second direction.
The touch sensor of claim 3, wherein the first sensing electrode columns and the second sensing electrode columns are alternately arranged alternately on the same plane.
The touch sensor of claim 4, wherein the second sensing electrode column overlaps the first wires connected to the adjacent first sensing electrode column on the same plane.
The touch sensor of claim 4, wherein the second wires connected to the second sensing electrode row overlap the first sensing electrode row on the same plane.
The method of claim 1, further comprising an insulating layer covering the first conductive pattern on the substrate layer,
And the second conductive pattern is disposed on the insulating layer.
The touch sensor of claim 7, further comprising a passivation layer on the insulating layer to cover the second conductive pattern.
The touch sensor of claim 8, wherein the insulating layer and the passivation layer include a first opening exposing end portions of the first wires and second openings exposing end portions of the second wires.
The touch sensor of claim 9, further comprising a first pad layer formed on the end portions of the first wires, and a second pad layer formed on the end portions of the second wires.
The touch sensor of claim 10, wherein the first wires and the second wires include a transparent conductive oxide, and the first pad layer and the second pad layer include metal.
The touch sensor of claim 9, wherein the end portions of the first wires and the second wires are on the same layer or the same level.
The touch sensor of claim 1, wherein the self-capacitive touch sensor is used.
The touch sensor of claim 13, wherein the first sensing electrodes and the second sensing electrodes each have an independent island pattern.
The image display apparatus containing the touch sensor of any one of Claims 1-14.

Images