Stacked structure and touch sensor

Abstract

The present invention discloses a stacked structure, comprising: a substrate; a nanosilver wire layer disposed on the substrate; and a metal layer disposed on the nanosilver wire layer, wherein the nanosilver wire layer comprises: a plurality of nanosilver wires; and a protective coating covering the plurality of nanosilver wires, wherein the thickness of the nanosilver wire layer is between 40 and 120 nm. A touch sensor comprising the stacked structure.

Description

Technical Field

[0001] The present invention relates to a stacked structure, in particular to a stacked structure comprising a nano silver wire layer. The present invention also relates to a touch sensor, in particular to a touch sensor comprising the stacked structure. Background Art

[0002] The stacked structure including nano silver wires and metal layers can be applied to touch sensors. Conventionally, a trace area (TA) including metal wires made of silver is set around the stacked structure through silver paste screen printing and laser processing, and a visible area (VA) not including metal wires is set in the center of the stacked structure, so that the stacked structure can be applied to touch sensors.

[0003] Figure 1 Schematic diagram of the wiring area in the touch sensor formed by the traditional stacked structure after silver paste screen printing and laser processing. Figure 1 As shown, the wiring area 4 includes a substrate 1; a nanosilver wire layer 2, which is disposed on the substrate 1; and a metal layer 3, which is disposed on the nanosilver wire layer 2, and the metal layer 3 forms a plurality of metal wires 5. Limited by the size limit of the laser spot in the laser process, the line width 6 / line spacing 7 of the plurality of metal wires 5 included in the wiring area 4 can only reach a minimum of 30 / 30 μm, which cannot be applied to small-sized touch sensors that require narrow borders. Summary of the invention

[0004] In order to improve the problem of excessive line width and line spacing in the routing area of ​​the stacked structure in the prior art after the traditional silver paste screen printing and laser process, the present invention provides a novel stacked structure and a touch sensor.

[0005] To achieve the above and other purposes, the present invention provides a stacked structure, comprising:

[0006] Base material;

[0007] a nano silver wire layer disposed on the substrate; and

[0008] A metal layer is disposed on the nano silver wire layer,

[0009] Wherein, the nano silver wire layer comprises:

[0010] a plurality of silver nanowires; and

[0011] a protective coating covering the plurality of silver nanowires,

[0012] The thickness of the nano silver wire layer is between 40 nm and 120 nm.

[0013] In the above stacked structure, the protective coating is made of a material selected from the group consisting of acrylate resins, such as epoxy acrylates, urethane acrylates, polyester acrylates and polyether acrylates.

[0014] The above stacked structure may further include:

[0015] A second nanosilver wire layer is disposed under the substrate; and

[0016] A second metal layer is disposed below the second nanosilver wire layer,

[0017] Wherein, the second nano silver wire layer comprises:

[0018] a plurality of silver nanowires; and

[0019] a second protective coating covering the plurality of nano silver wires,

[0020] Wherein, the thickness of the second nano silver wire layer is between 40 nm and 120 nm by weight.

[0021] In the above stacked structure, the thickness of the metal layer is between 150 and 300 nm.

[0022] In the above stacked structure, the thickness of the substrate is between 10 and 150 μm.

[0023] To achieve the above and other purposes, the present invention also provides a touch sensor, comprising:

[0024] The stacked structure mentioned above.

[0025] In the above touch sensor, the silver nanowire layer and the metal layer in the stacked structure included in the touch sensor can be patterned.

[0026] In the above touch sensor, the nano silver wire layer, the second nano silver wire layer, the metal layer and the second metal layer in the stacked structure included in the touch sensor can be patterned.

[0027] The stacked structure of the present invention can be patterned by a photolithography process to form a wiring area with narrower line width and line spacing, thereby enabling a touch sensor using the stacked structure to achieve a narrow frame design. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1This is a schematic diagram of the routing area of ​​a traditional stacked structure after silver paste screen printing and laser processing.

[0029] Figure 2 It is a schematic diagram of the stacked structure of Example 1 of the present invention.

[0030] Figure 3 It is a schematic diagram of the stacked structure of Example 2 of the present invention.

[0031] Figure 4 FIG. 4 is a schematic diagram of a touch sensor and its manufacturing process according to Embodiment 3 of the present invention.

[0032] Figure 5 FIG. 4 is a schematic diagram of a wiring area of ​​a touch sensor according to a third embodiment of the present invention.

[0033] Description of reference numerals:

[0034] 1. Substrate

[0035] 2 Nanosilver wire layer

[0036] 3 Metal Layer

[0037] 4. Routing area

[0038] 5 Metal wire

[0039] 6 Line Width

[0040] 7 Line spacing

[0041] 10 Stacked structure

[0042] 11. Substrate

[0043] 12 nanometer silver wire layer

[0044] 13 Metal Layer

[0045] 20 Stacked Structure

[0046] 22 Second nanosilver wire layer

[0047] 23 Second Metal Layer

[0048] 30 Touch Sensor

[0049] 31 Photoresist

[0050] 32 Second photoresist

[0051] 33 Viewing area

[0052] 34 Routing area

[0053] 35 Metal wire

[0054] 36 Line Width

[0055] 37 Line spacing DETAILED DESCRIPTION

[0056] The following is an explanation of the implementation of the present invention by means of specific embodiments. Those skilled in the art can understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied by means of other different specific embodiments, and the details in this specification can also be modified and changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0057] As used in the specification and the appended claims, the singular forms "a," "an," and "the" include plural references unless the context dictates otherwise.

[0058] As used in the specification and appended claims, the term "or" includes the meaning of "and / or" unless the context dictates otherwise.

[0059] The “line width” described herein refers to the width of a metal conductive line.

[0060] The “line distance” described herein refers to the shortest distance between an edge of a metal conductive line and an edge of another adjacent metal conductive line.

[0061] Example 1

[0062] Figure 2 FIG. 1 is a schematic diagram of a stacked structure 10 according to Embodiment 1 of the present invention. Figure 2 As shown, the stacked structure 10 of Example 1 includes: a substrate 11; a nanosilver wire layer 12, which is disposed on the substrate 11; and a metal layer 13, which is disposed on the nanosilver wire layer 12, wherein the nanosilver wire layer 12 includes: a plurality of nanosilver wires; and a protective coating covering the plurality of nanosilver wires, wherein the thickness of the nanosilver wire layer 12 is between 40 and 120 nm.

[0063] In the stacked structure of Example 1, the materials suitable for the substrate include but are not limited to transparent plastics such as polyethylene terephthalate (PET), cyclic olefin copolymer (COP), and colorless polyimide (CPI). In addition, the thickness of the substrate can be between 10 and 150 μm.

[0064] In the stacked structure of Example 1, the material of the protective coating can be selected from a material selected from the group consisting of acrylate resins, such as epoxy acrylates, urethane acrylates, polyester acrylates and polyether acrylates, but the present invention is not limited thereto.

[0065] In the stacked structure of Example 1, the thickness of the nanosilver wire layer is between 40 and 120 nm. When the thickness of the nanosilver wire layer is less than 40 nm, the overly thin protective coating in the nanosilver wire layer will not be sufficient to protect the nanosilver wire from being damaged by the etching solution during the yellow light etching process, thereby affecting its conductivity, which is not conducive to the application of the stacked structure in the touch sensor. In addition, when a metal layer is set on the nanosilver wire layer by a metal plating process, the overly thin protective coating will not be sufficient to protect the nanosilver wire from being damaged by the metal plating, which is not conducive to the application of the stacked structure in the touch sensor. Relatively speaking, when the thickness of the nanosilver wire layer is greater than 120 nm, the overly thick protective coating in the nanosilver wire layer will make the contact impedance between the nanosilver wire layer and the metal layer above it too large, thereby affecting its conductivity, which is not conducive to the application of the stacked structure in the touch sensor.

[0066] As described above, the stacked structure of the present invention utilizes the technical feature that the thickness of the nano silver wire layer is between 40 and 120 nm, so that the stacked structure can use a yellow light etching process to pattern the metal layer and the nano silver wire layer, thereby forming a routing area with a narrower line width and line spacing, so that the touch sensor using the stacked structure can achieve a narrow frame design, while also maintaining an ideal contact impedance between the nano silver wire layer and the metal layer above it.

[0067] In the stacked structure of Example 1, materials suitable for the metal layer include but are not limited to: copper, nickel, silver, etc., and related alloy metal materials. In addition, the thickness of the metal layer may be between 150 and 300 nm. When the thickness of the metal layer is less than 150 nm, the too thin metal layer will make it unable to obtain the required conductivity, which is not conducive to the application of the stacked structure in the touch sensor. Relatively speaking, when the thickness of the metal layer is greater than 300 nm, the too thick metal layer will cause the bendability of the stacked structure to be poor, which is not conducive to the application of the stacked structure in the touch sensor.

[0068] The stacked structure of Example 1 can be used with a corresponding high selectivity etching solution or a one-time etching etching solution in the yellow light etching process to complete the manufacturing of the touch sensor.

[0069] Example 2

[0070] Figure 3 FIG. 2 is a schematic diagram of a stacked structure 20 according to Embodiment 2 of the present invention. Figure 3 As shown, the stacked structure of Example 2, like the stacked structure of Example 1, comprises: a substrate 11; a nanosilver wire layer 12 disposed on the substrate 11; and a metal layer 13 disposed on the nanosilver wire layer 12, wherein the nanosilver wire layer 12 comprises: a plurality of nanosilver wires; and a protective coating covering the plurality of nanosilver wires, wherein the thickness of the nanosilver wire layer 12 is between 40 and 120 nm.

[0071] Compared to Example 1, the stacked structure 20 of Example 2 further comprises: a second nanosilver wire layer 22 disposed under the substrate 11; and a second metal layer 23 disposed under the second nanosilver wire layer 22, wherein the second nanosilver wire layer 22 comprises: a plurality of nanosilver wires; and a second protective coating covering the plurality of nanosilver wires, wherein the thickness of the second nanosilver wire layer 22 is between 40 and 120 nm.

[0072] In the stacked structure 20 of Example 2, the material of the second protective coating contained in the second silver nanowire layer 22, the thickness of the second silver nanowire layer 22, and the material and thickness of the second metal layer 23 are the same as those of the silver nanowire layer 12 and the metal layer 13 of Example 1, and are not described again.

[0073] The stacked structure of Example 2 can be applied to a touch sensor, wherein the metal layer and the silver nanowire layer can be patterned by a yellow light etching process to form a driving electrode Tx; and the second metal layer and the second silver nanowire layer can be patterned by a yellow light etching process to form a sensing electrode Rx. The arrangement of the metal layer and the second metal layer can prevent interference caused by double-sided exposure in the yellow light etching process.

[0074] Example 3

[0075] Figure 4 FIG. 3 is a schematic diagram of a touch sensor 30 and its manufacturing process according to Embodiment 3 of the present invention. Figure 4 As shown, the touch sensor 30 of the third embodiment includes the stacked structure 10 as described in the first embodiment, and the stacked structure 10 is patterned to meet the requirements of the touch sensor.

[0076] like Figure 4 As shown, the manufacturing process of the touch sensor 30 of the third embodiment includes:

[0077] 1. Take the stacked structure 10 of Example 1;

[0078] 2. Coating photoresist 31;

[0079] 3. Exposure and development to pattern the photoresist 31;

[0080] 4. Etching the metal layer 13 with a high selectivity etching solution;

[0081] 5. Etching with a high selectivity etching solution to etch the nano silver wire layer 12;

[0082] 6. Remove the photoresist 31;

[0083] 7. Apply the second photoresist 32;

[0084] 8. Exposure and development for the second time to pattern the second photoresist 32;

[0085] 9. Etching the metal layer 13 for the second time using a high selectivity metal etching solution; and

[0086] 10. Remove the second photoresist 32 to complete the touch sensor 30 of the third embodiment, wherein the touch sensor 30 comprises a visible area 33 where the silver nanowire layer 12 is not covered by the metal layer 13 , and a wiring area 34 having a plurality of metal wires formed by the metal layer 13 .

[0087] In another embodiment, one etching solution may be used to simultaneously etch the metal layer 13 and the silver nanowire layer 12 , so as to simultaneously complete steps 4 and 5 in the above-mentioned preparation process.

[0088] Figure 5 FIG. 3 is a schematic diagram of a wiring area 34 of a touch sensor 30 according to Embodiment 3 of the present invention. Figure 5 As shown, the wiring area 34 includes a substrate 11; a nano silver wire layer 12, which is disposed on the substrate 11; and a metal layer 13, which is disposed on the nano silver wire layer 12, and the metal layer 13 is patterned to form a plurality of metal wires 35. Through a yellow light etching process, the line width 36 / line spacing 37 of the plurality of metal wires 35 included in the wiring area 34 can reach 10 / 10μm, so that it can be applied to small-sized touch sensors that require narrow borders.

[0089] In summary, the stacked structure and touch sensor of the present invention have at least the following excellent technical effects:

[0090] 1. The stacked structure of the present invention, by virtue of the specific thickness range of the nano silver wire layer, can be used for a yellow light etching process to form a wiring area with a narrower line width and line spacing, thereby enabling a touch sensor using the stacked structure to achieve a narrow frame design, thereby solving the problem of excessively wide line width and line spacing in the wiring area of ​​a conventional touch sensor.

[0091] 2. The stacked structure of the present invention can effectively prevent the damage to the silver nanowires when a metal layer is disposed on the silver nanowire layer by a metal plating process, by virtue of the specific thickness range of the silver nanowire layer.

[0092] 3. The stacked structure of the present invention can effectively prevent the damage to the silver nanowires when etching the metal layer in the yellow light etching process by virtue of the specific thickness range of the silver nanowire layer.

[0093] 4. The stacked structure of the present invention can prevent interference during the double-sided exposure process by providing a metal layer.

[0094] The above embodiments are merely illustrative of the present invention and are not intended to limit the present invention. Any person skilled in the art may modify and alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be as set forth in the following claims.

Claims

1. A stacked structure, characterized in that: Include: Base material; a nano silver wire layer disposed on the substrate; and A metal layer is disposed on the nano silver wire layer, Wherein, the nano silver wire layer comprises: a plurality of silver nanowires; and a protective coating covering the plurality of silver nanowires, The thickness of the nano silver wire layer is between 40 nm and 120 nm.

2. The stacked structure according to claim 1, characterized in that: The protective coating is made of a material selected from the group consisting of epoxy acrylic, urethane acrylic, polyester acrylic and polyether acrylic resins.

3. The stacked structure according to claim 1 or 2, characterized in that: Further including: A second nanosilver wire layer is disposed under the substrate; and A second metal layer is disposed below the second nanosilver wire layer, Wherein, the second nano silver wire layer comprises: a plurality of silver nanowires; and a second protective coating covering the plurality of nano silver wires, Wherein, the thickness of the second nano silver wire layer is between 40 nm and 120 nm by weight.

4. The stacked structure according to claim 1, characterized in that: The thickness of the metal layer is between 150 nm and 300 nm.

5. The stacked structure according to claim 1, characterized in that: The thickness of the substrate is between 10 and 150 μm.

6. A touch sensor, characterized in that: Include: The stacked structure according to any one of claims 1 to 5.

7. The touch sensor according to claim 6, wherein: The touch sensor comprises the stacked structure according to any one of claims 1 to 2, wherein the silver nanowire layer and the metal layer are patterned.

8. The touch sensor according to claim 6, wherein: The touch sensor comprises the stacked structure according to claim 3 , wherein the silver nanowire layer, the second silver nanowire layer, the metal layer and the second metal layer are patterned.

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