TW201342169A - Capacitive touch panel and method of manufacturing the same - Google Patents

Abstract

The present disclosure provides a capacitive touch panel and a method of manufacturing the same. In an embodiment, a capacitive touch panel includes a substrate, a plurality of conductive bridges, a conductive layer, and a plurality of insulators. The conductive bridges are disposed over the substrate and spaced apart along a first direction. The conductive layer includes a first sensing array and a second sensing array, wherein the first sensing array and the second sensing array collectively forms an interleaving pattern and are isolated from each other. The first sensing array includes a plurality of first sensing pads disposed over the substrate and spaced apart along the first direction. The second sensing array includes a plurality of second sensing pads and a plurality of connecting portions continuously disposed over the substrate along a second direction. The insulators are disposed between the conductive bridges and the connecting portions for electrical isolation. The first sensing pads at least cover a portion of the top surface of the conductive bridges and are electrically connected to each other by the conductive bridges.

Description

Capacitive touch device and manufacturing method

The present invention relates to a touch device and a method of fabricating the same, and more particularly to a capacitive touch device and a method of fabricating the same.

The touch device can be classified into a resistive type, a capacitive type, an ultrasonic type, an optical (infrared) type, an electromagnetic type, and the like according to the sensing principle. The capacitive touch device obtains the coordinate of the touch position by the change of the capacitance generated by the contact between the transparent electrode and the human body or the conductive object, and the capacitive touch technology can be combined with the panel technology to manufacture the capacitive touch panel. By applying a voltage around the sensing region to form a uniform electric field, when the human body or the conductive object contacts the capacitive touch device (capacitive touch panel), a coupling capacitor is formed, and the current under the touch position is sucked to cause an electric field change. After the IC calculation and system interpretation, the coordinate position can be obtained.
Capacitive touch devices are suitable for consumer electronics because they can be reacted, scratched, and light transmissive compared to resistive touch devices. A conventional capacitive touch device includes a substrate, a plurality of conductive layers, and an insulating layer. The plurality of conductive layers are two sets of sensing arrays that intersect vertically and horizontally along a first direction and a second direction, and are in two sets of sensing arrays. An insulating layer is interposed to form a bridge structure. However, in the conventional capacitive touch device, two sets of sensing arrays are separately formed, that is, after forming the underlying sensing array, an insulating layer is formed first, and then an upper sensing array is formed, which is cumbersome and increases the production cost. Moreover, the conductive layer generally uses a transparent conductive material with a relatively high resistance, such as ITO (Indium Tin Oxide), which reduces the sensitivity of the capacitive touch device and reduces the performance of the product. Another conventional capacitive touch device is to form a sensing pad in at least one of the first direction or the second direction, and then connect the adjacent sensing pads across the insulating layer using a metal conductive bridge. However, the metal conductive bridge is located at the top of the structure and is susceptible to oxidation, which reduces product reliability. Therefore, although there is a generally applicable capacitive touch device and a manufacturing method, it is still an objective of the technical personnel to seek a simple and effective production process.
In view of the above problems, the present invention provides a capacitive touch device and a manufacturing method thereof, which overcome the problems of the complicated process of the conventional capacitive touch device, the high resistance of the conductive layer, and the oxidation of the metal conductive bridge at the top of the structure.

An embodiment of the present invention provides a capacitive touch device including: a substrate; a plurality of conductive bridges disposed on the substrate in a first direction; a conductive layer disposed on the substrate, the conductive layer including a first An array of sensing regions and a second array of sensing regions are staggered and isolated from each other, wherein the first sensing region array includes a plurality of first sensing pads spaced along the first direction, the second sensing region array The plurality of second sensing pads and the plurality of connecting portions are continuously disposed along a second direction, wherein the first direction is different from the second direction; and the plurality of insulators are sandwiched between the conductive bridges and the connecting portions, Electrically insulating the conductive bridges and the connecting portions, wherein the first sensing pads are electrically connected by the conductive bridges, and the first sensing pads extend at least to cover the conductive bridges The upper surface.
Another embodiment of the present invention provides a method of fabricating a capacitive touch device, including: providing a substrate; forming a plurality of conductive bridges along a first direction on the substrate; forming a plurality of insulators over the conductive bridges; and forming a conductive layer on the substrate, the conductive layer comprising a first sensing region array and a second sensing region array staggered and isolated from each other, wherein the first sensing region array comprises an interval along the first direction a plurality of first sensing pads, the second sensing region comprising a plurality of second sensing pads and a plurality of connecting portions continuously disposed along a second direction, the first direction being different from the second direction, wherein the conductive bridges Before the conductive layer is formed, the first sensing pads are electrically connected.
The above and other objects, features and advantages of the present invention will become more <RTIgt;

The present invention is provided to illustrate the technical features of the present invention. The contents of the embodiments and the drawings are for illustrative purposes only and are not intended to limit the scope of the present invention. Non-essential elements may be omitted from the drawings, and different features may not be drawn to scale and are for illustrative purposes only. The present disclosure may have overlapping element symbols in different embodiments and does not represent an association between different embodiments or drawings. In addition, an element formed "above", "above", "below" or "below" another element may include an embodiment in which two elements are in direct contact, or may include other additional elements interposed between the two elements. An embodiment. The various components may be displayed at any different scale to make the illustration clear and concise.
Referring to FIG. 1 and FIG. 2A-2B, FIG. 1 is a plan view of an embodiment of the present invention, FIG. 2A is a cross-sectional view taken along line A-A' in FIG. 1, and FIG. 2B is a perspective view. A bridging structure for explaining a capacitive touch device according to an embodiment of the present invention. The capacitive touch device 100 includes a substrate 110, a conductive bridge 120, an insulator 130, and a conductive layer 140. The conductive layer 140 includes a first sensing region array 142 and a second sensing region array 144 that are staggered and isolated from each other.
The plurality of conductive bridges 120 are disposed on the substrate 110 at a predetermined interval X. In an embodiment, the plurality of conductive bridges 120 may be sequentially arranged at a specific pitch on the substrate 110 to form a two-dimensional array. This particular spacing may be an identical or close distance, but is not limited thereto. In an embodiment, the conductive bridge 120 may comprise a low resistance metal such as molybdenum (Mo), aluminum (Al), niobium (Nb), niobium (Nd), silver (Ag), copper (Cu), nickel (Ni). ), gold (Au), iron (Fe), tin (Sn), or an alloy of the foregoing metals. In another embodiment, the conductive bridge 120 may include a transparent metal oxide having a relatively high resistance, such as Indium Tin Oxide (ITO), Aluminium Oxide (AZO), and Zinc Oxide (ZnO). ), Antimony Tin Oxide (ATO), tin dioxide (SnO ₂ ), indium oxide (In ₂ O ₃ ), or a combination thereof. In yet another embodiment, the conductive bridge 120 comprises an organic conductive material, such as a conductive polymer composite, an organic conductive polymer, or a combination of the foregoing. The above conductive polymer composite material comprises polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), poly on a conductive carbon tube, carbon fiber, activated carbon, or metal as a conductive additive. Carbonate (PC), ABS resin, polyamide, liquid crystal polymer (LCP), polyetheretherketone (PEEK), or a combination of the foregoing. The above organic conductive polymer includes a polythiophene-based conductive polymer (for example, PEDOT), a polyacetylene (PA)-based conductive polymer, a polyaniline (PAN)-based conductive polymer, or a polypyrrole (PPY)-based conductive polymer. A polyaromatic hydrocarbon (PArV)-based conductive polymer, or a combination thereof. The conductive bridge 120 may be stacked in a single layer or a plurality of layers. In an embodiment, the conductive bridge 120 is elongated. The conductive bridge 120 can be electrically connected to electrically connect the first sensing pads 142a of the first sensing region array 142 in the first direction X.
The conductive layer 140 includes a first sensing region array 142 and a second sensing region array 144. The first sensing area array 142 includes a plurality of first sensing pads 142a disposed along the first direction X. The plurality of first sensing pads 142a are disposed on the substrate 110 at intervals of the conductive bridge 120, and each first sense The pad 142a extends over a portion of the upper surface of each of the conductive bridges 120. This first sensing pad 142a can be any suitable shape. In an embodiment, the first sensing pad 142a is diamond shaped. In other embodiments, the first sensing pad 142a may have a polygonal or elliptical shape. The second sensing region includes a plurality of second sensing pads 144a and a plurality of connecting portions 144b disposed along a second direction Y, the second direction Y being different from the first direction X. Each of the second sensing pads 144a is disposed on the substrate 110 at a specific pitch, and the adjacent second sensing pads 144a are physically and electrically connected in the second direction Y by the connecting portion 144b. This particular spacing may be an identical or close distance, but is not limited thereto. The second sensing pad 144a can be any suitable shape. In an embodiment, the second sensing pad 144a is diamond shaped. In other embodiments, the second sensing pad 144a may have a polygonal or elliptical shape. The size of the second sensing pad 144a and the first sensing pad 142a may be the same or similar. The first sensing region array 142 and the second sensing region array 144 are staggered and have an interlaced angle, which is an angle between the first direction X and the second direction Y. The stagger angle can be 90 degrees but is not limited thereto, and in one embodiment, the stagger angle is 90 degrees.
Conductive layer 140 can include a transparent or opaque conductive material. In one embodiment, the conductive layer 140 includes indium tin oxide (ITO), aluminum zinc oxide (AZO), zinc oxide (ZnO), antimony tin oxide (ATO), tin dioxide (SnO ₂ ), indium oxide (In ₂ O ₃ ), or a combination of the foregoing. In another embodiment, conductive layer 140 comprises an organic conductive material, such as a conductive polymer composite, an organic conductive polymer, or a combination of the foregoing. The above conductive polymer composite material comprises polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), poly on a conductive carbon tube, carbon fiber, activated carbon, or metal as a conductive additive. Carbonate (PC), ABS resin, polyamide, liquid crystal polymer (LCP), polyetheretherketone (PEEK), or a combination of the foregoing. The above organic conductive polymer includes a polythiophene-based conductive polymer (for example, PEDOT), a polyacetylene (PA)-based conductive polymer, a polyaniline (PAN)-based conductive polymer, or a polypyrrole (PPY)-based conductive polymer. A polyaromatic hydrocarbon (PArV)-based conductive polymer, or a combination thereof. In yet another embodiment, the conductive layer 140 comprises copper, aluminum, silver, gold, or a combination of the foregoing.
The insulator 130 is interposed between each of the conductive bridges 120 and the second sensing region arrays 144 disposed along the first direction X, covering the upper surface of the conductive bridge 120 and its adjacent substrate 110, in physical The conductive bridge 120 and the connecting portion 144b are electrically and electrically isolated to prevent the first sensing region array 142 from being short-circuited with the second sensing region array 144. The connecting portion 144b of the second sensing region array 144 spans over the insulator 130 to connect the adjacent second sensing pads 144a. In an embodiment, the insulators 130 are individually separated and may be the same or similar in size. The insulator 130 can be any suitable shape. In one embodiment, the insulator 130 is rectangular. In other embodiments, the insulator 130 can have other shapes, such as an elliptical shape. Insulator 130 may comprise a transparent or opaque insulating material. In one embodiment, insulator 130 may be yttria or other suitable insulating material such as tantalum nitride, niobium oxynitride, or combinations of the foregoing. In another embodiment, the insulator may comprise an organic insulating material such as acrylic acid resin, polyamidamine (PI), polymethyl methacrylate (PMMA), polyethylene tetrahydro ketone (PVP). Polystyrene (PS), polyvinylidene fluoride (PVDF), or a combination of the foregoing.
The substrate 110 can provide mechanical support for the capacitive touch device. The substrate 110 may comprise an insulating sheet of any material, such as glass, plastic, ceramic, rubber, or a combination of the foregoing.
As described above, the conductive bridge 120, the insulator 130, and the connecting portion 144b together constitute a bridging structure 150 on the substrate 110, and the conductive bridge 120 is located at the bottom of the bridging structure 150. The bridge structure 150 can form a capacitor. When no conductive object is in contact with the capacitive touch device, the total capacitance of each of the first sensing region array 142 and the second sensing region array 144 is a fixed value. When the human body or the conductive object is in contact with the capacitive touch device, a coupling capacitor is formed, and the current under the touch position is sucked to cause an electric field change. After IC calculation and system interpretation, the coordinate position of the contact point can be obtained.
Compared with the conventional capacitive touch device, the conductive bridge is exposed on the top of the bridge structure (for example, the publication number TW M364912), and the capacitive touch device provided by the present invention provides the conductive bridge 120 at the bottom of the bridge structure 150. The conductive bridge 120 protects the conductive bridge 120 from subsequent processes (such as an etching process) and deteriorates the electrical properties of the device. In an embodiment, when the material of the conductive bridge 120 is metal (for example, molybdenum, aluminum, tantalum, niobium, silver, copper, nickel, gold, iron, tin, or an alloy of the foregoing metals), the structure above the conductive bridge 120 is protected. In addition to function, it can also prevent metal oxidation and improve product reliability. In contrast, the manner in which the metal conductive bridge is placed on top of the bridge structure in the prior art, such as the publication number TW M364912, may cause oxidation or damage to the conductive bridge.
In another embodiment of the present invention, the first sensing pad 142a may extend over the upper surface of the insulator 130 as shown in FIGS. 3A-3B. FIG. 3A is a top view for explaining a capacitive touch device 200 according to another embodiment of the present invention. FIG. 3B is a cross-sectional view taken along line BB' of FIG. 3A for illustrating the bridging structure 250 of the capacitive touch device 200. In this embodiment, in order to avoid the disconnection of the first sensing pad 242a due to over-etching to the conductive bridge 120 when the sensing array is patterned, the first sensing pad 242a is further extended to cover the portion of the insulator 130. The upper surface is divided to ensure an electrical connection between the first sensing pad 242a and the conductive bridge 120.
Referring to FIGS. 4A-4D, a method of fabricating a capacitive touch device according to an embodiment of the present invention will be described below. Referring first to FIG. 4A, a substrate 110 is provided. The substrate 110 can provide mechanical support for a capacitive touch device. The substrate 110 may comprise an insulating sheet of any material, such as glass, plastic, ceramic, rubber, or a combination of the foregoing.
Referring to FIG. 4B and FIG. 1, a plurality of conductive bridges 120 along a first direction X are formed on the substrate 110. The conductive bridge 120 can be formed using physical or chemical deposition, printing, sputtering, spraying, or other suitable methods. In one embodiment, the conductive bridge 120 can be formed using sputtering and lithography and etching processes, and related processes. It is well known to those skilled in the art and will not be described here. The conductive bridge 120 may be stacked in a single layer or a plurality of layers. In an embodiment, the conductive bridge 120 is elongated. In the conventional process, the conductive bridge is usually formed after the conductive layer and the insulating layer, so that the conductive bridge of the conventional capacitive touch device is exposed at the top of the bridge structure. The invention provides a better protection effect by forming a conductive bridge and then forming other film layers in the bridge structure, so that the conductive bridge is located at the bottom of the bridge structure to provide a better protection effect. When the conductive bridge 120 uses metal, the steps and steps of forming the conductive bridge 120 are performed. The wire step can be completed in the same process. Since the outer circuit and the conductive bridge can use the same material, the desired pattern of the conductive layer can be added to the mask design and completed in the same step, which simplifies the process and reduces the production cost.
Referring to FIG. 4C and FIG. 1, a plurality of insulators 130 are formed to cover the respective conductive bridges 120. The insulator 130 can be any suitable shape. In one embodiment, the insulator 130 is rectangular. In other embodiments, the insulator 130 can have other shapes, such as an elliptical shape. Insulator 130 can be formed using physical or chemical deposition, printing, sputtering, spraying, or other suitable method. The insulator 130 covers the upper surface of the conductive bridge 120 and its adjacent substrate 110 to provide physical and electrical isolation of the conductive bridge 120.
Referring to FIG. 4D and FIG. 1, a conductive layer 140 is formed on the substrate 110. Conductive layer 140 can be formed using physical or chemical deposition, printing, sputtering, spraying, or other suitable method. In one embodiment, the conductive layer 140 is formed by sputtering, and the first sensing region array 142 and the second sensing region array 144 are formed by a lithography and etching process. The first sensing region array 142 and the second The sense region array 144 is formed in the same process step. The first sensing region array 142 and the second sensing region array 144 are staggered and isolated from each other, and the first sensing region array 142 and the second sensing region array 144 have an interlaced angle. The angle between a direction X and a second direction Y. The stagger angle can be 90 degrees but is not limited thereto, and in one embodiment, the stagger angle is 90 degrees. In the present invention, since the first bridge 142a is formed by forming the conductive bridge 120 first, a part of the upper surface of the conductive bridge 120 is covered by the first sensing pad 142a. In the conventional process, since the conductive layer is formed before the conductive bridge, the conductive layer does not cover the conductive bridge. In addition, since the conductive bridge and the conductive layer of the present invention are separately formed, the conductive bridge and the conductive layer can be made of different materials. For example, the conductive bridge can be made of a metal material under the condition that the conductive layer uses a transparent conductive material, so that the capacitive touch device is used. Improve device sensitivity while permeable. Moreover, since the first sensing area array 142 and the second sensing area array 144 are formed in the same process step, the number of masks can be saved, and steps, such as exposure, development, etching, and the like required for the process are reduced.
In another embodiment of the present invention, as shown in FIGS. 3A-3B, the first sensing pad 142a may be further extended to cover the upper surface of the insulator 130 to avoid the first sensing of the first sensing array 242. The pad 242a has an over-etching condition when patterning the sensing array and cannot be connected to the open-circuit problem of the conductive bridge 120, ensuring an electrical connection between the first sensing pad 242 and the conductive bridge 120.
While the invention has been described above in terms of several preferred embodiments, it is not intended to limit the scope of the present invention, and any one of ordinary skill in the art can make any changes without departing from the spirit and scope of the invention. And the scope of the present invention is defined by the scope of the appended claims.

100, 200. . . Capacitive touch device

110. . . Substrate

120. . . Conductive bridge

130. . . Insulator

140. . . Conductive layer

142, 242. . . First sensing area array

142a, 242a. . . First sensing pad

144. . . Second sensing area array

144a. . . Second sensing pad

144b. . . Connection

150, 250. . . Bridging structure

X. . . First direction

Y. . . Second direction

1 is a top plan view illustrating a capacitive touch device according to an embodiment of the invention.
2A is a cross-sectional view taken along line A-A' of FIG. 1 for explaining the bridging structure of the capacitive touch device according to an embodiment of the present invention.
FIG. 2B is a perspective view of the capacitive touch device according to an embodiment of the invention, illustrating a perspective view taken along line A-A' of FIG. 1.
FIG. 3A is a top view for explaining a capacitive touch device according to another embodiment of the present invention.
FIG. 3B is a cross-sectional view taken along line BB' of FIG. 3A for explaining a capacitive touch device according to another embodiment of the present invention.
4A-4D are a series of cross-sectional views illustrating several fabrication steps of a capacitive touch device in accordance with an embodiment of the present invention.

110. . . Substrate

120. . . Conductive bridge

130. . . Insulator

142a. . . First sensing pad

144b. . . Connection

150. . . Bridging structure

Claims (13)

A capacitive touch device includes:
a substrate;
a plurality of conductive bridges disposed on the substrate at a distance along a first direction;
a conductive layer disposed on the substrate, the conductive layer including a first sensing region array and a second sensing region array staggered and isolated from each other, wherein the first sensing region array includes spacing along the first direction a plurality of first sensing pads, the second sensing region array includes a plurality of second sensing pads and a plurality of connecting portions continuously disposed along a second direction, the first direction being different from the second direction; and the plurality of insulators Between the conductive bridges and the connecting portions, electrically insulating the conductive bridges and the connecting portions,
The first sensing pads are electrically connected by the conductive bridges, and the first sensing pads extend at least to cover a portion of the upper surfaces of the conductive bridges. The capacitive touch device of claim 1, wherein the conductive bridge comprises molybdenum, aluminum, tantalum, niobium, silver, copper, nickel, gold, iron, tin, or an alloy of the foregoing metals. The capacitive touch device of claim 1, wherein the conductive bridge comprises indium tin oxide, aluminum zinc oxide, zinc oxide, antimony tin oxide, tin dioxide, indium oxide, or a combination thereof. The capacitive touch device of claim 1, wherein the conductive bridge comprises a conductive polymer composite material, an organic conductive polymer, or a combination thereof, wherein the conductive polymer composite material comprises a nanometer conductive carbon. Tube, carbon fiber, activated carbon, or metal as conductive additive for polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polycarbonate (PC), ABS resin, polyamine Polyamide, liquid crystal polymer (LCP), polyetheretherketone (PEEK), or a combination of the foregoing, wherein the organic conductive polymer comprises a polythiophene-based conductive polymer (eg, PEDOT), polyacetylene (PA) A conductive polymer, a polyaniline (PAN)-based conductive polymer, or a polypyrrole (PPY)-based conductive polymer, a polyaromatic hydrocarbon (PArV)-based conductive polymer, or a combination thereof. The capacitive touch device of claim 1, wherein the conductive layer comprises indium tin oxide, aluminum zinc oxide, zinc oxide, antimony tin oxide, tin dioxide, indium oxide, or a combination thereof. The capacitive touch device of claim 1, wherein the conductive layer comprises a conductive polymer composite material, an organic conductive polymer, or a combination thereof, wherein the conductive polymer composite material comprises nano conductive carbon. Tube, carbon fiber, activated carbon, or metal as conductive additive for polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polycarbonate (PC), ABS resin, polyamine Polyamide, liquid crystal polymer (LCP), polyetheretherketone (PEEK), or a combination of the foregoing, wherein the organic conductive polymer comprises a polythiophene-based conductive polymer (eg, PEDOT), polyacetylene (PA) A conductive polymer, a polyaniline (PAN)-based conductive polymer, or a polypyrrole (PPY)-based conductive polymer, a polyaromatic hydrocarbon (PArV)-based conductive polymer, or a combination thereof. The capacitive touch device of claim 1, wherein the conductive layer comprises copper, aluminum, silver, gold, or a combination thereof. The capacitive touch device of claim 1, wherein the insulators comprise ruthenium oxide, tantalum nitride, ruthenium oxynitride, or a combination thereof. The capacitive touch device of claim 1, wherein the insulator comprises an acrylic acid resin, a polyacrylamide (PI), a polymethyl methacrylate (PMMA), a polyethylene Hydrolactone (PVP), polystyrene (PS), polyvinylidene fluoride (PVDF), or a combination of the foregoing. The capacitive touch device of claim 1, wherein the substrate comprises glass, plastic, ceramic, rubber, or a combination thereof. The capacitive touch device of claim 1, wherein the first sensing pads extend over the upper surface of the insulators. A method of fabricating a capacitive touch device according to any one of claims 1 to 11, comprising:
Providing a substrate;
Forming a plurality of conductive bridges along a first direction on the substrate;
Forming a plurality of insulators over the conductive bridges; and forming a conductive layer on the substrate, the conductive layers comprising a first sensing region array and a second sensing region array staggered and isolated from each other, wherein the first The sensing area array includes a plurality of first sensing pads spaced along the first direction, the second sensing area includes a plurality of second sensing pads and a plurality of connecting portions continuously disposed along a second direction, the first direction Different from the second direction,
The conductive bridges are formed before the conductive layer to electrically connect the first sensing pads. The method for fabricating a capacitive touch device according to claim 12, wherein the first sensing region array and the second sensing region array are formed in the same process step.