TWI538141B - Method for producing conductive circuits and touch screen - Google Patents

Description

Touch screen and conductive line manufacturing method

The present invention relates to a touch screen, and more particularly to a touch screen and a method of fabricating a conductive line.

The touch display device combines touch technology and display technology, and is generally used in electronic products such as mobile phones, media players, navigation systems, digital cameras, and the like as input and display.

Generally, a touch display device is composed of a display device and a touch screen. A display device such as a liquid crystal display. According to the principle of the touch screen, it can be divided into resistive, capacitive, infrared, and surface acoustic wave. Among them, a common capacitive touch screen has a structure in which a plurality of transparent electrodes perpendicularly intersecting each other are disposed on a surface of a glass substrate or a plastic substrate, and the transparent electrodes are connected to the controller through peripheral conductive lines. When the user touches the surface of the touch screen with a finger, the capacitance value between the electrodes at the touch position changes, and the capacitance change signals are transmitted to the controller through the peripheral conductive lines for calculation, thereby confirming The coordinates of the touch position.

The surface of the touch screen can be divided into a "visible area" and a "non-visible area"-frame, the size of which depends on the precision of the conductive line; the more precise the conductive line, the smaller the frame. At present, the conductive circuit manufacturing method of the touch screen is to use screen printing (screen Printing) Direct printing of conductive ink on a substrate to form a conductive trace. The screen printed carrier is a screen, and the conductive line made by the screen printing method has a large line width and line spacing, so the conductive line occupies a large area, so that the area of the non-visible area is large. The area of the viewable area is small. In addition, the use of screen printing to produce conductive lines often results in cracks, breaks, low flatness, or defects in the shape of the wire due to the presence of the wire segments.

In addition, there are also conventional techniques for depositing a metal layer and then etching the metal layer by laser to form a conductive line. However, if a conductive line is formed on a plastic substrate, since the plastic is not resistant to high temperatures, the metal layer must be deposited using a special physical deposition apparatus, which is high in equipment cost and difficult to control the thickness and uniformity of the deposited metal film.

One of the objectives of the present invention is to provide a touch screen and a method for fabricating the same, which can be made by the advantages of printing and laser etching, whereby the conductive line can have high precision and can be Reduce costs and improve quality.

An embodiment of the present invention provides a method of fabricating a conductive line, comprising: printing a conductive layer on a peripheral region of a substrate; and etching the conductive layer to form a plurality of conductive traces.

Further, the conductive layer is formed by screen printing a conductive paste on a peripheral region of the substrate.

Further, the conductive adhesive is one of conductive silver glue, conductive copper glue and conductive graphite glue.

Further, wherein the plurality of conductive lines have a line pitch of 20 μm to 70 μm.

Further, wherein the line spacing of the plurality of conductive lines It is 20 μm to 40 μm.

Further, wherein the plurality of conductive lines have a line width of 20 μm to 70 μm.

Further, wherein the plurality of conductive lines have a line width of 20 μm to 40 μm.

Further, the conductive layer is etched by laser etching to form a complex Several conductive lines.

Further, the laser beam of the laser etching mode is a green laser of 532 nm or 1064 nm wavelength.

Further, wherein the substrate is a transparent organic substrate or a transparent inorganic substrate.

Further, wherein the transparent organic substrate is one of polyethylene terephthalate, polycarbonate, polyethylene, and polymethyl methacrylate.

An embodiment of the present invention provides a touch screen comprising: a touch sensing layer; and a plurality of conductive lines distributed in a peripheral area of the touch sensing layer and connected to the touch sensing layer; The plurality of conductive lines are formed by printing a conductive layer on a peripheral region of a substrate and etching the conductive layer.

Further, the conductive layer is formed by screen printing a conductive paste on a peripheral region of the substrate.

Further, the conductive adhesive is one of conductive silver glue, conductive copper glue and conductive graphite glue.

Further, wherein the plurality of conductive lines have a line pitch of 20 μm to 70 μm.

Further, wherein the line spacing of the plurality of conductive lines It is 20 μm to 40 μm.

Further, wherein the plurality of conductive lines have a line width of 20 μm to 70 μm.

Further, wherein the plurality of conductive lines have a line width of 20 μm to 40 μm.

Further, wherein the substrate is a transparent organic substrate or a transparent inorganic substrate.

Further, wherein the transparent organic substrate is one of polyethylene terephthalate, polycarbonate, polyethylene, and polymethyl methacrylate.

Further, the touch sensing layer is a single layer single axis structure and a single layer One of a two-axis structure and a two-layer two-axis structure.

A method for manufacturing a conductive line and a touch screen provided by an embodiment of the present invention The conductive lines are fabricated by the respective manufacturing advantages of printing and laser etching, whereby the conductive lines can have high precision and can reduce cost and improve quality.

11-12‧‧‧How to make conductive lines

20‧‧‧Substrate

20A‧‧‧Substrate/substrate surface

20B‧‧‧Substrate/substrate surface

22‧‧‧ Conductive layer

24‧‧‧Electrical circuit

26‧‧‧Touch sensing layer

26A‧‧‧First conductive pattern

26B‧‧‧Second conductive pattern

1 is a schematic flow chart of a method for fabricating a conductive line according to a first embodiment of the present invention.

2A is a schematic view of a first process of the fabrication method shown in FIG. 1.

2B is a schematic view showing a second process of the manufacturing method shown in FIG. 1.

FIG. 3 is a schematic structural diagram of a touch screen according to a second embodiment of the present invention.

4 is a schematic structural view of a touch sensing layer of a single-layer single-axis structure of the touch screen shown in FIG.

FIG. 5 is a schematic structural view of a touch sensing layer of a single-layer dual-axis structure of the touch screen shown in FIG.

6A and 6B show the structure of a touch sensing layer of a double-layer biaxial structure of the touch screen shown in FIG. schematic diagram.

The embodiments of the present invention will be described in detail below with reference to the drawings. In addition to the detailed description, the present invention may be widely practiced in other embodiments, and any alternatives, modifications, and equivalent changes of the embodiments are included in the scope of the present invention, and the scope of the following patents shall prevail. . In the description of the specification, numerous specific details are set forth in the description of the invention. In addition, well-known steps or elements are not described in detail to avoid unnecessarily limiting the invention. The same or similar elements in the drawings will be denoted by the same or similar symbols. It is specifically noted that the drawings are for illustrative purposes only and do not represent the actual dimensions or quantities of the components unless otherwise specified.

1, FIG. 2A and FIG. 2B are diagrams showing a method for fabricating a conductive line according to a first embodiment of the present invention, wherein FIG. 1 is a flow chart of the method for fabricating the conductive line, and FIG. 2A and FIG. Schematic diagram of the first process and the second process. Referring to Figures 1, 2A and 2B, a method for fabricating a conductive line according to a first embodiment of the present invention includes:

In step 11, a conductive layer 22 is printed to form a peripheral region of a substrate 20, as shown in FIGS. 1 and 2A. The method of forming the conductive layer 22 may be performed by using a printing method known in the art or by screen printing a conductive paste on the peripheral region of the substrate 20. The conductive paste may be, but not limited to, a conductive silver paste. , conductive copper glue and conductive graphite glue. The substrate 20 is a transparent inorganic substrate, such as a glass substrate; or a transparent organic substrate, such as a plastic substrate, such as polyethylene terephthalate (PET), polycarbonate. (Poly Carbonate, PC), Polyethylene (PE) or Poly Polymethylmethacrylate (PE), etc.

In step 12, the conductive layer 22 is etched to form a plurality of conductive traces 24, as shown in FIG. 2B. The method of etching the conductive layer 22 is preferably a laser etching method, but may be a method such as dry etching or wet etching. The laser etching method selects a laser beam having a wavelength including: the substrate 20 is not damaged, and the absorption rate absorbed by the conductive layer 22 is greater than the absorption rate absorbed by the substrate 20. Specifically, in the embodiment, the substrate 20 can be selected from a PET substrate, and the laser beam is selected from a green laser of 532 nm or 1064 nm wavelength, which has a narrow line width, a small laser heat affected area, and a silver gel to 532 nm and 1064 nm laser. The absorption is strong, while the PET substrate has the advantage of weak absorption of the 532 nm and 1064 nm lasers.

Since the laser etching precision is relatively easy to control, the line spacing of the plurality of conductive lines can reach about 20 μm to 70 μm by using the manufacturing method of the embodiment of the present invention. Further, the line spacing of the plurality of conductive lines can reach about 20 μm to 40 μm. With the fabrication method of the embodiment of the present invention, the line widths of the plurality of conductive lines can reach about 20 μm to 70 μm. Further, the plurality of conductive lines may have a line width of about 20 μm to 40 μm.

For example, the laser wavelength is 532 nm, the power is 10 W, the laser beam adjustment frequency is 100 KHZ, the scribing speed is 250 mm/s, the laser pulse spacing is 0.002 mm, and the laser pulse time is 15 μs. Fine conductive lines with line width/line spacing = 30 ± 10 μm can be etched according to the above parameters. And the height difference between the line pitch and the transparent substrate (for example, PET) can be controlled within 4 μm.

The conductive lines fabricated by the method provided by the embodiments of the present invention can meet various specifications. These specifications include adhesion, hardness, and various reliability tests such as high temperature testing, low temperature testing, high temperature and high humidity testing, hot and cold cycle testing, brine testing, and thermal shock testing. Further, the conductive line was observed with a microscope with a line width/line pitch of 30 ± 10 μm, and the height difference between the line pitch and the transparent substrate (e.g., PET) was controlled to be within 4 μm.

FIG. 3 shows a touch screen 30 according to a second embodiment of the present invention, which includes a touch sensing layer 26 and a plurality of conductive lines 24 . The touch sensing layer 26 is disposed in a central area of the touch screen 30 , and the conductive lines 24 are distributed in the peripheral area of the touch sensing layer 26 and connected to the touch sensing layer 26 . The touch sensing layer 26 is configured to sense a touch position of the user, and generate a touch signal, and the touch signal is transmitted to the controller through the conductive line 24 for calculation to determine a coordinate of the touch position. Wherein, the plurality of conductive lines 24 are printed by forming a conductive layer on a peripheral region of a substrate, and then etching the conductive layer. It should be noted that the plurality of conductive lines may be formed by using the manufacturing method of the conductive lines in the first embodiment, and details are not described herein.

Preferably, the touch screen 30 is a capacitive touch screen, and the touch sensing layer 26 can be a single layer single axis structure, a single layer double axis structure and a double layer double axis structure. One. The structure of the touch sensing layer 26 will be described below in a specific embodiment.

4 shows a touch sensing layer of a touch screen according to a third embodiment of the present invention, which is a single layer single axis structure. As shown in the figure, the touch sensing layer includes a first conductive pattern 26A arranged on the substrate 20 in a first axial direction.

FIG. 5 shows a touch sensing layer of a touch screen according to a fourth embodiment of the present invention, which is a single layer dual axis structure. As shown in the figure, the touch sensing layer includes a plurality of first conductive patterns 26A arranged in a first axial direction and a plurality of second conductive patterns 26B arranged in a second axial direction, a first conductive pattern 26A and a second conductive pattern 26B. They are disposed on the same surface of the substrate 20 so as to intersect each other and insulatively.

6A and 6B show a touch sensing layer of a touch screen according to a fifth embodiment of the present invention, which is a double-layer biaxial structure. As shown in the figure, the touch sensing layer comprises a plurality of first conductive patterns 26A arranged on the surface of the substrate 20A in a first axial direction, and a plurality of second conductive patterns arranged on the surface of the substrate 20B and arranged in a second axial direction. 26B constitutes. And the first conductive pattern The 26A and the second conductive pattern 26B are respectively connected to the conductive lines (not shown) of the peripheral area, and the touch signals are transmitted to the controller for calculation by the conductive lines of the peripheral area, thereby determining the coordinates of the touch position. Note that component symbols 20A and 20B may also represent two opposing surfaces of the same substrate.

It should be noted that, in the foregoing embodiments, the substrate 20 may be a transparent inorganic substrate, such as a glass substrate, or a transparent organic substrate, such as a plastic substrate, such as polyethylene terephthalate. Polyethylene terephthalate (PET), polycarbonate (Poly Carbonate, PC), polyethylene (Polyethylene, PE) or polymethylmethacrylate (PE). The first conductive pattern 26A, the second conductive portion 26B may be made of a transparent conductive material, and the transparent conductive material may be selected from one or a combination of the following groups: indium tin oxide (ITO), antimony tin oxide (ATO), Zinc oxide (ZnO), zinc dioxide (ZnO ₂ ), tin dioxide (SnO ₂ ), indium trioxide (In ₂ O ₃ ).

The method for manufacturing a conductive line and the touch screen provided by the embodiment of the invention form a conductive layer by using a printing method, and then etching the conductive layer by etching to form a plurality of conductive lines respectively connected to the conductive pattern. By using the method of the invention, fine conductive lines can be fabricated on the limited frame area, and the physical deposition method can be used, the manufacturing cost can be reduced, and many steps such as exposure, development, etching, etc. can be reduced, and the production efficiency can be improved.

The above is only the preferred embodiment of the present invention, and is not intended to limit the scope of the claims of the present invention; any other equivalent changes or modifications which are not departing from the spirit of the invention should be included in the application below. Within the scope of the patent.

11‧‧‧Printing forms a conductive layer in the peripheral region of a substrate

12‧‧‧ Etching the conductive layer to form a plurality of conductive lines

Claims (5)

A method for fabricating a conductive line, comprising: providing a substrate, a peripheral region of the substrate having an insulating surface; printing a conductive paste on the insulating surface of the peripheral region by screen printing; and etching the conductive The glue forms a plurality of conductive lines. The method for manufacturing a conductive line according to claim 1, wherein the conductive adhesive is one of conductive silver glue, conductive copper glue and conductive graphite glue. The method for fabricating a conductive line according to claim 1, wherein the conductive paste is etched by laser etching to form a plurality of conductive lines. A method of fabricating a conductive line according to claim 3, wherein the laser beam of the laser etching mode is a green laser of a wavelength of 532 nm or 1064 nm. The method for fabricating a conductive line according to claim 1, wherein the substrate is a transparent organic substrate or a transparent inorganic substrate, wherein the transparent organic substrate is polyethylene terephthalate, polycarbonate, and poly One of ethylene and polymethyl methacrylate.