CN104637573A - Conductive film structure - Google Patents

Abstract

The invention discloses a conductive film structure. The conductive film structure includes a substrate and a conductive mesh pattern . The conductive mesh pattern is disposed on the substrate. The conductive mesh pattern has a plurality of conductive lines and a plurality of conductive connection portions, wherein the plurality of conductive connection portions connect the plurality of conductive lines to each other to form the conductive mesh pattern. The conductive wire has a first thickness, and the conductive connecting portion has a second thickness, and the first thickness is different from the second thickness.

Description

Conductive film structure

technical field

The invention relates to a conductive film structure, and in particular to a conductive film structure with a conductive mesh pattern.

Background technique

In current main touch sensing devices, indium tin oxide (ITO) films are mostly used to make transparent conductive sensing layers. However, the manufacturing process temperature of the ITO thin film cannot be too high, so its impedance cannot be reduced to a very low level, so when a large-area ITO thin film is applied to a large-sized sensing device, the large-area ITO The impedance generated by the oxide film cannot match its corresponding integrated circuit, and the high surface resistance will reduce the sensing sensitivity of the sensing device. Furthermore, the indium tin oxide thin film is brittle and easily cracks when bent, which not only has a bad effect on its conductivity, but is also not suitable for application in flexible devices with flexibility. In addition, indium is a rare material with a high price, which is not conducive to cost control.

Therefore, how to provide a conductive thin film of a touch sensing device with good characteristics is one of the subjects that relevant practitioners are striving for.

Contents of the invention

The content of the present invention relates to a conductive film structure. In the conductive thin film structure of the embodiment, the thickness of the wire passing through the conductive mesh pattern is different from the design of the thickness of the conductive connection part, so that the wire and the conductive connection part have different light transmittance and reflectivity, thereby improving the overall visibility .

According to an embodiment of the disclosure, a conductive film structure is provided. The conductive film structure includes a substrate and a conductive metal mesh. The conductive mesh pattern is disposed on the substrate. The conductive mesh pattern includes a plurality of wires and a plurality of conductive connection parts, wherein the plurality of conductive connection parts connect the plurality of wires to form the conductive mesh pattern. The wire has a first thickness, the conductive connection part has a second thickness, and the first thickness is different from the second thickness.

According to another embodiment of the disclosure, a touch panel is provided. The touch panel includes a substrate and a touch electrode. The touch electrodes are disposed on the substrate. The touch electrode is formed by a conductive mesh pattern, and the conductive mesh pattern includes a plurality of wires and a plurality of conductive connection parts, wherein the plurality of conductive connection parts connect the plurality of wires to each other to form the conductive mesh pattern. The wire has a first thickness, the conductive connection part has a second thickness, and the first thickness is different from the second thickness.

In order to have a better understanding of the above-mentioned and other aspects of the present invention, the preferred embodiments are specifically cited below, together with the accompanying drawings, and described in detail as follows:

Description of drawings

Fig. 1 is the top view of the conductive film structure of an embodiment of the content of the present invention;

FIG. 2A is a partial top view of a conductive thin film structure according to an embodiment of the present invention;

Fig. 2B is a schematic cross-sectional view along the section line 2B-2B' of Fig. 2A.

Symbol Description

10: Conductive film structure

100: Substrate

200: conductive mesh pattern

210: wire

230: Conductive connection part

T1: first thickness

T2: second thickness

W1: first width

W2: second width

2B-2B': hatching

Detailed ways

According to an embodiment of the present invention, in the conductive thin film structure, the thickness of the wire passing through the conductive mesh pattern is different from the design of the thickness of the conductive connection part, so that the wire and the conductive connection part have different light transmittance and reflectivity, thereby improving overall visibility. Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The same reference numerals are used in the drawings to designate the same or similar parts. It should be noted that the drawings have been simplified to clearly illustrate the content of the embodiments, and the detailed structures proposed in the embodiments are for illustration purposes only, and are not intended to limit the protection scope of the present invention. Those with ordinary knowledge can modify or change these structures according to the needs of actual implementation.

1 shows a top view of a conductive thin film structure 10 according to an embodiment of the present invention, FIG. 2A shows a partial top view of a conductive thin film structure 10 according to an embodiment of the present invention, and FIG. 2B shows a section line 2B along FIG. 2A - Schematic cross-section of 2B'. Referring to FIGS. 1-2B , the conductive film structure 10 includes a substrate 100 and a conductive metal mesh 200 . The conductive mesh pattern 200 is disposed on the substrate 100 . The conductive mesh pattern 200 includes a plurality of conductive wires 210 and a plurality of conductive connection portions 230 , wherein the plurality of conductive connection portions 230 connect the plurality of conductive wires 210 to form the conductive mesh pattern 200 . The wire 210 has a first thickness T1, the conductive connection part 230 has a second thickness T2, and the first thickness T1 is different from the second thickness T2. Due to the difference in the thicknesses T1 and T2 of the two, the wire 210 and the conductive connecting portion 230 have different light transmittance and reflectivity, thereby improving overall visibility. It should be noted that the dimensional ratios of the first thickness T1 and the second thickness T2 in the drawings are not drawn according to the same proportion of the actual product, but are only used to clearly illustrate the content of the embodiment, and therefore are not intended to limit the scope of protection of the content of the present invention for.

In an embodiment, the conductive mesh pattern 200 can be fabricated by methods such as gravure printing, grayscale masking or nanoimprinting, and can adopt a planar manufacturing process or a roll-to-roll manufacturing process.

In one embodiment, as shown in the top view of FIG. 2A , it is likely that the unit area of the conductive connection portion 230 is larger than the unit area of the wire 210 due to incomplete development and etching during the manufacturing process, and the conductive connection portion 230 The second width W2 is greater than the first width W1 of the metal wire 210 , so the conductive connection portion 230 has a visibility problem due to its larger light reflection area. In one embodiment, the width of the wire 210 may be 1-20 micrometers (μm), preferably 3-10 micrometers (μm). The width of the conductive connection portion 230 is at least √2 times the width of the wire 210 , and the planar shape of the conductive connection portion 230 is substantially a rectangle with concave edges. In the embodiment of the present invention, the second thickness T2 of the conductive connection part 230 is smaller than the first thickness T1 of the metal wire 210, in addition to improving the overall light transmittance of the conductive mesh pattern 200, it can also reduce the thickness of the conductive mesh pattern 200 at the same time. The reflectivity makes the color rendering of the conductive mesh pattern 200 less obvious, thereby improving the visibility problem at the conductive connection portion 200 having a larger width. In other words, compared with the conductive mesh pattern with the same overall thickness (the thickness of the conductive connection part 230 and the thickness of the conductive wire 210 ) and having a large-area conductive connection part, the aperture ratio and light transmittance caused by the large-area conductive connection part decrease. And the problem of high reflectivity can be greatly improved.

It should be noted that, in the embodiment where the second thickness T2 of the conductive connection part 230 is smaller than the first thickness T1 of the wire 210, the second thickness T2 of the conductive connection part 230 should also have a minimum value, and it cannot be reduced without limit. Small. When the second thickness T2 of the conductive connection part 230 is smaller than the first thickness T1 of the wire 210 , the conductive connection part 230 must still maintain a certain thickness so that the metal mesh 200 can have predetermined conductivity.

In one embodiment, the ratio of the first thickness T1 of the wire 210 to the second thickness T2 of the conductive connection portion 230 is, for example, in the range of 2:1˜50:1. For example, when the first thickness T1 of the wire 210 is 200 nanometers (nm), the second thickness T2 of the conductive connection part 230 may be 4˜100 nanometers (nm). However, in practical applications, the numerical ranges of the first thickness T1 and the second thickness T2 are also appropriately selected depending on the application conditions, and are not limited to the aforementioned numerical ranges.

In one embodiment, the second thickness T2 of the conductive connection portion 230 is, for example, 5˜150 nanometers (nm).

In one embodiment, the difference between the first thickness T1 of the wire 210 and the second thickness T2 of the conductive connection portion 230 is, for example, 50˜2000 nanometers (nm). In another embodiment, taking the material of the conductive mesh pattern 200 as silver metal as an example, when the first thickness T1 of the wire 210 is 200 nanometers, the second thickness T2 of the conductive connection part 230 may be 20-100 nanometers, for example, these two The difference between them is 100-180 nanometers. However, in actual application, the material of the conductive mesh pattern 200 , and the value ranges of the first thickness T1 and the second thickness T2 are also selected appropriately depending on the application conditions, and are not limited to the aforementioned materials and value ranges.

In the embodiment, the material of the conductive mesh pattern 200 is conductive metal. For example, the material of the metal mesh 200 may include at least one of silver, copper, aluminum and molybdenum.

In an embodiment, the substrate 100 is, for example, a flexible substrate or a glass substrate.

In one embodiment, the conductive thin film structure described in the disclosure can be applied to a touch panel, for example. The touch panel includes a substrate and a touch electrode, and the touch electrode is disposed on the substrate. In the embodiment, the touch electrode is formed by, for example, the aforementioned conductive mesh pattern 200, the wires of the conductive mesh pattern 200 have a first thickness, and the conductive connection part of the conductive mesh pattern 200 has a second thickness, and the first thickness is different from the first thickness. Two thickness.

The following examples will be further described. The material, size and simulation results of the conductive mesh pattern 200 of an embodiment are listed below. However, the following examples are for illustrative purposes only, and should not be construed as limitations on the implementation of the content of the present invention.

Table 1 lists the simulation results of the second thickness T2 relative to the reflectivity obtained by using silver metal as the material of the conductive mesh pattern 200 and keeping the impedance at a constant value. In the embodiment shown in Table 1, the first width W1 of the wire 210 is 8 micrometers (μm), the second width W2 of the intersection portion 230 is 36 micrometers, and the first thickness T1 of the wire 210 is 200 nanometers.

Table 1

Second thickness T2 (nm) Reflectivity(%)

200 98.17 150 98.17 120 98.15 100 98.07 80 97.74 60 96.29 50 94.23 40 89.91 30 80.89 20 62.64

As shown in Table 1, when the second thickness T2 of the conductive connection part 230 decreases, the reflectivity also decreases. For example, when the thickness of the conductive connecting portion 230 is reduced from 200 nm to 20 nm, the reflectivity can be greatly reduced from 98.17% to 62.64%. In other words, according to the simulation results described in Table 1, in the embodiment, the material of the conductive mesh pattern 200 is silver, and the second thickness T2 is, for example, 20-100 nanometers, then the conductive connection part 230 has a reflection lower than that of the wire 210. Rate. In another embodiment, the conductive mesh pattern 200 is made of copper, the first thickness T1 is, for example, 200 nanometers, and the second thickness T2 is, for example, 30-80 nanometers, and the conductive connection portion 230 may have a lower reflectivity than the wire 210 . However, in actual application, the value range of the second thickness T2 can also be appropriately selected depending on the application situation. For example, the first thickness T1 adopted according to the material of the conductive mesh pattern 200 and the conductive wire 210 is not limited to the above-mentioned value.

Furthermore, to maintain the impedance at a constant value, the area and thickness of the conductive metal are roughly inversely proportional. For example, when the material of the conductive mesh pattern 200 is silver, the first width W1 of the wire 210 is 8 micrometers, the second width W2 of the conductive connection part 230 is 36 micrometers, and the first thickness T1 of the wire 210 is 200 nanometers, according to According to calculations, when the second thickness T2 of the conductive connecting portion 230 with an area of 36×36 square micrometers is reduced to about 20 nanometers, it can have an impedance matching that of the metal wire 210 with an area of 8×8 square micrometers.

To sum up, in the process of manufacturing the conductive mesh pattern 200, although the conductive connection part 230 may have a larger area than the conductive wire 210 due to incomplete development and etching in the manufacturing process, by changing the area of the conductive connection part 230 The second thickness T2 can still make the conductive connection part 230 and the wire 210 have matching impedance, and achieve good light transmittance and low reflectivity, and thus have good visibility.

In summary, although the present invention has been disclosed in conjunction with the above preferred embodiments, they are not intended to limit the present invention. Those skilled in the art to which the present invention belongs can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be defined by the appended claims.

Claims (9)

1. A conductive film structure, comprising: substrate; and A conductive mesh pattern (conductive mesh pattern) is arranged on the substrate, and it includes a plurality of wires and a plurality of conductive connection parts, wherein the plurality of conductive connection parts connect the plurality of wires to each other to form the conductive mesh pattern, Wherein the wires have a first thickness, the conductive connecting parts have a second thickness, and the first thickness is different from the second thickness. 2. The conductive film structure as claimed in claim 1, wherein the first thickness is greater than the second thickness. 3. The conductive thin film structure as claimed in claim 2, wherein the ratio of the first thickness to the second thickness is 2:1˜50:1 and not equal to 1. 4. The conductive film structure as claimed in claim 1, wherein a difference between the first thickness and the second thickness is 50-2000 nanometers (nm). 5. The conductive film structure as claimed in claim 1, wherein the second thickness is 20-2000 nanometers (nm). 6. The conductive film structure as claimed in claim 1, wherein the wire has a width of 1-20 microns (μm). 7. The conductive film structure as claimed in claim 1, wherein the width of the conductive connection part is greater than √2 times the width of the wire. 8 . The conductive thin film structure as claimed in claim 1 , wherein the planar shape of the conductive connecting portion is substantially a rectangle with concave edges. 9. A touch panel, comprising: substrate; and The touch electrode is arranged on the substrate, wherein the touch electrode is formed by a conductive mesh pattern, and the conductive mesh pattern includes a plurality of wires and a plurality of conductive connection parts, wherein the plurality of conductive connection parts connect the plurality of wires to each other connected to form the conductive mesh pattern, wherein the wire has a first thickness, the conductive connection part has a second thickness, and the first thickness is different from the second thickness.