CN111916251A - Low sheet resistance transparent conductive film - Google Patents

Abstract

The invention discloses a low square resistance transparent conductive film, which comprises a transparent substrate, a refractive index matching layer, a transition layer, a metal alloy layer, a dielectric barrier layer and a transparent conductive layer stacked from bottom to top. A water and oxygen barrier layer on the substrate side is added between the metal alloy layers, which is composed of a refractive index matching layer and a transition layer. The purpose of the transition layer is to provide a dense and continuous conductive layer for the upper metal alloy layer. The substrate can reduce the island-like discontinuity of the thin-layer metal. After it is combined with the refractive index matching layer made of high refractive index material to form a water-oxygen barrier layer on the substrate side, it can effectively prevent the metal alloy layer from deteriorating during use. , which greatly improves the reliability and weather resistance of the overall conductive film. At the same time, the invention adds a dielectric barrier layer with a dense molecular structure on the air side of the metal alloy layer, which effectively isolates water and oxygen corrosion, and greatly improves the ring resistance.

Description

Low square resistance transparent conductive film

technical field

The invention relates to the field of conductive films, in particular to a low square resistance transparent conductive film.

Background technique

In recent years, with the rapid development of semiconductor manufacturing technology and photovoltaic technology, technologies such as flat panel displays, touch screens, window films, polymer dispersed liquid crystals, and solar cells have developed and improved rapidly. These new technologies require the use of transparent conductive films. As electrodes, light-receiving surfaces or electromagnetic pulse shielding films. Taking a touch screen as an example, several types of touch screens commonly used, such as a resistive touch screen, a surface capacitive touch screen, and an inductive capacitive touch screen, all need to use a transparent conductive film as an electrode material.

Transparent conductive films are generally defined as being transparent in the visible light range and having low resistivity. Currently commonly used transparent conductive films include ITO (a mixture of tin oxide and indium oxide) film, AZO (aluminum-doped zinc oxide) film, and aluminum oxide.

After literature search, it was found that in 1998, M. Bender and W. Seelig et al. wrote "Dependence of film composition and thickness on optical and electrical properties of ITO-metal-ITO multilayers" in "Thin solidFilms" 326 (1998) 67-71. The relationship between the photoelectric properties of ITO-metal-ITO multilayer film and its film thickness and composition)”, the problem is that ITO/AG/ITO (I/M/I) multilayer film replaces a single ITO film in an attempt to obtain better electrical conductivity performance and lower cost. However, the optoelectronic properties of this sandwich structure failed to meet people's expectations. After that, a research group from Shanghai Jiao Tong University proposed a sandwich structure of dielectric layer/metal layer/dielectric layer, which has good conductivity and low resistance. However, the film with this structure still has a thick thickness, is easy to fall off on the flexible substrate PET, has poor adhesion, and is exposed to the air, the structure is unstable, the anti-oxidation ability is poor, and the weather resistance test 500h, the data is poor.

For example, taking the above-mentioned conductive film with a square resistance of about 15 ohms made of mature ITO in the industry as an example, the thickness of ITO is about 130 nm or more, and the thickness leads to poor bendability, which makes the flexible substrate basically unusable. The silver laminated conductive film successfully solves this problem, and the cost will be reduced. The disadvantage is that the weather resistance and transmittance of the silver laminated conductive film are slightly worse than ITO.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a low square resistance transparent conductive film with better weather resistance and transmittance, so as to make up for the deficiencies of the prior art in this area.

The technical scheme of the present invention is realized as follows:

The present invention provides a low square resistance transparent conductive film, a low square resistance transparent conductive film, comprising a transparent substrate, a refractive index matching layer, a transition layer, a metal alloy layer, a dielectric barrier layer and a layer stacked from bottom to top. transparent conductive layer,

The refractive index matching layer is a zinc sulfide layer, a niobium pentoxide layer, a titanium dioxide layer, a zinc oxide layer or a zinc oxide mixed layer, with a thickness of 15-50 nm, and the transition layer is one of magnesium oxide, gallium oxide and aluminum oxide. at least one zinc oxide mixed layer mixed with zinc oxide, the thickness is 3-15nm,

The dielectric barrier layer is a zinc oxide layer, or a nickel-chromium nitride layer, or a nickel-chromium oxynitride layer, with a thickness of 1-10 nm.

In certain embodiments, the index matching layer is a niobium pentoxide layer with a thickness of 35 nm.

In certain embodiments, the transition layer is a zinc magnesium oxide layer, a zinc gallium oxide layer, or a zinc aluminum oxide layer.

In certain embodiments, the transition layer is a zinc-magnesium oxide layer with a thickness of 6 nm.

In some embodiments, the dielectric barrier layer is a nickel-chromium oxynitride layer with a thickness of 3 nm.

In some embodiments, the material of the transparent substrate layer is one of PI, PET, PC, COP and glass, and the thickness is 0.005-1 μm, and when the material is PET or PC, the upper and lower surfaces are hardened deal with.

In certain embodiments, the material of the transparent substrate layer is PET, and the thickness is 0.125 μm.

In certain embodiments, the metal alloy layer is a silver alloy layer or a copper alloy layer, the remaining alloy components in the silver alloy are at least one of palladium, gold, copper, platinum, and rhodium, and the proportion of silver is greater than 95% The remaining alloy components in the copper alloy are at least one of palladium, gold, silver, platinum and rhodium, and the proportion of copper is greater than 95%; the thickness of the metal alloy layer is 4-20nm, and the square resistance is 5-30Ω.

In certain embodiments, the remaining alloys in the silver alloy layer are palladium and copper, the thickness of the silver alloy layer is 6.5 nm, and the square resistance is 16Ω.

In some embodiments, the transparent conductive layer is a tin oxide layer, or an indium tin oxide layer, the indium tin ratio is 90:10, and the thickness is 20-80 nm.

In some embodiments, the transparent conductive layer is an indium tin oxide layer with an indium tin ratio of 90:10 and a thickness of 40 nm.

In certain embodiments, the proportion of zinc oxide in the hybrid material in the transition layer is greater than 80%.

The advantages of the present invention are:

(1) The low square resistance transparent conductive film provided by the present invention adds a water and oxygen barrier layer on the substrate side which is composed of the refractive index matching layer and the transition layer between the transparent substrate and the metal alloy layer, wherein The purpose of the transition layer is to provide a dense and continuous conductive layer substrate for the upper metal alloy layer to reduce the island-like discontinuity of the thin metal layer, which is combined with the refractive index matching layer made of high refractive index material to form a substrate After the water and oxygen barrier layer on the side, the metal alloy layer is effectively prevented from deteriorating during use, and the reliability and weather resistance of the overall conductive film are greatly improved.

(2) At the same time, the present invention adds a dielectric barrier layer with a dense molecular structure on the air side of the metal alloy layer, which effectively isolates water and oxygen from the metal alloy through the first transparent conductive layer on the air side during processing and transportation. The water and oxygen erosion of the layer greatly improves the ring resistance.

Description of drawings

FIG. 1 is a schematic structural diagram of the present invention.

Example: The low square resistance transparent conductive film provided in this case has a laminated structure as shown in Figure 1, which has a transparent substrate 10, a refractive index matching layer 11, a transition layer 12, and a metal alloy layer stacked from bottom to top. 13. For the dielectric barrier layer 14 and the transparent conductive layer 15, various embodiments can be formed by selecting different materials, composition contents, or thicknesses of each layer. Below we illustrate our products and their performance with six examples:

Example 1

The low square resistance transparent conductive film is composed of a transparent substrate 10, an index matching layer 11, a transition layer 12, a metal alloy layer 13, a dielectric barrier layer 14 and a transparent conductive layer 15 stacked from bottom to top. The materials of each layer are respectively It is PET, niobium pentoxide, zinc magnesium oxide, silver alloy (the remaining alloys in the silver alloy are palladium and copper, the proportion of silver is greater than 95%, and the square resistance is 16Ω), nickel oxynitride (nickel-chromium adopts the weight ratio 50:50 to 95:5 can be used, preferably 80:20), indium tin oxide (indium tin ratio 90:10), and the thicknesses of the above layers are 0.125 μm, 35 nm, 6 nm, 6.5 nm, 3 nm, and 40 nm, respectively. At this time, the transparent conductive film has better properties (including weather resistance, transparency, adhesion, etc.).

The production process can adopt the conventional roll-to-roll magnetron sputtering deposition method, and the roll-to-roll magnetron sputtering deposition method can sputter a variety of materials, with high vacuum degree, strong adhesion, dense film material, and can be used in flexible Coating on the substrate.

For example, in this embodiment, the niobium pentoxide target, the zinc-magnesium oxide target, the silver-palladium-copper alloy target, the nickel-chromium target, and the indium-tin oxide target are sequentially purchased on the flexible PET transparent substrate. , deposited by magnetron sputtering process. Wherein, in the process of sputtering the nickel-chromium target, nitrogen and oxygen are introduced to form a nickel-chromium oxynitride layer.

When the material is PET or PC, the upper and lower surfaces are hardened by a coating process such as HC hardening layer, which is a conventional technique and will not be repeated here.

Of course, the transparent conductive film can also be performed by other process methods, such as chemical vapor deposition or physical vapor deposition, etc. The process and process parameters thereof can refer to the prior art, which will not be repeated here.

Tables 1 and 2 are the test results of the product of Example 1

Table 1

Square resistance Ω VLT(%) adhesion 16Ω 85% 5B

Weather resistance test conditions: high temperature and high humidity: 85°C, 85% RH, high temperature storage: 80°C, low temperature storage: -40°C, thermal shock: -40°C (60min) to 80°C (60min), 20cycles, the results are as follows Table 2

Table 2

Example 2

The low square resistance transparent conductive film is composed of a transparent substrate 10, an index matching layer 11, a transition layer 12, a metal alloy layer 13, a dielectric barrier layer 14 and a transparent conductive layer 15, which are stacked from bottom to top. They are PC, zinc sulfide, zinc gallium oxide, copper alloy (the remaining alloys in the copper alloy are palladium and gold, the proportion of copper is more than 95%, and the square resistance is 18Ω), zinc oxide, and tin oxide. The thicknesses of the above layers are respectively 0.100 μm, 40 nm, 7 nm, 5.5 nm, 5 nm, 42 nm.

Tables 3 and 4 are the test results of the product of Example 2

table 3

Square resistance Ω VLT(%) adhesion 18 82 5B

Weather resistance test conditions: high temperature and high humidity: 85°C, 85% RH, high temperature storage: 80°C, low temperature storage: -40°C, thermal shock: -40°C (60min) to 80°C (60min), 20cycles, the results are as follows Table 4

Table 4

Example 3

The low square resistance transparent conductive film is composed of a transparent substrate 10, an index matching layer 11, a transition layer 12, a metal alloy layer 13, a dielectric barrier layer 14 and a transparent conductive layer 15, which are stacked from bottom to top. They are PI, titanium dioxide, zinc gallium oxide, silver alloy (the remaining alloys in the silver alloy are platinum and rhodium, the proportion of silver is more than 95%, and the square resistance is 14Ω), nickel-chromium nitride, indium-tin oxide (indium-tin ratio 90:10), the thicknesses of the above layers are 0.150 μm, 30 nm, 5 nm, 7 nm, 2 nm, and 28 nm, respectively.

Tables 5 and 6 are the test results of the product of Example 3

table 5

Square resistance Ω VLT(%) adhesion 14 83 5B

Weather resistance test conditions: high temperature and high humidity: 85°C, 85% RH, high temperature storage: 80°C, low temperature storage: -40°C, thermal shock: -40°C (60min) to 80°C (60min), 20cycles, the results are as follows Table 6

Table 6

Example 4

The low square resistance transparent conductive film is composed of a transparent substrate 10, an index matching layer 11, a transition layer 12, a metal alloy layer 13, a dielectric barrier layer 14 and a transparent conductive layer 15, which are stacked from bottom to top. They are COP, zinc oxide, zinc-magnesium oxide, copper alloy (the remaining alloys in the copper alloy are palladium and platinum, the proportion of copper is greater than 95%, and the square resistance is 18Ω), zinc oxide, and tin oxide. The thicknesses of the above layers are respectively 0.120 μm, 40 nm, 5 nm, 6 nm, 8 nm, 32 nm.

Tables 7 and 8 are the test results of the product of Example 4

Table 7

Square resistance Ω VLT(%) adhesion 18 82 5B

Weather resistance test conditions: high temperature and high humidity: 85°C, 85% RH, high temperature storage: 80°C, low temperature storage: -40°C, thermal shock: -40°C (60min) to 80°C (60min), 20cycles, the results are as follows Table 8

Table 8

Example 5

The low square resistance transparent conductive film is composed of a transparent substrate 10, an index matching layer 11, a transition layer 12, a metal alloy layer 13, a dielectric barrier layer 14 and a transparent conductive layer 15, which are stacked from bottom to top. They are glass, zinc oxide, zinc oxide aluminum, silver alloy (the remaining alloys in the copper alloy are gold and platinum, the proportion of copper is more than 95%, and the square resistance is 12Ω), nickel chromium nitride, indium tin oxide (indium tin oxide) ratio 90:10), the thicknesses of the above-mentioned layers are 0.085 μm, 45 nm, 10 nm, 3 nm, 10 nm, and 30 m, respectively.

Tables 9 and 10 are the test results of the product of Example 5

Table 9

Square resistance Ω VLT(%) adhesion 12 80 5B

Weather resistance test conditions: high temperature and high humidity: 85°C, 85% RH, high temperature storage: 80°C, low temperature storage: -40°C, thermal shock: -40°C (60min) to 80°C (60min), 20cycles, the results are as follows Table 10

Table 10

Example 6

The low square resistance transparent conductive film is composed of a transparent substrate 10, an index matching layer 11, a transition layer 12, a metal alloy layer 13, a dielectric barrier layer 14 and a transparent conductive layer 15, which are stacked from bottom to top. They are PET, titanium dioxide, zinc gallium oxide, copper alloy (the remaining alloys in the copper alloy are gold and rhodium, the proportion of copper is more than 95%, and the square resistance is 10Ω), nickel-chromium nitride, indium-tin oxide (indium-tin ratio 90:10), the thicknesses of the above layers are 0.135 μm, 30 nm, 9 nm, 11 nm, 3 nm, and 35 m, respectively.

Tables 11 and 12 are the test results of the products of Example 6

Table 11

Square resistance Ω VLT(%) adhesion 10 89 5B

Weather resistance test conditions: high temperature and high humidity: 85°C, 85% RH, high temperature storage: 80°C, low temperature storage: -40°C, thermal shock: -40°C (60min) to 80°C (60min), 20cycles, the results are as follows Table 12

Table 12

Of course, the above-mentioned embodiments are only intended to illustrate the technical concept and characteristics of the present invention, and the purpose thereof is to enable those who are familiar with the art to understand the content of the present invention and implement it accordingly, and cannot limit the protection scope of the present invention by this. All modifications made according to the spirit and essence of the main technical solutions of the present invention should be covered within the protection scope of the present invention.

Claims (10)

1. A low sheet resistance transparent conductive film is characterized in that: comprises a transparent substrate, a refractive index matching layer, a transition layer, a metal alloy layer, a medium barrier layer and a transparent conducting layer which are stacked from bottom to top,

wherein the refractive index matching layer is a zinc sulfide layer, a niobium pentoxide layer, a titanium dioxide layer, a zinc oxide layer or a zinc oxide mixed layer, the thickness is 15-50 nm,

the transition layer is a zinc oxide mixed layer formed by mixing zinc oxide with at least one of magnesium oxide, gallium oxide and aluminum oxide, the thickness of the zinc oxide mixed layer is 3-15 nm,

the medium barrier layer is a zinc oxide layer, or a nickel-chromium nitride layer, or a nickel-chromium oxynitride layer, and the thickness is 1-10 nm.

2. The transparent conductive film with low sheet resistance according to claim 1, wherein: the refractive index matching layer is a niobium pentoxide layer and has a thickness of 35 nm.

3. The transparent conductive film with low sheet resistance according to claim 1, wherein: the transition layer is a zinc magnesium oxide layer and is 6nm thick.

4. The transparent conductive film with low sheet resistance according to claim 1, wherein: the medium barrier layer is a nickel-chromium oxynitride layer, and the thickness is 3 nm.

5. The transparent conductive film with low sheet resistance according to claim 1, wherein: the transparent substrate layer is made of one of PI, PET, PC, COP and glass, the thickness of the transparent substrate layer is 0.005-1 mu m, and when the transparent substrate layer is made of PET or PC, the upper surface and the lower surface of the transparent substrate layer are hardened.

6. The transparent conductive film with low sheet resistance according to claim 5, wherein: the transparent substrate layer is made of PET and has a thickness of 0.125 μm.

7. The transparent conductive film with low sheet resistance according to claim 1, wherein: the metal alloy layer is a silver alloy layer or a copper alloy layer, the rest alloy components in the silver alloy are at least one of palladium, gold, copper, platinum and rhodium, and the proportion of silver is more than 95%; the other alloy components in the copper alloy are at least one of palladium, gold, silver, platinum and rhodium, and the proportion of copper is more than 95 percent; the thickness of the metal alloy layer is 4-20 nm, and the sheet resistance is 5-30 omega.

8. The transparent conductive film with low sheet resistance according to claim 7, wherein: the rest alloy in the silver alloy layer is palladium and copper, the thickness of the silver alloy layer is 6.5nm, and the sheet resistance is 16 omega.

9. The transparent conductive film with low sheet resistance according to claim 1, wherein: the transparent conducting layer is a tin oxide layer or an indium tin oxide layer, the ratio of indium to tin is 90:10, and the thickness is 20-80 nm.

10. The transparent conductive film with low sheet resistance according to claim 9, wherein: the transparent conducting layer is an indium tin oxide layer, the indium tin ratio is 90:10, and the thickness is 40 nm.

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