High-water vapor barrier rate low-resistance ITO (indium tin oxide) film and preparation method thereof
By designing a composite barrier layer and a dense hydrophobic layer on the ITO film, the problem of electrochemical corrosion of the ITO film in a high humidity environment was solved, and an ITO film with high water vapor barrier rate and low resistance was achieved, while maintaining conductivity and light transmittance. Moreover, the process is simple and the cost is controllable.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-24
- Publication Date
- 2026-04-07
AI Technical Summary
Traditional ITO films are prone to electrochemical corrosion in high humidity environments, which leads to abnormally high resistance, affecting device reliability and lifespan. Existing improvement methods either result in decreased light transmittance or increased costs, or it is difficult to achieve a balance between moisture barrier performance and conductivity.
The design employs a composite barrier layer and a dense hydrophobic layer, including coating layers on both sides of the substrate, a composite barrier layer composed of silicon nitride, silicon dioxide and niobium pentoxide, and a fluorinated alkylsilane dense hydrophobic layer. The ITO layer is prepared by combining magnetron sputtering and vacuum evaporation technology. The edge of the ITO layer is provided with isolation grooves and conductive sealing layers to enhance protection.
It achieves high water vapor barrier performance and excellent photoelectric properties, maintains the conductivity and light transmittance of ITO, and improves the mechanical stability and environmental durability of the film. The process is simple and the cost is controllable.
Smart Images
Figure CN121806168A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of ITO membrane technology, specifically to a high water vapor barrier rate and low resistance ITO membrane and its preparation method. Background Technology
[0002] ITO thin films are widely used as transparent electrodes in optoelectronic devices such as flat panel displays, touch screens, and solar photovoltaic cells due to their excellent conductivity and high transmittance in the visible light region. However, traditional ITO thin films are prone to electrochemical corrosion in high humidity environments, leading to abnormally high resistance and even functional failure, severely affecting the reliability and lifespan of devices in harsh environments. To improve the weather resistance of ITO thin films, existing technologies mainly focus on two directions: one is to increase the ITO film thickness to physically block water vapor intrusion, but this leads to decreased transmittance and increased cost, and thick films are prone to cracking on flexible substrates; the other is to add a separate barrier film outside the ITO layer. For example, some technologies use multiple layers of inorganic materials such as SiO2 and polymers alternately stacked to form an ultra-high barrier film, with a water vapor transmission rate (WVTR) of up to 10. -5 While ITO films can effectively protect sensitive devices such as OLEDs at the g / m² / day level, such structures typically do not directly possess the conductive properties of ITO. These methods or processes are complex and costly, or they sacrifice the surface smoothness and conductivity of the ITO film in pursuit of superhydrophobicity, or it is difficult to achieve the optimal balance between barrier performance and optical performance.
[0003] Therefore, there is an urgent need to develop an ITO membrane that is simple to process, cost-controllable, and can achieve excellent levels in both water vapor barrier performance and conductivity. Summary of the Invention
[0004] The purpose of this invention is to provide a high water vapor barrier rate and low resistance ITO membrane and its preparation method, so as to solve the problems mentioned in the background art.
[0005] To achieve the above objectives, the present invention provides the following technical solution: A high water vapor barrier, low-resistance ITO membrane, characterized in that it comprises: A substrate having an upper coating layer and a lower coating layer on both sides; A composite barrier layer is disposed on the upper coating layer, and the composite barrier layer comprises, from bottom to top, a first high refractive index inorganic oxide layer, a silicon dioxide layer, and a second high refractive index inorganic oxide layer. An ITO layer is disposed on the second high-refractive-index inorganic oxide layer; A dense hydrophobic layer is disposed on the ITO layer.
[0006] Preferably, the materials of the upper coating layer and the lower coating layer are an acrylic resin mixture, the thickness of the upper coating layer is 800-1100 nm, and the thickness of the lower coating layer is 500-800 nm.
[0007] Preferably, the material of the first high-refractive-index inorganic oxide layer is silicon nitride, and the thickness of the first high-refractive-index inorganic oxide layer is 6-10 nm.
[0008] Preferably, the thickness of the silicon dioxide layer is 40-60 nm.
[0009] Preferably, the material of the second high-refractive-index inorganic oxide layer is niobium pentoxide, and the thickness of the second high-refractive-index inorganic oxide layer is 6-10 nm.
[0010] Preferably, the ITO layer has a thickness of 100-200 nm, and the dense hydrophobic layer is made of fluoroalkylsilane.
[0011] Preferably, the material of the substrate can be one of PET, PC or PI.
[0012] Preferably, the edge of the ITO layer is provided with a partition groove, and the ITO layer is provided with a dividing groove at intervals, the dividing groove dividing the ITO layer into several independent ITO blocks.
[0013] Preferably, the partition groove is provided with an edge sealing layer, and the dividing groove is provided with a conductive sealing layer, the conductive sealing layer connecting the ITO blocks on both sides.
[0014] A method for preparing a high water vapor barrier and low resistance ITO membrane based on any one of the above-mentioned methods, comprising: S1: Dry the substrate; S2: Apply an acrylic resin mixture evenly to one side of the substrate and bake at a low temperature of 60-80 degrees Celsius for 30 minutes. S3: Turn the substrate over, apply acrylic resin mixture evenly to the substrate again, and bake at a low temperature of 60-80 degrees Celsius for 30 minutes. S4: Silicon nitride, silicon dioxide, and niobium pentoxide are deposited sequentially using physical vapor deposition to form the first high-refractive-index inorganic oxide layer, the silicon dioxide layer, and the second high-refractive-index inorganic oxide layer. S5: The substrate temperature is controlled at 50-70°C, and indium tin oxide is deposited by magnetron sputtering in 5-8 stages to form the ITO layer; S6: Use a laser to etch the partition groove along the edge of the long side of the ITO layer, and use a laser to etch a plurality of the dividing grooves sequentially along the short side of the ITO layer; S7: Deposit metallic silver in the dividing groove using magnetron sputtering to form the conductive sealing layer; S8: A fluoroalkyl silane film is deposited in the partition groove using a vacuum evaporation method to form the edge sealing layer; S9: A second fluoroalkyl silane film is formed by vacuum evaporation on the ITO layer, the edge sealing layer and the conductive sealing layer to form the dense hydrophobic layer.
[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. Superior water vapor barrier performance: Through the synergistic design of "composite barrier layer + dense hydrophobic layer", multiple defenses against water vapor are achieved. The three-layer composite barrier layer inside provides a dense physical barrier that can effectively block the diffusion of water molecules. The outer dense hydrophobic layer changes the surface energy, repels liquid water, and prevents it from penetrating into the micro-defects of the film. This makes the overall water vapor barrier performance of the film far exceed that of traditional solutions with only a single layer of ITO or a single hydrophobic coating. 2. Excellent overall optoelectronic performance: While providing high water vapor barrier properties, this process retains the intrinsic advantages of ITO to the greatest extent. Optimized ITO deposition parameters ensure high crystallinity and low defect density of the film, resulting in low sheet resistance. At the same time, the specially designed composite barrier layer also has optical anti-reflection function, which, combined with the dense ITO layer, ensures high transmittance of the entire film system in the visible light range. 3. Good process compatibility and reliability: The entire preparation process is based on mature magnetron sputtering and vacuum evaporation technologies. The process is stable and repeatable, and it is easy to integrate and scale up in existing production lines. The prepared thin film has a dense structure, strong interlayer bonding, and good mechanical stability and environmental durability. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the structure of Embodiment 2 of the present invention; Figure 3 This is a schematic diagram of the exploded structure of Embodiment 2 of the present invention; Figure 4 This is a schematic diagram of the structure after concealing the dense hydrophobic layer and the edge sealing layer in Embodiment 2 of the present invention.
[0017] In the figure: 1. Substrate; 2. Upper coating layer; 3. Lower coating layer; 4. Composite barrier layer; 401. First high refractive index inorganic oxide layer; 402. Silicon dioxide layer; 403. Second high refractive index inorganic oxide layer; 5. ITO layer; 6. Dense hydrophobic layer; 7. Partition groove; 8. Dividing groove; 9. Edge sealing layer; 10. Conductive sealing layer. Detailed Implementation
[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0019] Please see Figures 1 to 4 The present invention provides a technical solution: Example 1: High water vapor barrier rate and low resistance ITO membrane, comprising: The substrate 1 has an upper coating layer 2 and a lower coating layer 3 on both sides. The substrate 1 is a flexible polymer substrate, which can be made of PET, PC, or PI. The upper coating layer 2 and the lower coating layer 3 are made of an acrylic resin mixture. The thickness of the upper coating layer 2 is 800-1100 nm, and the thickness of the lower coating layer 3 is 500-800 nm. The upper coating layer 2 and the lower coating layer 3 are used to improve the weather resistance, bending resistance, and water resistance of the film material.
[0020] The composite barrier layer 4 is disposed on the upper coating layer 2. The composite barrier layer 4 includes, from bottom to top, a first high refractive index inorganic oxide layer 401, a silicon dioxide layer 402, and a second high refractive index inorganic oxide layer 403. The material of the first high refractive index inorganic oxide layer 401 is silicon nitride, and the thickness of the first high refractive index inorganic oxide layer 401 is 6-10 nm. The thickness of the silicon dioxide layer 402 is 40-60 nm. The material of the second high refractive index inorganic oxide layer 403 is niobium pentoxide, and the thickness of the second high refractive index inorganic oxide layer 403 is 6-10 nm. This three-layer structure, through the combination of high and low refractive index materials, not only provides physical water vapor blocking but also plays an optical anti-reflection role, reducing the loss of interface reflected light.
[0021] ITO layer 5 is disposed on the second high refractive index inorganic oxide layer 403. The thickness of ITO layer 5 is 100-200 nm. ITO layer 5 has excellent crystallinity and low defect density.
[0022] Dense hydrophobic layer 6 is disposed on ITO layer 5. The material of dense hydrophobic layer 6 is fluoroalkyl silane. Fluoroalkyl silane (such as tridecafluorooctyltriethoxysilane) can form a low surface energy monomolecular film on the surface of ITO layer 5, giving the surface hydrophobicity, making it difficult for droplets to wet and adhere, thus forming the first line of defense against liquid water contact corrosion.
[0023] Example 2: The difference between Example 2 and Example 1 is that a partition groove 7 is provided at the edge of the ITO layer 5, and a dividing groove 8 is provided at intervals on the ITO layer 5. The dividing groove 8 divides the ITO layer 5 into several independent ITO blocks. The partition groove 7 is provided at the edge of the long side of the ITO layer 5, and several dividing grooves 8 are provided along the short side of the ITO layer 5.
[0024] An edge sealing layer 9 is provided in the partition groove 7, and a conductive sealing layer 10 is provided in the dividing groove 8. The conductive sealing layer 10 connects the ITO blocks on both sides. The thickness of the edge sealing layer 9 and the conductive sealing layer 10 is the same as that of the ITO layer 5. The edge sealing layer 9 and the conductive sealing layer 10 are used to prevent the edge of the ITO layer 5 from being electrochemically corroded. The conductive sealing layer 10 is made of silver or gold, which is relatively more resistant to electrochemical corrosion and has excellent conductivity. The conductive sealing layer 10 protects the ITO layer 5 while ensuring conductivity. The ITO film is divided into several parts from the center of the conductive sealing layer 10. The ITO film retains its conductivity while further improving its resistance to electrochemical corrosion.
[0025] Preparation method: The substrate 1 is dried. An acrylic resin mixture is uniformly coated on one side of the substrate 1 and baked at a low temperature of 60-80 degrees Celsius for 30 minutes. The substrate 1 is then flipped over, and the acrylic resin mixture is uniformly coated on the substrate 1 again and baked at a low temperature of 60-80 degrees Celsius for 30 minutes. Silicon nitride, silicon dioxide, and niobium pentoxide are deposited sequentially using physical vapor deposition to form a first high-refractive-index inorganic oxide layer 401, a silicon dioxide layer 402, and a second high-refractive-index inorganic oxide layer 403. The temperature of the substrate 1 is controlled at 50-70 degrees Celsius. At °C, indium tin oxide is deposited by magnetron sputtering in 5-8 stages to form an ITO layer 5. Isolation grooves 7 are etched along the long edge of the ITO layer 5 using a laser. Several dividing grooves 8 are etched sequentially along the short side of the ITO layer 5 using a laser. Metallic silver is deposited in the dividing grooves 8 by magnetron sputtering to form a conductive sealing layer 10. A fluorinated alkyl silane film is deposited in the isolation grooves 7 by vacuum evaporation to form an edge sealing layer 9. A second fluorinated alkyl silane film is deposited on the ITO layer 5, the edge sealing layer 9, and the conductive sealing layer 10 by vacuum evaporation to form a dense hydrophobic layer 6.
[0026] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A high water vapor barrier and low resistance ITO membrane, characterized in that, include: A substrate having an upper coating layer and a lower coating layer on both sides; A composite barrier layer is disposed on the upper coating layer, and the composite barrier layer comprises, from bottom to top, a first high refractive index inorganic oxide layer, a silicon dioxide layer, and a second high refractive index inorganic oxide layer. An ITO layer is disposed on the second high-refractive-index inorganic oxide layer; A dense hydrophobic layer is disposed on the ITO layer.
2. The high water vapor barrier rate and low resistance ITO membrane according to claim 1, characterized in that: The upper and lower coating layers are made of an acrylic resin mixture. The upper coating layer has a thickness of 800-1100 nm, and the lower coating layer has a thickness of 500-800 nm.
3. The high water vapor barrier rate and low resistance ITO membrane according to claim 1, characterized in that: The first high-refractive-index inorganic oxide layer is made of silicon nitride, and its thickness is 6-10 nm.
4. The high water vapor barrier rate and low resistance ITO membrane according to claim 1, characterized in that: The thickness of the silicon dioxide layer is 40-60 nm.
5. The high water vapor barrier rate and low resistance ITO membrane according to claim 1, characterized in that: The material of the second high-refractive-index inorganic oxide layer is niobium pentoxide, and the thickness of the second high-refractive-index inorganic oxide layer is 6-10 nm.
6. The high water vapor barrier rate and low resistance ITO membrane according to claim 1, characterized in that: The ITO layer has a thickness of 100-200 nm, and the dense hydrophobic layer is made of fluoroalkylsilane.
7. The high water vapor barrier rate and low resistance ITO membrane according to claim 1, characterized in that: The material of the substrate can be one of PET, PC or PI.
8. The high water vapor barrier rate and low resistance ITO membrane according to claim 1, characterized in that: The edge of the ITO layer is provided with a partition groove, and the ITO layer is provided with a dividing groove at intervals, which divides the ITO layer into several independent ITO blocks.
9. The high water vapor barrier rate and low resistance ITO membrane according to claim 8, characterized in that: An edge sealing layer is provided in the partition groove, and a conductive sealing layer is provided in the dividing groove, which connects the ITO blocks on both sides.
10. A method for preparing a high water vapor barrier and low resistance ITO membrane according to any one of claims 1-9, characterized in that, include: S1: Dry the substrate; S2: Apply an acrylic resin mixture evenly to one side of the substrate and bake at a low temperature of 60-80 degrees Celsius for 30 minutes. S3: Turn the substrate over, apply acrylic resin mixture evenly to the substrate again, and bake at a low temperature of 60-80 degrees Celsius for 30 minutes. S4: Silicon nitride, silicon dioxide, and niobium pentoxide are deposited sequentially using physical vapor deposition to form the first high-refractive-index inorganic oxide layer, the silicon dioxide layer, and the second high-refractive-index inorganic oxide layer. S5: The substrate temperature is controlled at 50-70°C, and indium tin oxide is deposited by magnetron sputtering in 5-8 stages to form the ITO layer; S6: Use a laser to etch the partition groove along the edge of the long side of the ITO layer, and use a laser to etch a plurality of the dividing grooves sequentially along the short side of the ITO layer; S7: Deposit metallic silver in the dividing groove using magnetron sputtering to form the conductive sealing layer; S8: A fluoroalkyl silane film is deposited in the partition groove using a vacuum evaporation method to form the edge sealing layer; S9: A second fluoroalkyl silane film is formed by vacuum evaporation on the ITO layer, the edge sealing layer and the conductive sealing layer to form the dense hydrophobic layer.