High-performance ITO conductive glass and preparation method thereof

Abstract

The application relates to the technical field of conductive glass preparation, in particular to high-performance ITO conductive glass and a preparation method thereof. The high-performance ITO conductive glass comprises, from top to bottom, a porous ITO film, an ITO film, an aluminum oxide film I, a glass substrate, an aluminum oxide film II, a niobium oxide film and a silicon dioxide film. The application innovatively prepares a porous ITO film on the surface of the ITO film, the porous structure in the porous ITO film can greatly reduce the scattering of light, and the light transmittance of the conductive glass is improved. Meanwhile, the porous ITO film has conductivity, and the carriers in the ITO film can be transmitted to the surface of the porous ITO film, so that the low square resistance of the ITO conductive glass is ensured, and the problem that the high light transmittance and the low square resistance of the ITO conductive glass cannot be simultaneously achieved is solved.

Description

Technical Field

[0001] This invention relates to the field of conductive glass preparation technology, specifically a high-performance ITO conductive glass and its preparation method. Background Technology

[0002] ITO conductive glass dominates in fields such as displays and touch screens, new energy and photovoltaics, smart windows, and energy-efficient buildings due to its excellent light transmittance and conductivity. However, the high light transmittance and low sheet resistance of the ITO film in ITO conductive glass are contradictory. Increasing the thickness of the ITO film or increasing the indium doping ratio to reduce its sheet resistance leads to a decrease in light transmittance. This is because charge carriers in the ITO film easily scatter photons, reducing visible light transmittance. Simply changing the ITO film thickness or doping process makes it difficult to simultaneously reduce the sheet resistance and increase the light transmittance of ITO conductive glass.

[0003] To address the aforementioned issues, a common technical solution involves preparing a low-refractive-index silica film on the surface of the ITO thin film in ITO conductive glass. While this silica film can improve light transmittance, and the increase in transmittance becomes more pronounced with increasing silica film thickness, the insulating properties of silica lead to a sharp increase in the sheet resistance of the ITO conductive glass. To avoid further deterioration of the sheet resistance, the silica film thickness is typically less than 30 nm, which significantly limits its effectiveness in improving the light transmittance of the ITO conductive glass. Therefore, there is an urgent need to develop an ITO conductive glass that combines low sheet resistance with high light transmittance. Summary of the Invention

[0004] To address the above technical problems, this invention provides a high-performance ITO conductive glass and its preparation method, so as to achieve both low sheet resistance and high light transmittance in the ITO conductive glass.

[0005] The present invention is specifically achieved through the following technical solution: a high-performance ITO conductive glass proposed according to the present invention, which consists of, from top to bottom: a porous ITO film, an ITO film, an alumina film I, a glass substrate, an alumina film II, a niobium oxide film, and a silicon dioxide film.

[0006] In the aforementioned high-performance ITO conductive glass, the thickness of the porous ITO film is 70~110 nm, the thickness of the ITO film is 70~140 nm, the thickness of alumina film I and alumina film II are both 90~110 nm, the thickness of the niobium oxide film is 10~15 nm, and the thickness of the silicon dioxide film is 90~110 nm.

[0007] The aforementioned high-performance ITO conductive glass has a sheet resistance of 8~22 Ω / sq and an average transmittance of 92~97% in the range of 380~780 nm.

[0008] This invention also provides a method for preparing high-performance ITO conductive glass, which specifically includes the following steps: S1. An alumina film II with a thickness of 90-110 nm, a niobium oxide film with a thickness of 10-15 nm, and a silicon dioxide film with a thickness of 90-110 nm are sequentially prepared on the reverse side of a glass substrate by magnetron sputtering. The alumina film II is located between the glass substrate and the niobium oxide film, and the niobium oxide film is located between the alumina film II and the silicon dioxide film. S2. Using magnetron sputtering, an alumina thin film I with a thickness of 90~110 nm and an ITO thin film with a thickness of 70~140 nm are sequentially prepared on the front side of the glass substrate obtained in step S1, wherein the alumina thin film I is located between the glass substrate and the ITO thin film. S3. An alumina-ITO composite film with a thickness of 70~100 nm is prepared on the surface of the ITO film on the glass substrate obtained in step S2 by magnetron sputtering. S4. Immerse the glass sample obtained in step S3 in an acidic solution for 30-60 minutes to completely remove the alumina in the alumina-ITO composite film. Then rinse the glass sample with deionized water and dry it at 60-100°C. The alumina-ITO composite film becomes a porous ITO film, completing the preparation of high-performance ITO conductive glass. The high-performance ITO conductive glass consists of the following components from top to bottom: porous ITO film, ITO film, alumina film I, glass substrate, alumina film II, niobium oxide film, and silicon dioxide film.

[0009] In the aforementioned method for preparing high-performance ITO conductive glass, in step S1, the target materials used to prepare alumina thin film II, niobium oxide thin film, and silicon dioxide thin film are aluminum target, niobium target, and silicon target, respectively. Magnetron sputtering is carried out in a mixed atmosphere of argon and oxygen. The specific process parameters are as follows: sputtering pressure 1 Pa, argon and oxygen flow rates 30 sccm and 1.3 sccm, respectively, and sputtering power 200 W.

[0010] In the aforementioned method for preparing high-performance ITO conductive glass, step S1 involves pre-treating the glass substrate before use. Specifically, the glass substrate is placed in acetone, anhydrous ethanol, and deionized water for ultrasonic treatment for 15-20 minutes each, and then dried at 60-100°C.

[0011] In the aforementioned method for preparing high-performance ITO conductive glass, in step S2, the target materials used to prepare alumina thin film I and ITO thin film are aluminum target and ITO target, respectively. Magnetron sputtering is carried out in a mixed atmosphere of argon and oxygen. The specific process parameters are as follows: sputtering pressure 1 Pa, argon and oxygen flow rates 30 sccm and 1.3 sccm, respectively, and sputtering power 200 W.

[0012] In the aforementioned method for preparing high-performance ITO conductive glass, step S3 involves co-sputtering an alumina-ITO composite film using an ITO target and an aluminum target. The magnetron sputtering is performed in a mixed atmosphere of argon and oxygen. The specific process parameters are: sputtering pressure of 1 Pa, argon and oxygen flow rates of 30 sccm and 1.3 sccm, respectively, ITO target sputtering power of 200 W, and the ratio of aluminum target sputtering power to ITO target sputtering power of 1:1 to 1:2.

[0013] In the aforementioned method for preparing high-performance ITO conductive glass, in step S4, the acidic solution is glacial acetic acid or a phosphoric acid solution with a mass percentage concentration of 85%.

[0014] The aforementioned method for preparing high-performance ITO conductive glass results in a sheet resistance of 8~22 Ω / sq and an average transmittance of 92~97% within the range of 380~780 nm.

[0015] In the aforementioned method for preparing high-performance ITO conductive glass, in step S4, after the glass sample is immersed entirely in an acidic solution, the alumina in the alumina-ITO composite film reacts with the acid in the solution and is thus removed. After rinsing with deionized water and drying, a porous structure is formed in the alumina-ITO composite film, making it a porous ITO film. On the one hand, the porous structure in the porous ITO film can greatly reduce light scattering, thus increasing light transmittance. On the other hand, the porous ITO film is conductive, allowing charge carriers in the ITO film to be transported to the surface of the porous ITO film, solving the problem that high light transmittance and low sheet resistance cannot be simultaneously achieved in conductive glass.

[0016] Compared with the prior art, the present invention has at least the following advantages: Existing technologies often involve preparing a low-refractive-index silica film on the surface of an ITO thin film to improve light transmittance. However, due to the insulating properties of silica, the thickness of the silica film is typically less than 30 nm to ensure low sheet resistance in the ITO conductive glass. This limits the range of transmittance adjustment, a phenomenon particularly pronounced when the ITO film thickness is large. This invention innovatively prepares a porous ITO film on the surface of the ITO thin film. The porous structure in the porous ITO film significantly reduces light scattering, thereby improving the transmittance of the ITO conductive glass. Simultaneously, the porous ITO film is conductive, allowing charge carriers in the ITO film to be transported to its surface, ensuring low sheet resistance and solving the problem of simultaneously achieving high transmittance and low sheet resistance in ITO conductive glass. Furthermore, this invention allows for adjustment of the refractive index by regulating the porosity of the porous ITO film. The porosity can be flexibly adjusted according to the thickness of the ITO film, thereby maximizing the transmittance of the ITO conductive glass. The porosity of porous ITO films can be adjusted by adjusting the sputtering power of the ITO target and the aluminum target, thereby adjusting the alumina content in the alumina-ITO composite film. After subsequent soaking in acidic solution, rinsing, and drying, porous ITO films with different porosities can be obtained.

[0017] The preparation method of this invention is simple, the raw materials are readily available, and the operation is convenient. The prepared high-performance ITO conductive glass has a sheet resistance as low as 8~22 Ω / sq and an average transmittance of 92~97% in the range of 380~780 nm. It can be widely used in information display, optoelectronic devices, smart car windows and other fields. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the high-performance ITO conductive glass prepared by the present invention.

[0019] Figure 2 This refers to the transmittance of the high-performance ITO conductive glass prepared in Example 1 within the range of 380~780 nm.

[0020] Figure 1 In the image, 1-porous ITO film, 2-ITO film, 3-alumina film I, 4-glass substrate, 5-alumina film II, 6-niobium oxide film, 7-silicon dioxide film. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, 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.

[0022] Unless otherwise specified, all conditions in the following examples were performed under conventional conditions or conditions recommended by the manufacturer. Raw materials and reagents without a specified manufacturer were all commercially available products. The aluminum, niobium, silicon, and ITO targets used in the examples and comparative examples were all commercially available products. The glass substrates used were identical on both sides; for ease of description, they are referred to as the "front side" and "back side," respectively.

[0023] Example 1 S1. An alumina film II with a thickness of 110 nm, a niobium oxide film with a thickness of 10 nm, and a silicon dioxide film with a thickness of 110 nm were sequentially prepared on the reverse side of a pretreated glass substrate using magnetron sputtering. The alumina film II was located between the glass substrate and the niobium oxide film, and the niobium oxide film was located between the alumina film II and the silicon dioxide film. The targets used for preparing the alumina film II, the niobium oxide film, and the silicon dioxide film were aluminum target, niobium target, and silicon target, respectively. The magnetron sputtering was carried out in a mixed atmosphere of argon and oxygen. The specific process parameters for preparing the alumina film II, the niobium oxide film, and the silicon dioxide film were as follows: sputtering pressure 1 Pa, argon flow rate 30 sccm, oxygen flow rate 1.3 sccm, and sputtering power 200 W. In this step, the glass substrate is pretreated before use. Specifically, the glass substrate is placed in acetone, anhydrous ethanol and deionized water for ultrasonic treatment for 15 min each, and then dried at 60°C. S2. Using magnetron sputtering, an alumina thin film I with a thickness of 110 nm and an ITO thin film with a thickness of 100 nm are sequentially prepared on the front side of the glass substrate obtained in step S1. The target materials used for preparing the alumina thin film I and the ITO thin film are aluminum target and ITO target, respectively. The magnetron sputtering is carried out in a mixed atmosphere of argon and oxygen. The specific process parameters for preparing the alumina thin film I and the ITO thin film are as follows: sputtering pressure 1 Pa, argon flow rate 30 sccm and oxygen flow rate 1.3 sccm, respectively, and sputtering power 200 W. S3. An alumina-ITO composite film with a thickness of 100 nm is prepared on the ITO film of the glass substrate obtained in step S2 by magnetron sputtering. The alumina-ITO composite film is obtained by co-sputtering with an ITO target and an aluminum target. The magnetron sputtering is carried out in a mixed atmosphere of argon and oxygen. The specific process parameters are: sputtering pressure 1 Pa, argon and oxygen flow rates 30 sccm and 1.3 sccm, respectively, and sputtering power of both the ITO target and the aluminum target 200 W. S4. Immerse the glass sample obtained in step S3 in a phosphoric acid solution with a mass percentage concentration of 85% for 30 minutes to completely remove the alumina in the alumina-ITO composite film. Then rinse the glass sample with deionized water and dry it at 60°C. The alumina-ITO composite film becomes a porous ITO film, and high-performance ITO conductive glass is obtained.

[0024] Figure 1 This is a schematic diagram of the structure of the high-performance ITO conductive glass prepared in this embodiment. The conductive glass consists of the following layers from top to bottom: porous ITO film 1, ITO film 2, alumina film I3, glass substrate 4, alumina film II5, niobium oxide film 6, and silicon dioxide film 7. The thicknesses of the porous ITO film 1, ITO film 2, alumina film I3, alumina film II5, niobium oxide film 6, and silicon dioxide film 7 are 100 nm, 100 nm, 110 nm, 110 nm, 10 nm, and 110 nm, respectively.

[0025] Figure 2 The curves showing the transmittance variation of the high-performance ITO conductive glass prepared in this embodiment within the range of 380~780 nm show that its average transmittance is 96.4%.

[0026] The sheet resistance of the high-performance ITO conductive glass prepared in this embodiment is 15.7 Ω / sq, according to the test results.

[0027] Example 2 S1. An alumina film II with a thickness of 100 nm, a niobium oxide film with a thickness of 15 nm, and a silicon dioxide film with a thickness of 100 nm were sequentially prepared on the reverse side of a pretreated glass substrate using magnetron sputtering. The alumina film II was located between the glass substrate and the niobium oxide film, and the niobium oxide film was located between the alumina film II and the silicon dioxide film. The targets used for preparing the alumina film II, the niobium oxide film, and the silicon dioxide film were aluminum target, niobium target, and silicon target, respectively. The magnetron sputtering was carried out in a mixed atmosphere of argon and oxygen. The specific process parameters for preparing the alumina film II, the niobium oxide film, and the silicon dioxide film were as follows: sputtering pressure 1 Pa, argon flow rate 30 sccm, oxygen flow rate 1.3 sccm, and sputtering power 200 W. In this step, the glass substrate is pretreated before use. Specifically, the glass substrate is placed in acetone, anhydrous ethanol and deionized water for ultrasonic treatment for 15 min each, and then dried at 80°C. S2. Using magnetron sputtering, an alumina thin film I with a thickness of 100 nm and an ITO thin film with a thickness of 140 nm are sequentially prepared on the front side of the glass substrate obtained in step S1. The target materials used for preparing the alumina thin film I and the ITO thin film are aluminum target and ITO target, respectively. The magnetron sputtering is carried out in a mixed atmosphere of argon and oxygen. The specific process parameters for preparing the alumina thin film I and the ITO thin film are as follows: sputtering pressure 1 Pa, argon flow rate 30 sccm and oxygen flow rate 1.3 sccm, respectively, and sputtering power 200 W. S3. An alumina-ITO composite film with a thickness of 110 nm is prepared on the ITO film of the glass substrate obtained in step S2 by magnetron sputtering. The alumina-ITO composite film is obtained by co-sputtering with an ITO target and an aluminum target. The magnetron sputtering is carried out in a mixed atmosphere of argon and oxygen. The specific process parameters are: sputtering pressure 1 Pa, argon and oxygen flow rates 30 sccm and 1.3 sccm, respectively, and sputtering power of both the ITO target and the aluminum target 200 W. S4. Immerse the glass sample obtained in step S3 in glacial acetic acid for 30 min to completely remove the alumina in the alumina-ITO composite film. Then rinse the glass sample with deionized water and dry it at 80°C. The alumina-ITO composite film becomes a porous ITO film, and high-performance ITO conductive glass is obtained.

[0028] Tests showed that the high-performance ITO conductive glass prepared in this embodiment has an average transmittance of 93.7% and a sheet resistance of 8.4 Ω / sq in the range of 380~780 nm.

[0029] Example 3 S1, the same as step S1 in Example 1; S2. Using magnetron sputtering, an alumina thin film I with a thickness of 100 nm and an ITO thin film with a thickness of 80 nm are sequentially prepared on the front side of the glass substrate obtained in step S1. The target materials used for preparing the alumina thin film I and the ITO thin film are aluminum target and ITO target, respectively. The magnetron sputtering is carried out in a mixed atmosphere of argon and oxygen. The specific process parameters for preparing the alumina thin film I and the ITO thin film are as follows: sputtering pressure 1 Pa, argon flow rate 30 sccm and oxygen flow rate 1.3 sccm, sputtering power 100 W. S3, the same as step S3 in Example 1; S4, the same as step S4 in Example 1.

[0030] Tests showed that the high-performance ITO conductive glass prepared in this embodiment had an average transmittance of 96.8% in the range of 380–780 nm and a sheet resistance of 21.6 Ω / sq.

[0031] Example 4 S1, the same as step S1 in Example 1; S2, the same as step S2 in Example 1; S3. An alumina-ITO composite film with a thickness of 70 nm is prepared on the ITO film of the glass substrate obtained in step S2 by magnetron sputtering. The alumina-ITO composite film is obtained by co-sputtering with an ITO target and an aluminum target. The magnetron sputtering is carried out in a mixed atmosphere of argon and oxygen. The specific process parameters are: sputtering pressure 1 Pa, argon and oxygen flow rates 30 sccm and 1.3 sccm, respectively, ITO target sputtering power 200 W, and aluminum target sputtering power 100 W. S4, the same as step S4 in Example 1.

[0032] Tests showed that the high-performance ITO conductive glass prepared in this embodiment had an average transmittance of 92.1% in the range of 380–780 nm and a sheet resistance of 13.2 Ω / sq.

[0033] Comparative Example 1 S1, the same as step S1 in Example 1; S2, the same as step S2 in Example 1, yields conductive glass D1.

[0034] Tests showed that the conductive glass D1 prepared in Comparative Example 1 had an average transmittance of 88.4% in the range of 380–780 nm and a sheet resistance of 16.2 Ω / sq.

[0035] Comparative Example 2 S1, the same as step S1 in Example 2; S2, the same as step S2 in Example 2, yields conductive glass D2.

[0036] Tests showed that the conductive glass D2 prepared in Comparative Example 2 had an average transmittance of 85.7% in the range of 380–780 nm and a sheet resistance of 9.7 Ω / sq.

[0037] Comparative Example 3 S1, the same as step S1 in Example 3; S2, the same as step S2 in Example 3, yields conductive glass D3.

[0038] Tests showed that the conductive glass D3 prepared in Comparative Example 3 had an average transmittance of 89.3% in the range of 380–780 nm and a sheet resistance of 22.7 Ω / sq.

[0039] Comparative Example 4 S1, the same as step S1 in Example 1; S2, the same as step S2 in Example 1; S3. A silicon dioxide thin film with a thickness of 35 nm is prepared on the ITO thin film of the glass substrate obtained in step S2 by magnetron sputtering. The target material used is a silicon target. The magnetron sputtering is carried out in a mixed atmosphere of argon and oxygen. The specific process is as follows: sputtering pressure 1 Pa, argon and oxygen flow rates 30 sccm and 1.3 sccm, respectively, silicon target sputtering power 200 W, to obtain conductive glass D4.

[0040] Tests showed that the conductive glass D4 prepared in Comparative Example 4 had an average transmittance of 90.5% in the range of 380–780 nm and a sheet resistance of 21.3 Ω / sq.

[0041] Comparative Example 5 S1, the same as step S1 in Example 1; S2, the same as step S2 in Example 1; S3. A silicon dioxide thin film with a thickness of 50 nm is prepared on the ITO thin film of the glass substrate obtained in step S2 by magnetron sputtering. The target material used is a silicon target. The magnetron sputtering is carried out in a mixed atmosphere of argon and oxygen. The specific process is as follows: sputtering pressure 1 Pa, argon and oxygen flow rates 30 sccm and 1.3 sccm, respectively, silicon target sputtering power 200 W, to obtain conductive glass D5.

[0042] Tests showed that the conductive glass D5 prepared in Comparative Example 5 had an average transmittance of 93.2% in the range of 380–780 nm and a sheet resistance of 2 kΩ / sq.

[0043] Table 1. Performance test data of conductive glasses obtained in Examples 1-4 and Comparative Examples 1-5 As shown in Table 1, compared to Comparative Example 1, preparing a layer of silica film on the surface of the ITO film (Comparative Examples 4-5) can effectively improve the light transmittance. Furthermore, the increase in transmittance is more pronounced with increasing silica film thickness. However, the insulating properties of silica lead to a sharp increase in the sheet resistance of the conductive glass. Compared to Comparative Examples 1-3, preparing a porous ITO film on the surface of the ITO film not only significantly improves the light transmittance of the ITO conductive glass but also maintains its good conductivity. The high-performance ITO conductive glass prepared by this invention maintains an average transmittance of 92-97% (within 380-780 nm) even with a sheet resistance of 8-22 Ω / sq, thus combining low sheet resistance and high transmittance, making it a high-performance ITO conductive glass.

[0044] The above description is merely an embodiment of the present invention and is not intended to limit the present invention in any way. The present invention can also have other embodiments based on the above structure and function, which will not be listed hereafter. Therefore, any simple modifications, equivalent changes, and alterations made by those skilled in the art to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for preparing high-performance ITO conductive glass, characterized in that, Includes the following steps: S1. Using magnetron sputtering, an aluminum oxide film II (5) with a thickness of 90~110 nm, a niobium oxide film (6) with a thickness of 10~15 nm, and a silicon dioxide film (7) with a thickness of 90~110 nm are sequentially prepared on the reverse side of a glass substrate (4). The aluminum oxide film II (5) is located between the glass substrate (4) and the niobium oxide film (6), and the niobium oxide film (6) is located between the aluminum oxide film II (5) and the silicon dioxide film (7). S2. Using magnetron sputtering, an aluminum oxide thin film I (3) with a thickness of 90~110 nm and an ITO thin film (2) with a thickness of 70~140 nm are sequentially prepared on the front side of the glass substrate (4) obtained in step S1. The aluminum oxide thin film I (3) is located between the glass substrate (4) and the ITO thin film (2). S3. An alumina-ITO composite film with a thickness of 70~100 nm is prepared on the surface of the ITO film (2) of the glass substrate (4) obtained in step S2 by magnetron sputtering. S4. Immerse the glass sample obtained in step S3 in an acidic solution for 30-60 min to completely remove the alumina in the alumina-ITO composite film. Then rinse the glass sample with deionized water and dry it at 60-100℃. The alumina-ITO composite film becomes a porous ITO film (1), completing the preparation of high-performance ITO conductive glass. The high-performance ITO conductive glass consists of the following components from top to bottom: porous ITO film (1), ITO film (2), alumina film I (3), glass substrate (4), alumina film II (5), niobium oxide film (6), and silicon dioxide film (7). The sheet resistance of the obtained high-performance ITO conductive glass is 8-22 Ω / sq, and the average transmittance in the range of 380-780 nm is 92-97%.

2. The method for preparing high-performance ITO conductive glass as described in claim 1, characterized in that, In step S1, the target materials used to prepare alumina thin film II (5), niobium oxide thin film (6), and silicon dioxide thin film (7) are aluminum target, niobium target, and silicon target, respectively. Magnetron sputtering is carried out in a mixed atmosphere of argon and oxygen. The specific process parameters are as follows: sputtering pressure 1 Pa, argon and oxygen flow rates 30 sccm and 1.3 sccm, respectively, and sputtering power 200 W.

3. The method for preparing high-performance ITO conductive glass as described in claim 1, characterized in that, In step S2, the target materials used to prepare alumina thin film I (3) and ITO thin film (2) are aluminum target and ITO target respectively. Magnetron sputtering is carried out in a mixed atmosphere of argon and oxygen. The specific process parameters are: sputtering pressure 1 Pa, argon and oxygen flow rates 30 sccm and 1.3 sccm respectively, and sputtering power 200 W.

4. The method for preparing high-performance ITO conductive glass as described in claim 1, characterized in that, In step S3, an alumina-ITO composite film is obtained by co-sputtering with an ITO target and an aluminum target. The magnetron sputtering is carried out in a mixed atmosphere of argon and oxygen. The specific process parameters are: sputtering pressure 1 Pa, argon and oxygen flow rates 30 sccm and 1.3 sccm, respectively, ITO target sputtering power 200 W, and the ratio of aluminum target sputtering power to ITO target sputtering power 1:1 to 1:

2.

5. The method for preparing high-performance ITO conductive glass as described in claim 1, characterized in that, In step S4, the acidic solution is glacial acetic acid or a phosphoric acid solution with a mass percentage concentration of 85%.

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