A highly uniform ITO target and its preparation method

Abstract

This application relates to the field of ITO target technology, and discloses a highly uniform ITO target and its preparation method. The highly uniform ITO target comprises the following raw materials in parts by weight: 96.5-99.5 parts of ITO powder and 0.5-3.5 parts of Cu / Ni nanocomposite; wherein the weight ratio of indium oxide to tin oxide in the ITO powder is 8.8-9.3:1. This application uses specific raw materials and proportions to prepare an ITO target with excellent comprehensive performance, effectively solving the problems of uneven internal microstructure and easy deformation, warping, and cracking during sintering of existing targets.

Description

Technical Field

[0001] This application relates to the field of ITO target technology, and in particular to a highly uniform ITO target and its preparation method. Background Technology

[0002] ITO targets, also known as indium tin oxide, are composed of indium oxide (In2O3) and tin oxide (SnO2), which are then pressed and sintered at high temperatures to form a dense ceramic target.

[0003] One important application of ITO targets is the formation of transparent conductive ITO thin films on substrates such as glass using vacuum magnetron sputtering. These films possess excellent optical and electrical properties, such as high visible light transmittance, high infrared reflectivity, and high ultraviolet light absorption. Furthermore, ITO films exhibit good conductivity, substrate adhesion, and chemical stability, making them widely used in various optoelectronic devices.

[0004] Specifically, ITO films are used as transparent conductive electrodes in flat panel displays (such as liquid crystal displays (LCDs) and organic light-emitting diodes (OLEDs) to drive pixels and conduct current. In touchscreen technology, ITO films are used to detect user touch operations. Furthermore, ITO films play an important role in fields such as solar cells, antistatic films, electromagnetic shielding films, and heat-reflective mirrors.

[0005] In traditional ITO targets, the addition of SnO2 as a sintering aid can lower the sintering temperature of the ITO target, but it will affect the light transmittance and electrical properties of the thin film. Furthermore, excessively high doping concentrations can cause grain boundary heat dissipation and the formation of non-conductive In4Sn3O. 12 Secondary phase; at the same time, the decrease in sintering temperature can easily lead to uneven microstructure inside the target material, and deformation, warping, cracking and other phenomena are likely to occur during the sintering process.

[0006] Therefore, there is an urgent need to provide an ITO sputtering material with good uniformity and that is not prone to cracking and deformation. Summary of the Invention

[0007] In order to solve at least one of the above-mentioned technical problems and to develop an ITO target material with good uniformity and that is not prone to cracking and deformation, this application provides a highly uniform ITO target material and its preparation method.

[0008] On the one hand, this application provides a highly uniform ITO target material comprising the following raw materials in parts by weight: 96.5-99.5 parts of ITO powder and 0.5-3.5 parts of Cu / Ni nanocomposite; wherein the weight ratio of indium oxide to tin oxide in the ITO powder is 8.8-9.3:1.

[0009] By adopting the above technical solution, this application uses specific raw materials and proportions to prepare ITO target materials with excellent comprehensive performance, which can effectively solve the problems of uneven internal microstructure of existing target materials and easy deformation, warping and cracking during sintering.

[0010] This application introduces Cu / Ni nanocomposite to optimize the arrangement of ITO particles, reduce voids and agglomeration, and help improve the uniformity of the microstructure inside the target material, thereby improving the overall performance of the target material. At the same time, the high specific surface area and activity of the nanocomposite can promote the connection between particles during sintering, thereby increasing the density and structural strength of the target material. In addition, the addition of nanocomposite can refine the grain structure of the target material, increase the number and strength of grain boundaries, thereby enhancing the target material's resistance to thermal and mechanical stress, and improving its crack resistance and deformation resistance.

[0011] Optionally, the raw materials include the following parts by weight: 97.5-98.3 parts of the ITO powder and 1.7-2.5 parts of the Cu / Ni nanocomposite.

[0012] By adopting the above technical solution, this application uses raw materials with a better ratio, which can adjust the sintering behavior of the target material to make it more uniform, thereby reducing the possibility of deformation and warping.

[0013] Optionally, the diameter of the Cu / Ni nanocomposite is 40-50 nm.

[0014] Optionally, the highly uniform ITO target material further includes zirconium oxide, wherein the zirconium oxide comprises 0.1-2.2 parts by weight.

[0015] By adopting the above technical solution, this application also adds zirconium oxide, which helps to form a more uniform structure in the ITO target material, reduce microscale inhomogeneity, and at the same time improve the stability of the ITO target material in high temperature environment.

[0016] Optionally, the average particle size of the zirconium oxide is not greater than 100 nm.

[0017] Optionally, the zirconium oxide is composed of zirconium oxide with an average particle size of 20-60 nm and zirconium oxide with an average particle size of 60-100 nm in a weight ratio of 0.2-0.5:0.5-0.8.

[0018] By adopting the above technical solution, this application uses zirconium oxide with a specific gradation, which can complement each other, reduce voids and defects, and facilitate the formation of a more uniform microstructure in the ITO target material; and help improve the dispersion and stability of zirconium oxide in the ITO target material, further enhancing the performance of the target material.

[0019] On the other hand, this application provides a method for preparing a highly uniform ITO target, comprising the following steps:

[0020] S1. Take ITO powder and Cu / Ni nanocomposite and mix them to prepare a mixture;

[0021] S2. Take pure water, additives, catalysts and dispersants, mix and stir, then add the mixture and continue mixing and stirring to prepare a slurry;

[0022] S3. After mixing and stirring the slurry with the binder, freeze-dry the mixture to prepare granules.

[0023] S4. The granular material is subjected to static pressing and sintering to obtain the highly uniform ITO target material.

[0024] In step S2, the weight ratio of the pure water, the additive, the catalyst, the dispersant, and the mixture is 75-92:0.1-0.3:0.1-0.3:1-4:100.

[0025] By adopting the above technical solution, the preparation method of the specific high-uniformity ITO target material in this application is simple to operate. At the same time, it enables the ITO powder and Cu / Ni nanocomposite to form a uniform mixture, thereby making the sintered particles tightly bonded and the target material has excellent uniformity.

[0026] Optionally, in S2, the additive is selected from one or both of boric acid and silicon dioxide; the catalyst is selected from ammonium dihydrogen phosphate; and the dispersant is selected from ammonium polyacrylate.

[0027] Preferably, the additive is boric acid and silicon dioxide in a weight ratio of 1:1.

[0028] Optionally, in step S3, the amount of adhesive added is 0.5-4% of the weight of the slurry.

[0029] Optionally, the adhesive is selected from polyvinyl alcohol solutions.

[0030] Optionally, the preparation method of the Cu / Ni nanocomposite includes the following steps:

[0031] 1) A double-channel porous alumina template was prepared by a two-stage anodic oxidation method. Then, a gold film with a thickness of 30nm-80nm was deposited on the back of the porous alumina template by magnetron sputtering, which served as the working electrode during electrodeposition.

[0032] 2) A mixed aqueous solution of nickel chloride, copper sulfate and lactic acid was used as the deposition electrolyte, and a carbon electrode was used as the auxiliary electrode. Electrodeposition was completed by a three-electrode pulse deposition method. Then, the template was removed by a 0.5 mol / L sodium hydroxide solution to obtain Cu / Ni nanocomposites with a diameter of 40-50 nm.

[0033] The preparation process of the deposition electrolyte is as follows: nickel chloride, copper sulfate, and boric acid in a mass ratio of 1:2:2 are added sequentially to 100 ml of pure water and stirred until homogeneous. The electrodeposition parameters are as follows: the deposition time of the Ni layer is 3 s to 7 s, and the deposition potential is -0.8 V to -1.3 V; the deposition time of the Cu layer is 10 s to 16 s, and the deposition potential is -0.3 V to -0.6 V.

[0034] In summary, the present invention has at least one of the following beneficial technical effects:

[0035] 1. This application uses specific raw materials and proportions to prepare ITO targets with high uniformity, which can effectively solve the problems of uneven internal microstructure of existing targets and the easy deformation, warping and cracking during sintering.

[0036] 2. By introducing Cu / Ni nanocomposite, this application can optimize the arrangement of ITO particles, reduce porosity and agglomeration, and help improve the uniformity of the microstructure inside the target material, thereby improving the overall performance of the target material. At the same time, the high specific surface area and activity of the nanocomposite can promote the connection between particles and the formation of necks during sintering, thereby increasing the density and structural strength of the target material. In addition, the addition of nanocomposite can refine the grain structure of the target material, increase the number and strength of grain boundaries, thereby enhancing the target material's resistance to thermal and mechanical stress, and enhancing its crack resistance and deformation resistance.

[0037] 3. The specific method for preparing highly uniform ITO target material used in this application is simple to operate. At the same time, it enables the ITO powder and Cu / Ni nanocomposite to form a uniform mixture, which in turn makes the sintered particles tightly bonded and the target material has excellent uniformity. Detailed Implementation

[0038] The present application will be further described in detail below with reference to the embodiments.

[0039] This application designs a highly uniform ITO target material, comprising the following raw materials in parts by weight: 96.5-99.5 parts of ITO powder and 0.5-3.5 parts of Cu / Ni nanocomposite; wherein, the weight ratio of indium oxide to tin oxide in the ITO powder is 8.8-9.3:1.

[0040] This application provides a method for preparing a highly uniform ITO target, comprising the following steps:

[0041] S1. Take ITO powder and Cu / Ni nanocomposite and mix them to prepare a mixture;

[0042] S2. Take pure water, additives, catalysts and dispersants, mix and stir, then add the mixture and continue mixing and stirring to prepare a slurry;

[0043] S3. After mixing and stirring the slurry with the binder, freeze-dry the mixture to prepare granules.

[0044] S4. The granular material is subjected to static pressing and sintering to obtain the highly uniform ITO target material.

[0045] In step S2, the weight ratio of the pure water, the additive, the catalyst, the dispersant, and the mixture is 75-92:0.1-0.3:0.1-0.3:1-4:100.

[0046] The raw materials used in this application are as follows. Unless otherwise specified, all raw materials used in this application are commercially available:

[0047] Zirconia: 99.9% purity;

[0048] Boric acid: 99% purity;

[0049] Silica: Yumu (Ningbo) New Materials Co., Ltd., Item No.: FEFG006, Purity 99.9%;

[0050] Ammonium dihydrogen phosphate: 99% purity;

[0051] Ammonium polyacrylate: 99% purity;

[0052] Polyvinyl alcohol: 99.99% purity;

[0053] Pure water: CAS No. 9002-88-4;

[0054] Nickel chloride: 99% purity;

[0055] Copper sulfate: 99% purity;

[0056] Lactic acid: 99% purity.

[0057] Testing items and methods:

[0058] Relative density (%): The relative density of the prepared ITO target was tested using the Archimedes displacement method;

[0059] Mobility (cm) 2 / (V*s)): On a cleaned glass substrate, the prepared ITO target material is sputtered to deposit a TCO thin film. The deposition power is 150W, the sputtering gas is Ar, the deposition atmosphere is H2 / O2 mixed gas, the film thickness is 80mm, and the mobility of the film is tested using a Hall effect tester.

[0060] Examples 1-3

[0061] Example 1

[0062] A method for preparing a highly uniform ITO target includes the following steps:

[0063] S1, Take 96.5g of material with a specific surface area of ​​12m². 2 The ITO powder prepared by the co-precipitation reaction of / g and 3.5g of Cu / Ni nanocomposite were mixed and stirred to prepare a mixture; wherein, the weight ratio of indium oxide to tin oxide in the ITO powder was 9.3:1.

[0064] S2. Take pure water, additives, catalysts and dispersants, mix and stir, then add the mixture and continue mixing and stirring to prepare a slurry;

[0065] S3. After mixing and stirring the slurry with the binder, freeze-dry the mixture to prepare granules.

[0066] S4. The granular material is subjected to static pressing and sintering to obtain the highly uniform ITO target material.

[0067] In step S2, the weight ratio of the pure water, the additive, the catalyst, the dispersant, and the mixture is 75:0.3:0.1:1:100.

[0068] In S2, the additive is selected from silicon dioxide; the catalyst is selected from ammonium dihydrogen phosphate; and the dispersant is selected from ammonium polyacrylate.

[0069] In step S3, the amount of adhesive added is 0.5% of the weight of the slurry; the adhesive is selected from a polyvinyl alcohol solution, and the concentration of the polyvinyl alcohol is 30 wt%.

[0070] Example 2

[0071] A method for preparing a highly uniform ITO target includes the following steps:

[0072] S1, take 97.5g of material with a specific surface area of ​​12m². 2 The ITO powder prepared by the co-precipitation reaction of / g and 2.5g of Cu / Ni nanocomposite were mixed and stirred to prepare a mixture; wherein, the weight ratio of indium oxide to tin oxide in the ITO powder was 9.1:1.

[0073] S2. Take pure water, additives, catalysts and dispersants, mix and stir, then add the mixture and continue mixing and stirring to prepare a slurry;

[0074] S3. After mixing and stirring the slurry with the binder, freeze-dry the mixture to prepare granules.

[0075] S4. The granular material is subjected to static pressing and sintering to obtain the highly uniform ITO target material.

[0076] In step S2, the weight ratio of the pure water, the additive, the catalyst, the dispersant, and the mixture is 84:0.2:0.2:3:100.

[0077] In S2, the additive is selected from silicon dioxide; the catalyst is selected from ammonium dihydrogen phosphate; and the dispersant is selected from ammonium polyacrylate.

[0078] In step S3, the amount of adhesive added is 2.8% of the weight of the slurry; the adhesive is selected from a polyvinyl alcohol solution, and the concentration of the polyvinyl alcohol is 30 wt%.

[0079] Example 3

[0080] A method for preparing a highly uniform ITO target includes the following steps:

[0081] S1. Take 99.5g of material with a specific surface area of ​​12m². 2 The ITO powder prepared by the co-precipitation reaction of / g and 0.5g of Cu / Ni nanocomposite were mixed and stirred to prepare a mixture; wherein the weight ratio of indium oxide to tin oxide in the ITO powder was 8.8:1.

[0082] S2. Take pure water, additives, catalysts and dispersants, mix and stir, then add the mixture and continue mixing and stirring to prepare a slurry;

[0083] S3. After mixing and stirring the slurry with the binder, freeze-dry the mixture to prepare granules.

[0084] S4. The granular material is subjected to static pressing and sintering to obtain the highly uniform ITO target material.

[0085] In step S2, the weight ratio of the pure water, the additive, the catalyst, the dispersant, and the mixture is 92:0.1:0.3:4:100.

[0086] In S2, the additive is selected from silicon dioxide; the catalyst is selected from ammonium dihydrogen phosphate; and the dispersant is selected from ammonium polyacrylate.

[0087] In step S3, the amount of adhesive added is 4% of the weight of the slurry; the adhesive is selected from a polyvinyl alcohol solution, and the concentration of the polyvinyl alcohol is 30 wt%.

[0088] The preparation methods of the Cu / Ni nanocomposites in Examples 1-3 are consistent.

[0089] Specifically, the preparation method of Cu / Ni nanocomposites includes the following steps:

[0090] 1) A double-channel porous alumina template was prepared by a two-stage anodic oxidation method. Then, a gold film with a thickness of 40 nm was deposited on the back of the porous alumina template by magnetron sputtering, which served as the working electrode during electrodeposition.

[0091] 2) A mixed aqueous solution of nickel chloride, copper sulfate and lactic acid was used as the deposition electrolyte, and a carbon electrode was used as the auxiliary electrode. Electrodeposition was completed by a three-electrode pulse deposition method. Then, the template was removed by a 0.5 mol / L sodium hydroxide solution to obtain Cu / Ni nanocomposites with a diameter of 40-50 nm.

[0092] 3) Preparation of deposition electrolyte: Add nickel chloride, copper sulfate and boric acid in a mass ratio of 1:2:2 to 100ml of pure water and stir until homogeneous; The electrodeposition parameters are: Ni layer deposition time is 5s and deposition potential is -0.8v; Cu layer deposition time is 12s and deposition potential is -0.4v.

[0093] Examples 4-5

[0094] Based on Example 2, except for the different weights of ITO powder and Cu / Ni nanocomposite, the other components and preparation methods are the same as in Example 2.

[0095] Example 4

[0096] 98g of ITO powder and 2g of Cu / Ni nanocomposite.

[0097] Example 5

[0098] 98.3g of ITO powder and 1.7g of Cu / Ni nanocomposite.

[0099] Comparative Example 1

[0100] Based on Example 2, except that an equal amount of ITO powder was used to replace the Cu / Ni nanocomposite, the other components and preparation methods were the same as in Example 2.

[0101] Comparative Example 2

[0102] Based on Example 2, except for 95g of ITO powder and 5g of Cu / Ni nanocomposite, the other components and preparation methods are the same as in Example 2.

[0103] Comparative Example 3

[0104] Based on Example 2, except for 99.8g of ITO powder and 0.2g of Cu / Ni nanocomposite, the other components and preparation methods are the same as in Example 2.

[0105] The performance of the ITO targets prepared in Examples 1-5 and Comparative Examples 1-2 was tested, and the test results are shown in Table 1.

[0106] Table 1

[0107]

[0108]

[0109] As can be seen from Examples 1-3, Comparative Examples 1-3 and Table 1, the ITO target material prepared by this application using specific raw materials and proportions has excellent comprehensive performance and can effectively solve the problems of uneven internal microstructure of existing target materials and easy deformation, warping and cracking during sintering.

[0110] By introducing Cu / Ni nanocomposites, their uniform distribution within ITO powder can act as a "filler" to optimize the arrangement of ITO particles, reduce voids and agglomeration, and improve the uniformity of the microstructure within the target material, thereby enhancing its overall performance. Simultaneously, the high specific surface area and activity of the nanocomposites can promote particle-to-particle bonding and neck formation during sintering, increasing the density and structural strength of the target material. Furthermore, the addition of nanocomposites can refine the grain structure of the target material, increasing the number and strength of grain boundaries, thus enhancing the target material's resistance to thermal and mechanical stresses and improving its crack and deformation resistance.

[0111] As can be seen from Examples 2, 4-5 and Table 1, the ITO target material prepared by using raw materials with a better ratio in this application has better uniformity and higher migration rate after coating.

[0112] Examples 6-9

[0113] Based on Example 4, except that the high-uniformity ITO target material also includes zirconium oxide, the other components and preparation methods are the same as in Example 4.

[0114] Example 6

[0115] The zirconium oxide has a weight fraction of 0.1g and an average particle size of 100nm.

[0116] Example 7

[0117] The zirconium oxide has a weight of 1.2g and an average particle size of 100nm.

[0118] Example 8

[0119] The zirconium oxide has a weight of 2.2g and an average particle size of 100nm.

[0120] Examples 9-11

[0121] Based on Example 7, except for the average particle size of zirconium oxide, the other components and preparation methods are the same as in Example 7.

[0122] Example 9

[0123] Zirconia is composed of zirconia with an average particle size of 60 nm and zirconia with an average particle size of 100 nm in a weight ratio of 0.2:0.8.

[0124] Example 10

[0125] Zirconia is composed of zirconia with an average particle size of 40 nm and zirconia with an average particle size of 80 nm in a weight ratio of 0.3:0.7.

[0126] Example 11

[0127] Zirconia is composed of zirconia with an average particle size of 20 nm and zirconia with an average particle size of 60 nm in a weight ratio of 0.5:0.5.

[0128] Examples 12-13

[0129] Based on Example 10, except for the different types of additives, the other components and preparation methods are the same as in Example 10.

[0130] Example 12

[0131] The additive is boric acid.

[0132] Example 13

[0133] The additives are boric acid and silicon dioxide in a weight ratio of 1:1.

[0134] The ITO targets prepared in Examples 6-13 were subjected to performance testing, and the test results are shown in Table 2.

[0135] Table 2

[0136]

[0137] As can be seen from Examples 6-8, 4 and Table 2, this application also adds zirconium oxide, which helps to form a more uniform structure in the ITO target material, reduce microscale inhomogeneity, and at the same time, can improve the stability of the ITO target material in high temperature environment.

[0138] As can be seen from Examples 9-11, 7 and Table 2, the zirconium oxide with a specific gradation used in this application can complement each other, reduce voids and defects, and facilitate the formation of a more uniform microstructure in the ITO target material; and help improve the dispersion and stability of zirconium oxide in the ITO target material, further enhancing the performance of the target material.

[0139] As can be seen from Examples 12-13, 10 and Table 2, this application uses boric acid and silica in a specific ratio as additives, which effectively promotes the dispersion uniformity of the slurry and increases the density of the target material, thereby improving the uniformity of the target material.

[0140] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the principles of this application should be covered within the scope of protection of this application.

Claims

1. A highly uniform ITO sputtering target, characterized in that, The raw materials include the following parts by weight: 96.5-99.5 parts of ITO powder and 0.5-3.5 parts of Cu / Ni nanocomposite; wherein the weight ratio of indium oxide to tin oxide in the ITO powder is 8.8-9.3:1; the high-uniformity ITO target also includes zirconium oxide, wherein the zirconium oxide is in the amount of 0.1-2.2 parts by weight and the average particle size of the zirconium oxide is not greater than 100 nm.

2. The highly uniform ITO target material according to claim 1, characterized in that, The raw materials include the following parts by weight: 97.5-98.3 parts of ITO powder and 1.7-2.5 parts of Cu / Ni nanocomposite.

3. The highly uniform ITO target material according to claim 1, characterized in that, The diameter of the Cu / Ni nanocomposite is 40-50 nm.

4. The highly uniform ITO target material according to claim 1, characterized in that, The zirconium oxide is composed of zirconium oxide with an average particle size of 20-60 nm and zirconium oxide with an average particle size of 60-100 nm in a weight ratio of 0.2-0.5:0.5-0.

8.

5. A method for preparing a highly uniform ITO target material according to any one of claims 1-4, characterized in that, Includes the following steps: S1. Take ITO powder and Cu / Ni nanocomposite and mix them to prepare a mixture; S2. Take pure water, additives, catalysts and dispersants, mix and stir, then add the mixture and continue mixing and stirring to prepare a slurry; S3. After mixing and stirring the slurry with the binder, freeze-dry the mixture to prepare granules. S4. The granular material is subjected to static pressing and sintering to obtain the highly uniform ITO target material. In step S2, the weight ratio of the pure water, the additive, the catalyst, the dispersant, and the mixture is 75-92: 0.1-0.3:0.1-0.3:1-4:100。 6. The method for preparing a highly uniform ITO target according to claim 5, characterized in that, In S2, the additive is selected from one or both of boric acid and silicon dioxide; the catalyst is selected from ammonium dihydrogen phosphate; and the dispersant is selected from ammonium polyacrylate.

7. The method for preparing a highly uniform ITO target according to claim 5, characterized in that, In step S3, the amount of adhesive added is 0.5-4% of the weight of the slurry.

8. The method for preparing a highly uniform ITO target according to claim 7, characterized in that, The adhesive is selected from polyvinyl alcohol solution.

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