Barium-titanium-doped indium oxide target material and preparation method thereof

Abstract

The invention belongs to the field of target material preparation, and discloses a barium-titanium-doped indium oxide target material and a preparation method thereof. Comprising the following steps: mixing barium oxide powder, titanium oxide powder, indium oxide powder, a dispersing agent, a binder and deionized water, and then carrying out ball milling to obtain slurry I; the mass ratio of the barium oxide powder to the titanium oxide powder to the indium oxide powder is (10-20): (10-20): (60-80); drying, screening and calcining the slurry I to obtain powder I; mixing the powder I, titanium oxide powder, a dispersing agent, a binder and deionized water to obtain a mixture, carrying out ball milling to obtain slurry II, drying, and screening to obtain powder II; adding a binder into the powder material II, granulating, and screening to obtain powder material III; carrying out compression molding by taking the powder III as a raw material to obtain a target blank; and sequentially carrying out degreasing heat treatment, sintering heat treatment and cooling on the target blank to obtain the barium-titanium-doped indium oxide target material. The preparation method can be used for preparing the barium-titanium-doped indium oxide target material with uniform and compact crystal grains.

Description

Technical Field

[0001] The present invention belongs to the field of target material preparation, and more specifically, relates to a barium-doped titanium indium oxide target material and a preparation method thereof. Background Art

[0002] IBTO is a transparent oxide semiconductor material composed of In2O3, Ba2O3 and TiO in a certain proportion. Its special electronic structure makes it have similar photoelectric properties in both crystalline and non-crystalline states, and has the advantages of high electron mobility and large bandgap width.

[0003] Barium titanate is undoubtedly a representative of perovskite structure, which has a high dielectric constant and relatively low dielectric loss. Barium titanate was discovered more than 70 years ago and is the most widely used in the ferroelectric family. Its molecular formula is ABO3 type, A and B are metal elements, and O represents non-metal. The crystal structure of barium titanate, in which Ba 2+ At the top corner of the unit cell, Ti 4+ At the center of the unit cell, O 2- The barium titanate is located at the center of the six faces of the unit cell. The crystal structure of barium titanate determines that it is easy to form a solid solution with other oxides, so its dielectric properties are often improved by doping. Therefore, it is necessary to study the preparation of barium-doped titanium indium oxide targets.

[0004] CN116177993A discloses an indium oxide doped titanium tantalum cerium target and its preparation method. Indium oxide, titanium oxide, tantalum oxide and cerium oxide powders are weighed, added to pure water with a dispersant, stirred and dispersed evenly, and wet-ground to obtain slurry one; then indium oxide powder, dispersant and water are added and wet-ground to obtain slurry two; then a binder is added and mixed and wet-ground to obtain slurry three; spray granulation, mixing and screening are performed to obtain a mixed powder; finally, after molding and cold isostatic pressing, degreasing and sintering are performed to obtain an indium oxide doped titanium tantalum cerium target. This technical solution can significantly improve the various properties of the target by limiting the composition ratio of each oxide powder and coordinating a specific preparation process. However, this technical solution is not suitable for the preparation of barium-doped titanium indium oxide targets. Summary of the invention

[0005] In view of the above problems existing in the prior art, one of the objectives of the present invention is to provide a method for preparing a barium-doped titanium indium oxide target.

[0006] A second object of the present invention is to provide a barium-doped titanium indium oxide target.

[0007] To achieve the above purpose, the technical solution adopted by the present invention is: A method for preparing a barium-doped titanium indium oxide target comprises the following steps: (1) mixing barium oxide powder, titanium oxide powder, indium oxide powder, a dispersant, a binder, and deionized water, and then ball-milling to obtain slurry 1; wherein the mass ratio of the barium oxide powder, the titanium oxide powder, and the indium oxide powder is 10-20:10-20:60-80; (2) drying, screening and calcining the slurry 1 to obtain powder 1; (3) mixing powder material 1, titanium oxide powder, dispersant, binder and deionized water to obtain a mixture, ball milling to obtain slurry 2, drying and sieving to obtain powder material 2; (4) adding a binder to powder material 2 to perform granulation and sieving to obtain powder material 3; (5) Using powder material 3 as raw material for pressing and molding to obtain a target blank; (6) The target blank is subjected to degreasing heat treatment and sintering heat treatment in sequence, and after cooling, a barium-doped titanium indium oxide target is obtained.

[0008] Furthermore, the purity of the barium oxide powder is 4N; the purity of the titanium oxide powder is 4N; the purity of the indium oxide powder is 4N; Furthermore, the dispersant is one or more of polyvinyl pyrrolidone, sodium hexaalkylbenzene sulfonate, and polyacrylate; Furthermore, the binder is one or more of polyvinyl alcohol, polyethylene glycol, carboxymethyl cellulose, polyacrylamide, and polyacrylic acid salt.

[0009] Furthermore, in step (1), the amount of the dispersant added is 0.5-6.5% of the total mass of the added barium oxide, titanium oxide and indium oxide powders.

[0010] Furthermore, in step (1), the amount of the binder added is 1-9% of the total mass of the added barium oxide, titanium oxide and indium oxide powders.

[0011] Furthermore, in step (3), the amount of the dispersant added is 0.5-6.5% of the total mass of the added powder material 1 and titanium oxide powder.

[0012] Furthermore, in step (3), the amount of the binder added is 1-9% of the total mass of the added powder material 1 and titanium oxide powder.

[0013] Furthermore, in step (4), the amount of the binder added is 1-5% of the mass of the added powder.

[0014] Furthermore, the solid content of the slurry 1 is 60-70%.

[0015] Furthermore, the solid content of the slurry 2 is 60-70%.

[0016] Furthermore, in step (1), the ball milling speed is 15-30 Hz, and the ball milling time is 12-36 h.

[0017] Furthermore, in step (3), the ball milling speed is 15-30 Hz, and the ball milling time is 5-10 h.

[0018] Furthermore, in step (2), the calcination temperature is 1000-1250°C.

[0019] Furthermore, in the mixture obtained in step (3), the mass ratio of powder 1 to titanium oxide powder is 80-90%:10-20%.

[0020] Furthermore, the granulation process is crushing granulation or spray granulation.

[0021] Furthermore, the particle size of the particles after granulation is less than 53 um, and more preferably less than 26 um.

[0022] Furthermore, the mesh size of the sieve used for screening is 120 meshes.

[0023] Furthermore, step (5) of pressing and molding is as follows: pouring the powder material into a mold, performing uniaxial cold pressing, and performing cold isostatic pressing to obtain a target blank; Furthermore, the pressure during uniaxial cold pressing is 100~300Mpa, and the molding time is 100~200s; the pressure during cold isostatic pressing is 300~800Mpa, and the molding time is 60~200s.

[0024] Furthermore, in step (6), the degreasing heat treatment is: in an air atmosphere, heating to 500°C to 800°C at a heating rate of 0.1 to 0.5°C / min, and keeping the temperature for 3 to 10 hours; Furthermore, the sintering heat treatment is as follows: in an oxygen atmosphere, heating to 1000°C~1550°C at a heating rate of 0.5~5°C / min, and keeping the temperature for 2~6h.

[0025] The invention also discloses a barium-doped titanium indium oxide target material prepared by the preparation method of the barium-doped titanium indium oxide target material.

[0026] Compared with the prior art, the present invention has the following beneficial effects: This application successfully prepared a barium-doped titanium indium oxide target with uniform and dense grains by utilizing the additional sintering generated by the solid phase reaction during the sintering process. At the same time, low-temperature sintering is first performed in the sintering stage, so that the powder is easier to crystallize and grow during high-temperature sintering, thereby making the particle size distribution more uniform.

[0027] The present invention creatively adds additional titanium oxide powder, which can not only remove organic matter remaining on the surface of the powder, avoid pollution and residual additives, and ensure the dimensional accuracy and surface quality of the product, but also inhibit the growth of the IBT solid phase during the sintering process, effectively inhibit the abnormal growth of ceramic grains, form many small grains, thereby increasing the grain boundary area, and when the temperature rises to a certain level, titanium ions will migrate to the gaps and eventually form a single phase. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0029] In the attached picture: Figure 1 This is an electron microscope photograph of the barium-doped titanium indium oxide target obtained in Example 1; Figure 2 This is an electron microscope photograph of the barium-doped titanium indium oxide target obtained in Example 2; Figure 3 This is an electron microscope photograph of the barium-doped titanium indium oxide target obtained in Example 3; Figure 4 This is an electron microscope photograph of the barium-doped titanium indium oxide target obtained in Example 4; Figure 5 This is an electron microscope photograph of the barium-doped titanium indium oxide target obtained in Example 5; Figure 6 This is an electron microscope photograph of the barium-doped titanium indium oxide target obtained in Example 6; Figure 7 This is an electron microscope photograph of the barium-doped titanium indium oxide target obtained in Comparative Example 1; Figure 8 This is an electron microscope photograph of the barium-doped titanium indium oxide target obtained in Comparative Example 2; Fig. 9 This is an electron microscope photograph of the barium-doped titanium indium oxide target obtained in Comparative Example 3; Fig.10 This is an electron microscope photograph of the barium-doped titanium indium oxide target obtained in Comparative Example 4. DETAILED DESCRIPTION

[0030] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively and carefully in combination with preferred embodiments below, but the protection scope of the present invention is not limited to the following specific embodiments.

[0031] Unless otherwise defined, all the professional terms used below have the same meanings as those generally understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention.

[0032] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0033] Example 1 (1) Weigh barium oxide, titanium oxide and indium oxide powders in a mass ratio of 10%:10%:80%.

[0034] (2) Dissolve 5% of sodium hexaalkylbenzene sulfonate and 8% of polyvinyl alcohol in deionized water to obtain a solution 1.

[0035] (3) The barium oxide, titanium oxide and indium oxide powders weighed in step (1) and the solution 1 in step (2) were added to a ball mill for ball milling to obtain a slurry 1 with a solid content of 64%. The speed of the ball mill was 25 Hz and the ball milling time was 20 h.

[0036] (4) Drying, sieving and calcining the slurry 1 to obtain powder 1; wherein the calcination temperature is 1150° C.

[0037] (5) Add powder 1, titanium oxide powder, sodium hexaalkylbenzene sulfonate, polyvinyl alcohol, and deionized water into a ball mill, mix and grind in proportion to obtain slurry 2 with a solid content of 64%, and dry and sieve to obtain powder 2. The speed of the ball mill is 20 Hz, and the ball milling time is 6 hours. The mass ratio of powder 1 to titanium oxide powder is 80%:20%, the amount of sodium hexaalkylbenzene sulfonate added is 5% of the total mass of the added powder 1 and titanium oxide, and the amount of polyvinyl alcohol added is 8% of the total mass of the added powder 1 and titanium oxide.

[0038] (6) Powder 2 is added with polyvinyl alcohol for granulation and sieving to obtain powder 3, wherein the amount of polyvinyl alcohol added is 2% of the mass of powder 2 added, and the particle size of the particles after granulation is less than 53 μm. The mesh number of the sieve used during sieving is 120 mesh.

[0039] (7) Pour the powder into the mold and apply a certain uniaxial pressure to cold press and cold isostatic press to obtain a target blank. The pressure of the target material during cold pressing is 120 MPa and the molding time is 160 s; the pressure during cold isostatic pressing is between 400 MPa and the molding time is 120 s.

[0040] (8) The target blank is pre-sintered in a muffle furnace, and then the obtained preform is sintered in a sintering furnace to obtain an oxide target. The pre-sintering temperature is 600°C, the heating rate is 1.3°C / min, and the holding time is 4h; the sintering temperature is 1200°C, the heating rate is 1.3°C / min, the holding time is 5h, and the cooling rate is 1°C / min.

[0041] Example 2 This embodiment is basically the same as embodiment 1, except that the sintering temperature in step (8) is 1180°C.

[0042] Example 3 This embodiment is basically the same as embodiment 1, except that the sintering temperature in step (8) is 1220°C.

[0043] Example 4 This embodiment is basically the same as embodiment 1, except that in step (5), the mass ratio of powder 1 to TiO2 is 85%:15%. The amount of sodium hexaalkylbenzene sulfonate added is 5% of the total mass of the powder 1 and titanium oxide added, and the amount of polyvinyl alcohol added is 8% of the total mass of the powder 1 and titanium oxide added.

[0044] Example 5 This embodiment is basically the same as Embodiment 1, except that in step (5), the mass ratio of powder 1 to TiO2 is 90%:10%.

[0045] Example 6 This embodiment is basically the same as embodiment 1, except that the sintering holding time in step (8) is 5 hours.

[0046] Comparative Example 1 This comparative example is basically the same as Example 1, except that: In step (1), the mass ratio of barium oxide, titanium oxide and indium oxide powder is 10%:20%:70%; step (5) is not performed in this comparative example 1.

[0047] Specifically: (1) Weigh barium oxide, titanium oxide and indium oxide powders in a mass ratio of 10%:20%:70%.

[0048] (2) Dissolve 5% of sodium hexaalkylbenzene sulfonate and 8% of polyvinyl alcohol in deionized water to obtain a solution 1.

[0049] (3) The barium oxide, titanium oxide and indium oxide powders weighed in step (1) and the solution 1 in step (2) were added to a ball mill for ball milling to obtain a slurry 1 with a solid content of 64%. The speed of the ball mill was 25 Hz and the ball milling time was 20 h.

[0050] (4) Drying, sieving and calcining the slurry 1 to obtain powder 1. The calcination temperature is 1150°C.

[0051] (5) Add 2% by weight of polyvinyl alcohol to powder 1, granulate the mixture, and sieve the mixture to obtain powder 2.

[0052] (6) Pour the powder into the mold and apply a certain uniaxial pressure to cold press and cold isostatic press to obtain a target blank. The pressure of the target during cold pressing is 120Mpa and the molding time is 160s; the pressure during cold isostatic pressing is between 400Mpa and the molding time is 120s.

[0053] (7) The target blank is pre-sintered in a muffle furnace, and then the obtained preform is sintered in a sintering furnace to obtain an oxide target. The pre-sintering temperature is 600°C, the heating rate is 1.3°C / min, and the holding time is 4h; the sintering temperature is 1200°C, the heating rate is 1.3°C / min, the holding time is 5h, and the cooling rate is 1°C / min.

[0054] Comparative Example 2 This comparative example is basically the same as Example 1, except that in step (5), the mass ratio of powder 1 to TiO2 is 70%:30%.

[0055] Comparative Example 3 This comparative example is basically the same as Example 1, except that in step (8), the pre-burning holding time is 2 h.

[0056] Comparative Example 4 This comparative example is basically the same as Example 1, except that in step (5), the mass ratio of powder 1 to TiO2 is 95%:5%.

[0057] The relative density of the barium-doped titanium indium oxide targets obtained in Examples 1 to 6 and Comparative Examples 1 to 4 was tested by the Archimedean drainage method, and the test results are shown in Table 1. It can be seen that the barium-doped titanium indium oxide targets prepared in the present application have a relatively high relative density.

[0058] Table 1 The barium-doped titanium indium oxide targets obtained in Examples 1 to 6 and Comparative Examples 1 to 4 were subjected to SEM scanning electron microscopy. Figures 1 to 10 As shown. It can be seen that: The barium-doped titanium indium oxide target prepared in the present application has uniform grains. TiO2 can inhibit the growth of IBT solid phase during sintering, and can effectively inhibit the abnormal growth of ceramic grains to form many small grains, thereby increasing the grain boundary area. When the temperature is raised to a certain level, titanium ions will migrate to the gaps and eventually form a single phase.

[0059] In Comparative Example 1, since there is no additional titanium oxide for sintering, when the temperature is only 1200° C., the temperature required for grain growth cannot be reached.

[0060] In Comparative Example 2, since the titanium oxide content added in step (5) is too high, the titanium oxide grains occupy most of the positions when they grow, making it impossible for the IBT phase to grow further.

[0061] In Comparative Example 3, due to the short pre-sintering time, the residual dispersant and binder cannot be completely removed, and a large number of pores are formed during the sintering stage.

[0062] In Comparative Example 4, since the titanium oxide content added in step (5) is too low, the growth of the IBT phase cannot be effectively suppressed during the sintering stage, resulting in abnormal growth of the grains.

[0063] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of the present invention.

Claims

1. A method for preparing a barium-doped titanium indium oxide target, characterized in that: The following steps are involved: (1) mixing barium oxide powder, titanium oxide powder, indium oxide powder, a dispersant, a binder, and deionized water, and then ball-milling to obtain slurry 1; wherein the mass ratio of the barium oxide powder, the titanium oxide powder, and the indium oxide powder is 10-20:10-20:60-80; (2) drying, screening and calcining the slurry 1 to obtain powder 1; (3) mixing powder material 1, titanium oxide powder, dispersant, binder and deionized water to obtain a mixture, ball milling to obtain slurry 2, drying and sieving to obtain powder material 2; (4) adding a binder to powder material 2 to perform granulation and sieving to obtain powder material 3; (5) Using powder material 3 as raw material for pressing and molding to obtain a target blank; (6) The target blank is subjected to degreasing heat treatment and sintering heat treatment in sequence, and after cooling, a barium-doped titanium indium oxide target is obtained.

2. The preparation method according to claim 1, characterized in that The purity of the barium oxide powder is 4N; the purity of the titanium oxide powder is 4N; the purity of the indium oxide powder is 4N; Preferably, the dispersant is one or more of polyvinyl pyrrolidone, sodium hexaalkylbenzene sulfonate, and polyacrylate; Preferably, the binder is one or more of polyvinyl alcohol, polyethylene glycol, carboxymethyl cellulose, polyacrylamide, and polyacrylic acid salt; Preferably, in step (1), the amount of the dispersant added is 0.5-6.5% of the total mass of the added barium oxide, titanium oxide and indium oxide powders; Preferably, in step (1), the amount of the binder added is 1-9% of the total mass of the added barium oxide, titanium oxide and indium oxide powders; Preferably, in step (3), the amount of the dispersant added is 0.5-6.5% of the total mass of the added powder 1 and titanium oxide powder; Preferably, in step (3), the amount of the binder added is 1-9% of the total mass of the added powder 1 and titanium oxide powder; Preferably, in step (4), the amount of the binder added is 1-5% of the mass of the added powder.

3. The preparation method according to claim 1, characterized in that: The solid content of the slurry 1 is 60-70%; the solid content of the slurry 2 is 60-70%.

4. The preparation method according to claim 1, characterized in that: In step (1), the ball milling speed is 15-30 Hz, and the ball milling time is 12-36 h; in step (3), the ball milling speed is 15-30 Hz, and the ball milling time is 5-10 h.

5. The preparation method according to claim 1, characterized in that: In step (2), the calcination temperature is 1000-1250°C.

6. The preparation method according to claim 1, characterized in that: In the mixture obtained in step (3), the mass ratio of powder 1 to titanium oxide powder is 80-90%:10-20%.

7. The preparation method according to claim 1, characterized in that: The granulation process is crushing granulation or spray granulation; the particle size of the particles after granulation is less than 53um.

8. The preparation method according to claim 1, characterized in that: Step (5) of pressing and molding is as follows: pouring the powder into a mold, performing uniaxial cold pressing, and performing cold isostatic pressing to obtain a target blank; Preferably, the pressure during uniaxial cold pressing is 100-300 MPa, and the molding time is 100-200 s; the pressure during cold isostatic pressing is 300-800 MPa, and the molding time is 60-200 s.

9. The preparation method according to claim 1, characterized in that: In step (6), the degreasing heat treatment is as follows: in an air atmosphere, the temperature is raised to 500°C to 800°C at a heating rate of 0.1 to 0.5°C / min, and the temperature is kept for 3 to 10 hours; The sintering heat treatment is as follows: in an oxygen atmosphere, heating to 1000° C. to 1550° C. at a heating rate of 0.5 to 5° C. / min, and keeping the temperature for 2 to 6 hours.

10. The barium-doped titanium indium oxide target prepared by the preparation method according to any one of claims 1 to 9.

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