A barium-doped indium titanium oxide target and a method for manufacturing the same

Abstract

The application belongs to the field of target material preparation and discloses a barium-doped indium titanium oxide target material and a preparation method thereof. The method comprises the following steps: mixing barium oxide powder, titanium oxide powder, indium oxide powder, a dispersing agent, a binder and deionized water, and ball milling to obtain slurry one; the mass ratio of the barium oxide powder, the titanium oxide powder and the indium oxide powder is 10-20:10-20:60-80; drying, screening and calcining the slurry one to obtain powder one; mixing the powder one, titanium oxide powder, a dispersing agent, a binder and deionized water to obtain a mixture, ball milling to obtain slurry two, drying and screening to obtain powder two; adding a binder to the powder two to granulate and screen to obtain powder three; using the powder three as raw material to perform compression molding to obtain a target blank; and performing, in sequence, a debinding heat treatment, a sintering heat treatment and cooling to obtain the barium-doped indium titanium oxide target material. The application can prepare a barium-doped indium titanium oxide target material with uniform and dense crystal grains.

Description

Technical Field

[0001] This invention belongs to the field of target preparation, and more specifically, relates to a barium-doped titanium indium oxide target and its preparation method. Background Technology

[0002] IBTO is a transparent oxide semiconductor material composed of In2O3, Ba2O3 and TiO in a certain proportion. Its special electronic structure gives it similar photoelectric properties in both crystalline and amorphous states, and it also has advantages such as high electron mobility and a large band gap.

[0003] Barium titanate is undoubtedly the representative of the perovskite structure, possessing a high dielectric constant and relatively low dielectric loss. Discovered over seventy years ago, barium titanate is the most widely used member of the ferroelectric family. Its molecular formula is ABO3, where A and B are metallic elements and O represents a nonmetal. The crystal structure of barium titanate includes Ba... 2+ Located at the apex of the unit cell, Ti 4+ Located at the center of the unit cell, O 2- It is located at the face centers of the six faces of the unit cell. The crystal structure of barium titanate makes it prone to forming solid solutions with other oxides, so its dielectric properties are often improved through doping. Therefore, it is necessary to study the preparation of barium-doped indium titanate 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 and added to pure water with a dispersant. The mixture is stirred and dispersed evenly, then wet-milled to obtain slurry one. Indium oxide powder, dispersant, and water are then added, and the mixture is wet-milled again to obtain slurry two. A binder is then added, and the mixture is wet-milled again to obtain slurry three. The mixture is then spray-granulated, mixed, and sieved to obtain a mixed powder. Finally, after molding and cold isostatic pressing, the powder is degreased and sintered to obtain the indium oxide-doped titanium-tantalum-cerium target. This technical solution, by limiting the composition ratio of each oxide powder and combining it with a specific preparation process, can significantly improve the various properties of the target material. However, this technical solution is not applicable to the preparation of barium-doped titanium indium oxide targets. Summary of the Invention

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

[0006] The second objective of this invention is to provide a barium-doped titanium indium oxide target.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A method for preparing a barium-doped indium titanium oxide target includes the following steps: (1) Barium oxide powder, titanium oxide powder, indium oxide powder, dispersant, binder and deionized water are mixed and ball-milled to obtain slurry one; wherein the mass ratio of barium oxide powder, titanium oxide powder and indium oxide powder is 10~20:10~20:60~80; (2) Dry, sieve and calcine the slurry to obtain powder. (3) Mix powder one, titanium dioxide powder, dispersant, binder and deionized water to obtain a mixture, ball mill to obtain slurry two, dry and sieve to obtain powder two; (4) Add a binder to powder two for granulation and sieving to obtain powder three; (5) Using powder three as raw material, the target blank is pressed and formed. (6) The target blank is subjected to degreasing heat treatment and sintering heat treatment in sequence, and then cooled to obtain barium-doped titanium indium oxide target material.

[0008] Furthermore, the purity of the barium oxide powder is 4N; the purity of the titanium oxide powder is 4N; and the purity of the indium oxide powder is 4N. Further, the dispersant is one or more of polyvinylpyrrolidone, sodium hexaalkylbenzenesulfonate, and polyvinyl salt; Furthermore, the adhesive is one or more of polyvinyl alcohol, polyethylene glycol, carboxymethyl cellulose, polyacrylamide, and polyacrylate.

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

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

[0011] Further, in step (3), the amount of dispersant added is 0.5 to 6.5% of the total mass of the added powder and titanium dioxide powder.

[0012] Further, in step (3), the amount of binder added is 1 to 9% of the total mass of the added powder and titanium dioxide powder.

[0013] Further, in step (4), the amount of adhesive added is 1 to 5% of the mass of the added powder.

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

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

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

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

[0018] Furthermore, in step (2), the calcination temperature is 1000~1250℃.

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

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

[0021] Furthermore, the particle size of the granulated particles is less than 53 μm, and more preferably less than 26 μm.

[0022] Furthermore, the sieve used for screening has a mesh size of 120.

[0023] Further, step (5) pressing and molding is as follows: the powder is poured into the mold and subjected to uniaxial pressure cold pressing and cold isostatic pressing to obtain the target blank; Furthermore, the pressure during uniaxial pressure 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.

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

[0025] The present invention also discloses the barium-doped indium titanium oxide target prepared by the above-mentioned method.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows: This application utilizes the additional sintering effect generated by the solid-state reaction during sintering to successfully prepare barium-doped indium titanium oxide (ITO) targets with uniform and dense grains. Simultaneously, low-temperature sintering is performed first during the sintering stage, making it easier for the powder to crystallize and grow during high-temperature sintering, resulting in a more uniform particle size distribution.

[0027] This invention creatively adds titanium dioxide powder, which not only removes residual organic matter on the powder surface, avoiding contamination and additive residue, and ensuring the dimensional accuracy and surface quality of the product, but also inhibits the growth of the IBT solid phase during sintering. This effectively suppresses abnormal growth of ceramic grains, forming many small grains, thereby increasing the grain boundary area. When the temperature is raised to a certain level, titanium ions migrate into the voids and eventually form a single phase. Attached Figure Description

[0028] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0029] In the attached diagram: Figure 1 Electron micrograph of the barium-doped indium titanium oxide target obtained in Example 1; Figure 2 Electron micrograph of the barium-doped indium titanium oxide target obtained in Example 2; Figure 3 Electron micrograph of the barium-doped indium titanium oxide target obtained in Example 3; Figure 4 Electron micrograph of the barium-doped indium titanium oxide target obtained in Example 4; Figure 5 Electron micrograph of the barium-doped indium titanium oxide target obtained in Example 5; Figure 6 Electron micrograph of the barium-doped indium titanium oxide target obtained in Example 6; Figure 7 Electron micrograph of the barium-doped indium titanium oxide target obtained in Comparative Example 1; Figure 8 Electron micrograph of the barium-doped indium titanium oxide target obtained in Comparative Example 2; Figure 9 Electron micrograph of the barium-doped indium titanium oxide target obtained in Comparative Example 3; Figure 10 This is an electron microscope image of the barium-doped titanium indium oxide target obtained in Comparative Example 4. Detailed Implementation

[0030] To facilitate understanding of the present invention, the present invention will be described more fully and in detail below with reference to preferred embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.

[0031] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

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

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

[0034] (2) Dissolve sodium hexaalkylbenzenesulfonate (5% by mass of barium oxide, titanium oxide and indium oxide powder) and polyvinyl alcohol (8% by mass) in deionized water until fully dissolved to obtain solution one.

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

[0036] (4) The slurry is dried, sieved and calcined to obtain powder; wherein the calcination temperature is 1150℃.

[0037] (5) Add powder one, titanium dioxide powder, sodium hexaalkylbenzenesulfonate, polyvinyl alcohol, and deionized water to a ball mill and mix them in proportion to obtain slurry two with a solid content of 64%. Dry and sieve to obtain powder two. The ball mill speed is 20 Hz and the ball milling time is 6 h. The mass ratio of powder one to titanium dioxide powder is 80%:20%. The amount of sodium hexaalkylbenzenesulfonate added is 5% of the total mass of powder one and titanium dioxide, and the amount of polyvinyl alcohol added is 8% of the total mass of powder one and titanium dioxide.

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

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

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

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

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

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

[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%; in this comparative example 1, step (5) is not performed.

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

[0048] (2) Dissolve sodium hexaalkylbenzenesulfonate (5% by mass of barium oxide, titanium oxide and indium oxide powder) and polyvinyl alcohol (8% by mass) in deionized water until fully dissolved to obtain solution one.

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

[0050] (4) The slurry is dried, sieved and calcined to obtain powder. The calcination temperature is 1150℃.

[0051] (5) Add 2% polyvinyl alcohol by total mass to powder one and granulate and sieve to obtain powder two.

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

[0053] (7) The target blank is pre-fired in a muffle furnace, and then the obtained preform is sintered in a sintering furnace to obtain an oxide target material. The pre-fired temperature is 600℃, the heating rate is 1.3℃ / min, and the holding time is 4h; the sintering temperature is 1200℃, the heating rate is 1.3℃ / min, the holding time is 5h, and the cooling rate is 1℃ / 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 heat preservation time for preheating is 2 hours.

[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 densities of the barium-doped indium titanium oxide targets obtained in Examples 1-6 and Comparative Examples 1-4 were tested using the Archimedes displacement method, and the results are shown in Table 1. It can be seen that the barium-doped indium titanium oxide targets prepared in this application possess a high relative density.

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

[0059] Comparative Example 1, due to the lack of additional titanium dioxide for sintering, could not reach the temperature required for grain growth at only 1200℃.

[0060] In Comparative Example 2, due to the excessive addition of titanium dioxide in step (5), the titanium dioxide grains occupied most of the positions during growth, preventing the IBT phase from undergoing further grain growth.

[0061] Comparative Example 3, due to its short pre-sintering time, could not completely remove the residual dispersant and binder, resulting in a large number of pores during the sintering stage.

[0062] In Comparative Example 4, the titanium dioxide content added in step (5) was too low, which could not effectively suppress the growth of the IBT phase during the sintering stage, resulting in abnormal grain growth.

[0063] The above are merely preferred embodiments of the present invention and are not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of the present invention.

Claims

1. A method for preparing a barium-doped indium titanium oxide target, characterized in that, Includes the following steps: (1) Barium oxide powder, titanium oxide powder, indium oxide powder, dispersant, binder and deionized water are mixed and ball-milled to obtain slurry one; wherein the mass ratio of barium oxide powder, titanium oxide powder and indium oxide powder is 10~20:10~20:60~80; (2) Dry, sieve and calcine the slurry to obtain powder. (3) Mix powder one, titanium dioxide powder, dispersant, binder and deionized water to obtain a mixture, ball mill to obtain slurry two, dry and sieve to obtain powder two; in the obtained mixture, the mass ratio of powder one to titanium dioxide powder is 80~90%:10~20%; (4) Add a binder to powder two for granulation and sieving to obtain powder three; (5) Using powder three as raw material, the target blank is pressed and formed. (6) The target blank is subjected to degreasing heat treatment and sintering heat treatment in sequence, and then cooled to obtain barium titanium indium oxide target material; the degreasing heat treatment is: air atmosphere, heating to 500℃~800℃ at a heating rate of 0.1~0.5℃ / min, and holding for 3~10h; the sintering heat treatment is: oxygen atmosphere, heating to 1000℃~1550℃ at a heating rate of 0.5~5℃ / min, and holding for 2~6h.

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.

3. The preparation method according to claim 1, characterized in that, The dispersant is one or more of polyvinylpyrrolidone, sodium hexaalkylbenzenesulfonate, and polyvinyl salt.

4. The preparation method according to claim 1, characterized in that, The adhesive is one or more of polyvinyl alcohol, polyethylene glycol, carboxymethyl cellulose, polyacrylamide, and polyacrylate.

5. The preparation method according to claim 1, characterized in that, In step (1), the amount of dispersant added is 0.5 to 6.5% of the total mass of the added barium oxide, titanium oxide and indium oxide powders.

6. The preparation method according to claim 1, characterized in that, In step (1), the amount of binder added is 1 to 9% of the total mass of the added barium oxide, titanium oxide and indium oxide powders.

7. The preparation method according to claim 1, characterized in that, In step (3), the amount of dispersant added is 0.5 to 6.5% of the total mass of the added powder and titanium dioxide powder.

8. The preparation method according to claim 1, characterized in that, In step (3), the amount of binder added is 1 to 9% of the total mass of the added powder and titanium dioxide powder.

9. The preparation method according to claim 1, characterized in that, In step (4), the amount of adhesive added is 1 to 5% of the mass of the added powder.

10. The preparation method according to claim 1, characterized in that, The solid content of slurry one is 60-70%; the solid content of slurry two is 60-70%.

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

12. The preparation method according to claim 1, characterized in that, In step (2), the calcination temperature is 1000~1250℃.

13. The preparation method according to claim 1, characterized in that, The granulation process is either crushing granulation or spray granulation; the particle size of the granulated particles is less than 53 μm.

14. The preparation method according to claim 1, characterized in that, Step (5) pressing and molding is as follows: Pour the powder into the mold and perform uniaxial pressure cold pressing and cold isostatic pressing to obtain the target blank.

15. The preparation method according to claim 14, characterized in that, The pressure during uniaxial pressure 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.

16. The barium-doped indium titanium oxide target prepared by the preparation method according to any one of claims 1 to 15.

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