Preparation method of high-density indium tin zinc oxide sputtering target material

Abstract

The invention discloses a preparation method of a high-density indium tin zinc oxide sputtering target material, which comprises the following steps: S1, mixing indium oxide powder, tin oxide powder and zinc oxide powder to obtain mixed powder; then mixing the obtained mixed powder with a dispersing agent, a binding agent and deionized water to obtain ITZO slurry; sequentially carrying out ball milling and sand milling on the ITZO slurry to obtain an ITZO slurry dispersion; s2, the obtained ITZO slurry dispersion is subjected to pressure slip casting, drying and degreasing, and a sputtering target dry biscuit is obtained; and S3, sintering the sputtering target material dry biscuit by adopting a step variable temperature method to obtain the indium tin zinc oxide sputtering target material. The compactness of the prepared indium tin zinc oxide sputtering target material can reach 99.8% or above; according to the method, grain controllability of the ITZO sputtering target material can be achieved by regulating and controlling sintering process parameters, a large-size sputtering target material biscuit can be prepared through a slip casting method, operation is easy and convenient, and cost is saved.

Description

Technical Field

[0001] The invention belongs to the technical field of photoelectric target material preparation, and in particular relates to a method for preparing a high-density indium tin zinc oxide sputtering target material. Background Art

[0002] High-density indium tin zinc oxide sputtering targets have broad application potential in the fields of liquid crystal displays, organic optoelectronic devices, solar cells, sensors, etc. In liquid crystal displays, ITZO can be used as a transparent conductive layer to improve the transparency and performance of the display; in organic optoelectronic devices, it can be used as an electrode material to promote electron transport and photoelectric conversion efficiency; in solar cells, it can be used as a transparent electrode to improve light absorption and charge separation efficiency.

[0003] The performance of ITZO thin films depends largely on the performance of ITZO sputtering targets. In order to obtain ITZO thin films with excellent optoelectronic properties, the ITZO sputtering targets are required to have high purity, high density and uniform organizational structure.

[0004] Chinese patent CN202310719195.4 discloses a method for preparing a high-density IZTO target material, which is mainly prepared by dry molding-cold isostatic pressing. The grain size is large and the target material size is small, and the organizational structure is not uniform. In addition, the precision requirements for the mold during molding are high, and the damage to the mold is large. However, slip injection molding is simple to operate and can prepare larger-sized ITZO sputtering target blanks.

[0005] In the preparation process of existing ITZO sputtering targets, the commonly used sintering method is atmospheric pressure sintering. There are one-step sintering and two-step sintering methods. Among them, one-step sintering is to sinter the sputtering target blank to a certain temperature, keep it warm for a certain period of time, and then directly cool it to room temperature; two-step sintering is to quickly sinter the sputtering target blank to a higher temperature first, then cool it to a certain temperature, keep it warm for a certain period of time, and then cool it to room temperature. The two-step sintering method can obtain a uniform and refined structure. In addition, the sintering process also affects the density of ITZO sputtering targets. Summary of the invention

[0006] In view of the problems existing in the prior art, the present invention aims to provide a method for preparing a high-density indium tin zinc oxide sputtering target.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] A first aspect of the present invention provides a method for preparing a high-density indium tin zinc oxide sputtering target, comprising the following steps:

[0009] S1. Mix indium oxide powder, tin oxide powder and zinc oxide powder to obtain a mixed powder; wherein the mass ratio of the indium oxide powder, tin oxide powder and zinc oxide powder is 40% to 65%: 10% to 15%: 20% to 40%; the total mass percentage of the indium oxide powder, tin oxide powder and zinc oxide powder is 100%; then mix the obtained mixed powder with a dispersant, a binder and deionized water to obtain ITZO slurry; then ball mill and sand mill the ITZO slurry in sequence to obtain an ITZO slurry dispersion;

[0010] S2, subjecting the obtained ITZO slurry dispersion to pressure casting, drying, and degreasing to obtain a sputtering target dry blank;

[0011] S3, placing the sputtering target dry blank in a vacuum atmosphere and sintering it by a step temperature change method to obtain an indium tin zinc oxide sputtering target.

[0012] Preferably, in step S1, zirconia balls are used in the ball milling process, and the mass ratio of the zirconia balls to the mixed powder is 1:1.

[0013] Preferably, in step S1, the ball milling rate is 200-300 r / min, and the ball milling time is 3-24 h; the sand milling speed is 1500-2000 r / min, and the sand milling time is 5-8 h.

[0014] Preferably, the dispersant is polyacrylic acid (PAA); and the binder is polyvinyl alcohol (PVA).

[0015] Preferably, in step S1, the mass ratio of the mixed powder to the dispersant, the binder and the deionized water is 100:1-2:0.1-0.5:18-25, and more preferably 100:1.2:0.5:20.

[0016] Preferably, in step S2, before pressure grouting, the ITZO slurry dispersion is first subjected to vacuum treatment to remove bubbles in the slurry, and the grouting pressure is adjusted to 0.2-0.3 MPa by vacuum treatment, and the pressure is maintained for 10-15 hours.

[0017] Preferably, in step S2, the drying temperature is 30-40°C, and the drying is stopped when the mass of the sputtering target blank no longer changes.

[0018] Preferably, in step S2, the degreasing is carried out in a muffle furnace, the degreasing temperature is 500-750° C., and the degreasing time is 15-20 hours.

[0019] Preferably, in step S3, a step temperature change method is used for sintering, and the sintering is carried out in two stages under an oxygen atmosphere. The specific process includes: first, oxygen is introduced at a flow rate of 3 to 5 L / min, and then the temperature is raised to the first step temperature T1, T1 is 1500 to 1520°C, and kept warm for 5 to 15 hours; then the temperature is lowered to the second step sintering temperature T2, T2 is 1420 to 1480°C, and kept warm for 20 to 30 hours.

[0020] Preferably, the heating rate is 2-5°C / min, more preferably 3°C / min; the cooling rate is 2-5°C / min, more preferably 3°C / min.

[0021] A second object of the present invention is to provide a high-density indium tin zinc oxide sputtering target prepared by the above preparation method.

[0022] The present invention has the following beneficial effects:

[0023] The density of the indium tin zinc oxide sputtering target prepared by the invention reaches more than 99%; the grain size of the ITZO sputtering target can be controlled by adjusting the sintering process parameters; a large-sized sputtering target blank can be prepared by the slip casting method, and the operation is simple and cost-saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 The microstructure of the indium tin zinc oxide sputtering target obtained in Example 1;

[0026] Figure 2 This is the grain orientation of the indium tin zinc oxide sputtering target obtained in Example 1. DETAILED DESCRIPTION

[0027] In the following description, for the purpose of illustration rather than limitation, specific details such as specific system structures and technologies are provided to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may also be implemented in other embodiments without these specific details.

[0028] Example 1

[0029] A method for preparing a high-density indium tin zinc oxide sputtering target comprises the following steps:

[0030] S1. Weigh 540 g of indium oxide powder, 150 g of tin oxide powder and 310 g of zinc oxide powder and mix them evenly to obtain a mixed powder; add 200 g of deionized water, 15 g of polyacrylic acid (PAA) and 5 g of polyvinyl alcohol (PVA) to the mixed powder to obtain ITZO slurry, and then ball-mill the obtained ITZO slurry for 12 hours. After the slurry is opened, it is transferred to a high-energy sand mill and sand-milled at a sand milling speed of 1500 r / min. The sand milling is stopped until the average particle size of the slurry reaches less than 0.30 μm and the viscosity reaches less than 10 mPa·s to obtain an ITZO slurry dispersion;

[0031] S2, the ITZO slurry dispersion is subjected to pressure injection molding, the injection pressure is 0.3MPa, the pressure holding time is 8h, and a sputtering target blank is obtained, and then the obtained sputtering target blank is dried. After the drying treatment is completed, a degreasing treatment is performed, the degreasing temperature is 750°C, and the degreasing time is 20h, to obtain a sputtering target dry blank;

[0032] S3. The dry blank of the sputtering target is placed in an oxygen atmosphere and sintered by a two-step method. The temperature is first increased to 1500° C. at a heating rate of 3° C. / min, kept at this temperature for 10 hours, and then cooled to 1450° C. at a cooling rate of 3° C. / min, and kept at this temperature for 20 hours to obtain an indium tin zinc oxide sputtering target.

[0033] The density, resistivity, and grain structure of the obtained indium tin zinc oxide sputtering target were measured. The results are shown in Tables 1 and Figure 1-2 .

[0034] Depend on Figure 1 It can be seen that the target material is completely densified, and the grains are small and evenly distributed.

[0035] Depend on Figure 2 It can be seen that the target material is composed of three phases, namely In 2-2x Zn x Sn x O3(ITZO), Zn2-xIn2xSn 1-x O4(ZTO) and Zn3In2O6(IZO) phases.

[0036] Example 2

[0037] A method for preparing a high-density indium tin zinc oxide sputtering target comprises the following steps:

[0038] S1. Weigh 540 g of indium oxide powder, 150 g of tin oxide powder and 310 g of zinc oxide powder and mix them evenly to obtain a mixed powder; add 200 g of deionized water, 15 g of polyacrylic acid (PAA) and 5 g of polyvinyl alcohol (PVA) to the mixed powder to obtain ITZO slurry, and then ball-mill the obtained ITZO slurry for 12 hours. After the slurry is opened, it is transferred to a high-energy sand mill and sand-milled at a sand milling speed of 1500 r / min. The sand milling is stopped until the average particle size of the slurry reaches less than 0.30 μm and the viscosity reaches less than 10 mPa·s to obtain an ITZO slurry dispersion;

[0039] S2, the ITZO slurry dispersion is subjected to pressure injection molding, the injection pressure is 0.4MPa, the pressure holding time is 8h, and a sputtering target blank is obtained, and then the obtained sputtering target blank is dried. After the drying treatment is completed, a degreasing treatment is performed, the degreasing temperature is 750°C, and the degreasing time is 20h, to obtain a sputtering target dry blank;

[0040] S3. The dry blank of the sputtering target is placed in an oxygen atmosphere and sintered by a two-step method. The temperature is first increased to 1500° C. at a heating rate of 3° C. / min, kept at this temperature for 10 hours, and then cooled to 1450° C. at a cooling rate of 3° C. / min, and kept at this temperature for 20 hours to obtain an indium tin zinc oxide sputtering target.

[0041] The density, resistivity, grain structure, etc. of the obtained indium tin zinc oxide sputtering target were measured. The results are shown in Table 1.

[0042] Example 3

[0043] A method for preparing a high-density indium tin zinc oxide sputtering target comprises the following steps:

[0044] S1. Weigh 540 g of indium oxide powder, 150 g of tin oxide powder and 310 g of zinc oxide powder and mix them evenly to obtain a mixed powder; add 200 g of deionized water, 15 g of polyacrylic acid (PAA) and 5 g of polyvinyl alcohol (PVA) to the mixed powder to obtain ITZO slurry, and then ball-mill the obtained ITZO slurry for 12 hours. After the slurry is opened, it is transferred to a high-energy sand mill and sand-milled at a sand milling speed of 1500 r / min. The sand milling is stopped until the average particle size of the slurry reaches less than 0.30 μm and the viscosity reaches less than 10 mPa·s to obtain an ITZO slurry dispersion;

[0045] S2, the ITZO slurry dispersion is subjected to pressure injection molding, the injection pressure is 0.3MPa, the pressure holding time is 8h, and a sputtering target blank is obtained, and then the obtained sputtering target blank is dried. After the drying treatment is completed, a degreasing treatment is performed, the degreasing temperature is 750°C, and the degreasing time is 20h, to obtain a sputtering target dry blank;

[0046] S3. The dry blank of the sputtering target is placed in an oxygen atmosphere and sintered by a two-step method. The temperature is first increased to 1500° C. at a heating rate of 3° C. / min, and kept at this temperature for 10 hours. The temperature is then decreased to 1420° C. at a cooling rate of 3° C. / min, and kept at this temperature for 20 hours to obtain an indium tin zinc oxide sputtering target.

[0047] The density, resistivity, grain structure, etc. of the obtained indium tin zinc oxide sputtering target were measured. The results are shown in Table 1.

[0048] Example 4

[0049] A method for preparing a high-density indium tin zinc oxide sputtering target comprises the following steps:

[0050] S1. Weigh 640 g of indium oxide powder, 140 g of tin oxide powder and 220 g of zinc oxide powder and mix them evenly to obtain a mixed powder; add 200 g of deionized water, 15 g of polyacrylic acid (PAA) and 5 g of polyvinyl alcohol (PVA) to the mixed powder to obtain ITZO slurry, and then ball-mill the obtained ITZO slurry for 12 hours. After the slurry is opened, it is transferred to a high-energy sand mill and sand-milled at a sand milling speed of 1500 r / min. The sand milling is stopped until the average particle size of the slurry reaches less than 0.30 μm and the viscosity reaches less than 10 mPa·s to obtain an ITZO slurry dispersion;

[0051] S2, the ITZO slurry dispersion is subjected to pressure injection molding, the injection pressure is 0.35MPa, the pressure holding time is 8h, and a sputtering target blank is obtained, and then the obtained sputtering target blank is dried. After the drying treatment is completed, a degreasing treatment is performed, the degreasing temperature is 750°C, and the degreasing time is 20h, to obtain a sputtering target dry blank;

[0052] S3. The dry blank of the sputtering target is placed in an oxygen atmosphere and sintered by a two-step method. The temperature is first increased to 1520°C at a heating rate of 3°C / min, and kept at this temperature for 10 hours. The temperature is then decreased to 1450°C at a cooling rate of 3°C / min, and kept at this temperature for 20 hours to obtain an indium tin zinc oxide sputtering target.

[0053] The density, resistivity, grain structure, etc. of the obtained indium tin zinc oxide sputtering target were measured. The results are shown in Table 1.

[0054] Example 5

[0055] A method for preparing a high-density indium tin zinc oxide sputtering target comprises the following steps:

[0056] S1. Weigh 550g of indium oxide powder, 150g of tin oxide powder and 400g of zinc oxide powder and mix them evenly to obtain a mixed powder; add 180g of deionized water, 15g of polyacrylic acid (PAA) and 5g of polyvinyl alcohol (PVA) to the mixed powder to obtain ITZO slurry, and then ball-mill the obtained ITZO slurry for 12h. After the slurry is opened, it is transferred to a high-energy sand mill and sand-milled at a sand milling speed of 1500r / min. The sand milling is stopped until the average particle size of the slurry reaches less than 0.30μm and the viscosity reaches less than 10mPa·s to obtain an ITZO slurry dispersion;

[0057] S2, the ITZO slurry dispersion is subjected to pressure injection molding, the injection pressure is 0.4MPa, the pressure holding time is 8h, and a sputtering target blank is obtained, and then the obtained sputtering target blank is dried. After the drying treatment is completed, a degreasing treatment is performed, the degreasing temperature is 750°C, and the degreasing time is 20h, to obtain a sputtering target dry blank;

[0058] S3. The dry blank of the sputtering target is placed in an oxygen atmosphere and sintered by a two-step method. The temperature is first increased to 1520°C at a heating rate of 3°C / min, and kept at this temperature for 10 hours. The temperature is then decreased to 1450°C at a cooling rate of 3°C / min, and kept at this temperature for 20 hours to obtain an indium tin zinc oxide sputtering target.

[0059] The density, resistivity, grain structure, etc. of the obtained indium tin zinc oxide sputtering target were measured. The results are shown in Table 1.

[0060] Example 6

[0061] A method for preparing a high-density indium tin zinc oxide sputtering target comprises the following steps:

[0062] S1. Weigh 540 g of indium oxide powder, 160 g of tin oxide powder and 400 g of zinc oxide powder and mix them evenly to obtain a mixed powder; add 250 g of deionized water, 10 g of polyacrylic acid (PAA) and 5 g of polyvinyl alcohol (PVA) to the mixed powder to obtain ITZO slurry, and then ball-mill the obtained ITZO slurry for 12 hours. After the slurry is opened, it is transferred to a high-energy sand mill and sand-milled at a sand milling speed of 1500 r / min. The sand milling is stopped until the average particle size of the slurry reaches less than 0.30 μm and the viscosity reaches less than 10 mPa·s to obtain an ITZO slurry dispersion;

[0063] S2, the ITZO slurry dispersion is subjected to pressure injection molding, the injection pressure is 0.4MPa, the pressure holding time is 8h, and a sputtering target blank is obtained, and then the obtained sputtering target blank is dried. After the drying treatment is completed, a degreasing treatment is performed, the degreasing temperature is 750°C, and the degreasing time is 20h, to obtain a sputtering target dry blank;

[0064] S3. The dry blank of the sputtering target is placed in an oxygen atmosphere and sintered by a two-step method. The temperature is first increased to 1520°C at a heating rate of 3°C / min, and kept at this temperature for 10 hours. The temperature is then decreased to 1420°C at a cooling rate of 3°C / min, and kept at this temperature for 20 hours to obtain an indium tin zinc oxide sputtering target.

[0065] The density, resistivity, grain structure, etc. of the obtained indium tin zinc oxide sputtering target were measured. The results are shown in Table 1.

[0066] Comparative Example 1

[0067] It is basically the same as Example 1, except that, S3, the sputtering target material dry blank is placed in an oxygen atmosphere and sintered in a one-step method, the sintering temperature is 1500° C., and the sintering time is 25 hours.

[0068] The density, resistivity, grain structure, etc. of the indium tin zinc oxide sputtering target obtained in Comparative Example 1 were measured. The results are shown in Table 1.

[0069] Comparative Example 2

[0070] The method is basically the same as Example 1, except that, S3, the dry blank of the sputtering target is placed in an oxygen atmosphere and sintered by a two-step method, firstly heating the temperature to 1520°C at a heating rate of 1°C / min, keeping the temperature for 10 hours, and then cooling the temperature to 1200°C at a cooling rate of 1°C / min, keeping the temperature for 20 hours, to obtain an indium tin zinc oxide sputtering target.

[0071] The density, resistivity, grain structure, etc. of the indium tin zinc oxide sputtering target obtained in Comparative Example 2 were measured. The results are shown in Table 1.

[0072] Comparative Example 3

[0073] The method is basically the same as Example 1, except that, in S3, the dry blank of the sputtering target is placed in an oxygen atmosphere and sintered by a two-step method, firstly heating the temperature to 1650°C at a heating rate of 8°C / min, keeping the temperature for 10 hours, and then cooling the temperature to 1420°C at a cooling rate of 8°C / min, keeping the temperature for 20 hours, to obtain an indium tin zinc oxide sputtering target.

[0074] The density, resistivity, grain structure, etc. of the indium tin zinc oxide sputtering target obtained in Comparative Example 3 were measured. The results are shown in Table 1.

[0075] Comparative Example 4

[0076] It is basically the same as Example 1, except that the degreasing temperature is 450°C.

[0077] The density, resistivity, grain structure, etc. of the indium tin zinc oxide sputtering target obtained in Comparative Example 4 were measured. The results are shown in Table 1.

[0078] Comparative Example 5

[0079] It is basically the same as Example 1, except that compression molding is used instead of pressure grouting molding.

[0080] The density, resistivity, grain structure, etc. of the indium tin zinc oxide sputtering target obtained in Comparative Example 5 were measured. The results are shown in Table 1.

[0081] Comparative Example 6

[0082] It is basically the same as Example 1, except that no degreasing is performed.

[0083] The density, resistivity, grain structure, etc. of the indium tin zinc oxide sputtering target obtained in Comparative Example 6 were measured. The results are shown in Table 1.

[0084] Table 1

[0085]

[0086] It can be seen from the results in Table 1 that the indium tin zinc oxide sputtering target prepared in Examples 1-6 has excellent comprehensive performance. The performance parameter results of the indium tin zinc oxide sputtering target prepared in Comparative Example 1 show that the use of one-step sintering will lead to a decrease in the density of the ITZO target and an increase in the grain size. This is because during the two-step sintering, by controlling the temperature, the grain boundary migration can be suppressed while the grain boundary diffusion is kept in an active state, and the density is completed without the grain growing. The performance results of the indium tin zinc oxide sputtering target prepared in Comparative Example 2 show that when the heating and cooling rate is too low, the density of the ITZO target decreases and the grain size increases. This is because the heating and cooling rate is too low, and the target is in the high temperature stage for a longer time during sintering, resulting in continued growth of the grains and volatilization of ZnO. The performance parameter results of the indium tin zinc oxide sputtering target prepared in Comparative Example 3 show that when the heating and cooling rate is too fast, the density of the ITZO target decreases and the grain size decreases. This is because the heating and cooling rate is too low, and the target is in the high temperature stage for a shorter time during sintering, and the grain growth is incomplete. The performance parameter results of the indium tin zinc oxide sputtering target prepared in comparative example 4 show that when the degreasing temperature is lowered, the density of the ITZO target decreases and the grain size increases. This is because when the degreasing temperature is too low, the organic matter that is not completely removed will release gas during the sintering process. These gases cannot escape in time, and will form pores or foam, resulting in an increase in the porosity of the ITZO target. The performance parameter results of the indium tin zinc oxide sputtering target prepared in comparative example 5 show that when the ITZO blank is prepared by compression molding, the density of the ITZO target decreases and the grain size increases. This is because when compression molding is used, a larger ITZO blank with a larger molding size requires greater pressure, and the mold precision requirements are very high, which will cause the internal structure of the blank to be uneven and produce local stress concentration and defects. When using pressure grouting to prepare the ITZO blank, the problem of uneven pressure can be better dealt with by regulating the fluidity of the ITZO slurry. This is also the advantage of the present invention over the existing ITZO target preparation method, that is, when preparing large-size ITZO targets, the present invention has more practical value and economic advantages. The performance parameter results of the indium tin zinc oxide sputtering target prepared in Comparative Example 6 show that when no degreasing treatment is performed, the density of the ITZO target decreases and the grain size increases. This is because direct sintering without degreasing will cause the undegreased organic matter to decompose and release gas during the high-temperature sintering process. When these gases cannot be discharged smoothly, pores or foams will form inside the material, thereby reducing the density and mechanical properties of the target. The indium tin zinc oxide sputtering targets prepared in Examples 1 to 6 of the present invention have a higher density (up to 99.98%), and can solve the problems of uneven blank structure and difficulty in complete densification of the target when preparing large-size ITZO targets.

[0087] The raw materials of indium oxide powder, tin oxide powder and zinc oxide powder used in the present invention have a mass ratio of 40% to 65%: 10% to 15%: 20% to 40%, wherein the higher the proportion of indium oxide is, the higher the density of the ITZO target material is under the same sintering process, and the better the electrical properties are, and the grain size of the large-size ITZO sputtering target material can be controlled by controlling the sintering process parameters.

[0088] The present invention is not limited to the above-mentioned specific implementation modes. Various changes made by ordinary technicians in this field based on the above-mentioned concepts without creative work are all within the protection scope of the present invention.

Claims

1. A method for preparing a high-density indium tin zinc oxide sputtering target, characterized in that: The following steps are involved: S1. Mix indium oxide powder, tin oxide powder and zinc oxide powder to obtain a mixed powder; wherein the mass ratio of the indium oxide powder, tin oxide powder and zinc oxide powder is 40% to 65%: 10% to 15%: 20% to 40%; the total mass percentage of the indium oxide powder, tin oxide powder and zinc oxide powder is 100%; then mix the obtained mixed powder with a dispersant, a binder and deionized water to obtain ITZO slurry; then ball mill and sand mill the ITZO slurry in sequence to obtain an ITZO slurry dispersion; S2, subjecting the obtained ITZO slurry dispersion to pressure casting, drying, and degreasing to obtain a sputtering target dry blank; S3, placing the sputtering target dry blank in a vacuum atmosphere and sintering it by a step temperature change method to obtain an indium tin zinc oxide sputtering target.

2. The method for preparing a high-density indium tin zinc oxide sputtering target according to claim 1, characterized in that: In step S1, zirconia balls are used in the ball milling process, and the mass ratio of the zirconia balls to the mixed powder is 1:

1.

3. The method for preparing a high-density indium tin zinc oxide sputtering target according to claim 1, characterized in that: In step S1, the ball milling rate is 200-300 r / min, and the ball milling time is 3-24 h; the sand milling speed is 1500-2000 r / min, and the sand milling time is 5-8 h.

4. The method for preparing a high-density indium tin zinc oxide sputtering target according to claim 1, characterized in that: The dispersant is polyacrylic acid; the binder is polyvinyl alcohol.

5. The method for preparing a high-density indium tin zinc oxide sputtering target according to claim 1, characterized in that: In step S1, the mass ratio of the mixed powder to the dispersant, the binder and the deionized water is 100:1-2:0.1-0.5:18-25, and more preferably 100:1.2:0.5:

20.

6. The method for preparing a high-density indium tin zinc oxide sputtering target according to claim 1, characterized in that: In step S2, before pressure grouting, the ITZO slurry dispersion is first subjected to vacuum treatment to remove bubbles in the slurry, and the grouting pressure is adjusted to 0.2-0.3 MPa by vacuum treatment, and the pressure is maintained for 10-15 hours.

7. The method for preparing a high-density indium tin zinc oxide sputtering target according to claim 1, characterized in that: In step S2, the drying temperature is 30-40°C; the degreasing temperature is 500-750°C, and the degreasing time is 15-20 hours.

8. The method for preparing a high-density indium tin zinc oxide sputtering target according to claim 1, characterized in that: In step S3, a step temperature change method is used for sintering. The sintering is carried out in two stages under an oxygen atmosphere. The specific process includes: first, oxygen is introduced at a flow rate of 3 to 5 L / min, and then the temperature is raised to the first step temperature T1, T1 is 1500 to 1520°C, and kept warm for 5 to 15 hours; then the temperature is lowered to the second step sintering temperature T2, T2 is 1420 to 1480°C, and kept warm for 20 to 30 hours.

9. The method for preparing a high-density indium tin zinc oxide sputtering target according to claim 1, characterized in that: The heating rate is 2-5°C / min, and the cooling rate is 2-5°C / min.

10. A high-density indium tin zinc oxide sputtering target prepared by the preparation method according to any one of claims 1 to 9.

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