Zinc oxide-doped compact target material and preparation method thereof

Abstract

The invention discloses a zinc oxide-doped compact target material and a preparation method thereof, and belongs to the field of coating target material preparation, and the preparation method comprises the following steps: uniformly mixing submicron powder, a dispersant, a binder and water, drying, and preparing the obtained dried and uniformly mixed powder into the zinc oxide-doped compact target material through spark plasma sintering, the submicron powder is selected from metal oxide powder, pre-doped AZO powder or pre-doped GZO powder; the metal oxide powder is composed of ZnO and a doped metal oxide, and the doped metal oxide is selected from Al2O3 or Ga2O3. According to the method, a discharge plasma sintering method is adopted, the doped ZnO-based target material with high density (99.7%) and submicron grain size can be rapidly sintered and prepared, a target material blank is prevented from being located at a high temperature for a long time, the electrical property of the target material can be improved, and the method can be used for magnetron sputtering preparation of a high-quality ZnO-based TCO thin film.

Description

Technical Field

[0001] The invention belongs to the field of coating target material preparation, and in particular relates to a zinc oxide-doped dense target material and a preparation method thereof. Background Art

[0002] Transparent Conductive Oxide (TCO) has a wide range of applications in solar cells, flat panel displays, sensors, and piezoelectric devices due to its large bandgap (about 3.0 eV), good conductivity, high transmittance in the visible light region (>80%), and high reflectivity in the infrared region. Traditional TCO materials are mainly represented by tin-doped indium oxide (ITO) and fluorine-doped tin oxide (FTO). However, indium In in ITO is a rare metal, expensive, and has low reserves in nature. In materials are toxic and easy to cause damage. At the same time, the atomic weight of In and Sn in ITO and FTO is large, and they are easy to penetrate into the substrate during the preparation process, causing material pollution. ZnO-based TCO films (mainly aluminum-doped zinc oxide AZO and gallium-doped zinc oxide GZO) have the advantages of low cost, wide bandgap, low dielectric constant, good temperature stability, high light transmittance, and excellent chemical stability. In addition, they are more stable than ITO in hydrogen plasma, making them a new generation of TCO film materials.

[0003] The preparation of ZnO-based TCO thin films is mainly based on magnetron sputtering, mainly because magnetron sputtering technology has advantages such as good film uniformity, dense film layer, and high film purity. The performance of the ZnO-based target used in magnetron sputtering preparation largely affects the performance of the film produced. Therefore, the preparation of high-quality TCO thin films places high demands on the performance of the target: (1) high purity and high uniformity of the target, requiring low impurity content and uniform structure; (2) high density of the target, high-density target has good electrical and thermal conductivity, high strength, and long service life; (3) small and uniform target grain size can improve the sputtering rate and efficiency, and the formed film is uniform and has excellent performance.

[0004] However, the current preparation methods of ZnO-based targets are mainly based on cold pressing and high-temperature sintering. In order to achieve high density, long-term high-temperature sintering at 1400°C is required. This preparation process easily leads to abnormal crystal growth in the target material and the formation of impurities, which seriously reduces the electrical properties of the target material. ZnO-based targets usually prepared by traditional sintering methods are difficult to meet the preparation requirements of high-transmittance and high-conductivity TCO films. Therefore, it is urgent to improve the preparation method of ZnO-based targets and develop new methods for preparing high-density and fine-grained ZnO-based targets. Summary of the invention

[0005] In order to solve the problem that the traditional ZnO target sintering method easily leads to insufficient density and abnormal grain growth, the present invention provides a zinc oxide-doped dense target and a preparation method thereof, which has a relatively simple process and is suitable for industrial production.

[0006] One of the technical solutions provided by the present invention:

[0007] A method for preparing a zinc oxide-doped dense target material comprises the following steps: mixing submicron powder, a dispersant, a binder and water, drying, and preparing the zinc oxide-doped dense target material by spark plasma sintering the obtained dried mixed powder;

[0008] The submicron powder is selected from metal oxide powder, pre-doped AZO powder or pre-doped GZO powder;

[0009] The metal oxide powder consists of ZnO and doped metal oxide, and the doped metal oxide is selected from Al2O3 or Ga2O3.

[0010] The particle sizes of the ZnO, Al2O3 and Ga2O3 powders are all 0.1-1 μm, and the purity is greater than 99.5%; and / or,

[0011] The particle sizes of the pre-doped AZO powder and the pre-doped GZO powder are both 0.1-1 μm, and the purity is both greater than 99.5%.

[0012] The mass ratio of ZnO to the doped metal oxide is (95:5)-(99:1); and / or,

[0013] The metal ion doping ratios of the pre-doped AZO and pre-doped GZO powders are both 0.5-4 mol%.

[0014] The amount of the dispersant added is 0.2-0.3wt% of the mass of the submicron powder; and / or,

[0015] The amount of the binder added is 2-4 wt % of the mass of the submicron powder.

[0016] The invention controls the amount of dispersant and binder added to ensure that different metal oxide particles are mixed evenly while ensuring that the powders can be tightly combined, maintaining the best powder cluster state, and laying a foundation for the subsequent preparation of dense blocks.

[0017] The dispersant is one or more of polyacrylic acid, polyvinyl pyrrolidone and citric acid; and / or,

[0018] The binder is one or more of polyvinyl alcohol, polyethylene glycol and carboxymethyl cellulose.

[0019] The mixing is performed by high energy ball milling.

[0020] The high-energy ball milling method uses zirconium oxide grinding balls, the ball-to-material ratio is 8:1, the slurry solid content is 80%, the ball mill revolution speed is 400-600rpm, and the ball milling time is 1-6h.

[0021] The spark plasma sintering comprises the following steps: placing the dry mixed powder in a graphite grinder, applying a pressure of 5-60 MPa, adjusting the vacuum degree, and then adopting a rapid sintering method to prepare a dense target material doped with zinc oxide.

[0022] The rapid sintering method is to heat the sample to 1100-1300° C. at a rate of 30-100° C. / min, keep the temperature for 1-10 min, and then cool to room temperature.

[0023] The conventional thermal sintering method easily leads to the formation of non-target ZnAl2O4 crystal phase, thereby reducing the photoelectric performance of the target material. The present invention adopts spark plasma sintering. By gradually increasing the temperature and sintering at high temperature, the density of the AZO or GZO block can be improved while further reducing the grain boundary defects and pores; it promotes a rapid solid phase reaction between Al2O3 or Ga2O3 and ZnO, and can also inhibit the formation of non-target ZnAl2O4 crystal phase.

[0024] Patent CN118373679A also uses spark plasma sintering when preparing AZO ceramic targets. The sintering temperature used is 200-400°C. Under such low temperature conditions, sufficient densification cannot be achieved, and residual voids exist in the prepared target, making it impossible to obtain a high-quality target.

[0025] The second technical solution provided by the present invention is:

[0026] A zinc oxide-doped dense target material prepared by the above preparation method.

[0027] Compared with the prior art, the present invention has the following advantages and technical effects:

[0028] The present invention adopts a spark plasma sintering method, which can quickly sinter and prepare a doped ZnO-based target material with high density (99.7%) and submicron grain size, avoiding the target material blank being at high temperature for a long time, which is beneficial to improving the electrical properties of the target material and can be used for magnetron sputtering preparation of high-quality ZnO-based TCO thin films.

[0029] The present invention uses metal oxide powder, pre-doped AZO powder or pre-doped GZO powder as raw materials, controls the particle size and purity of the raw materials, combines a spark plasma sintering method, and controls the heating rate and the sintering temperature during the sintering process to prepare a high-density, fine-grained ZnO-based target material, which has a uniform organizational structure and good conductive properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, 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 labor.

[0031] Figure 1 This is a SEM image of the zinc oxide-doped dense target prepared in Example 1;

[0032] Figure 2 This is a SEM image of the zinc oxide-doped dense target prepared in Example 3;

[0033] Figure 3 This is the SEM image of the AZO ceramic target prepared in Comparative Example 1. DETAILED DESCRIPTION

[0034] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0035] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0036] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0037] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to the skilled artisan. The present invention description and examples are exemplary only.

[0038] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0039] The room temperature in the present invention refers to 25±2°C.

[0040] Spark plasma sintering (SPS) is a powder metallurgy sintering technology that loads metal, ceramic and other powders into a mold, applies a specific sintering power supply and pressing pressure to the sintering powder using upper and lower punches and powered electrodes, and completes the process through discharge activation, thermoplastic deformation and cooling. The basic principle of spark plasma sintering is to use direct current pulse current to directly sinter. During the sintering process, the discharge plasma generated instantly when the DC pulse current is passed through the electrode causes each particle inside the sintered body to evenly generate Joule heat and activate the particle surface. At the same time, effective discharge between particles can generate local high temperature, causing local melting of the surface and peeling of surface materials, thereby removing impurities and adsorbed gases on the surface of the powder particles. The effect of the electric field accelerates the diffusion process, which helps to achieve fast and high-quality sintering.

[0041] Patent CN118373679A provides a method for preparing AZO ceramic target material based on discharge plasma assisted cold sintering. The preparation method of the AZO ceramic target material is as follows: firstly, a zinc acetate solution and an aluminum nitrate solution are mixed to obtain a mixed solution with a pH value of 8-9; the mixed solution is charged into a reactor, and then placed in a drying oven for drying and heat preservation to obtain a hydrothermal product AZO precursor powder; after the AZO precursor powder is subjected to stirring and dispersion treatment, it is filtered and washed by a water circulation type suction filter, and then low-temperature drying is performed to obtain AZO wet powder; the AZO wet powder is placed in a mold for pre-pressing to obtain an AZO blank; The AZO blank is placed in a spark plasma sintering furnace together with a mold, and a semi-finished target is obtained by spark plasma assisted cold sintering at low temperature and high pressure; the semi-finished target is mechanically processed, brazed with a copper back plate, cleaned, dried, and vacuum packaged to obtain a finished AZO ceramic target. The prior art prepares AZO precursor powder by mixing zinc acetate solution and aluminum nitrate solution. This method results in a large powder particle size and uneven distribution, which affects the subsequent sintering effect and the density of the target. Due to the large raw material particle size, uneven distribution and limitations of the sintering process, there are many defects and pores inside the target, which reduces the conductivity.

[0042] The invention provides a method for preparing a dense target material doped with zinc oxide, comprising the following steps: using high-purity submicron-grade ZnO, Al2O3, Ga2O3 oxide powders or pre-doped AZO and GZO powders as raw materials, mixing oxide powders according to appropriate proportions, adding appropriate amounts of dispersants, binders and water, dispersing and further crushing the powder particles by high-energy ball milling, and then drying to obtain uniformly mixed powders; taking a certain amount of the mixed powders, placing them in a graphite grinder, applying a pressure of 5-60 MPa by using a discharge plasma sintering device, and sintering the powders at 10 -3 The dense target material is obtained by rapidly heating to 1100-1300°C in a vacuum environment of Pa, keeping the temperature for 1-10 minutes, and then cooling to room temperature. Through the present invention, a doped ZnO-based target material with high density (99.7%) and submicron grain size is prepared by rapid sintering under pressure and vacuum conditions using a discharge plasma sintering method, which provides a new way for high-quality ZnO-based coating targets and is beneficial to improving the performance of magnetron sputtering transparent conductive films.

[0043] An embodiment of the present invention provides a method for preparing a doped zinc oxide dense target material, comprising the following steps: mixing submicron powder, a dispersant, a binder and water, drying, placing the dried and fully uniformly mixed powder into a graphite mold with a carbon barrier layer on the inner wall, and preparing the doped zinc oxide dense target material by spark plasma sintering the obtained dried mixed powder; the submicron powder is selected from metal oxide powder, pre-doped AZO powder or pre-doped GZO powder; the metal oxide powder is composed of ZnO and doped metal oxide, and the doped metal oxide is selected from Al2O3 or Ga2O3.

[0044] When the prior art including patent CN118373679A prepares ceramic targets by spark plasma sintering, the pre-calcined samples are directly placed in a graphite mold, which will cause graphite to penetrate into the target material and make it impossible to prepare high-quality targets. The present invention places the dry, fully and uniformly mixed powder into a graphite mold with a carbon barrier layer (molybdenum foil or tungsten foil) on the inner wall, which effectively prevents graphite from penetrating into the target material during the calcination process.

[0045] In some embodiments of the present invention, the particle sizes of the ZnO, Al2O3 and Ga2O3 powders are all 0.1-1 μm, and the purity is greater than 99.5%; the particle sizes of the pre-doped AZO powder and the pre-doped GZO powder are all 0.1-1 μm, and the purity is greater than 99.5%.

[0046] The present invention adopts submicron powder as raw material, and by limiting the powder particle size and purity, ensures that the raw material has a smaller particle size, a higher specific surface area and a higher purity, which is conducive to forming a tighter structure during the sintering process, thereby improving the density of the target material, and the grains of the obtained target material are finer and more uniform.

[0047] In some embodiments of the present invention, the mass ratio of ZnO to the doped metal oxide is (95:5)-(99:1); the metal ion doping ratios of the pre-doped AZO and pre-doped GZO powders are both 0.5-4 mol%.

[0048] The present invention achieves a balance between optical and electrical properties by limiting the mass of ZnO and doped metal oxides and the metal ion doping ratio of pre-doped AZO and pre-doped GZO powders, which helps to obtain AZO and GZO targets with high optical transmittance and electrical conductivity.

[0049] In some embodiments of the present invention, the added amount of the dispersant is 0.2-0.3wt% of the mass of the submicron powder; and the added amount of the binder is 2-4wt% of the mass of the submicron powder.

[0050] In some embodiments of the present invention, the dispersant is one or more of polyacrylic acid, polyvinyl pyrrolidone and citric acid; the binder is one or more of polyvinyl alcohol, polyethylene glycol and carboxymethyl cellulose.

[0051] In some embodiments of the present invention, the mixing is performed by high-energy ball milling, wherein the high-energy ball milling method uses zirconia grinding balls, a ball-to-material ratio of 8:1, a slurry solid content of 80%, a ball mill revolution speed of 400-600rpm, and a ball milling time of 1-6h.

[0052] In some embodiments of the present invention, the spark plasma sintering comprises the following steps: placing the dry mixed powder in a graphite mold, applying a pressure of 5-60 MPa, and adjusting the vacuum degree to 10 -3 Pa level, and then the rapid sintering method is used to prepare the dense target material doped with zinc oxide.

[0053] In some embodiments of the present invention, the rapid sintering method is to heat the sample to 1100-1300°C at a rate of 30-100°C / min, keep the temperature for 1-10 min, and then cool to room temperature.

[0054] The embodiment of the present invention also provides a zinc oxide-doped dense target prepared by the above method.

[0055] The source of the pre-doped AZO powder and GZO powder in the embodiments of the present invention is Shanghai Aladdin Biochemical Technology Co., Ltd.

[0056] In the embodiments of the present invention, ZnO, Al2O3, Ga2O3 powders and other reagents are purchased from the market.

[0057] Example 1 A method for preparing a zinc oxide-doped dense target

[0058] First, submicron ZnO and Al2O3 powders were weighed at a mass ratio of 97:3, and then 0.2% of the total mass of the powders were added with polyacrylic acid and 3% of polyethylene glycol; ZrO2 grinding balls with a corresponding diameter of 5 mm were weighed at a ball-to-material ratio of 8:1, and placed in a high-energy ball mill, and then the powders, polyacrylic acid and polyethylene glycol were added to the high-energy ball mill; deionized water was added to the ball mill to make the slurry solid content of 80%, and the ball mill was sealed; then the ball mill was placed in a planetary high-energy ball mill, and the speed was set to 500rpm, an intermittent ball milling method of 5min rotation and 3min rest was adopted, and the total grinding time was 4h (i.e., 30 cycles were set); after the ball milling was completed, the wet slurry was taken out and dried in a vacuum drying oven at 100℃ for 6h to obtain a dry, fully uniform mixed powder; an appropriate amount of powder was weighed and loaded into a φ30mm graphite mold with a molybdenum foil on the inner wall, and placed in a discharge plasma sintering furnace chamber, a pressure of 50MPa was applied to the upper and lower pressure rods of the mold, and the sintering furnace chamber was evacuated to a vacuum degree of 5×10 -3 Pa; the green body is heated under pressure and vacuum in a spark plasma sintering furnace at a heating rate of 50°C / min to 1150°C, kept warm for 5 minutes, and finally cooled to room temperature with the furnace to obtain a dense target material doped with zinc oxide, the relative density of the target material can reach 99.5%, and the average grain size is less than 1μm. Figure 1 This is the SEM image of the dense target material doped with zinc oxide prepared in Example 1. Figure 1 It can be seen that the target material has a dense structure and few pores.

[0059] Example 2

[0060] First, submicron ZnO and Ga2O3 powders were weighed at a mass ratio of 95:5, and then 0.3% of the total mass of the powder was added with polyacrylic acid and 4% of polyethylene glycol; ZrO2 grinding balls with a corresponding diameter of 5 mm were weighed at a ball-to-material ratio of 8:1, and placed in a high-energy ball mill, and then the powders, polyacrylic acid and polyethylene glycol were added to the high-energy ball mill; deionized water was added to the ball mill to make the slurry solid content of 80%, and the ball mill was sealed; then the ball mill was placed in a planetary high-energy ball mill, and the speed was set to The slurry was taken out and dried in a vacuum oven at 100 °C for 6 h to obtain a dry, fully uniform mixed powder. An appropriate amount of powder was weighed and loaded into a graphite mold with a diameter of 30 mm and a tungsten foil on the inner wall, which was placed in a discharge plasma sintering furnace chamber. A pressure of 50 MPa was applied to the upper and lower pressure rods of the mold, and the sintering furnace chamber was evacuated to a vacuum degree of 5 × 10 -3 Pa; the green body is heated under pressure and vacuum in a spark plasma sintering furnace at a heating rate of 50°C / min to 1150°C, kept warm for 5 minutes, and finally cooled to room temperature with the furnace to obtain a dense target material doped with zinc oxide, the relative density of the target material can reach 99.5%, and the average grain size is less than 1μm.

[0061] Example 3

[0062] Submicron pre-doped AZO powder (wherein the Al metal ion doping ratio is 0.5 mol%) with an average particle size of less than 0.5 μm is weighed, and then 0.2% of the mass of the powder is polyacrylic acid and 3% of polyethylene glycol are added; ZrO2 grinding balls with a corresponding diameter of 5 mm are weighed according to a ball-to-material ratio of 8:1, and placed in a high-energy ball mill, and then the powder, polyacrylic acid and polyethylene glycol are added to the high-energy ball mill; deionized water is added to the ball mill to make the slurry solid content 80%, and the ball mill is sealed; then the ball mill is placed on a planetary high-energy mill. In the ball mill, the speed was set to 400 rpm, and an intermittent ball milling method of 5 min rotation and 2 min rest was adopted, and the total grinding time was 2 h (i.e., 17 cycles were set); after the ball milling was completed, the wet slurry was taken out and dried in a vacuum drying oven at 100 °C for 6 h to obtain a dry, fully and uniformly mixed powder; an appropriate amount of powder was weighed and loaded into a graphite mold with a diameter of 30 mm and a molybdenum foil on the inner wall, and placed in a discharge plasma sintering furnace chamber; a pressure of 50 MPa was applied to the upper and lower pressure rods of the mold, and the sintering furnace chamber was evacuated to a vacuum degree of 5×10 -3Pa; the green body is heated under pressure and vacuum in a spark plasma sintering furnace at a heating rate of 50°C / min to 1200°C, kept at that temperature for 10 minutes, and finally cooled to room temperature with the furnace to obtain a dense doped zinc oxide dense target. The relative density of the target can reach 99.7%, and the average grain size is less than 1μm. Figure 2 This is the SEM image of the dense target material doped with zinc oxide prepared in Example 3. Figure 2 It can be seen that the target material has a dense structure with almost no pores and defects.

[0063] Example 4

[0064] Submicron pre-doped GZO powder (wherein the Ga metal ion doping ratio is 3.5 mol%) is weighed, and the average particle size of the powder particles is less than 0.5 μm. Then, 0.2% of the mass of the powder is polyacrylic acid and 4% of polyethylene glycol are added; ZrO2 grinding balls with a corresponding diameter of 5 mm are weighed according to a ball-to-material ratio of 8:1, and placed in a high-energy ball mill, and then the powder, polyacrylic acid and polyethylene glycol are added to the high-energy ball mill; deionized water is added to the ball mill to make the slurry solid content 80%, and the ball mill is sealed; then the ball mill is placed in a planetary high-energy mill. In the ball mill, the speed was set to 400 rpm, and an intermittent ball milling method of 5 min rotation and 2 min rest was adopted, and the total grinding time was 2 h (i.e., 17 cycles were set); after the ball milling was completed, the wet slurry was taken out and dried in a vacuum drying oven at 100 °C for 6 h to obtain a dry, fully and uniformly mixed powder; an appropriate amount of powder was weighed and loaded into a graphite mold with a diameter of 30 mm and a molybdenum foil on the inner wall, and placed in a discharge plasma sintering furnace chamber; a pressure of 50 MPa was applied to the upper and lower pressure rods of the mold, and the sintering furnace chamber was evacuated to a vacuum degree of 5×10 -3 Pa; the green body is heated in a spark plasma sintering furnace under pressure and vacuum, with a heating rate of 90°C / min, raised to 1200°C, kept warm for 5 minutes, and finally cooled to room temperature with the furnace to obtain a dense doped zinc oxide dense target. The relative density of the target can reach 99.5%, and the average grain size is less than 1μm.

[0065] Comparative Example 1

[0066] According to Example 3 in patent CN118373679A, AZO ceramic target was prepared. Figure 3 This is the SEM image of the AZO ceramic target prepared in Comparative Example 1. Figure 3 It can be seen that the target material has many pores in the structure.

[0067] Comparative Example 2

[0068] This comparative example uses the traditional thermal sintering method to prepare the target:

[0069] S1. Weigh submicron pre-doped AZO powder, in which the doping ratio of aluminum (Al) metal ions is 2 mol%, and the average particle size of the powder particles is less than 0.5 μm. Add 0.2% polyacrylic acid and 4% polyethylene glycol as additives to improve the dispersibility of the powder;

[0070] S2. Weigh ZrO2 grinding balls with a diameter of 5 mm corresponding to the mass ratio of powder according to the ball-to-material ratio of 8:1, add the powder, polyacrylic acid and polyethylene glycol into a high-energy ball mill, add deionized water into the ball mill to make the solid content of the slurry reach 80%, and then seal the ball mill for ball milling.

[0071] The ball milling process is as follows: the ball mill is placed in a planetary high-energy ball mill, the speed is set to 400 rpm, and an intermittent ball milling method is adopted, that is, rotation for 5 minutes and stop for 2 minutes, and the total grinding time is 2 hours (a total of 17 cycles). After the ball milling is completed, the wet slurry is taken out and dried in a vacuum drying oven at 100°C for 6 hours to obtain a dry and fully uniformly mixed powder.

[0072] S3. Apply uniform pressure through cold isostatic pressing (CIP) equipment to press the dried powder into a mold;

[0073] S4. Place the pressed green body into a conventional sintering furnace and slowly heat it to 1350°C to avoid cracking of the green body caused by rapid heating. Keep it at this temperature for 4 hours to ensure densification. Finally, cool it to room temperature with the furnace to obtain a dense AZO target.

[0074] Performance Test:

[0075] The present invention uses a four-probe method to measure the conductivity of the target materials prepared in Examples 1-4 and Comparative Examples 1-2. The measurement results are shown in Table 1.

[0076] Table 1

[0077]

[0078] The above are only preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for preparing a zinc oxide-doped dense target, characterized in that: The following steps are involved: The submicron powder, dispersant, binder and water are mixed and dried, and the dried mixed powder is sintered by spark plasma to prepare the zinc oxide doped dense target; The submicron powder is selected from metal oxide powder, pre-doped AZO powder or pre-doped GZO powder; The metal oxide powder consists of ZnO and doped metal oxide, and the doped metal oxide is selected from Al2O3 or Ga2O3.

2. The method for preparing a zinc oxide-doped dense target according to claim 1, characterized in that: The particle sizes of the ZnO, Al2O3 and Ga2O3 powders are all 0.1-1 μm, and the purity is greater than 99.5%; and / or, The particle sizes of the pre-doped AZO powder and the pre-doped GZO powder are both 0.1-1 μm, and the purity is both greater than 99.5%.

3. The method for preparing a zinc oxide-doped dense target according to claim 1, characterized in that: The mass ratio of ZnO to the doped metal oxide is (95:5)-(99:1); and / or, The metal ion doping ratios of the pre-doped AZO and pre-doped GZO powders are both 0.5-4 mol%.

4. The method for preparing a zinc oxide-doped dense target according to claim 1, characterized in that: The amount of the dispersant added is 0.2-0.3 wt% of the mass of the submicron powder; and / or, The amount of the binder added is 2-4 wt % of the mass of the submicron powder.

5. The method for preparing a zinc oxide-doped dense target according to claim 1, characterized in that: The dispersant is one or more of polyacrylic acid, polyvinyl pyrrolidone and citric acid; and / or, The binder is one or more of polyvinyl alcohol, polyethylene glycol and carboxymethyl cellulose.

6. The method for preparing a zinc oxide-doped dense target according to claim 1, characterized in that: The mixing is performed by high energy ball milling.

7. The method for preparing a zinc oxide-doped dense target according to claim 6, characterized in that: The high-energy ball milling method uses zirconium oxide grinding balls, the ball-to-material ratio is 8:1, the slurry solid content is 80%, the ball mill revolution speed is 400-600rpm, and the ball milling time is 1-6h.

8. The method for preparing a zinc oxide-doped dense target according to claim 1, characterized in that: The spark plasma sintering comprises the following steps: placing the dry mixed powder in a graphite grinder, applying a pressure of 5-60 MPa, adjusting the vacuum degree, and then adopting a rapid sintering method to prepare a dense target material doped with zinc oxide.

9. The method for preparing a zinc oxide-doped dense target according to claim 8, characterized in that: The rapid sintering method is to heat the sample to 1100-1300° C. at a rate of 30-100° C. / min, keep the temperature for 1-10 min, and then cool to room temperature.

10. A zinc oxide-doped dense target, characterized in that: It is prepared by the preparation method according to any one of claims 1 to 9.

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