Multi-element synergetic doped ATO target material and preparation method thereof

Abstract

The invention relates to a multi-element synergistic doped ATO target material and a preparation method thereof. Comprising the following steps: 1) uniformly mixing water and a powder dispersant, then adding an oxide 1 (at least one of tantalum pentoxide, niobium pentoxide, vanadium pentoxide, gallium oxide and tungsten trioxide), an oxide 2 (at least one of zinc oxide, copper oxide, cobalt oxide, manganese oxide and cerium oxide) and ATO raw material powder, and mixing and homogenizing to prepare slurry; 2) grinding the slurry and adding a powder forming adhesive; 3) carrying out spray drying granulation on the ground slurry; according to the preparation method, the ATO target material with high compactness (relative density gt, 98.5%) and low resistance (resistivity lt, 5 * 10 <-3 > omega.cm) is prepared through multi-element synergistic doping of the oxide, and the problem that compactness and conductivity of the ATO target material are difficult to consider at the same time in the prior art is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of ceramic target material preparation, and in particular to an antimony tin oxide (ATO) target material synergistically modified by multi-element doping and a preparation method thereof. Background Art

[0002] ATO (antimony tin oxide) targets are gradually replacing ITO targets in the fields of touch screens, solar cells, etc. due to their high conductivity and visible light transmittance. However, there are two major technical bottlenecks in existing ATO targets:

[0003] 1. Densification difficulties: The density under pressureless sintering is generally lower than 95% of the theoretical value. Although hot isostatic pressing can increase the density, the equipment cost increases by more than 50%;

[0004] 2. Poor performance stability: Although single doping can increase the density to 96%, the resistivity increases to 1.2×10-2Ω·cm, and abnormal discharge is prone to occur during sputtering.

[0005] Chinese patent application 202411075108.7 discloses a modified ATO ceramic target and a preparation method thereof. The modified ATO ceramic target uses one of the doped oxides ZnO, Bi2O3, TiO2, and Ta2O5. The modified ATO ceramic target is modified by doping with a specific metal oxide to improve the sintering density of the target. Studies have found that high-valent oxides such as tantalum pentoxide can increase the carrier concentration, but when doped alone, they can cause grain boundary embrittlement and a sintering shrinkage rate of less than 3%. Although low-valent oxides such as zinc oxide can promote densification through the liquid phase, excessive introduction will form a high-resistance phase. Therefore, there is an urgent need to develop a multi-element synergistic doping system that takes into account both densification and electrical properties. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a multi-component synergistically doped ATO target material and a preparation method thereof. The method prepares a high-density, low-resistance ATO target material through multi-component synergistic doping of oxides, thereby solving the problem in the prior art that it is difficult to achieve both densification and conductivity of the ATO target material.

[0007] The technical solution to solve the above technical problems is: a multi-element synergistically doped ATO target, whose raw material components include, by weight: 85.0-97.9 parts of tin oxide, 2.5-10.0 parts of antimony oxide, 0.1-5.0 parts of oxide 1, and 0.2-2.0 parts of oxide 2, wherein the oxide 1 is at least one of tantalum pentoxide, niobium pentoxide, vanadium pentoxide, gallium trioxide, and tungsten trioxide, and the oxide 2 is at least one of zinc oxide, copper oxide, cobalt oxide, manganese oxide, and cerium oxide.

[0008] Preferably, a multi-element synergistically doped ATO target material comprises, by weight, 2.5 to 10.0 parts of antimony oxide, 85.0 to 97.9 parts of tin oxide, 0.1 to 5.0 parts of oxide 1, and 0.2 to 2.0 parts of oxide 2, wherein oxide 1 is one of tantalum pentoxide, niobium pentoxide, and gallium trioxide, and oxide 2 is one or two of zinc oxide, copper oxide, and cerium oxide.

[0009] Preferably, a multi-element synergistically doped ATO target material comprises, by weight, 2.5 to 10.0 parts of antimony oxide, 85.0 to 97.9 parts of tin oxide, 0.1 to 5.0 parts of oxide 1, and 0.2 to 2.0 parts of oxide 2, wherein oxide 1 is one of niobium pentoxide and gallium trioxide, and oxide 2 is one or both of copper oxide and cerium oxide.

[0010] Another technical solution of the present invention is: the preparation method of the above-mentioned multi-element synergistically doped ATO target comprises the following steps:

[0011] 1) Mixing water and a powder dispersant uniformly, then adding raw material powders consisting of oxide 1, oxide 2, antimony oxide, and tin oxide, and mixing uniformly to prepare a slurry;

[0012] 2) Grinding the slurry, then adding a powder forming adhesive to the slurry, and then grinding again;

[0013] 3) spray drying and granulating the slurry treated in step 2) to obtain multi-element doped ATO particles;

[0014] 4) preparing the multinary doped ATO particles into a multinary doped ATO target body;

[0015] 5) Sintering the multi-element doped ATO target body to obtain.

[0016] Furthermore, the powder dispersant in step 1) is one of fulvic acid, polyethylene glycol, polyacrylic acid, and polyvinyl alcohol; the amount of the powder dispersant added is 0.8-3.0% of the total mass of the raw material powder, and the amount of water added is 1.2-2 times the total mass of the raw material powder.

[0017] Furthermore, in step 2), the grinding medium used in the grinding process is wear-resistant zirconia balls, the diameter of the zirconia balls is 0.3-0.5 mm, and the grinding speed is 1000-2800 r / min; the powder molding adhesive is one of polyvinyl alcohol, polyvinyl pyrrolidone, acrylic resin, and polyethylene glycol 8000; the amount of the powder molding adhesive added is 0.8-3.0% of the total mass of the raw powder.

[0018] Furthermore, in step 2), when the slurry is ground to a particle size of D90 = 0.5 to 0.8 μm, a powder forming binder is added to the slurry, and the grinding is continued for 0.5 to 2 hours.

[0019] Furthermore, in step 4), the multinary doped ATO particles are prepared into a multinary doped ATO target blank by using a mold forming + cold isostatic pressing densification method to prepare the multinary doped ATO particles into a multinary doped ATO rotary target or a planar target blank.

[0020] Furthermore, in step 5), the sintering includes two stages of heat treatment and three stages of sintering;

[0021] The two-stage heat treatment is as follows: ① dehydration: heating from room temperature to 250-350°C at a rate of 0.4-1°C / min, and keeping warm for 3-6 hours; ② deesterification: heating from room temperature to 650-780°C at a rate of 0.4-1°C / min, and keeping warm for 3-7 hours;

[0022] The three-stage sintering is as follows: ① pre-sintering: heating to 900-1050°C at a rate of 0.5-1.5°C / min and keeping warm for 3-6 hours; ② sintering: heating to 1100-1200°C at a rate of 0.5-1.5°C / min and keeping warm for 2-6 hours; ③ density enhancement: heating to 1250-1400°C at a rate of 0.4-1°C / min and keeping warm for 4-10 hours.

[0023] Technical mechanism of the invention

[0024] Oxide 1 (Ta2O5 / Nb2O5): High-valent pentavalent tantalum ion (Ta 5+ ) or pentavalent niobium ion (Nb 5+ ) is introduced into the crystal structure of tin dioxide (SnO2), contributing a free electron to the conduction band of SnO2. The doping process directly leads to a significant increase in the concentration of free electrons in the material. After Ta2O5 / Nb2O5 doping, the carrier concentration is increased to 1.5×10 20 cm -3 , significantly improving the electrical conductivity of the material.

[0025] Oxide 2 (ZnO / CuO): ZnO doping, Zn 2+ During high-temperature sintering, it segregates at the SnO2 grain boundaries to form a Zn2SnO4 liquid phase (DSC detects a clear endothermic peak at 1150°C). This liquid phase effectively drives the densification of the material by promoting particle rearrangement and dissolution-precipitation processes. At the same time, the liquid phase (and the second phase that may form after cooling) acts as a powerful grain boundary pinner, significantly inhibiting the abnormal growth of grains, ultimately obtaining a fine, uniform microstructure with an average grain size of ≤2μm, which is crucial for optimizing the material's mechanical strength, electrical uniformity, and reliability.

[0026] The present invention dopes oxide 1 (at least one of tantalum pentoxide, niobium pentoxide, vanadium pentoxide, gallium trioxide, and tungsten trioxide) and oxide 2 (at least one of zinc oxide, copper oxide, cobalt oxide, manganese oxide, and cerium oxide) during the preparation process of the ATO target. Through the coordinated doping of two or more oxides, it is possible to prepare a high-performance, high-density, low-resistance doped tin antimony oxide ceramic target. The ATO target prepared by the present invention has a relative density greater than 98.5%, reaching a maximum of 99.61%, and a resistivity less than 5×10 -3 Ω·cm, the minimum is 6.5×10 -4 Ω·cm. Particularly suitable for magnetron sputtering coating process of high-performance transparent conductive films.

[0027] The technical features of a multi-element synergistically doped ATO target and a preparation method thereof of the present invention are further described below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 : Actual picture of the ATO target prepared in Example 1 of the present invention.

[0029] Figure 2 : Actual picture of the ATO target prepared in Example 2 of the present invention.

[0030] Figure 3 : Actual picture of the ATO target prepared in Example 3 of the present invention. DETAILED DESCRIPTION

[0031] To better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments. Those skilled in the art should understand that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0032] Example 1

[0033] A multi-element synergistically doped ATO target material comprises, by weight, 95.9 parts tin oxide (4N purity), 2.5 parts antimony oxide (4N purity), 0.8 parts oxide 1 (4N purity) (tantalum pentoxide), and 0.8 parts oxide 2 (3N purity) (copper oxide). Tin oxide, antimony oxide, oxide 1, and oxide 2 form a raw material powder.

[0034] A method for preparing a multi-element doped ATO target comprises the following steps:

[0035] (1) Slurry preparation: 1.3 times the weight of the raw material powder of water and 1.5% of the weight of the raw material powder of fulvic acid powder dispersant were added to a small sand mill with a volume of 1 L and mixed. Then, 0.8 parts of tantalum pentoxide, 0.8 parts of copper oxide, 2.5 parts of antimony oxide, and 95.9 parts of tin oxide were added in sequence and mixed homogeneously to obtain a slurry.

[0036] (2) The diameter of the grinding beads is 0.3 mm, the mass ratio of zirconium beads to raw material powder is 1.5:0.8, the ball mill speed is 1500 r / min-2500 r / min, and the mixed particles are ball milled to a particle size D90 of 0.5-0.8 μm; 1.5% of the weight of the raw material powder as polyvinyl alcohol adhesive is added, and the ball milling is continued for 0.5 h to 2 h to end the grinding.

[0037] (3) Spray drying at 200-250°C to obtain particles with D50 = 20-50 μm.

[0038] (4) Green blank molding: The mixed powder particles are placed in a mold and pressed into shape. Then, the target body is formed under 200-300 MPa cold isostatic pressing.

[0039] (5) Sintering: The obtained target blank is placed in a sintering furnace. The first stage of the blank degreasing treatment is as follows: ① Dehydration: Raise the temperature from room temperature to 300℃ at a rate of 0.5℃ / min and keep it warm for 4 hours to remove the residual or adsorbed moisture in the multi-element doped ATO target blank; ② Deesterification: Raise the temperature from 300℃ to 750℃ at a rate of 0.5℃ / min and keep it warm for 6 hours to evaporate the binder in the multi-element doped ATO target blank.

[0040] The second stage of sintering is as follows: ① Pre-sintering: heating from 750℃ to 1000℃ at a rate of 1℃ / min and keeping warm for 4 hours; ② Sintering: heating to 1250℃ at a rate of 0.8℃ / min and keeping warm for 4 hours; ③ Density enhancement: heating to 1300℃ at a rate of 0.5℃ / min and keeping warm for 8 hours.

[0041] (6) After machining and polishing, the sintered target material is subjected to density and resistivity tests.

[0042] Examples 2-7

[0043] A multi-element synergistically doped ATO target and preparation method thereof, wherein the raw material powder is composed of tin oxide, antimony oxide, oxide 1, and oxide 2. The preparation method thereof is substantially the same as that of Example 1. The specific composition and weight proportions of the raw material powder are shown in Table 1. The three-stage sintering parameters in the preparation method are shown in Table 2.

[0044] Table 1: Composition of raw material powders of Examples 1-7

[0045]

[0046] Table 2: Three-stage sintering parameters in the preparation methods of Examples 1-7

[0047]

[0048] Comparative Examples 1-4

[0049] The preparation methods of Comparative Examples 1-4 are basically the same as those of Example 1, except that the doped oxides and the maximum sintering temperature (density enhancement temperature) are changed, as shown in Table 3.

[0050] Table 3: Raw material powder composition and maximum sintering temperature of Comparative Examples 1-4

[0051]

[0052] Performance Testing

[0053] The relative density and resistivity of the multi-element doped ATO ceramic targets prepared in Examples 1-7 and Comparative Examples 1-4 were tested, wherein the relative density was tested using the Archimedean drainage method and the resistivity was tested using a resistivity meter. The results are shown in Table 4.

[0054] Table 4: Performance test results

[0055] Relative density% Resistivity (Ω·cm) Example 1 99.55 <![CDATA[3.4×10 -3 ]]> Example 2 98.77 <![CDATA[4.3×10 -3 ]]> Example 3 99.61 <![CDATA[6.5×10 -4 <!-- 4 -->]]> Example 4 98.87 <![CDATA[5.6×10 -3 ]]> Example 5 99.51 <![CDATA[4.2×10 -3 ]]> Example 6 98.93 <![CDATA[6.2×10 -3 ]]> Example 7 99.12 <![CDATA[3.2×10 -3 ]]> Comparative Example 1 92.17 <![CDATA[6.8×10 -2 ]]> Comparative Example 2 87.06 <![CDATA[8.8×10 -2 ]]> Comparative Example 3 99.40 <![CDATA[4.7×10 -2 ]]> Comparative Example 4 97.43 <![CDATA[9.2×10 -2 ]]>

[0056] As can be seen from the above table, for comparative examples 1-2, only oxide 1 is doped. When the sintering temperature reaches 1580°C, the relative density is only 92.17%, and the resistivity is also relatively high; for comparative examples 3-4, only oxide 2 is doped. The relative density can reach 99.4%, but the resistivity is relatively high.

[0057] In Examples 1-7 of the present invention, when oxide 1 and oxide 2 are doped simultaneously, the relative density is the lowest (Example 2) at 98.77%, and the resistivity is also low; in Example 3 (99.61%), the relative density is the highest, and the resistivity is also the lowest at 6.5×10 -4 Ω·cm. This indicates that the performance of the ATO target prepared by doping both oxide 1 and oxide 2 is significantly better than that of the ATO target prepared by doping only oxide 1 or oxide 2.

Claims

1. A multi-element synergistically doped ATO target, characterized in that: The raw material components include, by weight, 85.0 to 97.9 parts of tin oxide, 2.5 to 10.0 parts of antimony oxide, 0.1 to 5.0 parts of oxide 1, and 0.2 to 2.0 parts of oxide 2. The oxide 1 is at least one of tantalum pentoxide, niobium pentoxide, vanadium pentoxide, gallium trioxide, and tungsten trioxide; and the oxide 2 is at least one of zinc oxide, copper oxide, cobalt oxide, manganese oxide, and cerium oxide.

2. The multi-element cooperatively doped ATO target according to claim 1, characterized in that: The raw material components include, by weight, 2.5 to 10.0 parts of antimony oxide, 85.0 to 97.9 parts of tin oxide, 0.1 to 5.0 parts of oxide 1, and 0.2 to 2.0 parts of oxide 2. The oxide 1 is one of tantalum pentoxide, niobium pentoxide, and gallium trioxide; and the oxide 2 is one or two of zinc oxide, copper oxide, and cerium oxide.

3. The multi-element cooperatively doped ATO target according to claim 2, characterized in that: The raw material components include, by weight, 2.5 to 10.0 parts of antimony oxide, 85.0 to 97.9 parts of tin oxide, 0.1 to 5.0 parts of oxide 1, and 0.2 to 2.0 parts of oxide 2. The oxide 1 is one of niobium pentoxide and gallium trioxide, and the oxide 2 is one or both of copper oxide and cerium oxide.

4. The method for preparing a multi-element synergistically doped ATO target according to claim 1, 2 or 3, characterized in that: The following steps are involved: 1) Mix water and powder dispersant evenly, then add raw material powder consisting of oxide 1, oxide 2, antimony oxide and tin oxide, and mix homogeneously to prepare a slurry; 2) Grinding the slurry, then adding powder forming binder to the slurry, and then grinding again; 3) spray drying and granulating the slurry treated in step 2) to obtain multi-element doped ATO particles; 4) preparing the multi-doped ATO particles into a multi-doped ATO target blank; 5) Sintering the multi-element doped ATO target body to obtain the target.

5. The method for preparing a multi-element synergistically doped ATO target according to claim 4, characterized in that: The powder dispersant in step 1) is one of fulvic acid, polyethylene glycol, polyacrylic acid, and polyvinyl alcohol; the amount of the powder dispersant added is 0.8-3.0% of the total mass of the raw material powder, and the amount of water added is 1.2-2 times the total mass of the raw material powder.

6. The method for preparing a multi-element synergistically doped ATO target according to claim 4, characterized in that: In step 2), the grinding medium used in the grinding process is wear-resistant zirconia balls with a diameter of 0.3 to 0.5 mm, and the grinding speed is 1000 to 2800 r / min; the powder molding binder is one of polyvinyl alcohol, polyvinyl pyrrolidone, acrylic resin, and polyethylene glycol 8000; the amount of the powder molding binder added is 0.8 to 3.0% of the total mass of the raw material powder.

7. The method for preparing a multi-element synergistically doped ATO target according to claim 4, characterized in that: In step 2), when the slurry is ground to a particle size of D90 = 0.5 to 0.8 μm, a powder forming binder is added to the slurry and the grinding is continued for another 0.5 to 2 hours.

8. The method for preparing a multi-element synergistically doped ATO target according to claim 4, characterized in that: In step 4), the multinary doped ATO particles are prepared into a multinary doped ATO target blank by using a mold forming + cold isostatic pressing densification method to prepare the multinary doped ATO particles into a multinary doped ATO rotary target or a planar target blank.

9. The method for preparing a multi-element synergistically doped ATO target according to any one of claims 4 to 8, characterized in that: In step 5), sintering includes two stages of heat treatment and three stages of sintering; The two-stage heat treatment is as follows: ① dehydration: heating from room temperature to 250-350°C at a rate of 0.4-1°C / min, and keeping warm for 3-6 hours; ② deesterification: heating from room temperature to 650-780°C at a rate of 0.4-1°C / min, and keeping warm for 3-7 hours; The three-stage sintering is as follows: ① pre-sintering: heating to 900-1050°C at a rate of 0.5-1.5°C / min and keeping warm for 3-6 hours; ② sintering: heating to 1100-1200°C at a rate of 0.5-1.5°C / min and keeping warm for 2-6 hours; ③ density enhancement: heating to 1250-1400°C at a rate of 0.4-1°C / min and keeping warm for 4-10 hours.

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