Preparation method of direct-current magnetron sputtering high-mobility transparent conductive oxide film

Abstract

The invention discloses a preparation method of a direct-current magnetron sputtering high-mobility transparent conductive oxide thin film, which is characterized in that in the step of preparing a target material, spherical, pyramidal and football-shaped indium oxide powder is adopted to prepare the target material, and the mass ratio of the pyramidal and football-shaped indium oxide powder is more than 20%; the contact between the football-shaped powder and other powder is surface-to-surface contact, the contact between the ball-shaped powder and other powder is point contact, and the football-shaped indium oxide powder is beneficial to improving the electron mobility of the target material and the density of the target material while ensuring the flowability of the powder. An oxide film is obtained through sputtering coating of a direct-current magnetron sputtering coating machine, the obtained oxide film is placed in the atmospheric environment and annealed at different temperatures for 30 + / -5 min, the high-mobility transparent conductive oxide film is obtained, the conductivity and transmittance of the ITO film are improved, and the ultrahigh requirement of the transparent conductive oxide film for high mobility is met.

Description

Technical Field

[0001] The invention relates to the technical field, and in particular to a method for preparing a high-mobility transparent conductive oxide film by direct current magnetron sputtering. Background Art

[0002] Transparent conductive oxide films are widely used in photovoltaic solar cells, flat panel displays, touch screens, etc. In recent years, with the advancement of science and technology, solar cells, flat panel displays, etc. have put forward higher requirements on the electrical and optical properties of transparent conductive oxide films.

[0003] Traditional transparent conductive oxide films are mainly made of indium oxide (In 2 O 3 ) based, zinc oxide (ZnO) based and tin oxide (SnO 2 ) base and other materials. Among them, In 2 O 3 ITO thin films based on ITO have become the most widely used transparent conductive oxide thin film materials due to their advantages such as low resistivity, high bandgap, high transmittance, good abrasion resistance and chemical stability. Usually, the preparation methods of ITO thin films include sol-gel method, DC magnetron sputtering method (PVD), radio frequency sputtering method, vacuum evaporation method, pulsed laser deposition, ion enhanced deposition, chemical vapor deposition method and spray pyrolysis method. Among them, DC magnetron sputtering method has the advantages of high production efficiency, good batch stability, good film adhesion and uniform film thickness, so magnetron sputtering coating has become the most mainstream method for preparing ITO thin films in industry.

[0004] However, the mobility of 99:1 ITO films produced by PVD magnetron sputtering is currently less than 80 cm 2 / (V·s), the square resistance of a 100nm thick ITO film after annealing in an atmospheric environment at 200℃ is greater than 50Ω / □. The square resistance of this ITO film is relatively high. In the field of solar cells, on the one hand, it will cause the photogenerated carriers generated inside the cell to be unable to be well transmitted, resulting in carrier recombination, resulting in a decrease in the FF of the cell. On the other hand, due to the large square resistance of the ITO film, the series resistance of the solar cell will also be high. In order to ensure that the internal photogenerated carriers are transported to the external circuit, the metal silver paste gate spacing of the cell needs to be reduced, which will reduce the sunlight incident on the cell, resulting in a decrease in the short-circuit current density Jsc of the cell, and ultimately reduce the photoelectric conversion efficiency of the solar cell.

[0005] For flat panel displays, the sheet resistance of the thin film is too high, and a large amount of heat will be generated due to the Joule effect during the transport of free electrons, thus affecting the performance of the flat panel display device.

[0006] In the prior art, a Chinese invention patent with a patent publication number of CN 116639956 A discloses a method for preparing a target material using indium oxide, titanium oxide, cerium oxide, and tantalum oxide powder to obtain a high mobility film. The mobility of the obtained film is only 73.53 cm 2 / (V·s); In addition, the Chinese invention patent with patent publication number CN 116425514A discloses a method using In 2 O 3 (98.5wt%), TiO 2 (0.55wt%), ZrO 2 (100ppm), HfO 2 (25ppm), CeO 2 (0.65wt%), MoO 3 (0.3wt%) target material sputtering method to form TCO film, but its mobility is only 75cm 2 / (Vs); The mobility of the films obtained by the above two patents is not greater than 80cm 2 / (V·s), which cannot meet the ultra-high requirements of solar cells for TCO films with high mobility. Summary of the invention

[0007] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a method for preparing a high-mobility transparent conductive oxide film by DC magnetron sputtering, so as to improve the conductivity and transmittance of the ITO film and meet the ultra-high requirements of the transparent conductive oxide film for high mobility.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is: a method for preparing a high-mobility transparent conductive oxide film by DC magnetron sputtering, comprising the following steps:

[0009] Target preparation steps:

[0010] Indium oxide powders in the shapes of a sphere, a pyramid and a football are mixed to obtain indium oxide powder, wherein the mass proportion of the indium oxide powders in the shapes of a pyramid and a football in the total indium oxide powder is greater than 20%, the contact between the indium oxide powder in the shape of a football and other powders is surface-to-surface contact, and the contact between the indium oxide powder in the shape of a sphere and other powders is point contact;

[0011] According to the mass percentage, 95-99.4wt% of indium oxide powder and 0.1-4.8wt% of tin oxide powder are first mixed evenly, and then 0.1-0.3wt% of yttrium oxide powder and 0.1-0.4wt% of antimony oxide powder and the rest of tellurium oxide powder are added in sequence, and stirred and mixed evenly to obtain a first powder.

[0012] Then pour the first powder into a sand mill, add dispersant deionized water and 10±5% ethanol, control the solid content at 55±5%, and further sand grind for 1h±0.5 to obtain the first slurry.

[0013] Add the binder polyvinyl alcohol to the first slurry, the content is 0.5±0.2wt.%, grind for 1±0.5h to obtain the second slurry,

[0014] The second slurry is used for spray granulation, the air inlet temperature is 200±50℃, the exhaust temperature is 90±10℃, and the first dry powder is obtained.

[0015] The first dry powder is subjected to cyclone separation to obtain a second dry powder with a particle size of D90 = 300 ± 50 nm.

[0016] The second dry powder is loaded into the rubber mold for filling, ultrasonic assistance is used to increase the tap density of the second dry powder in the mold, and the cold isostatic press is used for compression molding. The pressure is set to 30 ±

[0017] 5MPa and maintain the pressure for 30±5min, then adjust to 280±20MPa and maintain the pressure for 2±0.5h, then gradually reduce the pressure by a gradient of 10±2MPa to release the internal stress and obtain the green body.

[0018] Place the green body into a sintering furnace for high-temperature sintering, introduce 900-1000sccm of air and 20-35sccm of oxygen, control the sintering furnace to heat up to 650±10℃ at a gradient of 0.5±0.1℃ / min, and keep it warm for 3±1h; then heat up to 1500-1600℃ at a gradient of 1±0.2℃ / min, keep it warm for 250±20h, and then reduce the temperature to room temperature at a corresponding rate.

[0019] Then the target material is machined and bound according to the corresponding drawings to obtain a high-mobility sputtering target material;

[0020] In the coating step, a high-mobility sputtering target is installed on a DC magnetron sputtering coating machine, and an oxide film is obtained by sputtering coating with the DC magnetron sputtering coating machine, and the film thickness of the oxide film is controlled to be 100±10nm, and the obtained oxide film is annealed at different temperatures in an atmospheric environment for 30±5min to obtain a high-mobility transparent conductive oxide film.

[0021] In a further technical solution, in the step of preparing the target material, according to the mass percentage, 99wt% of the indium oxide powder and 0.5wt% of the tin oxide powder are first mixed evenly, and then 0.2wt% of the yttrium oxide powder, 0.2wt% of the antimony oxide powder and 0.1wt% of the tellurium oxide powder are added in sequence and stirred to mix evenly.

[0022] In a further technical solution, in the step of preparing the target material, the mass proportion of the indium oxide powder in the shape of a pyramid and a football in the total indium oxide powder is 20-40%.

[0023] In a further technical solution, in the step of preparing the target material, the average particle size of the indium oxide powder is D90=300±20nm, and the average particle size of the tin oxide powder is D90=150±20nm; the mass proportion of the indium oxide powder in the shape of a pyramid and a football in the total indium oxide powder is 20-25%.

[0024] In a further technical solution, the step of preparing the target material adopts a chemical precipitation method to prepare the indium oxide powder in the shape of a football. The indium oxide powder in the shape of a football is a polyhedral structure formed by a plurality of adjacent polygonal terraces.

[0025] In a further technical solution, in the target material preparation step, a plurality of polygonal deposition platforms of the same shape and successively decreasing side lengths are deposited and stacked on top of each of the polygonal platforms on the surface of the football-shaped indium oxide powder, and the top surface of the uppermost polygonal deposition platform is a plane.

[0026] In a further technical solution, in the step of preparing the target material, the football-shaped indium oxide powder has a polyhedral structure whose surface is formed by adjacently splicing together a plurality of quadrilateral terraces, a plurality of pentagonal terraces and a plurality of hexagonal terraces.

[0027] In a further technical solution, the step of preparing the target material is:

[0028] The first powder is poured into the sand mill, and the dispersant deionized water and 10% of the ethanol are added, and the solid content is controlled at 55%, and further sand milled for 1 hour to obtain the first slurry.

[0029] Add the binder polyvinyl alcohol (content 0.5 wt.%) to the first slurry, grind for 1 hour to obtain the second slurry,

[0030] The spray granulation is performed using the second slurry, the air inlet temperature is 200-220° C., the exhaust air temperature is 85-90° C., to obtain the first dry powder,

[0031] The first dry powder is subjected to cyclone separation to obtain the second dry powder with a particle size of D90=300±20 nm,

[0032] The second dry powder is loaded into the rubber mold, and the second dry powder is filled. Ultrasonic wave assist is used to increase the tap density of the second dry powder in the mold, and the mold is pressed by cold isostatic pressing. The pressure is set to 30 MPa and maintained for 30 minutes, then adjusted to 280 MPa and maintained for 2 hours, and then the pressure is gradually reduced by a gradient of 10 MPa to release the internal stress, thereby obtaining the green body.

[0033] The green body was placed in a sintering furnace for high-temperature sintering, 977 sccm of air and 29 sccm of oxygen were introduced, and the sintering furnace was controlled to increase the temperature to 650°C at a gradient of 0.5°C / min and keep it at that temperature for 3 hours; then the temperature was increased to 1560°C at a gradient of 1°C / min and kept at that temperature for 250 hours, and then the temperature was reduced to room temperature at a corresponding rate.

[0034] In a further technical solution, the coating step,

[0035] During the sputtering coating process, the background vacuum of the DC magnetron sputtering coating machine is controlled to be higher than 2×

[0036] 10 -3 Pa, set the sputtering pressure to 0.1-2Pa, the sputtering voltage to 200-500V, the sputtering current to 5-20A, the oxygen / argon partial pressure to 1-10%, and the hydrogen / argon partial pressure to 0-2.8%,

[0037] For planar targets, the sputtering power density is controlled at 0.2-10 W / cm 2 For rotating targets, the sputtering power density is controlled at 2-15kw / m.

[0038] In a further technical solution, the high-mobility transparent conductive oxide film is placed on a hot plate at 170-200° C. and annealed in an atmospheric environment for 30 minutes.

[0039] Compared with the prior art, the present invention has the advantages of improving the conductivity and transmittance of the ITO film, meeting the requirements of the transparent conductive oxide film for high mobility greater than 80cm 2 / (V·S) has extremely high requirements.

[0040] The present invention adopts spherical, pyramidal and football-shaped indium oxide powders to prepare target materials, and the mass proportion of pyramidal and football-shaped indium oxide powders is more than 20%. The contact between the football-shaped powder and other powders is surface-to-surface contact, and the contact between the sphere and other powders is point contact. The football-shaped indium oxide powder is beneficial to improving the electron mobility and density of the target material.

[0041] The patent of this invention adds yttrium oxide powder and antimony oxide powder to the target material formula. These two powders have unique photoelectric properties and can provide excess free electrons to improve the electron mobility of the film. In addition, tellurium oxide powder is added to effectively reduce the oxygen vacancy concentration in the film, reduce the scattering probability generated during electron migration, and improve mobility.

[0042] The invention also adjusts the sputtering parameters of high mobility films. Only by using specific sputtering power, oxygen content, and annealing temperature can a film with a mobility greater than 100cm be prepared. 2 / (V·s) TCO film, which has the outstanding advantages of low sheet resistance and high transmittance, can effectively improve the photoelectric conversion efficiency of solar cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 SEM morphology picture of the soccer ball-shaped indium oxide powder of the present invention.

[0044] Figure 2 This is a schematic diagram of electron transmission between football-shaped powder and spherical powder. DETAILED DESCRIPTION

[0045] Example 1

[0046] A method for preparing a high-mobility transparent conductive oxide film by direct current magnetron sputtering,

[0047] Target preparation steps:

[0048] Indium oxide powders in the shapes of a sphere, a pyramid and a football are mixed to obtain indium oxide powder, wherein the mass proportion of the indium oxide powders in the shapes of a pyramid and a football in the total indium oxide powder is greater than 20%, the contact between the indium oxide powder in the shape of a football and other powders is surface-to-surface contact, and the contact between the indium oxide powder in the shape of a sphere and other powders is point contact;

[0049] The average particle size of indium oxide powder is D90=300nm, and the average particle size of tin oxide powder is D90=150nm;

[0050] The shapes of indium oxide powder include sphere, pyramid and football. The football-shaped indium oxide powder can be seen in Figure 1 As shown, because the football-shaped powders have a better contact area, the contact area increases, the contact characteristics between the powders become better, the conductive path increases significantly, the internal electrons conduct more smoothly between the powders, there are fewer internal defects, the probability of electron scattering is reduced, and the mean free path of electrons becomes longer, so the Hall mobility increases.

[0051] According to the mass percentage, 99wt% of the indium oxide powder and 0.5wt% of the tin oxide powder are first mixed evenly, and then 0.2wt% of the yttrium oxide powder, 0.2wt% of the antimony oxide powder and 0.1wt% of the tellurium oxide powder are added in sequence, and the mixture is stirred and mixed evenly to obtain a first powder.

[0052] Then pour the first powder into a sand mill, add dispersant deionized water and 10% ethanol, control the solid content at 55%, and further sand grind for 1 hour to obtain a first slurry.

[0053] Add 0.5 wt.% of polyvinyl alcohol as a binder to the first slurry, grind for 1 hour to obtain a second slurry.

[0054] The second slurry is used for spray granulation, the air inlet temperature is 200-220°C, the exhaust temperature is 85-90°C, and the first dry powder is obtained.

[0055] The first dry powder is subjected to cyclone separation to obtain a second dry powder with a particle size of D90 = 300 ± 20 nm.

[0056] The second dry powder is loaded into the rubber mold for filling, and ultrasonic assistance is used to increase the tap density of the second dry powder in the mold, and the mold is put into cold isostatic pressing for compression molding. The pressure is set to 30MPa and maintained for 30min, then adjusted to 280MPa and maintained for 2h, and then the pressure is gradually reduced by a gradient of 10MPa to release the internal stress to obtain a green body.

[0057] The green body was placed in a sintering furnace for high-temperature sintering. 977 sccm of air and 29 sccm of oxygen were introduced. The sintering furnace was controlled to increase the temperature to 650°C at a gradient of 0.5°C / min and keep it at that temperature for 3 hours. Then the temperature was increased to 1560°C at a gradient of 1°C / min and kept at that temperature for 250 hours. Then the temperature was reduced to room temperature at a corresponding rate.

[0058] Then the target material is machined and bound according to the corresponding drawings to obtain a high-mobility sputtering target material;

[0059] The coating step includes installing the high-mobility sputtering target on a DC magnetron sputtering coating machine, sputtering the oxide film by the DC magnetron sputtering coating machine, and controlling the film thickness of the oxide film to be 98 nm. The obtained oxide film is placed on a hot plate at 25° C. and annealed in an atmospheric environment for 30 minutes to obtain a high-mobility transparent conductive oxide film.

[0060] During the sputtering coating process, the background vacuum of the DC magnetron sputtering coating machine was controlled to be less than 2E-3Pa, the sputtering power was 1200W, the argon flow rate was 100sccm, the oxygen flow rate was 12sccm, the chamber temperature was 43°C, and the sputtering time was 305s.

[0061] Terminology explanation: Mobility refers to the average drift velocity of carriers generated under unit electric field strength, and its unit is square centimeter / (volt-second). Mobility represents the conductivity of carriers, and it and the concentration of carriers (electrons or holes) determine the conductivity of semiconductors.

[0062] The conductivity of ITO film is determined by the product of the mobility of the film, the carrier concentration and the basic charge, and the basic charge is a certain value. In order to improve the conductivity of ITO film, it can be achieved by increasing the carrier concentration and mobility of ITO film. However, due to the Drude effect, as the carrier concentration of ITO film increases, the ITO film will produce free carrier absorption in the near-infrared region, thereby reducing the transmittance of ITO film in the near-infrared region. Therefore, improving the mobility of the film without increasing the carrier concentration of the ITO film is a practical method for preparing high-transmittance, high-conductivity ITO film.

[0063] The factors that affect the mobility of ITO film include film element content, sputtering power density, sputtering pressure, oxygen partial pressure, annealing temperature, annealing atmosphere and other related parameters.

[0064] Example 2

[0065] A method for preparing a high-mobility transparent conductive oxide film by DC magnetron sputtering. The preparation method of this embodiment is the same as that of Example 1, except that after the oxide film is obtained in the coating step, the obtained oxide film is placed on a hot plate at 170°C and annealed in an atmospheric environment for 30 minutes to obtain a high-mobility transparent conductive oxide film.

[0066] Example 3

[0067] A method for preparing a high-mobility transparent conductive oxide film by DC magnetron sputtering. The preparation method of this embodiment is the same as that of Example 1, except that after the oxide film is obtained in the coating step, the obtained oxide film is placed on a hot plate at 175°C and annealed in an atmospheric environment for 30 minutes to obtain a high-mobility transparent conductive oxide film.

[0068] Example 4

[0069] A method for preparing a high-mobility transparent conductive oxide film by DC magnetron sputtering. The preparation method of this embodiment is the same as that of Example 1, except that after the oxide film is obtained in the coating step, the obtained oxide film is placed on a hot plate at 180° C. and annealed in an atmospheric environment for 30 minutes to obtain a high-mobility transparent conductive oxide film.

[0070] Example 5

[0071] A method for preparing a high-mobility transparent conductive oxide film by DC magnetron sputtering. The preparation method of this embodiment is the same as that of Example 1, except that after the oxide film is obtained in the coating step, the obtained oxide film is placed on a hot plate at 185° C. and annealed for 30 minutes in an atmospheric environment to obtain a high-mobility transparent conductive oxide film.

[0072] Example 6

[0073] A method for preparing a high-mobility transparent conductive oxide film by DC magnetron sputtering. The preparation method of this embodiment is the same as that of Example 1, except that after the oxide film is obtained in the coating step, the obtained oxide film is placed on a hot plate at 190° C. and annealed in an atmospheric environment for 30 minutes to obtain a high-mobility transparent conductive oxide film.

[0074] Example 7

[0075] A method for preparing a high-mobility transparent conductive oxide film by DC magnetron sputtering. The preparation method of this embodiment is the same as that of Example 1, except that after the oxide film is obtained in the coating step, the obtained oxide film is placed on a hot plate at 195° C. and annealed for 30 minutes in an atmospheric environment to obtain a high-mobility transparent conductive oxide film.

[0076] Example 8

[0077] A method for preparing a high-mobility transparent conductive oxide film by DC magnetron sputtering. The preparation method of this embodiment is the same as that of Example 1, except that after the oxide film is obtained in the coating step, the obtained oxide film is placed on a hot plate at 200° C. and annealed for 30 minutes in an atmospheric environment to obtain a high-mobility transparent conductive oxide film.

[0078] Example 9

[0079] A method for preparing a high-mobility transparent conductive oxide film by DC magnetron sputtering. The preparation method of this embodiment is the same as that of Example 1, except that in the coating step, the sputtering power is set to 900 W. After the oxide film is obtained in the coating step, the obtained oxide film is placed on a hot plate at 200° C. and annealed in an atmospheric environment for 30 minutes to obtain a high-mobility transparent conductive oxide film.

[0080] Example 10

[0081] A method for preparing a high-mobility transparent conductive oxide film by DC magnetron sputtering. The preparation method of this embodiment is the same as that of Example 1, except that in the coating step, the oxygen flow rate is set to 10 sccm. After the oxide film is obtained in the coating step, the obtained oxide film is placed on a hot plate at 200°C and annealed in an atmospheric environment for 30 minutes to obtain a high-mobility transparent conductive oxide film.

[0082] Embodiment 11

[0083] A method for preparing a high-mobility transparent conductive oxide film by direct current magnetron sputtering. The preparation method of this embodiment is the same as that of embodiment 1, except that in the coating step, the oxygen flow rate is set to 15 sccm. After the oxide film is obtained in the coating step, the obtained oxide film is placed on a hot plate at 200° C. and annealed in an atmospheric environment for 30 minutes to obtain a high-mobility transparent conductive oxide film.

[0084] Comparative Example 1

[0085] Comparative Example 1: 90:10 ITO target material was selected, and indium oxide spherical powder was prepared by chemical precipitation method. The average particle size of indium oxide spherical powder was D90=300nm, and the average particle size of tin oxide powder was D90=150nm. Indium oxide and tin oxide powder were weighed according to the mass ratio of 90wt% and 10wt%, and stirred and mixed to obtain the first powder.

[0086] Then pour the first powder into a sand mill, add dispersant deionized water and 5% ethanol, the solid content is 63%, and further sand grind for 1 hour to obtain the first slurry.

[0087] Add 1 wt.% of polyvinyl alcohol as a binder to the first slurry, grind for 1 hour to obtain a second slurry.

[0088] The second slurry is used for spray granulation, the air inlet temperature is 190-210°C, the exhaust air temperature is 96-104°C, and the first dry powder is obtained.

[0089] The first dry powder is subjected to cyclone separation to obtain a second dry powder with a particle size of D90 = 106 ± 20 nm.

[0090] The second dry powder is loaded into the rubber mold for filling, and ultrasonic assistance is used to increase the tap density of the second dry powder in the mold, and the mold is pressed in a cold isostatic press. The pressure is set to 28 MPa and maintained for 30 minutes, then adjusted to 300 MPa and maintained for 2 hours, and then the pressure is gradually reduced by a gradient of 15 MPa to release the internal stress to obtain a green body.

[0091] The green body was placed in a sintering furnace for high-temperature sintering. 977 sccm of air and 29 sccm of oxygen were introduced. The sintering furnace was controlled to increase the temperature from room temperature to 650°C at a gradient of 4°C / min and keep it at that temperature for 2 hours. Then the temperature was increased to 1520°C at a gradient of 6°C / min and kept at that temperature for 210 hours. Then the temperature was reduced to room temperature at a corresponding rate.

[0092] Then the target material is machined and bound according to the corresponding drawings to obtain the ITO target material;

[0093] The coating step includes installing the high-mobility sputtering target on a DC magnetron sputtering coating machine, sputtering the oxide film by the DC magnetron sputtering coating machine, and controlling the film thickness of the oxide film to be 98 nm. The obtained oxide film is placed on a hot plate at 200° C. and annealed in an atmospheric environment for 30 minutes to obtain a high-mobility transparent conductive oxide film.

[0094] During the sputtering coating process, the background vacuum of the DC magnetron sputtering coating machine was controlled to be less than 9E-4Pa, the sputtering power was 1200W, the argon flow rate was 100sccm, the oxygen flow rate was 20sccm, the chamber temperature was 27°C, and the sputtering time was 308s.

[0095] The square resistance of the 90:10 ITO film of comparative example 1 and each high-mobility transparent conductive oxide film prepared in each embodiment was tested by a four-probe instrument. In addition, the carrier concentration and Hall mobility parameters of the film were tested by a Hall test system, and the thickness of the film was tested by an ellipsometer to obtain a parameter comparison table, as shown in Table 1.

[0096]

[0097] Table 1 - Parameter comparison table.

Claims

1. A method for preparing a high-mobility transparent conductive oxide film by direct current magnetron sputtering, characterized in that: The following steps are included: Target preparation steps: Indium oxide powders in the shapes of a sphere, a pyramid and a football are mixed to obtain indium oxide powder, wherein the mass proportion of the indium oxide powders in the shapes of a pyramid and a football in the total indium oxide powder is greater than 20%, the contact between the indium oxide powder in the shape of a football and other powders is surface-to-surface contact, and the contact between the indium oxide powder in the shape of a sphere and other powders is point contact; According to the mass percentage, 95-99.4wt% of indium oxide powder and 0.1-4.8wt% of tin oxide powder are first mixed evenly, and then 0.1-0.3wt% of yttrium oxide powder and 0.1-0.4wt% of antimony oxide powder and the rest of tellurium oxide powder are added in sequence, and stirred and mixed evenly to obtain a first powder. Then pour the first powder into a sand mill, add dispersant deionized water and 10±5% ethanol, control the solid content at 55±5%, and further sand grind for 1h±0.5 to obtain the first slurry. Add the binder polyvinyl alcohol to the first slurry, the content is 0.5±0.2wt.%, grind for 1±0.5h to obtain the second slurry, The second slurry is used for spray granulation, the air inlet temperature is 200±50℃, the exhaust temperature is 90±10℃, and the first dry powder is obtained. The first dry powder is subjected to cyclone separation to obtain a second dry powder with a particle size of D90 = 300 ± 50 nm. The second dry powder is loaded into the rubber mold for filling, and ultrasonic assistance is used to increase the tap density of the second dry powder in the mold, and the mold is pressed by cold isostatic pressing. The pressure is set to 30±5MPa and maintained for 30±5min, then adjusted to 280±20MPa and maintained for 2±0.5h, and then the pressure is gradually reduced by a gradient of 10±2MPa to release the internal stress to obtain a green body. Place the green body into a sintering furnace for high-temperature sintering, introduce 900-1000sccm of air and 20-35sccm of oxygen, control the sintering furnace to heat up to 650±10℃ at a gradient of 0.5±0.1℃ / min, and keep it warm for 3±1h; then heat up to 1500-1600℃ at a gradient of 1±0.2℃ / min, keep it warm for 250±20h, and then reduce the temperature to room temperature at a corresponding rate. Then the target material is machined and bound according to the corresponding drawings to obtain a high-mobility sputtering target material; In the coating step, a high-mobility sputtering target is installed on a DC magnetron sputtering coating machine, and an oxide film is obtained by sputtering coating with the DC magnetron sputtering coating machine, and the film thickness of the oxide film is controlled to be 100±10nm, and the obtained oxide film is annealed at different temperatures in an atmospheric environment for 30±5min to obtain a high-mobility transparent conductive oxide film.

2. The method for preparing a high-mobility transparent conductive oxide thin film by direct current magnetron sputtering according to claim 1, characterized in that: In the step of preparing the target material, according to the mass percentage, firstly, 99wt% of the indium oxide powder and 0.5wt% of the tin oxide powder are evenly mixed, and then 0.2wt% of the yttrium oxide powder, 0.2wt% of the antimony oxide powder and 0.1wt% of the tellurium oxide powder are added in sequence, and the mixture is evenly mixed.

3. The method for preparing a high-mobility transparent conductive oxide thin film by direct current magnetron sputtering according to claim 1, characterized in that: In the target material preparation step, the mass proportion of the indium oxide powder in the shape of a pyramid and a football in the total indium oxide powder is 20-40%.

4. The method for preparing a high-mobility transparent conductive oxide thin film by direct current magnetron sputtering according to claim 1, characterized in that: In the target material preparation step, the average particle size of the indium oxide powder is D90=300±20nm, and the average particle size of the tin oxide powder is D90=150±20nm; the mass proportion of the indium oxide powder in the shape of a pyramid and a football in the total indium oxide powder is 20-25%.

5. The method for preparing a high-mobility transparent conductive oxide thin film by direct current magnetron sputtering according to claim 1, characterized in that: In the step of preparing the target material, a chemical precipitation method is used to prepare the indium oxide powder in the shape of a football. The indium oxide powder in the shape of a football is a polyhedral structure formed by a plurality of adjacent polygonal platforms.

6. The method for preparing a high-mobility transparent conductive oxide thin film by direct current magnetron sputtering according to claim 5, characterized in that: In the target material preparation step, a plurality of polygonal deposition platforms of the same shape and successively decreasing side lengths are deposited and stacked on top of each of the polygonal platforms on the surface of the football-shaped indium oxide powder, and the top surface of the uppermost polygonal deposition platform is a plane.

7. The method for preparing a high-mobility transparent conductive oxide thin film by direct current magnetron sputtering according to claim 6, characterized in that: In the target material preparation step, the football-shaped indium oxide powder has a polyhedral structure whose surface is formed by adjacently splicing a plurality of quadrilateral tables, a plurality of pentagonal tables and a plurality of hexagonal tables.

8. The method for preparing a high-mobility transparent conductive oxide thin film by direct current magnetron sputtering according to claim 1, characterized in that: The step of preparing the target material, The first powder is poured into the sand mill, and the dispersant deionized water and 10% of the ethanol are added, and the solid content is controlled at 55%, and further sand milled for 1 hour to obtain the first slurry. Add the binder polyvinyl alcohol (content 0.5 wt.%) to the first slurry, grind for 1 hour to obtain the second slurry, The spray granulation is performed using the second slurry, the air inlet temperature is 200-220° C., the exhaust air temperature is 85-90° C., to obtain the first dry powder, The first dry powder is subjected to cyclone separation to obtain the second dry powder with a particle size of D90=300±20 nm, The second dry powder is loaded into the rubber mold, and the second dry powder is filled. Ultrasonic wave assist is used to increase the tap density of the second dry powder in the mold, and the mold is pressed by cold isostatic pressing. The pressure is set to 30 MPa and maintained for 30 minutes, then adjusted to 280 MPa and maintained for 2 hours, and then the pressure is gradually reduced by a gradient of 10 MPa to release the internal stress, thereby obtaining the green body. The green body was placed in a sintering furnace for high-temperature sintering, 977 sccm of air and 29 sccm of oxygen were introduced, and the sintering furnace was controlled to increase the temperature to 650°C at a gradient of 0.5°C / min and keep it at that temperature for 3 hours; then the temperature was increased to 1560°C at a gradient of 1°C / min and kept at that temperature for 250 hours, and then the temperature was reduced to room temperature at a corresponding rate.

9. The method for preparing a high-mobility transparent conductive oxide thin film by direct current magnetron sputtering according to any one of claims 1 to 8, characterized in that: The coating step, During the sputtering coating process, the background vacuum of the DC magnetron sputtering coating machine is controlled to be higher than 2× 10 -3 Pa, set the sputtering pressure to 0.1-2Pa, the sputtering voltage to 200-500V, the sputtering current to 5-20A, the oxygen / argon partial pressure to 1-10%, and the hydrogen / argon partial pressure to 0-2.8%, For planar targets, the sputtering power density is controlled at 0.2-10 W / cm 2 For rotating targets, the sputtering power density is controlled at 2-15kw / m.

10. The method for preparing a high-mobility transparent conductive oxide thin film by direct current magnetron sputtering according to claim 9, characterized in that: The high-mobility transparent conductive oxide film was placed on a hot plate at 170-200° C. and annealed in an atmospheric environment for 30 minutes.

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