ICO target material for reactive plasma deposition coating and preparation method thereof

Abstract

The present invention provides an ICO target material for reactive plasma deposition coating and a preparation method thereof, belonging to the technical field of target material preparation. The ICO target material comprises oxides of In, Ce and X, wherein the atomic ratio of In, Ce and X is (95-99) / (1-5) / (0.001-0.5); wherein X is selected from at least one of the lanthanide rare earth elements other than Ce; the ICO target material has a loose porous structure, and a relative density of 55-65%. The ICO target material of the present invention can significantly improve the mobility and average transmittance of a transparent conductive oxide film prepared by the ICO target material by co-doping cerium and other lanthanide rare earth elements. Therefore, the ICO target material provided by the present invention can have both good light transmittance and high electrical conductivity.

Description

Technical Field

[0001] The invention belongs to the technical field of target material preparation, and in particular relates to an ICO target material for reactive plasma deposition coating and a preparation method thereof. Background Art

[0002] The coating methods of TCO thin films (transparent conductive oxide) mainly include magnetron sputtering, thermal / electron beam evaporation and reactive plasma deposition (RPD). RPD has the advantages of high target utilization, less damage to the substrate, low-temperature coating, dense film, and good comprehensive optoelectronic performance, so it has gradually been widely studied and applied. However, compared with other coating methods, RPD has higher requirements on the density of the target material. If the density is too high (such as the target material used for magnetron sputtering), it is easy to cause the target material to crack. If the density is too low, it is easy to cause the target material to splash dust or collapse, thus making it impossible to obtain high-quality thin films. Therefore, controlling the density of the target material within an appropriate range plays a key role in the preparation of high-quality TCO thin films.

[0003] At present, TCO thin film systems include ITO (Sn doped In2O3), AZO (Al doped ZnO), FTO (F doped SnO2) and IMO (Mo doped In2O3). Among them, ITO has the best comprehensive photoelectric performance and is widely used in flat display devices and thin-film solar cells. However, although Sn doping can increase the carrier concentration, the carrier mobility and near-infrared transmittance are low, making it difficult to have both excellent conductivity and light transmittance, and its development space is limited.

[0004] Therefore, it is necessary to develop an ICO target material for reactive plasma deposition coating that can replace ITO, so that the ICO film formed by coating can have both excellent electrical conductivity and light transmittance. Summary of the invention

[0005] The object of the present invention is to provide an ICO target material for reactive plasma deposition coating and a preparation method thereof, aiming to solve the problem that the existing ITO target material for preparing TCO thin films cannot simultaneously take into account excellent conductivity and light transmittance.

[0006] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is as follows:

[0007] In a first aspect, the present invention provides an ICO target for reactive plasma deposition coating, comprising oxides of In, Ce and X, wherein the atomic ratio of In, Ce and X is (95-99) / (1-5) / (0.001-0.5);

[0008] Wherein, the X is selected from at least one of the lanthanide rare earth elements except Ce;

[0009] The ICO target material has a loose porous structure and a relative density of 55-65%.

[0010] In a second aspect, the present invention provides a method for preparing an ICO target material for reactive plasma deposition coating, comprising the following steps:

[0011] preparing X-doped indium oxide powder and indium cerium oxide powder respectively;

[0012] The cerium indium oxide powder and the X-doped indium oxide powder are uniformly mixed to obtain a mixed powder;

[0013] Molding the mixed powder to obtain a target blank;

[0014] The target material blank is sintered at high temperature to obtain an ICO target material.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The ICO target material for reactive plasma deposition coating provided by the present invention, on the one hand, contains cerium as the main dopant, because Ce 4+ The ionic radius (87 pm) is smaller than Sn 4+ The ionic radius (69 pm) is closer to In 3+ Ionic radius (80 pm), so Ce 4+ Replacement of Sn 4+ When In2O3 is doped, the lattice distortion is smaller, which can reduce the defects caused by the accumulation of lattice distortion, which is beneficial to reduce the carrier defect scattering caused by structural mismatch and improve the carrier mobility; and Ce 4+ Doping can also reduce the oxygen vacancy density, which is beneficial to improve the relaxation time and mobility of carriers. Therefore, the coating of ICO target doped with cerium has better conductivity than that of indium oxide (ITO) target doped with tin. On the other hand, it also contains lanthanide rare earth elements other than Ce as auxiliary dopants, lanthanide rare earth ions such as Sm 3+ ,La 3+ 、Lu 3+The ICO target has a lower electronegativity, a stronger ability to bond with oxygen ions, and the formed ionic bonds have a higher bond energy, are not easy to break, and can reduce the escape of oxygen atoms, thereby further reducing oxygen vacancies, improving carrier mobility and material stability; and, by doping with these lanthanide rare earth elements other than Ce, the Fermi level of ICO can be adjusted, the work function of ICO can be changed, and the ohmic contact between ICO and functional layers such as gate lines and Si can be effectively improved. In addition, the ICO target has a loose porous structure and a relative density of 55 to 65%, so that the ICO target of the present invention is suitable for reactive plasma deposition coating, so the target has a higher utilization rate, and low-temperature coating can be used to make the obtained X-doped TCO film denser and better in photoelectric performance. Therefore, the ICO target provided by the present invention can have both good light transmittance and high electrical conductivity.

[0017] The preparation method of the ICO target material for reactive plasma deposition coating provided by the present invention comprises the following steps: firstly preparing X-doped indium oxide powder as the first component, and indium oxide cerium powder as the second component, and then mixing and granulating the X-doped indium oxide powder and indium oxide cerium powder. Compared with the conventional preparation method of directly ball-milling and mixing indium oxide powder, cerium oxide powder and X oxide powder, the present invention can fill the X-doped indium oxide powder into the gap of indium oxide cerium powder, which is conducive to uniform mixing, and can effectively prevent the formation of multiple intermediate compounds and equal segregation during the sintering process, so that the uniformity of the ICO target material structure can be greatly improved, so that the obtained ICO target material coating has higher mobility and average transmittance, and can effectively prevent the target material from generating color difference and cracking during coating, etc. In addition, the X-doped indium oxide powder as the first component has higher sintering activity, so it is conducive to shortening the chemical migration during the sintering process, shortening the sintering time, and reducing energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope of the present invention.

[0019] Figure 1 This is a cross-sectional microscopic morphology of the ICO target material of Example 1 of the present invention;

[0020] Figure 2 This is a photo of the finished target material of Example 1 of the present invention. DETAILED DESCRIPTION

[0021] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0022] In the present invention, the term "and / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone.

[0023] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0024] The terms "first" and "second" are used only for descriptive purposes to distinguish objects such as substances from each other, and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. For example, without departing from the scope of the embodiments of the present invention, the first XX may also be referred to as the second XX, and similarly, the second XX may also be referred to as the first XX. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0025] If no specific conditions are specified in the examples of the present invention, the experiments were carried out under conventional conditions or conditions recommended by the manufacturer. If no manufacturer is specified for the materials or instruments used, they are all conventional products that can be purchased commercially.

[0026] The inventors of the present invention discovered during the research process that since the transmittance and conductivity of the TCO film directly affect the conversion efficiency of the solar cell, if the TCO layer is to have good transmittance, especially transmittance in the infrared region, it is first necessary to control the concentration of carriers. On this basis, in order to improve the conductivity of the TCO layer, it is necessary to increase the mobility of carriers, which can be achieved, for example, by reducing crystal defects, increasing grain size, and selecting materials with smaller electron effective mass.

[0027] A first aspect of an embodiment of the present invention provides an ICO target material for reactive plasma deposition coating, comprising oxides of In, Ce and X, wherein the atomic ratio of In, Ce and X is (95-99) / (1-5) / (0.001-0.5);

[0028] Wherein, X is selected from at least one of the lanthanide rare earth elements except Ce;

[0029] The ICO target material has a loose porous structure and a relative density of 55-65%.

[0030] The ICO target material for reactive plasma deposition coating provided in the embodiment of the present invention, on the one hand, contains cerium as the main dopant. 4+ The ionic radius (87 pm) is smaller than Sn 4+The ionic radius (69 pm) is closer to In 3+ Ionic radius (80 pm), so Ce 4+ Replacement of Sn 4+ When In2O3 is doped, the lattice distortion is smaller, which can reduce the defects caused by the accumulation of lattice distortion, which is beneficial to reduce the carrier defect scattering caused by structural mismatch and improve the carrier mobility; and Ce 4+ Doping can also reduce the oxygen vacancy density, which is beneficial to improve the relaxation time and mobility of carriers. Therefore, the coating of ICO target doped with cerium has better conductivity than that of indium oxide (ITO) target doped with tin. On the other hand, it also contains lanthanide rare earth elements other than Ce as auxiliary dopants, lanthanide rare earth ions such as Sm 3+ ,La 3+ 、Lu 3+ The ICO target has a lower electronegativity, a stronger ability to bond with oxygen ions, and the formed ionic bonds have a higher bond energy, are not easy to break, and can reduce the escape of oxygen atoms, thereby further reducing oxygen vacancies, improving carrier mobility and material stability; and, by doping with these lanthanide rare earth elements other than Ce, the Fermi level of ICO can be adjusted, the work function of ICO can be changed, and the ohmic contact between ICO and functional layers such as gate lines and Si can be effectively improved. In addition, the ICO target has a loose porous structure and a relative density of 55 to 65%, so that the ICO target of the present invention is suitable for reactive plasma deposition coating, so the target has a higher utilization rate, and low-temperature coating can be used to make the obtained X-doped TCO film denser and better in photoelectric performance. Therefore, the ICO target provided by the present invention can have both good light transmittance and high electrical conductivity.

[0031] In some embodiments, X is selected from at least one of La, Sm, Pr, Tb, Gd, and Lu. These elements have lower electronegativity, stronger bonding ability with oxygen ions, and the formed ionic bonds have higher bond energy, are not easy to break, and can reduce the escape of oxygen atoms, thereby further reducing oxygen vacancies, improving carrier mobility and material stability. In addition, the Fermi level of ICO can be adjusted, the work function of ICO can be changed, and the ohmic contact between ICO and functional layers such as gate lines and Si can be effectively improved.

[0032] In some embodiments, X includes a first lanthanide rare earth element and a second lanthanide rare earth element in an atomic ratio of (0.0005-0.3) / (0.0005-0.2); wherein the first lanthanide rare earth element is selected from at least one of La and Sm, and the second lanthanide rare earth element is selected from at least one of Pr, Tb, Gd, and Lu. In one aspect, the valence electron layer structure of La is arranged as 4f 0 5d 1 6s 2, with a full 4f orbital, the valence electron structure of Sm is arranged as 4f 6 6s 2 , has a nearly half-full 4f orbital, so the first lanthanide rare earth element of the specific content of this embodiment is added as an auxiliary dopant, and the energy of the 4f electron orbit of La and Sm increases after electron transfer with the 5s electron orbit of In, which can block the electron transfer path and reduce the recombination probability of photogenerated carriers, thereby improving the carrier mobility. On the other hand, a second lanthanide rare earth element with lower electronegativity is also added, which has a stronger bonding ability with oxygen ions, so that the bond energy of the formed ionic bond is higher, not easy to break, and can reduce the escape of oxygen atoms and reduce oxygen vacancies, thereby further improving the carrier mobility. Therefore, this embodiment can significantly improve the mobility of the transparent conductive oxide film prepared by the ICO target material of the present invention by adding a specific proportion of the first lanthanide rare earth element and the second lanthanide rare earth element for compounding, so that both excellent conductivity and light transmittance can be taken into account.

[0033] The second aspect of the embodiment of the present invention provides a method for preparing an ICO target material for reactive plasma deposition coating, comprising the following steps:

[0034] S01: preparing X-doped indium oxide powder and indium cerium oxide powder respectively;

[0035] S02: mixing the indium cerium oxide powder and the X-doped indium oxide powder uniformly to obtain a mixed powder;

[0036] S03: forming the mixed powder to obtain a target blank;

[0037] S04: Sintering the target blank at high temperature to obtain an ICO target.

[0038] The preparation method of the ICO target material for reactive plasma deposition coating provided by the embodiment of the present invention is to first prepare X-doped indium oxide powder as the first component, indium oxide cerium powder as the second component, and then mix and granulate the X-doped indium oxide powder and indium oxide cerium powder. Compared with the traditional preparation method of directly ball-milling and mixing indium oxide powder, cerium oxide powder and X oxide powder, the present invention can fill the X-doped indium oxide powder into the gap of indium oxide cerium powder, which is conducive to uniform mixing, and can effectively prevent the formation of multiple intermediate compounds during the sintering process, and the segregation is equal, so that the uniformity of the ICO target material organization can be greatly improved, so that the prepared ICO target material coating has a higher mobility and average transmittance, and can effectively prevent the target material from having color difference and cracking during coating. In addition, the X-doped indium oxide powder as the first component has a higher sintering activity, so it is conducive to shortening the chemical migration during the sintering process, shortening the sintering time, and reducing energy consumption.

[0039] In the above step S01, the step of preparing X-doped indium oxide powder includes: dissolving indium salt, X salt and precipitant in a solvent to form a mixed solution; transferring the mixed solution to a reactor, performing a hydrothermal reaction treatment, and then sequentially performing solid-liquid separation, washing, drying and a first calcination treatment to obtain X-doped indium oxide powder. Compared with the traditional solid phase reaction method of directly mixing lanthanide rare earth oxide powder and indium oxide powder by ball milling, granulating and then sintering at high temperature, the embodiment of the present invention adopts a hydrothermal reaction method, which can accurately control the stoichiometric ratio of In and X, so that the formed In 2-x X x The O3 solid solution has a precise ratio and can also promote the reaction and shorten the reaction time. By controlling the reaction temperature, pressure and time, the morphology of the powder can be controlled to make the powder of appropriate size and good uniformity, which is conducive to sintering with the second component of indium cerium oxide powder to form a uniform ICO target material, thereby preventing the segregation of lanthanide rare earth elements; in addition, it can also avoid the volatilization of lanthanide rare earth elements caused by high-temperature solid-phase reaction and improve the utilization rate of lanthanide rare earth raw materials.

[0040] In the embodiment, the temperature of the hydrothermal reaction treatment is 150-250° C., and the time is 12-24 hours.

[0041] In the embodiment, the temperature of the first calcination treatment is 400-800° C., and may further be 400-600° C., and the time is 6-10 hours, and may further be 2-4 hours.

[0042] In an embodiment, the indium salt is selected from indium chloride or indium nitrate; the cerium salt is selected from any one of cerium chloride, cerium nitrate, and cerium sulfate; the X salt is selected from chloride of X or nitrate of X, such as lanthanum chloride, samarium nitrate, praseodymium chloride, terbium chloride, gadolinium chloride, lutetium chloride, etc. The precipitant is selected from urea.

[0043] In the embodiment, the purity of the X-doped indium oxide powder is made ≥ 99.99% by washing.

[0044] In an embodiment, the step of preparing indium oxide cerium powder may include: adding indium oxide powder and cerium oxide powder to pure water, then adding a dispersant, a binder and a defoamer to ball mill and mix, and then spray granulation to obtain granulated powder; the granulated powder is subjected to a second calcination treatment to obtain indium oxide cerium powder. Among them, the purity of indium oxide powder is ≥99.99%, and the purity of cerium oxide powder is ≥99.99%. The dispersant can be selected from one or more of polyethylene glycol, hexadecyl sulfonate, polycarboxylate, polyacrylic acid salt or triethanolamine. The binder can be selected from one or more of polyvinyl alcohol, polypropylene resin, polyacrylamide or gelatin. The defoamer can be selected from polyether defoamers and / or high carbon alcohols. The inlet temperature of the spray granulation is 180-220°C, and the outlet temperature is 80-100°C. The temperature of the second calcination treatment is 1000-1500°C, and the time is 6-10h.

[0045] In the embodiment, the specific surface area of ​​the X-doped indium oxide powder is 10 to 30 m 2 / g, and can further be 15 to 20 m 2 / g; the specific surface area of ​​indium cerium oxide powder is 0.1~3.0m 2 / g, and can further be 1 to 2 m 2 / g; the mass ratio of X-doped indium oxide powder to indium cerium oxide powder is (20-40) / (60-80). Within the specific surface area and mass ratio range of the X-doped indium oxide powder and indium cerium oxide powder, it is beneficial for the X-doped indium oxide powder to fill the voids of the indium cerium oxide powder, which can assist in molding. At the same time, it has higher sintering activity, can improve the sintering and diffusion efficiency of the first component of the X-doped indium oxide powder and the second component of the indium cerium oxide powder, reduce the generation of large pores and the total number of pores, and improve the organizational uniformity and density of the ICO target material, thereby facilitating the improvement of the mobility and average transmittance of the target coating. Avoid too large a specific surface area, too fine a powder, and too large an elastic aftereffect of the press molding, which may cause the ICO target material to be easily delaminated or cracked. It is also avoided that the specific surface area is too small, the powder is too large, the required sintering temperature is high, and it is difficult to achieve sintering, resulting in poor solid solution, uneven distribution of components, and poor densification, and thus poor film properties.

[0046] In the above step S03, the forming may include: performing cold isostatic pressing at a pressure of 50-200 MPa.

[0047] In the above step S04, the high temperature sintering atmosphere is oxygen, the pressure is 0.05-0.10 MPa, the temperature is 1000-1550°C, and can be further 1200-1400°C, and the time is 8-36 hours. In this sintering temperature range, the mobility, resistivity, relative density, etc. are all optimal.

[0048] After high temperature sintering and machining, the standard size of the ICO target product is

[0049] The following describes the invention in conjunction with specific embodiments.

[0050] Example 1

[0051] This embodiment provides an ICO target material for reactive plasma deposition coating and a preparation method thereof.

[0052] The method for preparing an ICO target material for reactive plasma deposition coating comprises the following steps:

[0053] S1: According to the atomic ratio of In and Sm of 29.04 / 0.2, weigh appropriate amounts of indium chloride and samarium nitrate; dissolve indium chloride and samarium nitrate in water, then add urea and mix evenly, so that the pH of the reaction system is 9 to form a mixed solution; transfer the mixed solution to the inner tank of the reactor, and add appropriate amount of deionized water so that the final volume of the mixed solution is 70% of the volume of the inner tank of the reactor, put the reactor into a drying oven at 200°C for hydrothermal reaction for 12 hours, and then use deionized water and anhydrous ethanol to repeatedly wash the precipitate obtained by centrifugation, and after drying, calcine in a muffle furnace at 600°C for 8 hours to obtain a precipitate with a purity of ≥99.99% and a specific surface area of ​​15.3m 2 / g of samarium-doped indium oxide powder (In 2-x Sm x O3);

[0054] S2: According to the atomic ratio of In and Ce of 67.76 / 3, appropriate amounts of indium oxide powder and cerium oxide powder with a purity of ≥99.99% were weighed and added into pure water, and then hexadecyl sulfonate, gelatin, and polyoxypropylene glycerol ether were added and ball-milled for 10 hours. The total solid content was controlled at about 65%, and the mixed slurry obtained by ball milling was introduced into a centrifugal spray granulator with an inlet temperature of 180°C and an outlet temperature of 80°C to obtain granulated powder; the granulated powder was calcined at 1350°C for 8 hours to obtain a specific surface area of ​​1.2 m 2 / g of indium cerium oxide powder;

[0055] S3: according to the mass ratio of samarium-doped indium oxide powder to indium-cerium oxide powder being 30 / 70, appropriate amounts of samarium-doped indium oxide powder and indium-cerium oxide powder are weighed and mixed evenly to obtain a mixed powder;

[0056] S4: The mixed powder is loaded into a stainless steel mold, preformed with a hydraulic press, and then cold isostatically pressed at a pressure of 100 MPa to obtain a target blank;

[0057] S5: The target blank is sintered at a high temperature of 1350° C. for 36 hours in an oxygen atmosphere with a pressure of 0.05 MPa, and after machining, a samarium-doped indium cerium oxide target of standard size is obtained.

[0058] It has been detected that the samarium-doped indium cerium oxide target contains In, Ce, and Sm in an atomic ratio of 96.8 / 3 / 0.2, and has a loose porous structure with an average relative density of 60.5%.

[0059] Example 2

[0060] This embodiment provides an ICO target material for reactive plasma deposition coating and a preparation method thereof.

[0061] The method for preparing an ICO target material for reactive plasma deposition coating comprises the following steps:

[0062] S1: According to the atomic ratio of In and Tb of 29.04 / 0.2, weigh appropriate amounts of indium chloride and terbium nitrate; dissolve indium chloride and terbium nitrate in water, then add urea and mix evenly, so that the pH of the reaction system is 9 to form a mixed solution; transfer the mixed solution to the inner tank of the reactor, and add appropriate amount of deionized water so that the final volume of the mixed solution is 70% of the volume of the inner tank of the reactor, put the reactor into a drying oven at 200°C for hydrothermal reaction for 12 hours, and then use deionized water and anhydrous ethanol to repeatedly wash the precipitate obtained by centrifugation, and after drying, calcine in a muffle furnace at 600°C for 8 hours to obtain a precipitate with a purity of ≥99.99% and a specific surface area of ​​15.6m 2 / g of terbium-doped indium oxide powder (In 2-x Tb x O3);

[0063] S2: According to the atomic ratio of In and Ce of 67.76 / 3, appropriate amounts of indium oxide powder and cerium oxide powder with a purity of ≥99.99% were weighed and added into pure water, and then hexadecyl sulfonate, gelatin, and polyoxypropylene glycerol ether were added and ball-milled for 10 hours. The total solid content was controlled at about 65%, and the mixed slurry obtained by ball milling was introduced into a centrifugal spray granulator with an inlet temperature of 180°C and an outlet temperature of 80°C to obtain granulated powder; the granulated powder was calcined at 1350°C for 8 hours to obtain a specific surface area of ​​1.2 m 2 / g of indium cerium oxide powder;

[0064] S3: according to the mass ratio of samarium-doped indium oxide powder to indium-cerium oxide powder of 30 / 70, appropriate amounts of terbium-doped indium oxide powder and indium-cerium oxide powder are weighed and mixed evenly to obtain a mixed powder;

[0065] S4: The mixed powder is loaded into a stainless steel mold, preformed with a hydraulic press, and then cold isostatically pressed at a pressure of 100 MPa to obtain a target blank;

[0066] S5: The target blank is sintered at a high temperature of 1350° C. for 36 hours in an oxygen atmosphere with a pressure of 0.05 MPa, and after machining, a standard-sized terbium-doped indium cerium oxide target is obtained.

[0067] It has been detected that the terbium-doped indium cerium oxide target contains In, Ce, and Tb in an atomic ratio of 96.8 / 3 / 0.2, and has a loose porous structure with an average relative density of 60.7%.

[0068] Example 3

[0069] The method for preparing an ICO target material for reactive plasma deposition coating comprises the following steps:

[0070] S1: According to the atomic ratio of In, Sm, and Tb of 29.04 / 0.1 / 0.1, appropriate amounts of indium chloride, samarium nitrate, and terbium chloride are weighed; indium chloride, samarium nitrate, and terbium chloride are dissolved in water, and then urea is added and mixed evenly to make the pH of the reaction system 9 to form a mixed solution; the mixed solution is transferred to the inner tank of the reactor, and an appropriate amount of deionized water is added to make the final volume of the mixed solution 70% of the volume of the inner tank of the reactor, and the reactor is placed in a drying oven at 200°C for hydrothermal reaction for 12 hours, and then the precipitate obtained by centrifugation is repeatedly washed with deionized water and anhydrous ethanol, respectively, and after drying, it is calcined in a muffle furnace at 600°C for 8 hours to obtain a precipitate with a purity of ≥99.99% and a specific surface area of ​​15.2m 2 / g of indium oxide powder doped with samarium and terbium (In 2- x Sm x O3);

[0071] S2: According to the atomic ratio of In and Ce of 67.76 / 3, appropriate amounts of indium oxide powder and cerium oxide powder with a purity of ≥99.99% were weighed and added into pure water, and then hexadecyl sulfonate, gelatin, and polyoxypropylene glycerol ether were added and ball-milled for 10 hours. The total solid content was controlled at about 65%, and the mixed slurry obtained by ball milling was introduced into a centrifugal spray granulator with an inlet temperature of 180°C and an outlet temperature of 80°C to obtain granulated powder; the granulated powder was calcined at 1350°C for 8 hours to obtain a specific surface area of ​​1.2 m 2 / g of indium cerium oxide powder;

[0072] S3: according to the mass ratio of samarium terbium doped indium oxide powder and indium cerium oxide powder being 30 / 70, weigh appropriate amounts of samarium terbium doped indium oxide powder and indium cerium oxide powder and mix them evenly to obtain a mixed powder;

[0073] S4: The mixed powder is loaded into a stainless steel mold, preformed with a hydraulic press, and then cold isostatically pressed at a pressure of 100 MPa to obtain a target blank;

[0074] S5: The target blank is sintered at a high temperature of 1350° C. for 36 hours in an oxygen atmosphere with a pressure of 0.05 MPa, and after machining, a standard-sized samarium-terbium-doped indium-cerium oxide target is obtained.

[0075] It has been detected that the samarium-terbium-doped indium-cerium oxide target contains In, Ce, Sm, and Tb in an atomic ratio of 96.8 / 3 / 0.1 / 0.1, and has a loose porous structure with an average relative density of 60.2%.

[0076] Example 4

[0077] This embodiment provides an ICO target material for reactive plasma deposition coating and a preparation method thereof, which is different from Embodiment 1 in that:

[0078] In step S1, calcination is performed in a muffle furnace at 800°C for 10 hours to obtain a product with a purity of ≥99.99% and a specific surface area of ​​10.7 m 2 / g of samarium-doped indium oxide powder;

[0079] In step S2, the granulated powder is calcined at 1500°C for 10 hours to obtain a specific surface area of ​​0.1 m 2 / g of indium cerium oxide powder;

[0080] In step S5, the sintering temperature is 1450°C.

[0081] It has been detected that the samarium-doped indium cerium oxide target contains In, Ce, and Sm in an atomic ratio of 96.8 / 3 / 0.2, and has a loose porous structure with an average relative density of 63.5%.

[0082] Example 5

[0083] This embodiment provides an ICO target material for reactive plasma deposition coating and a preparation method thereof, which is different from Embodiment 1 in that:

[0084] In step S1, calcination is performed in a muffle furnace at 800°C for 10 hours to obtain a product with a purity of ≥99.99% and a specific surface area of ​​10.7 m 2 / g of samarium-doped indium oxide powder;

[0085] In step S2, the granulated powder is calcined at 1100°C for 6 hours to obtain a specific surface area of ​​3.0 m 2 / g of indium cerium oxide powder;

[0086] In step S5, the sintering temperature is 1400°C.

[0087] It has been detected that the samarium-doped indium cerium oxide target contains In, Ce, and Sm in an atomic ratio of 96.8 / 3 / 0.2, and has a loose porous structure with an average relative density of 62.8%.

[0088] Example 6

[0089] This embodiment provides an ICO target material for reactive plasma deposition coating and a preparation method thereof, which is different from Embodiment 1 in that:

[0090] In step S1, calcination is performed in a muffle furnace at 400°C for 6 hours to obtain a product with a purity of ≥99.99% and a specific surface area of ​​29.8 m 2 / g of samarium-doped indium oxide powder;

[0091] In step S2, the granulated powder is calcined at 1500°C for 10 hours to obtain a specific surface area of ​​0.1 m 2 / g of indium cerium oxide powder;

[0092] In step S5, the sintering temperature is 1250°C.

[0093] It has been detected that the samarium-doped indium cerium oxide target contains In, Ce, and Sm in an atomic ratio of 96.8 / 3 / 0.2, and has a loose porous structure with an average relative density of 64.2%.

[0094] Example 7

[0095] This embodiment provides an ICO target material for reactive plasma deposition coating and a preparation method thereof, which is different from Embodiment 1 in that:

[0096] In step S1, calcination is performed in a muffle furnace at 400°C for 6 hours to obtain a product with a purity of ≥99.99% and a specific surface area of ​​29.8 m 2 / g of samarium-doped indium oxide powder;

[0097] In step S2, the granulated powder is calcined at 1100°C for 6 hours to obtain a specific surface area of ​​3.0 m 2 / g of indium cerium oxide powder;

[0098] In step S5, the sintering temperature is 1300°C.

[0099] It has been detected that the samarium-doped indium cerium oxide target contains In, Ce, and Sm in an atomic ratio of 96.8 / 3 / 0.2, and has a loose porous structure with an average relative density of 63.8%.

[0100] Example 8

[0101] This embodiment provides an ICO target material for reactive plasma deposition coating and a preparation method thereof, which is different from Embodiment 1 in that:

[0102] In step S1, appropriate amounts of indium chloride and samarium nitrate are weighed according to the atomic ratio of In to Sm being 19.36 / 0.2;

[0103] In step S2, appropriate amounts of indium oxide powder and cerium oxide powder with a purity of ≥99.99% are weighed according to an atomic ratio of In to Ce of 77.44 / 3;

[0104] In step S3, appropriate amounts of samarium-doped indium oxide powder and indium-cerium oxide powder are weighed and mixed evenly according to a mass ratio of samarium-doped indium oxide powder to indium-cerium oxide powder of 20 / 80.

[0105] It has been detected that the samarium-doped indium cerium oxide target contains In, Ce, and Sm in an atomic ratio of 96.8 / 3 / 0.2, and has a loose porous structure with an average relative density of 60.1%.

[0106] Example 9

[0107] This embodiment provides an ICO target material for reactive plasma deposition coating and a preparation method thereof, which is different from Embodiment 1 in that:

[0108] In step S1, appropriate amounts of indium chloride and samarium nitrate are weighed according to the atomic ratio of In to Sm being 38.72 / 0.2;

[0109] In step S2, appropriate amounts of indium oxide powder and cerium oxide powder with a purity of ≥99.99% are weighed according to an atomic ratio of In to Ce of 58.08 / 3;

[0110] In step S3, appropriate amounts of samarium-doped indium oxide powder and indium-cerium oxide powder are weighed and uniformly mixed according to a mass ratio of samarium-doped indium oxide powder to indium-cerium oxide powder of 40 / 60.

[0111] It has been detected that the samarium-doped indium cerium oxide target contains In, Ce, and Sm in an atomic ratio of 96.8 / 3 / 0.2, and has a loose porous structure with an average relative density of 61.5%.

[0112] Example 10

[0113] This embodiment provides an ICO target material for reactive plasma deposition coating and a preparation method thereof, which is different from Embodiment 1 in that:

[0114] In step S1, appropriate amounts of indium chloride and samarium nitrate are weighed according to the atomic ratio of In to Sm being 18.9 / 0.5;

[0115] In step S2, appropriate amounts of indium oxide powder and cerium oxide powder with a purity of ≥99.99% are weighed according to an atomic ratio of In to Ce of 75.6 / 5;

[0116] It has been detected that the samarium-doped indium cerium oxide target contains In, Ce, and Sm in an atomic ratio of 94.5 / 5 / 0.5, and has a loose porous structure with an average relative density of 60.7%.

[0117] Embodiment 11

[0118] This embodiment provides an ICO target material for reactive plasma deposition coating and a preparation method thereof, which is different from Embodiment 1 in that:

[0119] In step S1, appropriate amounts of indium chloride and samarium nitrate are weighed according to the atomic ratio of In to Sm being 19.799 / 0.001;

[0120] In step S2, appropriate amounts of indium oxide powder and cerium oxide powder with a purity of ≥99.99% are weighed according to an atomic ratio of In to Ce of 79.20 / 1;

[0121] It has been detected that the samarium-doped indium cerium oxide target contains In, Ce, and Sm in an atomic ratio of 98.999 / 1 / 0.001, and has a loose porous structure with an average relative density of 60.3%.

[0122] Comparative Example 1

[0123] This comparative example provides an ITO (indium tin oxide) target material and a preparation method thereof.

[0124] The preparation method of the ITO target material comprises the following steps:

[0125] S1: According to the atomic ratio of In and Sn being 96.8 / 3.2, appropriate amounts of indium oxide powder and tin oxide powder were weighed and added into a sand mill filled with pure water, and then a mixture of polyethylene glycol and ammonium polyacrylate (dispersant), a mixture of polyvinyl alcohol and polyacrylamide (binder), and polyoxypropylene glycerol ether (defoaming agent) were added. The total solid content was controlled at about 65%, and the mixture was mixed and ball-milled for 10 hours to obtain an indium tin oxide slurry;

[0126] S2: After the indium tin oxide slurry is passed through a 300-mesh sieve, it is introduced into a centrifugal spray granulator with an inlet temperature of 200°C and an outlet temperature of 90°C to obtain indium tin oxide granulated powder; the indium tin oxide granulated powder is calcined at 1350°C for 8 hours to obtain a specific surface area of ​​1.4 m 2 / g of indium tin oxide powder;

[0127] S3: Indium tin oxide powder is loaded into a stainless steel mold, preformed with a hydraulic press, and then cold isostatically pressed at a pressure of 100 MPa to obtain a target blank;

[0128] S4: The target blank is sintered at a high temperature of 1450° C. for 24 hours in an oxygen atmosphere with a pressure of 0.10 MPa, and after machining, an ITO target of standard size is obtained.

[0129] According to the detection, the ITO target material contains In and Sn with an atomic ratio of 96.8 / 3.2 and has a loose porous structure with an average relative density of 62.5%.

[0130] Comparative Example 2

[0131] This embodiment provides an ICO (Indium Cerium Oxide) target material and a preparation method thereof.

[0132] The preparation method of ICO target material comprises the following steps:

[0133] S1: According to the atomic ratio of In and Ce being 96.8 / 3.2, appropriate amounts of indium oxide powder and cerium oxide powder are weighed and added into a sand mill filled with pure water, and then a mixture of polyethylene glycol and ammonium polyacrylate, a mixture of polyvinyl alcohol and polyacrylamide, and polyoxypropylene glycerol ether are added. The total solid content is controlled at about 65%, and the mixture is ball-milled for 10 hours to obtain an indium oxide cerium slurry;

[0134] S2: After the indium cerium oxide slurry is passed through a 300-mesh sieve, it is introduced into a centrifugal spray granulator with an inlet temperature of 200°C and an outlet temperature of 90°C to obtain indium cerium oxide granulated powder; the indium cerium oxide granulated powder is calcined at 1350°C for 8 hours to obtain a specific surface area of ​​1.2 m 2 / g of indium cerium oxide powder;

[0135] S3: The indium cerium oxide powder is loaded into a stainless steel mold, preformed with a hydraulic press, and then cold isostatically pressed at a pressure of 100 MPa to obtain a target blank;

[0136] S4: The target blank is sintered at a high temperature of 1450° C. for 24 hours in an oxygen atmosphere with a pressure of 0.10 MPa, and after machining, an ICO target of standard size is obtained.

[0137] After testing, the ICO target material contains In and Ce with an atomic ratio of 96.8 / 3.2, and has a loose porous structure with an average relative density of 62.9%.

[0138] Comparative Example 3

[0139] This embodiment provides an ICO target material and a preparation method thereof.

[0140] The preparation method of ICO target material comprises the following steps:

[0141] S1: According to the atomic ratio of In and Ni being 29.04 / 0.2, weigh appropriate amounts of indium chloride and nickel chloride; dissolve indium chloride and nickel chloride in water, then add urea and mix evenly, so that the pH of the reaction system is 9 to form a mixed solution; transfer the mixed solution to the inner tank of the reactor, and add appropriate amount of deionized water so that the final volume of the mixed solution is 70% of the volume of the inner tank of the reactor, put the reactor into a drying oven at 200°C for hydrothermal reaction for 12 hours, and then use deionized water and anhydrous ethanol to repeatedly wash the precipitate obtained by centrifugation, and after drying, calcine in a muffle furnace at 600°C for 8 hours to obtain a precipitate with a purity of ≥99.99% and a specific surface area of ​​15.6m 2 / g of nickel-doped indium oxide powder (In 2-x Ni x O3);

[0142] S2: According to the atomic ratio of In and Ce of 67.76 / 3, appropriate amounts of indium oxide powder and cerium oxide powder with a purity of ≥99.99% were weighed and added into pure water, and then hexadecyl sulfonate, gelatin, and polyoxypropylene glycerol ether were added and ball-milled for 10 hours. The total solid content was controlled at about 65%, and the mixed slurry obtained by ball milling was introduced into a centrifugal spray granulator with an inlet temperature of 180°C and an outlet temperature of 80°C to obtain granulated powder; the granulated powder was calcined at 1350°C for 8 hours to obtain a specific surface area of ​​1.2 m 2 / g of indium cerium oxide powder;

[0143] S3: according to the mass ratio of nickel-doped indium oxide powder to indium-cerium oxide powder being 30 / 70, appropriate amounts of nickel-doped indium oxide powder and indium-cerium oxide powder are weighed and mixed evenly, and granulated to obtain a mixed powder;

[0144] S4: The mixed powder is loaded into a stainless steel mold, formed by a hydraulic press, and then cold isostatically pressed at a pressure of 100 MPa to obtain a target blank;

[0145] S5: The target blank is sintered at a high temperature of 1350° C. for 36 hours in an oxygen atmosphere with a pressure of 0.05 MPa, and after machining, a standard-sized nickel-doped indium cerium oxide target is obtained.

[0146] It has been detected that the nickel-doped indium cerium oxide target contains In, Ce, and Ni in an atomic ratio of 96.8 / 3 / 0.2, and has a loose porous structure with an average relative density of 60.1%.

[0147] Comparative Example 4

[0148] This comparative example provides an ICO target material for reactive plasma deposition coating and a preparation method thereof.

[0149] The method for preparing an ICO target material for reactive plasma deposition coating comprises the following steps:

[0150] S1: According to the atomic ratio of In, Ce, Sm of 29.04 / 3 / 0.2, weigh an appropriate amount of specific surface area greater than 30m 2 / g of indium oxide powder, cerium oxide powder and samarium oxide powder are added to a sand mill filled with pure water, and then hexadecyl sulfonate, gelatin and polyoxypropylene glycerol ether are added. The total solid content is controlled at about 65%, and the mixture is ball-milled for 10 hours to obtain a mixed slurry; after drying, it is calcined in a muffle furnace at 600°C for 8 hours to obtain a slurry with a purity of ≥99.99% and a specific surface area of ​​15.3m 2 / g of indium oxide powder doped with samarium cerium (In 2-x-y Ce x Sm y O3);

[0151] S2: Take a specific surface area greater than 30m 2 / g indium oxide powder was calcined at 1350℃ for 8h to obtain a specific surface area of ​​1.3m 2 / g of indium oxide powder;

[0152] S3: taking appropriate amounts of indium oxide powder doped with samarium cerium and indium cerium oxide powder and mixing them evenly to obtain a mixed powder according to a mass ratio of indium oxide powder doped with samarium cerium and indium cerium oxide powder of 30 / 70;

[0153] S4: The mixed powder is loaded into a stainless steel mold, formed by a hydraulic press, and then subjected to cold isostatic pressing at a pressure of 100 MPa to obtain a target blank;

[0154] S5: The target blank is sintered at a high temperature of 1350° C. for 24 hours in an oxygen atmosphere with a pressure of 0.10 MPa, and after machining, a standard-sized samarium-doped indium cerium oxide target is obtained.

[0155] It has been detected that the samarium-doped indium cerium oxide target contains In, Ce, and Sm in an atomic ratio of 96.8 / 3 / 0.2, and has a loose porous structure with an average relative density of 60.7%.

[0156] Related performance test analysis:

[0157] 1. From Figure 1 From the cross-sectional microscopic morphology of the ICO target material of Example 1, it can be seen that Figure 1 It can be seen that the target material has a porous structure, the grains are well fused, and sintering necks are formed to connect them together, indicating that the bonding between the particles is very strong.

[0158] 2. The ICO targets prepared in Examples 1 to 11 and the targets prepared in Comparative Examples 1 to 4 were subjected to reactive plasma deposition (RPD). Specifically, the targets were placed in a water-cooled crucible of the RPD equipment, white glass was used as the sample substrate, and the vacuum pressure was pumped to 0.1×10 -3 Pa, introduce argon and oxygen mixed gas, wherein the oxygen flow rate is 85sccm, the content is 25%, the chamber pressure after filling is 0.4Pa, the DCG current is 145A, adjust the electron gun angle and inclination, focus the plasma beam spot to the target surface for stable ignition, start coating to obtain a transparent conductive oxide film, the film thickness is controlled within the range of 100±10nm, and then anneal in an air atmosphere at 210℃ for 15min; the photoelectric performance of the annealed film is tested; the test results are shown in Table 1 below:

[0159] Table 1

[0160] sample Film thickness(nm) Square resistance (Ω / □) Average transmittance (%) <![CDATA[Mobility (cm 2 / V·s)]]> Example 1 102.15 22.37 87.91 163.68 Example 2 101.91 22.29 88.12 164.05 Example 3 103.12 20.35 88.61 164.91 Example 4 102.39 24.90 87.32 157.10 Example 5 104.08 25.23 86.84 156.31 Example 6 103.60 24.51 86.88 157.12 Example 7 99.81 24.16 87.07 157.89 Example 8 102.51 22.74 87.85 162.42 Example 9 101.69 22.82 87.98 161.89 Example 10 98.98 23.16 87.62 159.13 Embodiment 11 102.13 23.58 86.90 158.24 Comparative Example 1 104.31 48.52 82.50 55.98 Comparative Example 2 98.68 30.49 83.83 139.05 Comparative Example 3 103.72 34.17 84.42 120.12 Comparative Example 4 99.26 27.55 85.41 142.20

[0161] It can be seen from Table 1 that the sheet resistance of the transparent conductive oxide film prepared by the ICO target provided in Examples 1 to 11 is smaller than that of the transparent conductive oxide film prepared by the target provided in Comparative Examples 1 to 4, and the average transmittance and mobility of the transparent conductive oxide film prepared by the ICO target provided in Examples 1 to 11 are higher than that of the transparent conductive oxide film prepared by the target provided in Comparative Examples 1 to 4. It can be seen that the sheet resistance, average transmittance and mobility of the transparent conductive oxide film prepared by the ICO target provided in the embodiment of the present invention are significantly improved compared with the ITO target, ICO target and ICO target doped with Ni (i.e., ICO target doped with non-lanthanide rare earth elements), indicating that the present invention can reduce the sheet resistance of the transparent conductive oxide film by co-doping Ce and other lanthanide rare earth elements, and improve the sheet resistance of the transparent conductive oxide film. The average transmittance and mobility are compared with the transparent conductive oxide film prepared by the ICO target material prepared by mixing the lanthanide rare earth metal oxide, cerium oxide and indium oxide with indium oxide powder prepared by ball milling in Comparative Example 4, the sheet resistance, average transmittance and mobility of the transparent conductive oxide film prepared by the ICO target material provided by the embodiment of the present invention are also significantly improved, indicating that the indium cerium oxide powder doped with X is first prepared as the first component by the hydrothermal method, and then the indium cerium oxide powder is prepared as the second component, and then the two are mixed. By matching the particle sizes of the two components, Ce and X can be uniformly doped in indium oxide to form the ICO target material, which can effectively prevent the formation of multiple intermediate compounds or segregation phases during the sintering process, and greatly improve the uniformity of the ICO target material structure. Therefore, the ICO target material of the present invention can have a higher average transmittance and mobility at the same time, and effectively prevent the ICO target material from having color difference and cracking during coating (such as Figure 2 shown).

[0162] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An ICO target material for reactive plasma deposition coating, characterized in that: An oxide comprising In, Ce and X, wherein the atomic ratio of In, Ce and X is (95-99) / (1-5) / (0.001-0.5); Wherein, the X is selected from at least one of the lanthanide rare earth elements except Ce; The ICO target material has a loose porous structure and a relative density of 55-65%; The ICO target material is sintered by X-doped indium oxide powder and indium cerium oxide powder; The steps of preparing the X-doped indium oxide powder include: Dissolving indium salt, X salt and precipitant in a solvent to form a mixed solution; The mixed solution is transferred to a reaction kettle, subjected to a hydrothermal reaction treatment, and then sequentially subjected to solid-liquid separation, washing, drying and a first calcination treatment to obtain X-doped indium oxide powder.

2. The ICO target material for reactive plasma deposition coating according to claim 1, characterized in that: The X is selected from at least one of La, Sm, Pr, Tb, Gd, and Lu.

3. The ICO target material for reactive plasma deposition coating according to claim 2, characterized in that: The X includes a first lanthanide rare earth element and a second lanthanide rare earth element in an atomic ratio of (0.0005-0.3) / (0.0005-0.2); The first lanthanide rare earth element is selected from at least one of La and Sm, and the second lanthanide rare earth element is selected from at least one of Pr, Tb, Gd and Lu.

4. A method for preparing an ICO target material for reactive plasma deposition coating according to any one of claims 1 to 3, characterized in that: The steps include: preparing X-doped indium oxide powder and indium cerium oxide powder respectively; The cerium indium oxide powder and the X-doped indium oxide powder are uniformly mixed to obtain a mixed powder; Molding the mixed powder to obtain a target blank; The target material is sintered at high temperature to obtain an ICO target material.

5. The preparation method according to claim 4, characterized in that: The specific surface area of ​​the X-doped indium oxide powder is 10-30 m 2 / g, the specific surface area of ​​the indium cerium oxide powder is 0.1~3.0m 2 / g; And / or, the mass ratio of the X-doped indium oxide powder to the indium cerium oxide powder is (20-40) / (60-80).

6. The preparation method according to claim 4, characterized in that: The hydrothermal reaction treatment is performed at a temperature of 150-250°C and a time of 12-24 hours; And / or, the temperature of the first calcination treatment is 400-800° C. and the time is 6-10 hours.

7. The preparation method according to claim 4, characterized in that: The indium salt is selected from indium chloride or indium nitrate; The X salt is selected from a chloride of X or a nitrate of X.

8. The preparation method according to any one of claims 5 to 7, characterized in that The steps of preparing indium cerium oxide powder include: Indium oxide powder and cerium oxide powder are added into pure water, and then a dispersant, a binder and a defoamer are added to perform ball milling and mixing, and then spray granulation is performed to obtain granulated powder; The granulated powder is subjected to a second calcination treatment to obtain indium cerium oxide powder.

9. The preparation method according to claim 8, characterized in that: At least one of the following conditions is met: The inlet temperature of the spray granulation is 180-220°C, and the outlet temperature is 80-100°C; The temperature of the second calcination treatment is 1000-1500°C and the time is 6-10h; The molding comprises: performing cold isostatic pressing at a pressure of 50-200 MPa.

10. The preparation method according to claim 8, characterized in that: The high-temperature sintering atmosphere is oxygen, the pressure is 0.05-0.10 MPa, the temperature is 1000-1550° C., and the time is 8-36 hours.

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