High mobility ceramic target material, method of making and use thereof

Abstract

The application provides a high-mobility ceramic target material and a preparation method and application thereof, and belongs to the technical field of ceramic materials. In the application, indium oxide is used as a main body, and two or more of titanium oxide, zirconium oxide, gallium oxide, tantalum oxide, tungsten oxide, molybdenum oxide and rare earth oxides are introduced as doped oxides to construct a doped system covering "double-element co-doping-multiple-doping". The core of the doped system is to realize comprehensive regulation of carrier concentration, lattice distortion and defect type in the indium oxide lattice through the functional complementation and synergistic effect of different elements, so as to optimize the carrier transport path and inhibit the scattering mechanism. The ceramic target material prepared based on the doped system has high density, low resistivity and excellent component uniformity. The transparent conductive thin film deposited by the ceramic target material through a magnetron sputtering process and the like exhibits excellent photoelectric performance.

Description

Technical Field

[0001] This invention relates to the field of ceramic target technology, and in particular to a high-mobility ceramic target, its preparation method, and its application. Background Technology

[0002] Indium tin oxide (ITO) thin films, as a typical representative of transparent conductive oxide thin films, not only possess excellent conductivity and high transmittance in the visible light region, but also exhibit good corrosion resistance, environmental stability, mature large-area film deposition technology, and relatively low cost. Therefore, they are widely used as key basic materials for flat panel displays and solar cells. Traditional ITO materials are limited by single-element (Sn)... 4+ The doping strategy inherently presents a trade-off between carrier concentration and mobility: while increasing the Sn doping amount can increase carrier concentration, excessive Sn... 4+ These particles act as scattering centers for ionized impurities, severely degrading mobility and leading to decreased electrical stability of the film in subsequent processes or during use. Furthermore, single-doped systems are extremely sensitive to fabrication processes (such as sputtering oxygen partial pressure), have narrow process windows, and are difficult to control in terms of repeatability. Therefore, the low carrier mobility and insufficient infrared transmittance of traditional ITO materials limit further improvements in device performance.

[0003] Therefore, developing a novel ceramic target material, aiming to break the traditional trade-off between carrier concentration and mobility, and to simultaneously improve the comprehensive optoelectronic performance (high mobility, low resistivity, high transmittance, and high stability) of conductive oxide thin films, has become a technical bottleneck that urgently needs to be overcome in this field. Summary of the Invention

[0004] The purpose of this invention is to provide a high-mobility ceramic target, its preparation method, and its application. The high-mobility ceramic target provided by this invention has low resistivity and high density, which enables the prepared conductive oxide thin film to have low resistivity, high mobility, and high light transmittance.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a high-mobility ceramic target material, comprising the following raw materials by mass percentage: 98-99.5% indium oxide and 0.5-2% doped oxide; wherein the doped oxide includes two or more of titanium oxide, zirconium oxide, gallium oxide, tantalum oxide, tungsten oxide, molybdenum oxide, and rare earth oxides.

[0006] Preferably, the doped oxide includes two of titanium oxide, gallium oxide, zirconium oxide, tantalum oxide, and rare earth oxides.

[0007] Preferably, by mass percentage, it comprises: 0-0.5% titanium oxide, 0-1.0% gallium oxide, and 0-1.0% zirconium oxide; wherein one of the titanium oxide, gallium oxide, and zirconium oxide is 0%.

[0008] Preferably, the doped oxide includes two or more of titanium oxide, gallium oxide, zirconium oxide and tantalum oxide, and the doped metal oxide includes one or more of tungsten oxide, molybdenum oxide and rare earth oxide.

[0009] Preferably, by mass percentage, it comprises: 0-0.5% titanium oxide, 0-0.1% gallium oxide, 0-0.1% zirconium oxide, and 0.1-0.3% doped metal oxide.

[0010] Preferably, the doped oxide includes titanium oxide, gallium oxide, and tungsten oxide; This may include titanium oxide, gallium oxide, and molybdenum oxide; This may include titanium oxide, gallium oxide, and rare earth oxides; This may include titanium oxide, zirconium oxide, and tungsten oxide; This may include titanium oxide, zirconium oxide, and molybdenum oxide; This may include titanium oxide, zirconium oxide, and rare earth oxides; This may include gallium oxide, zirconium oxide, and tungsten oxide; This may include gallium oxide, zirconium oxide, and molybdenum oxide; This may include gallium oxide, zirconium oxide, and rare earth oxides; This may include titanium oxide, gallium oxide, zirconium oxide, and tungsten oxide; This may include titanium oxide, gallium oxide, zirconium oxide, and molybdenum oxide; This may include titanium oxide, gallium oxide, zirconium oxide, and rare earth oxides; It may include titanium oxide, gallium oxide, zirconium oxide, tungsten oxide, and rare earth oxides.

[0011] The present invention also provides a method for preparing the high-mobility ceramic target described in the above technical solution, comprising: Indium oxide, doped oxide, dispersant, binder, defoamer, and deionized water are mixed to obtain a mixed slurry; the doped oxide includes two or more of titanium oxide, zirconium oxide, gallium oxide, tantalum oxide, tungsten oxide, molybdenum oxide, and rare earth oxides. The mixed slurry is spray-granulated to obtain granulated powder; The granulated powder is subjected to cold pressing and cold isostatic pressing in sequence to obtain a ceramic body. The ceramic preform is sintered to obtain a multi-element doped high-mobility ceramic target. Preferably, the pressure of the cold pressing treatment is 20~40MPa; the holding time of the cold pressing treatment is 1~3min; the pressure of the cold isostatic pressing treatment is 200~300MPa; and the holding time of the cold isostatic pressing treatment is 1~60min.

[0012] Preferably, the sintering process includes sequential degreasing sintering, low-temperature sintering, and high-temperature sintering; The heating rate for the degreasing sintering is 0.1~5℃ / min; the degreasing sintering temperature is 600~750℃; and the holding time for the degreasing sintering is 5~10h. The heating rate from degreasing sintering to low-temperature sintering is 0.1~5℃ / min; the temperature of low-temperature sintering is 1200~1300℃; and the holding time of low-temperature sintering is 5~10h. The heating rate from low-temperature sintering to high-temperature sintering is 0.1~5℃ / min; the high-temperature sintering temperature is 1300~1500℃, and the holding time for high-temperature sintering is 12~36h.

[0013] The present invention also provides the application of the high mobility ceramic target described in the above technical solution or the high mobility ceramic target prepared by the preparation method described in the above technical solution in solar cells, thin film transistors or display devices.

[0014] This invention provides a high-mobility ceramic target material, comprising, by mass percentage, the following raw materials: 98-99.5% indium oxide and 0.5-2% doped oxides; the doped oxides include two or more selected from titanium oxide, zirconium oxide, gallium oxide, tantalum oxide, tungsten oxide, molybdenum oxide, and rare earth oxides. This invention uses indium oxide as the main component and introduces two or more selected from titanium oxide, zirconium oxide, gallium oxide, tantalum oxide, tungsten oxide, molybdenum oxide, and rare earth oxides as doped oxides, constructing a doping system encompassing "dual-element co-doping - multi-element doping". The core of this doping system lies in achieving comprehensive control of carrier concentration, lattice distortion, and defect type within the indium oxide lattice through the complementary and synergistic effects of different elements, thereby optimizing carrier transport paths and suppressing scattering mechanisms. The ceramic target material prepared based on this doping system exhibits high density, low resistivity, and excellent compositional uniformity. The transparent conductive thin film deposited using the ceramic target material through processes such as magnetron sputtering exhibits excellent photoelectric properties. The results of the embodiments show that the high-mobility ceramic target provided by the present invention has a significantly better mobility than traditional ITO thin films, while maintaining an average visible light transmittance of over 85% and a low resistivity. This results in a high-quality ceramic target with a relative density of ≥99%, resistivity uniformity of ≤5%, and a uniform microstructure without abnormally large grains, ensuring the stability of the sputtering process and the consistency of the thin film. Detailed Implementation

[0015] This invention provides a high-mobility ceramic target material, comprising the following raw materials by mass percentage: 98-99.5% indium oxide and 0.5-2% doped oxide; wherein the doped oxide includes two or more of titanium oxide, zirconium oxide, gallium oxide, tantalum oxide, tungsten oxide, molybdenum oxide, and rare earth oxides.

[0016] The raw materials for preparing the high-mobility ceramic target of the present invention comprise 98-99.5% indium oxide by mass percentage. As one embodiment of the present invention, the mass percentage of indium oxide can be 98%, 98.5%, 99.0%, 99.1%, 99.2%, 99.3%, 99.4%, or 99.5%. The present invention uses indium oxide as the main oxide.

[0017] The raw materials for preparing the high-mobility ceramic target of the present invention, by mass percentage, include 0.5-2% doped oxide. As one embodiment of the present invention, the mass percentage of the doped oxide can be 0.5%, 0.7%, 0.8%, 1.0%, 1.2%, 1.5%, 1.6%, 1.8%, or 2%.

[0018] In this invention, the doped oxide includes two or more of titanium oxide, zirconium oxide, gallium oxide, tantalum oxide, tungsten oxide, molybdenum oxide, and rare earth oxides. Preferably, the rare earth oxide includes cerium oxide or holmium oxide. This invention introduces two or more of titanium oxide, zirconium oxide, gallium oxide, tantalum oxide, tungsten oxide, molybdenum oxide, and rare earth oxides as doped oxides, constructing a doping system encompassing "dual-element co-doping - multi-element doping". The core of this doping system lies in achieving comprehensive control over carrier concentration, lattice distortion, and defect types in the indium oxide lattice through the complementary and synergistic effects of different elements, thereby optimizing carrier transport paths and suppressing scattering mechanisms.

[0019] In one embodiment of the present invention, the doped oxide preferably includes two of titanium oxide, gallium oxide, zirconium oxide, tantalum oxide, and rare earth oxides. The present invention utilizes two of titanium oxide, gallium oxide, zirconium oxide, tantalum oxide, and rare earth oxides as doped oxides to construct a "carrier donor-lattice stabilizer" type: such as Ti. 4+ and Ga 3+ Zr 4+ and Ga 3+ Ti 4+ and Zr 4+ Combinations such as Zr 4+ Ti 4+ Ga efficiently provides free electrons, while 3+ It can alleviate lattice distortion caused by ion radius mismatch and reduce scattering of ionized impurities, thereby maintaining extremely high mobility at high carrier concentrations. "Band / defect engineering" type: such as introducing (Ce)4+ / 3+ Ta 5+ Combinations of elements with variable valence properties or deep-level modulation capabilities are used to modify the bottom electronic states of the conduction band, passivate deep-level trap centers, reduce electron capture, and improve mobility and stability.

[0020] The doped oxide preferably comprises 0-0.5% titanium oxide by mass percentage. As an embodiment of the present invention, the mass percentage of titanium oxide may be 0.1%, 0.2%, 0.3%, 0.4%, or 0.5%.

[0021] The doped oxide preferably comprises 0 to 1.0% gallium oxide by mass percentage. As an embodiment of the invention, the mass percentage of gallium oxide can be 0.1%, 0.5%, 0.6%, 0.8%, or 1.0%.

[0022] The doped oxide preferably comprises 0 to 1.0% zirconium oxide by mass percentage. As an embodiment of the present invention, the mass percentage of zirconium oxide may be 0.1%, 0.5%, 0.6%, 0.8%, or 1.0%.

[0023] The doped oxide preferably comprises 0-0.5% tantalum oxide by mass percentage. As an embodiment of the present invention, the mass percentage of tantalum oxide can be 0.1%, 0.2%, 0.3%, 0.4%, or 0.5%.

[0024] The doped oxide preferably comprises 0-0.3% rare earth oxide by mass percentage. As an embodiment of the present invention, the mass percentage of the rare earth oxide can be 0.1%, 0.2%, or 0.3%.

[0025] In embodiments of the present invention, the doped oxide may be titanium oxide and gallium oxide, titanium oxide and zirconium oxide, or zirconium oxide and gallium oxide. The mass ratio of titanium oxide to gallium oxide is preferably (1~2):(1~4), more preferably 1:2; the mass ratio of titanium oxide to zirconium oxide is preferably (1~2):(1~4), more preferably 1:2; the mass ratio of zirconium oxide to gallium oxide is preferably (1~2):(1~4), more preferably 1:2.

[0026] In one embodiment of the present invention, the doped oxide preferably includes two or more of titanium oxide, gallium oxide, zirconium oxide, and tantalum oxide, and a doped metal oxide, wherein the doped metal oxide includes one or more of tungsten oxide, molybdenum oxide, and rare earth oxides. Based on dual-element co-doping, the present invention introduces a third or more trace elements to finely control the microstructure, grain boundary characteristics, and defect chemistry of the material. The introduction of tungsten oxide can further broaden the process oxygen partial pressure window corresponding to optimal photoelectric performance; the addition of rare earth oxides can suppress abnormal grain growth during sintering, improving the microstructure uniformity and density of the ceramic target material.

[0027] The doped oxide preferably comprises 0-0.5% titanium oxide by mass percentage. As an embodiment of the present invention, the mass percentage of titanium oxide may be 0.1%, 0.2%, 0.3%, 0.4%, or 0.5%.

[0028] The doped oxide preferably comprises 0 to 0.6% gallium oxide by mass percentage. As an embodiment of the present invention, the mass percentage of gallium oxide may be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, or 0.6%.

[0029] The doped oxide preferably comprises 0 to 0.5% zirconium oxide by mass percentage. As an embodiment of the present invention, the mass percentage of zirconium oxide may be 0.1%, 0.2%, 0.3%, 0.4%, or 0.5%.

[0030] The doped oxide preferably comprises 0-0.3% tantalum oxide by mass percentage. As an embodiment of the present invention, the mass percentage of tantalum oxide may be 0.05%, 0.1%, 0.15%, 0.2%, or 0.3%.

[0031] The doped oxide preferably comprises 0.1 to 0.3% doped metal oxide by mass percentage. As an embodiment of the present invention, the mass percentage of the doped metal oxide may be 0.1%, 0.15%, 0.2%, 0.25%, or 0.3%.

[0032] In this invention, the doped oxide preferably includes titanium oxide, gallium oxide and tungsten oxide, and the mass ratio of titanium oxide, gallium oxide and tungsten oxide is preferably (0.3~5):(0.5~5):(0.1~2), more preferably 0.3:0.6:0.1.

[0033] Alternatively, the doped oxide preferably includes titanium oxide, gallium oxide and molybdenum oxide, and the mass ratio of the doped oxide to titanium oxide, gallium oxide and molybdenum oxide is preferably (0.3~5):(0.5~5):(0.1~2), more preferably 0.3:0.6:0.1.

[0034] Alternatively, the doped oxide preferably includes titanium oxide, gallium oxide and rare earth oxide, and the mass ratio of the titanium oxide, gallium oxide and rare earth oxide is preferably (0.3~5):(0.5~5):(0.1~2), more preferably 0.3:0.6:0.1.

[0035] Alternatively, the doped oxide preferably includes titanium oxide, zirconium oxide and tungsten oxide, and the mass ratio of titanium oxide, zirconium oxide and tungsten oxide is preferably (0.3~5):(0.5~5):(0.1~2), more preferably 0.3:0.6:0.1.

[0036] Alternatively, the doped oxide preferably includes titanium oxide, zirconium oxide and molybdenum oxide, and the mass ratio of titanium oxide, zirconium oxide and molybdenum oxide is preferably (0.3~5):(0.5~5):(0.1~2), more preferably 0.3:0.6:0.1.

[0037] Alternatively, the doped oxide preferably includes titanium oxide, zirconium oxide and rare earth oxide, and the mass ratio of the titanium oxide, zirconium oxide and rare earth oxide is preferably (0.3~5):(0.5~5):(0.1~2), more preferably 0.3:0.6:0.1.

[0038] Alternatively, the doped oxide preferably includes gallium oxide, zirconium oxide and tungsten oxide, and the mass ratio of gallium oxide, zirconium oxide and tungsten oxide is preferably (0.3~5):(0.5~5):(0.1~2), more preferably 0.3:0.6:0.1.

[0039] Alternatively, the doped oxide preferably includes gallium oxide, zirconium oxide and molybdenum oxide, and the mass ratio of gallium oxide, zirconium oxide and molybdenum oxide is preferably (0.3~5):(0.5~5):(0.1~2), more preferably 0.3:0.6:0.1.

[0040] Alternatively, the doped oxide preferably includes gallium oxide, zirconium oxide and rare earth oxide, and the mass ratio of gallium oxide, zirconium oxide and rare earth oxide is preferably (0.3~5):(0.5~5):(0.1~2), more preferably 0.3:0.6:0.1.

[0041] Alternatively, the doped oxide preferably includes titanium oxide, gallium oxide, zirconium oxide and tungsten oxide, and the mass ratio of titanium oxide, gallium oxide, zirconium oxide and tungsten oxide is preferably (0.3~5):(0.5~5):(0.1~5):(0.5~2), more preferably 0.3:0.6:0.1:.

[0042] Alternatively, the doped oxide preferably includes titanium oxide, gallium oxide, zirconium oxide and molybdenum oxide, and the mass ratio of titanium oxide, gallium oxide, zirconium oxide and molybdenum oxide is preferably (0.2~5):(0.3~5):(0.3~5):(0.1~2), more preferably 0.2:0.3:0.3:0.1.

[0043] Alternatively, the doped oxide preferably includes titanium oxide, gallium oxide, zirconium oxide and rare earth oxide, and the mass ratio of the titanium oxide, gallium oxide, zirconium oxide and rare earth oxide is preferably (0.2~5):(0.3~5):(0.3~5):(0.1~2), more preferably 0.2:0.3:0.3:0.1 or 0.2:0.3:0.3:0.2.

[0044] Alternatively, the doped oxide preferably includes titanium oxide, gallium oxide, zirconium oxide, tungsten oxide and rare earth oxide, and the mass ratio of the titanium oxide, gallium oxide, zirconium oxide, tungsten oxide and rare earth oxide is preferably (0.2~5):(0.3~5):(0.3~5):(0.1~2):(0.1~2), more preferably 0.2:0.3:0.3:0.1:0.1.

[0045] The present invention also provides a method for preparing the high-mobility ceramic target described in the above technical solution, comprising: Indium oxide, doped oxide, dispersant, binder, defoamer, and deionized water are mixed to obtain a mixed slurry; the doped oxide includes two or more of titanium oxide, zirconium oxide, gallium oxide, tantalum oxide, tungsten oxide, molybdenum oxide, and rare earth oxides. The mixed slurry is spray-granulated to obtain granulated powder; The granulated powder is subjected to cold pressing and cold isostatic pressing in sequence to obtain a ceramic body. The ceramic blank is sintered to obtain a multi-element doped high-mobility ceramic target.

[0046] Unless otherwise specified, all raw materials used in this invention are commercially available products well known to those skilled in the art.

[0047] This invention involves mixing indium oxide, doped oxide, dispersant, binder, defoamer, and deionized water to obtain a mixed slurry.

[0048] In this invention, the doped oxide includes two or more of titanium oxide, zirconium oxide, gallium oxide, tantalum oxide, tungsten oxide, molybdenum oxide, and rare earth oxides. In this invention, the amounts of indium oxide and the doped oxide are the same as those in the above-described technical solutions, and will not be repeated here.

[0049] In embodiments of the present invention, the purity of the indium oxide and the doped oxide is preferably 4N.

[0050] In embodiments of the present invention, the particle size D50 of the indium oxide and the doped oxide is preferably less than or equal to 0.5 μm.

[0051] In this invention, the dispersant preferably comprises one or more of ammonium polyacrylate, ammonium citrate, polyethyleneimine, and polyvinylpyrrolidone. By adding a dispersant, this invention promotes uniform dispersion of indium oxide and doped oxides in the mixed slurry.

[0052] In this invention, the mass percentage of the dispersant relative to the total mass of indium oxide and doped oxide is preferably 0.1 to 1.0%; as an embodiment of this invention, the mass content of the dispersant relative to the metal oxide powder can be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, or 1.0%.

[0053] In this invention, the binder preferably includes one or more of polyvinyl alcohol, polymethyl methacrylate, polyethylene glycol, and methylcellulose, more preferably polyvinyl alcohol. This invention, by adding a binder, can bond various indium oxides and doped oxides, which is more beneficial for granulation.

[0054] In this invention, the mass percentage of the binder relative to the total mass of indium oxide and doped oxide is preferably 0.1 to 10%; as an embodiment of this invention, the mass content of the binder relative to the metal oxide powder can be 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, or 10%.

[0055] In this invention, the defoamer is preferably polydimethylsiloxane. This invention eliminates bubbles generated during mixing by adding a defoamer.

[0056] In this invention, the mass percentage of the defoamer relative to the total mass of indium oxide and doped oxide is preferably 0.1-0.5%; as an embodiment of this invention, the mass content of the defoamer relative to the metal oxide powder can be 0.1%, 0.2%, 0.3%, 0.4% or 0.5%.

[0057] In this invention, the mass percentage of deionized water to the total mass of indium oxide and doped oxide is preferably 40-70%; as an embodiment of this invention, the mass content of deionized water to the metal oxide powder can be 40%, 45%, 50%, 55%, 60%, 65% or 70%.

[0058] In this invention, the mixing process preferably includes: mixing indium oxide, doped oxide, dispersant, binder, defoamer and deionized water, and then ball milling to obtain a mixed slurry.

[0059] In this invention, the ball milling speed is preferably 2000-3000 rpm, more preferably 2500-3000 rpm; the ball milling time is preferably 1-10 h, more preferably 2-5 h; the ball-to-material ratio is preferably 1:1-2, more preferably 1:1-1.5; the grinding balls used in the ball milling preferably include small balls, medium balls, and large balls, and the mass ratio of the small balls, medium balls, and large balls is preferably (1-5):(1-5):(1-5), more preferably (2-4):(2-4):(2-4). In an embodiment of this invention, the diameter of the small balls can be 0.1 mm, the diameter of the medium balls can be 0.3 mm, and the diameter of the large balls can be 0.6 mm. In an embodiment of this invention, the ball milling can be carried out in a sand mill. This invention, through ball milling, enables the solid particles in the mixed slurry to have a small particle size and narrow distribution, thereby giving the ceramic green body a more uniform microstructure and higher sintering density. In this invention, the solids in the mixed slurry preferably have a D50 of less than or equal to 0.2 μm and a D90 of less than or equal to 0.6 μm.

[0060] After obtaining the mixed slurry, the present invention performs spray granulation on the mixed slurry to obtain granulated powder.

[0061] This invention does not impose any particular limitation on the specific operation method of spray granulation; conventional spray granulation methods can be used. In this invention, the spray granulation temperature is preferably 100~200℃, more preferably 150~200℃.

[0062] After obtaining the granulated powder, the present invention performs cold pressing and cold isostatic pressing on the granulated powder in sequence to obtain a ceramic body.

[0063] In this invention, the pressure of the cold pressing process is preferably 20-40 MPa; the holding time of the cold pressing process is preferably 1-3 min. As an embodiment of this invention, the pressure of the cold pressing process can be 20 MPa, 22 MPa, 24 MPa, 26 MPa, 27.3 MPa, 28 MPa, 30 MPa, 32 MPa, 34 MPa, 36 MPa, 38 MPa, or 40 MPa; the holding time of the cold pressing process can be 1 min, 1.5 min, 2 min, 2.5 min, or 3 min. This invention enables rapid shaping of granulated powder through cold pressing.

[0064] In this invention, the pressure of the cold isostatic pressing treatment is preferably 200-300 MPa; the holding time of the cold isostatic pressing treatment is preferably 1-60 min. As an embodiment of this invention, the pressure of the cold isostatic pressing can be 200 MPa, 210 MPa, 220 MPa, 230 MPa, 240 MPa, 250 MPa, 260 MPa, 270 MPa, 280 MPa, 290 MPa, or 300 MPa; the holding time of the cold isostatic pressing can be 1 min, 10 min, 20 min, 30 min, 40 min, 50 min, or 60 min. This invention enables the ceramic green body to be uniformly densified through cold isostatic pressing.

[0065] After obtaining the ceramic blank, the present invention performs sintering treatment on the ceramic blank to obtain a multi-element doped high-mobility ceramic target.

[0066] In this invention, the sintering process preferably includes degreasing sintering, low-temperature sintering and high-temperature sintering performed sequentially.

[0067] In this invention, the heating rate to the debinding sintering stage is preferably 0.1~5℃ / min; the debinding sintering temperature is preferably 600~750℃; and the holding time for debinding sintering is preferably 5~10h. As an embodiment of this invention, the heating rate to the debinding sintering stage can be 0.1℃ / min, 1℃ / min, 2℃ / min, 3℃ / min, 4℃ / min, or 5℃ / min; the debinding sintering temperature can be 600℃, 650℃, 700℃, or 750℃; and the holding time for debinding sintering can be 5h, 6h, 7h, 8h, 9h, or 10h. This invention can remove organic additives such as binders from the ceramic body through debinding sintering.

[0068] In this invention, the heating rate from degreasing sintering to low-temperature sintering is preferably 0.1~5℃ / min; the low-temperature sintering temperature is preferably 1200~1300℃, and the holding time for low-temperature sintering is preferably 5~10h. As an embodiment of this invention, the heating rate to the low-temperature sintering can be 0.1℃ / min, 1℃ / min, 2℃ / min, 3℃ / min, 4℃ / min, or 5℃ / min; the low-temperature sintering temperature can be 1200℃, 1250℃, 1260℃, or 1300℃; and the holding time for low-temperature sintering can be 5h, 6h, 7h, 8h, 9h, or 10h. This invention enables preliminary sintering, strengthens the green body, and facilitates the transition before sealing pores through low-temperature sintering.

[0069] In this invention, the heating rate from low-temperature sintering to high-temperature sintering is preferably 0.1~5℃ / min; the high-temperature sintering temperature is preferably 1300~1500℃; and the holding time for high-temperature sintering is preferably 12~36h. As an embodiment of this invention, the heating rate to the high-temperature sintering can be 0.1℃ / min, 1℃ / min, 2℃ / min, 3℃ / min, 4℃ / min, or 5℃ / min; the high-temperature sintering temperature can be 1300℃, 1350℃, 1400℃, 1450℃, or 1500℃; and the holding time for high-temperature sintering can be 12h, 15h, 18h, 20h, 24h, 30h, or 36h. This invention enables the green body to shrink rapidly, become dense, and gradually spheroidize its pores through high-temperature sintering. It also allows for the extensive diffusion and fusion of particles within the green body, resulting in moderate grain growth and the formation of a stable microstructure.

[0070] In this invention, the temperature is preferably reduced to 1000°C at a rate of 1°C / min after high-temperature sintering, and then allowed to cool naturally to room temperature.

[0071] In this invention, when the sintering temperature is below 650°C, the sintering atmosphere is preferably air; when the sintering temperature is above 650°C, the sintering atmosphere is preferably oxygen. In this invention, when the sintering atmosphere is oxygen, the oxygen flow rate is preferably 2~20 L / min, more preferably 6~15 L / min. This invention improves sintering efficiency by controlling the sintering atmosphere.

[0072] The present invention preferably involves mechanically grinding, inspecting, and bonding the target material obtained from the sintering process to obtain a high-mobility ceramic target material. The present invention does not impose any particular limitation on the operation method for the mechanical grinding, inspection, and bonding; conventional methods can be used.

[0073] This invention also provides the application of the high-mobility ceramic target described in the above-described technical solutions, or the high-mobility ceramic target prepared by the preparation method described in the above-described technical solutions, in solar cells, thin-film transistors, or display devices. This invention does not impose any special limitations on the methods for these applications; any process well-known to those skilled in the art can be used.

[0074] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0075] Example 1 A method for preparing a high-mobility ceramic target: Weigh out 99.1% indium oxide, 0.3% titanium oxide, and 0.6% gallium oxide by mass percentage and place them in a sand mill jar. Add 50% deionized water (by mass of indium oxide, titanium oxide, and gallium oxide), 0.5% dispersant (ammonium polyacrylate), 5.5% binder (polyvinyl alcohol), and 0.1% defoamer (polydimethylsiloxane). The mixture was then ball-milled in a sand mill at a speed of 2250 rpm. The ball-to-material ratio was 1:1, and the milling media consisted of zirconia balls, including small, medium, and large balls. The diameter of the small balls was 0.1 mm, the diameter of the medium balls was 0.3 mm, and the diameter of the large balls was 0.6 mm. The mass ratio of the small, medium, and large balls was 1:1:1. The milling time was 5 hours, resulting in a mixed slurry. The solids in the mixed slurry had a D50 of 0.15 μm and a D90 of 0.55 μm. After obtaining the mixed slurry, the mixed slurry is spray-granulated at a temperature of 230°C to obtain powder, and the particle size D50 of the granulated powder is 30~50μm; The granulated powder after passing through a 120-mesh sieve is subjected to cold pressing at 27.3 MPa for 3 minutes, and then further subjected to cold isostatic pressing at 270 MPa for 25 minutes to obtain a ceramic green body. The ceramic blank was placed in a sintering furnace and sintered at 650°C with a heating rate of 1°C / min for debinding and holding for 10 hours; then sintered at 1200°C with a heating rate of 1°C for 6 hours; then sintered at 1380°C with a heating rate of 0.5°C / min for 24 hours; and finally cooled to 1000°C with a heating rate of 1°C / min, followed by natural cooling to room temperature to obtain a multi-element doped high-mobility ceramic target. During the sintering process, air was introduced below 650°C and oxygen was introduced above 650°C at a flow rate of 6 L / min. The target obtained after the sintering process was then mechanically polished, inspected, and bonded to obtain a high-mobility ceramic target.

[0076] Example 2 A method for preparing a high-mobility ceramic target: The difference from Example 1 is that the indium oxide is weighed as 99.1%, titanium oxide as 0.3%, and zirconium oxide as 0.6%, while the remaining steps and parameters are the same as in Example 1.

[0077] Example 3 A method for preparing a high-mobility ceramic target: The difference from Example 1 is that the indium oxide is weighed as 99.1%, zirconium oxide as 0.3%, and gallium oxide as 0.6%, while the remaining steps and parameters are the same as in Example 1.

[0078] Example 4 A method for preparing a high-mobility ceramic target: The difference from Example 1 is that the following ingredients were weighed: 99.0% indium oxide, 0.3% titanium oxide, 0.6% gallium oxide, and 0.1% holmium oxide. The remaining steps and parameters are the same as in Example 1.

[0079] Example 5 A method for preparing a high-mobility ceramic target: The difference from Example 1 is that the following ingredients were weighed: 99.0% indium oxide, 0.2% titanium oxide, 0.3% zirconium oxide, 0.3% gallium oxide, and 0.2% holmium oxide. The remaining steps and parameters are the same as in Example 1.

[0080] Example 6 A method for preparing a high-mobility ceramic target: The difference from Example 1 is that the following ingredients were weighed: 99.0% indium oxide, 0.2% titanium oxide, 0.3% zirconium oxide, 0.3% gallium oxide, 0.1% tungsten oxide, and 0.1% holmium oxide. The remaining steps and parameters are the same as in Example 1.

[0081] Comparative Example 1 A method for preparing a ceramic target: The difference from Example 1 is that 90% indium oxide and 10% tin oxide are weighed, while the remaining steps and parameters are the same as in Example 1.

[0082] Comparative Example 2 A method for preparing a ceramic target: The difference from Example 1 is that the indium oxide is weighed at 99.0% and the tin oxide at 1.0%, while the remaining steps and parameters are the same as in Example 1.

[0083] Comparative Example 3 A method for preparing a ceramic target: The difference from Example 1 is that indium oxide 99.5% and gallium oxide 0.5% were weighed, while the remaining steps and parameters were the same as in Example 1.

[0084] Comparative Example 4 A method for preparing a ceramic target: The difference from Example 1 is that 99.5% indium oxide and 0.5% titanium oxide were weighed, while the remaining steps and parameters were the same as in Example 1.

[0085] Comparative Example 5 A method for preparing a ceramic target: The difference from Example 1 is that 99.5% indium oxide and 0.5% zirconium oxide were weighed, while the remaining steps and parameters were the same as in Example 1.

[0086] Test case Performance testing experiments: 1. Processing binding: After the ceramic targets prepared in the examples and comparative examples were processed according to the drawing dimensions, the ceramic targets were bonded to the copper back target with indium and subjected to ultrasonic testing. No dark cracks were found. Then, subsequent coating tests were carried out.

[0087] 2. Coating test: Resistivity: The resistivity of the prepared target material was measured using a four-probe resistivity meter.

[0088] Bending strength: The prepared target material was measured using a universal testing machine.

[0089] After being ultrasonically cleaned with acetone, ethanol, and deionized water for 10-20 minutes and dried with nitrogen, the target materials prepared in the above embodiments and comparative examples were used to deposit the required thin film by magnetron sputtering. The deposition power was 180W, the sputtering pressure was 0.5Pa, the sputtering atmosphere was a mixed gas of H2 / O2, and the film thickness was 100nm.

[0090] Thin film mobility: The prepared thin film was tested using a Hall effect meter.

[0091] Thin film transmittance: The prepared thin film was tested using a UV spectrophotometer at wavelengths of 400~1400nm.

[0092] The performance test results of the ceramic targets prepared in each embodiment and comparative example, and the thin films prepared therefrom, are shown in Table 1.

[0093] Table 1. Performance test results of the thin films prepared in the examples and comparative examples.

[0094] Based on the above performance test results, it can be seen that the ceramic target material prepared by this invention possesses excellent target material performance and can meet the basic application requirements of magnetron sputtering processes. The resistivity of the target materials prepared in the embodiments of this invention is generally lower than that of the comparative examples. Lower target material resistivity is beneficial for the magnetron sputtering process to adopt a more stable DC mode or higher power, improving the deposition rate and process stability. Among them, Example 6 has the lowest resistivity, indicating that the complex doping system, after optimization, can form a superior conductive network. The bending strength of all embodiments is higher than that of Comparative Examples 1-3. This indicates that the doping strategy of this invention not only does not damage the mechanical integrity of the target material, but some combinations also improve the mechanical properties of the ceramic target material due to grain refinement and grain boundary strengthening, which is beneficial for coping with the stress during the bonding and transportation of large-size ceramic targets. Comparative Examples 3-5, through single doping with titanium oxide, gallium oxide, and zirconium oxide, although showing improved film mobility compared to ITO, are all lower than the films prepared with the ceramic target material of the embodiments of this invention. This shows that using the doping method provided by this invention, compared to Ti… 4+ Ga 3+ Zr 4 + Single-element doping allows for more effective control of carrier concentration and helps reduce lattice scattering. Examples 1-3, through bi-element co-doping, demonstrate advantages over single-element doping in carrier control and lattice stability, resulting in better thin film mobility. Examples 4-6 achieve high-mobility thin film fabrication through multi-element doping, strongly proving that multi-element refined doping strategies, through micro-control and defect engineering, can maximize the optimization of carrier transport paths and further improve thin film mobility.

[0095] In summary, this invention, through the rational design of the doping system and the control of the component ratios, can systematically optimize the overall optoelectronic performance of high-mobility indium oxide-based targets and their thin films. With a moderate increase in the total doping amount and the enhancement of the synergistic effect among the components, the material achieves significant improvements in conductivity, mobility, and transmittance.

[0096] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A high-mobility ceramic target, characterized in that, The preparation materials, by mass percentage, include the following raw materials: 98-99.5% indium oxide and 0.5-2% doped oxide; the doped oxide includes two or more of titanium oxide, zirconium oxide, gallium oxide, tantalum oxide, tungsten oxide, molybdenum oxide and rare earth oxides.

2. The high-mobility ceramic target material according to claim 1, characterized in that, The doped oxides include two of the following: titanium oxide, gallium oxide, zirconium oxide, tantalum oxide, and rare earth oxides.

3. The high-mobility ceramic target material according to claim 2, characterized in that, By mass percentage, it comprises: 0-0.5% titanium oxide, 0-1.0% gallium oxide, and 0-1.0% zirconium oxide; wherein one of the titanium oxide, gallium oxide, and zirconium oxide is 0%.

4. The high-mobility ceramic target according to claim 1, characterized in that, The doped oxide includes two or more of titanium oxide, gallium oxide, zirconium oxide and tantalum oxide, and the doped metal oxide includes one or more of tungsten oxide, molybdenum oxide and rare earth oxide.

5. The high-mobility ceramic target according to claim 4, characterized in that, By mass percentage, it includes: 0-0.5% titanium oxide, 0-0.6% gallium oxide, 0-0.5% zirconium oxide, and 0.1-0.3% doped metal oxides.

6. The high-mobility ceramic target according to claim 4, characterized in that, The doped oxides include titanium oxide, gallium oxide, and tungsten oxide; This may include titanium oxide, gallium oxide, and molybdenum oxide; This may include titanium oxide, gallium oxide, and rare earth oxides; This may include titanium oxide, zirconium oxide, and tungsten oxide; This may include titanium oxide, zirconium oxide, and molybdenum oxide; This may include titanium oxide, zirconium oxide, and rare earth oxides; This may include gallium oxide, zirconium oxide, and tungsten oxide; This may include gallium oxide, zirconium oxide, and molybdenum oxide; This may include gallium oxide, zirconium oxide, and rare earth oxides; This may include titanium oxide, gallium oxide, zirconium oxide, and tungsten oxide; This may include titanium oxide, gallium oxide, zirconium oxide, and molybdenum oxide; This may include titanium oxide, gallium oxide, zirconium oxide, and rare earth oxides; It may include titanium oxide, gallium oxide, zirconium oxide, tungsten oxide, and rare earth oxides.

7. A method for preparing the high-mobility ceramic target according to any one of claims 1 to 6, comprising: Indium oxide, doped oxide, dispersant, binder, defoamer, and deionized water are mixed to obtain a mixed slurry; the doped oxide includes two or more of titanium oxide, zirconium oxide, gallium oxide, tantalum oxide, tungsten oxide, molybdenum oxide, and rare earth oxides. The mixed slurry is spray-granulated to obtain granulated powder; The granulated powder is subjected to cold pressing and cold isostatic pressing in sequence to obtain a ceramic body. The ceramic blank is sintered to obtain a multi-element doped high-mobility ceramic target.

8. The preparation method according to claim 7, characterized in that, The pressure of the cold pressing treatment is 20~40MPa; the holding time of the cold pressing treatment is 1~3min; the pressure of the cold isostatic pressing treatment is 200~300MPa; the holding time of the cold isostatic pressing treatment is 1~60min.

9. The preparation method according to claim 7, characterized in that, The sintering process includes sequential degreasing sintering, low-temperature sintering, and high-temperature sintering; The heating rate for the degreasing sintering is 0.1~5℃ / min; the degreasing sintering temperature is 600~750℃; and the holding time for the degreasing sintering is 5~10h. The heating rate from degreasing sintering to low-temperature sintering is 0.1~5℃ / min; the temperature of low-temperature sintering is 1200~1300℃; and the holding time of low-temperature sintering is 5~10h. The heating rate from low-temperature sintering to high-temperature sintering is 0.1~5℃ / min; the high-temperature sintering temperature is 1300~1500℃, and the holding time for high-temperature sintering is 12~36h.

10. The application of the high mobility ceramic target according to any one of claims 1 to 6 or the high mobility ceramic target prepared by the preparation method according to any one of claims 7 to 9 in solar cells, thin film transistors or display devices.

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