CN112501566A - Tungsten oxide-based ceramic target material, thin film and thin film preparation process - Google Patents

Tungsten oxide-based ceramic target material, thin film and thin film preparation process Download PDF

Info

Publication number
CN112501566A
CN112501566A CN202011268699.1A CN202011268699A CN112501566A CN 112501566 A CN112501566 A CN 112501566A CN 202011268699 A CN202011268699 A CN 202011268699A CN 112501566 A CN112501566 A CN 112501566A
Authority
CN
China
Prior art keywords
tungsten oxide
mass fraction
group
doping source
powder
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202011268699.1A
Other languages
Chinese (zh)
Other versions
CN112501566B (en
Inventor
张虎
高明
杨本润
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ningbo Institute of Innovation of Beihang University
Original Assignee
Ningbo Institute of Innovation of Beihang University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ningbo Institute of Innovation of Beihang University filed Critical Ningbo Institute of Innovation of Beihang University
Priority to CN202011268699.1A priority Critical patent/CN112501566B/en
Publication of CN112501566A publication Critical patent/CN112501566A/en
Application granted granted Critical
Publication of CN112501566B publication Critical patent/CN112501566B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
    • C23C14/34—Sputtering
    • C23C14/35—Sputtering by application of a magnetic field, e.g. magnetron sputtering
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/06—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the coating material
    • C23C14/08—Oxides
    • C23C14/083—Oxides of refractory metals or yttrium
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
    • C23C14/34—Sputtering
    • C23C14/3407—Cathode assembly for sputtering apparatus, e.g. Target
    • C23C14/3414—Metallurgical or chemical aspects of target preparation, e.g. casting, powder metallurgy
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
    • C23C14/54—Controlling or regulating the coating process

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physical Vapour Deposition (AREA)
  • Compositions Of Oxide Ceramics (AREA)

Abstract

The invention relates to a tungsten oxide-based ceramic target material, a film and a film preparation process, wherein the tungsten oxide-based ceramic target material comprises tungsten oxide and doping source elements, the total mass fraction of the doping source elements is 5-50%, the doping elements of the doping source powder are selected from at least three of Ti, Mo, V, Al, Li and Zr, the mass fraction range of the Ti element is 0-15%, the mass fraction range of the Mo element is 0-15%, the mass fraction range of the V element is 0-10%, the mass fraction range of the Al element is 0-2%, the mass fraction range of the Li element is 0-2%, and the mass fraction range of the Zr element is 0-2%. The ceramic target material is used for preparing a film by a magnetron sputtering method, and comprises the steps of pre-sputtering, magnetron sputtering and annealing. The tungsten oxide-based film prepared by the method has the advantages that the resistivity of the finally prepared film is below 15.4 omega cm, and the transmissivity is above 54.2%.

Description

Tungsten oxide-based ceramic target material, thin film and thin film preparation process
Technical Field
The invention relates to a ceramic target material, in particular to a tungsten oxide-based ceramic target material, a film and a film preparation process.
Background
Tungsten trioxide is an important n-type tungsten oxide semiconductor, and has important application in the fields of gas-sensitive materials, photocatalysis, new energy and the like. Tungsten trioxide is an anode electrochromic material with excellent performance, and is oxidized by PVD sputteringThe tungsten ceramic target material is prepared into a micron and submicron photoelectric film, is compounded into a film photoelectric device, and has wide application prospect in the fields of large-screen display, high-density information storage and the like. In contrast to organic photochromic films, WO3The film has good stability and low cost. Doping certain elements into WO3The lattice defect density can be effectively improved in the crystal lattice, and the recombination process of electrons after light excitation is inhibited, so that the number of photon-generated carriers participating in the color change process is increased, and the WO is greatly improved3Photochromic properties of (1).
To prepare the above-mentioned WO3The film is prepared by using a tungsten oxide-based ceramic target material and adopting a coating method such as magnetron sputtering and the like, and has an application prospect. The magnetron sputtering process cannot leave the high-performance magnetron sputtering target, and from the aspect of coating process performance, the purity of the tungsten oxide-based ceramic target in the prior art is not high and is generally below 99.9 percent, and simultaneously, the tungsten oxide-based ceramic target does not contain doping elements or the amount of the doping elements is not in an optimal range, so the conductivity is not good, and only high-cost radio frequency sputtering equipment can be adopted; meanwhile, the crystal grain size is too large and uneven, so that the film coating process is unstable, the phenomenon of sparking and reverse sputtering is serious, the thickness of the film is uneven, the electrical property of the film is poor, the dyeing property is unstable, and the film-making cost is too high; and the density of the target is also lower, and the coating process is unstable and the performance of the coating is poor due to the too low density of the target.
Therefore, a tungsten oxide-based ceramic target with better conductivity and coating process performance and a coating preparation process matched with the tungsten oxide-based ceramic target are needed, and a tungsten oxide-based thin film with good conductivity and higher transmittance is prepared.
Disclosure of Invention
The first technical problem to be solved by the invention is to provide a tungsten oxide-based ceramic target material with better conductivity and coating process performance aiming at the current situation of the prior art.
The second technical problem to be solved by the invention is to provide a magnetron sputtering film preparation process aiming at the target material.
The third technical problem to be solved by the invention is to provide a tungsten oxide-based thin film with good conductivity and larger transmissivity.
The technical scheme adopted by the invention for solving the technical problems is as follows: the tungsten oxide-based ceramic target material comprises tungsten oxide and doping source elements, wherein the total mass fraction of the doping source elements is 5-50%, the doping elements of the doping source powder are selected from at least three of Ti, Mo, V, Al, Li and Zr, the mass fraction range of the Ti element is 0-15%, the mass fraction range of the Mo element is 0-15%, the mass fraction range of the V element is 0-10%, the mass fraction range of the Al element is 0-2%, the mass fraction range of the Li element is 0-2%, and the mass fraction range of the Zr element is 0-2%; the purity is more than 99.95 percent, the average grain size is 1-10 mu m, no obvious doped phase exists, the density is more than 98 percent, and the conductivity is more than 15S/cm.
Preferably, the total mass fraction of the doping source elements is 10 to 40%.
Further preferably, the total mass fraction of the doping source elements is 10 to 30%.
Preferably, the powder for preparing the tungsten oxide-based ceramic target is mixed powder of tungsten oxide powder and doping source powder, wherein the purity of the mixed powder is more than 99.95%, the average particle size is 500-1800 nm, and the particle size of D50 is 200-750 nm; defining M1 as the mass fraction of powder particles in a 50-100nm particle size section, M2 as the mass fraction of powder particles in a 100-400nm particle size section, M3 as the mass fraction of powder particles in a 400-700nm particle size section, M4 as the mass fraction of powder particles in a 700-1 μ M particle size section, and M5 as the mass fraction of powder particles in a particle size section larger than 1 μ M, so that the quantity relationship among M1, M2, M3, M4 and M5 meets the formula:
Figure BDA0002776931880000021
preferably, the average particle size of the mixed powder is 600-1500nm, and the particle size of D50 is 300-650 nm; further preferably, the average particle size is 800-1200nm, and the D50 particle size is 350-500 nm.
To obtain better conductivity:
preferably, the mass fraction of the Ti element is in the range of 1 to 12%, the mass fraction of the Mo element is in the range of 1 to 12%, the mass fraction of the V element is in the range of 0.5 to 10%, the mass fraction of the Al element is in the range of 0.1 to 2%, the mass fraction of the Li element is in the range of 0.1 to 2%, and the mass fraction of the Zr element is in the range of 0.1 to 2%.
Further preferably, the mass fraction of the Ti element is in the range of 5 to 10%, the mass fraction of the Mo element is in the range of 5 to 10%, the mass fraction of the V element is in the range of 1 to 10%, the mass fraction of the Al element is in the range of 0.1 to 0.8%, the mass fraction of the Li element is in the range of 0.1 to 1.5%, and the mass fraction of the Zr element is in the range of 0.2 to 2%.
Preferably, the doping source component proportion is selected from one of the following groups:
a first group: the doping source elements are Mo, Li and Zr, and the mass fraction ranges of Mo are 5-10%, Li is 0.1-1.5% and Zr is 0.2-2%;
second group: the doping source elements are Ti, Mo and Zr, and the mass fraction ranges of Ti 5-10%, Mo 5-10% and Zr 0.3-2%;
third group: the doping source elements are Li, Al and Zr, and the mass fraction ranges of Li 1-2%, Al 0.1-1% and Zr 0.3-2%;
and a fourth group: the doping source elements are Mo, V and Al, and the mass fraction ranges of Mo 5-10%, V1-10% and Al 0.1-0.8%;
and a fifth group: the doping source elements are Ti, V, Zr and Al, and the mass fraction ranges of the doping source elements are 5-10% of Ti, 1-10% of V, 0.2-2% of Zr and 0.2-0.8% of Al;
a sixth group: the doping source elements are Mo, Ti, V and Zr, the mass fraction ranges of Mo 5-10%, Ti 5-10%, V3-6% and Zr 0.5-2%,
a seventh group: the doping source elements are Mo, Li, Ti, Al and Zr, and the mass fraction ranges of Mo are 5-10%, Li is 1-2%, Ti is 5-10%, Al is 0.2-0.8% and Zr is 0.5-2%.
Further preferably, the doping source component is selected from one of the following groups according to a molar ratio:
a first group: mo: li: zr (0-10): (0-15): (0-2);
second group: ti: mo: zr (0-15): (0-10): (0-2);
third group: li: al: zr (0-15): (0-2): (0-2);
and a fourth group: mo: v: al (0-10): 0-2;
and a fifth group: ti: v: zr: al (0-15): 0-10): 0-2;
a sixth group: mo: ti: v: zr (0-10): 0-15): 0-10): 0-2);
a seventh group: mo: li: ti: al: zr (0-10), (0-15), (0-2).
Further preferably, the doping source component is selected from one of the following groups according to a molar ratio:
a first group: mo: li: zr (1-8): (2-12): (0.2-1.5)
Second group: ti: mo: zr (1-12) to (1-8) to (0.2-1.5);
third group: li: al: zr (2-12) (0.1-1.8) (0.2-1.5);
and a fourth group: mo: v: al is (1-8): (1-8): 0.1-1.8;
and a fifth group: ti: v: zr: al (1-12), (1-8), (0.2-1.5), (0.1-1.8);
a sixth group: mo: ti: v: zr (1-8): (1-12): (1-8): (0.2-1.5)
A seventh group: mo: li: ti: al: zr (1-8): (2-12): (1-12): (0.1-1.8): (0.2-1.5).
Further preferably, the doping source component is selected from one of the following groups according to a molar ratio:
a first group: mo: li: zr 5:10:1
Second group: ti: mo: zr is 10:5: 1;
third group: li: al: zr is 10:1: 1;
and a fourth group: mo: v: al is 5:5: 1;
and a fifth group: ti: v: zr: al is 10:5:1: 1;
a sixth group: mo: ti: v: zr-5: 10:5:1
A seventh group: mo: li: ti: al: zr is 5:10:10:1: 1.
The preparation process of the tungsten oxide-based film using the tungsten oxide-based ceramic target material comprises the following steps:
(a) pre-sputtering: pre-sputtering by using a tungsten oxide-based ceramic target for 5-30 min so as to remove an oxide film on the target;
(b) magnetron sputtering: depositing on a substrate, wherein the target base distance is 40-80 mm, the radio frequency power is 70-120W, the direct current power is 25-60W, the sputtering pressure is 0.2-1.0 Pa, the argon flow is 10-30 sccm, and the deposition time is 60-120 minutes to obtain a tungsten oxide base film;
(c) annealing: and annealing the tungsten oxide-based film, wherein the annealing temperature is 200-700 ℃, and the annealing time is 30-100 min.
Preferably, the pre-sputtering time of the pre-sputtering in the step (a) is 10-15 min;
preferably, the target base distance of the magnetron sputtering in the step (b) is 55-65 mm, the radio frequency power is 85-95W, the direct current power is 30-50W, the sputtering pressure is 0.5-0.7 Pa, the oxygen flow is 15-25 sccm, and the deposition time is 80-100 minutes;
preferably, the annealing temperature in the annealing in the step (c) is 350-400 ℃, and the annealing time is 50-80 min.
The tungsten oxide-based film is prepared by the tungsten oxide-based film preparation process.
Compared with the prior art, the invention has the advantages that:
1. the inventor of the invention determines a plurality of key parameters influencing the coating process performance through experiments: conductivity, average grain size, doped phase size and density; and the specific ranges of the key parameters which can improve the coating process performance are determined: comprises the types and the mass fractions of doping source elements, the average grain size of 1-10 mu m, the size of a doping phase of 0-800nm and the compactness of more than 98 percent.
2. The mixed powder used by the target material combines the high purity of the nano powder and the high bulk density of the micron powder together to obtain the high-purity wide-granularity-distribution submicron-grade doped powder which can be used for preparing the high-purity and high-conductivity tungsten oxide ceramicAnd the optimal particle size distribution formula is determined through long-term tests
Figure BDA0002776931880000041
The powder can obtain more than 1.4 g.cm-3High bulk density of (2).
3. The doping source is selected from at least three of Ti, Mo, V, Al, Li and Zr, the atomic radius of the elements is smaller than that of W, the elements can easily enter the interior of tungsten trioxide crystal lattice to form a solid solution, a low-melting-point compound can be formed, the sintering temperature is reduced, and the elements belong to photoresponsive materials, can promote the n-type conductivity of the tungsten trioxide, so that WO is created3The lattice collapse improves the atom mismatching degree and improves the conductivity.
4. According to the invention, the electrical conductivity of the prepared tungsten oxide-based ceramic target material is improved by doping the doping source, the density of holes generated by the p-type semiconductor is obviously improved by adding elements such as Ti, Mo, V, Al, Li, Zr and the like, the electrical conductivity is improved, and the tungsten oxide-based ceramic target material can be used as a sintering aid, so that the density of the ceramic is improved.
5. The average grain size of the tungsten oxide-based ceramic target material is 1-10 mu m, no obvious doped phase exists, the compactness is more than 98 percent, and the conductivity is more than 15S/cm. The ceramic target material has good conductivity, so that the film prepared by using the target material also has good conductivity, and industrial application of a P-type transparent conductive film, an electrochromic film and the like which need to use the conductivity of a tungsten oxide film becomes possible; in addition, in terms of coating process performance, the target material has high conductivity, low-cost direct current sputtering equipment can be directly adopted, and the film-making cost is reduced; the grain size is reduced, the distribution of the doped phase is uniform, the density of the target material is improved, the coating process is stable, the ignition frequency and the reverse sputtering phenomenon are reduced, the thickness of the film is more uniform, the strength of the ceramic structure is obviously improved, the target material can bear higher power density during sputtering, and faster deposition rate is obtained.
6. Because the film preparation process can greatly influence the performance of the prepared film, the invention determines the optimal corresponding film preparation process by matching the ceramic target material through long-term test, thereby greatly improving the conductivity and the transmissivity of the film.
7. The invention adopts the magnetron sputtering method to prepare the film, and the film obtained by the magnetron sputtering technology is more uniform, the performance of the equipment is very stable, the repeatability is strong, and the invention is very suitable for large-scale production; (b) because the vacuum chambers of magnetron sputtering are generally larger, a plurality of targets can be placed in the vacuum chambers, so that the targets can be used for preparing multilayer films, and the waste of time and resources caused by switching equipment again can be greatly avoided; (c) most importantly, magnetic control equipment is simple and convenient to control, and meanwhile, controllable parameters are more, so that different variables can be conveniently controlled to improve the performance of the film, and the film with more superior performance can be prepared; (d) this preparation is very suitable for preparing oxide thin films compared to other methods.
8. According to the invention, the resistivity of the finally prepared film is below 15.4 omega cm and the transmissivity is above 54.2% by the component ratio, the average grain size of the ceramic target material is 1-10 mu m, no obvious doped phase exists, the compactness is greater than 98%, the conductivity is greater than 15S/cm, and the corresponding tungsten oxide-based film preparation process is matched.
Drawings
FIG. 1 is an electron micrograph of a submicron-sized doped tungsten oxide-based final powder according to example 1 of the present invention;
FIG. 2 is an XRD spectrum of a submicron-sized doped tungsten oxide-based final powder of example 1 of the present invention;
FIG. 3 is a PSD chart of the submicron-sized doped tungsten oxide-based final powder of example 1 of the present invention;
FIG. 4 is an electron micrograph of a target material according to example 1 of the present invention;
FIG. 5 is an electron micrograph of a film of example 1 of the present invention;
FIG. 6 is an electron micrograph of a target material according to example 2 of the present invention;
FIG. 7 is an electron micrograph of a film of example 2 of the present invention.
Detailed Description
The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
The tungsten oxide powders of the following examples were prepared by the following method:
(a) preparing a premixed solution: fully dissolving pure water, an organic monomer and a cross-linking agent according to the weight ratio of 100 (7-12) to 0.7-1.2 to form a premixed solution, wherein the organic monomer is any one or combination of acrylamide, polyvinyl alcohol and polyacrylic acid, and the cross-linking agent is any one or combination of N-N' methylene bisacrylamide, polyethylene glycol and polyethylene glycol dimethacrylate.
(b) Preparing slurry: adding tungstate with the purity of more than or equal to 99.99% and doping source powder into the premixed liquid to prepare slurry with the solid content of 30-70%, adding 1-3 wt% of dispersing agent, adjusting the pH value to 8-10, performing wet ball milling dispersion, wherein the granularity of grinding balls is 0.3-10mm, the ball-to-material ratio is 1.5-4, the ball milling time is 2-20hr, the rotating speed is 150 plus 2000R/min, the tungstate is analytically pure ammonium metatungstate or ammonium paratungstate, and the dispersing agent is any one of JA281, ammonium citrate and polyvinyl alcohol
(c) And (3) gel forming: pouring the slurry into a mold, adding an initiator for crosslinking and curing, wherein the curing temperature is 40-70 ℃, the humidity is controlled at 50-70%, and drying to obtain a wet blank, wherein the initiator is any one of ammonium persulfate, azodiimidazoline propane, azodiimidazole propane hydrochloride and hydrogen peroxide;
(d) and (3) calcining: calcining the wet blank at the temperature of 750-850 ℃, wherein the temperature rise speed is not higher than 2 ℃/min, and obtaining a biscuit;
(e) crushing and granulating: pulverizing the biscuit with air flow, pre-crushing to obtain micron-sized powder, and dry-grinding for 2-20hr at 1000R/min at 100-;
(f) sieving: and sieving the primary tungsten oxide-based powder by a sieve of 40-80 meshes to obtain secondary tungsten oxide-based powder, namely the finished product powder.
The purity of the submicron-grade doped tungsten oxide-based powder prepared by the method is more than 99.95 percent, the average particle size is 500-1800 nm, and the particle size of D50 is 200-750 nm; definition M1The mass fraction of powder particles in a 50-100nm particle size range, M2Is 100-400nm granularity segment powder particle mass fraction, M3The mass fraction of powder particles in a 400-plus-700 nm particle size section, M4The mass fraction of powder particles in the 700nm-1 mu M particle size section, M5The mass fraction of powder particles in the particle size section of more than 1 mu M, M1、M2、M3、M4、M5The quantitative relationship of (a) corresponds to the formula:
Figure BDA0002776931880000061
compared with the prior art, the preparation method of the tungsten oxide powder has the advantages that:
1. the tungsten oxide-based powder combines the high purity of the nano powder and the high bulk density of the micron powder to obtain the high-purity wide-particle-size-distribution submicron-grade doped powder which can be used for preparing high-purity and high-conductivity tungsten oxide ceramics, and the optimal particle size distribution formula is determined through long-term tests.
2. The doping source is selected from at least three of Ti, Mo, V, Al, Li and Zr, the atomic radius of the elements is smaller than that of W, the elements can easily enter the interior of tungsten trioxide crystal lattice to form a solid solution, a low-melting-point compound can be formed, the sintering temperature is reduced, and the elements belong to photoresponsive materials, can promote the n-type conductivity of the tungsten trioxide, so that WO is created3Lattice collapse improves the atom mismatching degree and improves the conductivity;
3. the preparation method of the invention introduces the injection molding, uniformly distributes the doping source and the tungstate through the low-cost molding process to form a primary green body, manufactures a low-density biscuit with the doping source and the tungsten oxide uniformly distributed after roasting, performs ball milling and crushing on the biscuit, controls the ball milling process parameters, and can prepare the doped tungsten oxide powder with wide particle size distribution through proper grinding ball particle size distribution and ball-to-material ratio, thereby being applicable to the preparation of high-density doped tungsten oxide ceramics.
4. The preparation method of the invention has low cost, saves the investment of expensive equipment such as coprecipitation and the like, and has no obvious reduction of doping uniformity;
the tungsten oxide-based mixed powder can be used for preparing tungsten oxide-based ceramics by adopting a conventional ceramic forming technology, and is mainly divided into dry forming and wet forming, wherein the dry forming comprises cold isostatic pressing, hot pressing and the like, and the wet forming comprises slip casting, injection forming, pour solidification and the like. The equipment used according to the different preparation processes includes an atmospheric pressure sintering furnace, an oxygen sintering furnace, a vacuum sintering furnace, a hot pressing furnace, a hot isostatic pressing furnace and the like, and the following specific list is a few preferred preparation methods.
The doping source powder is simple substance metal, alloy, inorganic salt, organic salt or oxide of corresponding doping elements. However, because some metal elements such as Li have high activity, and enter into slurry to react with water, the danger is high, and if metal simple substances and alloys with low activity are added, the time for oxidation to oxides is long, and the ball milling time needs to be prolonged, therefore, it is further preferable that each element of the doping source is selected from corresponding inorganic salt, organic salt or oxide. Preferably, the inorganic salt of each element of the doping source is selected from corresponding nitrate, carbonate, fluoride salt or bicarbonate, etc.; the organic salt of each element of the doping source is selected from corresponding acetate, oxalate or citrate.
The solvent used in the wet ball milling in step (d) of all the following examples is any one of suitable conventional solvents such as deionized water, alcohol, acetone, kerosene, etc., and the material of the grinding ball is any one of suitable conventional grinding balls such as zirconia, corundum, agate, etc.
Example 1:(preparation by Hot isostatic pressing)
Firstly, preparing doped submicron tungsten oxide-based powder:
1) preparing raw materials: ammonium metatungstate with the purity of more than or equal to 99.99% and the doping source element components of the embodiment are Mo: li: zr5:10: 1; preparing MoO with corresponding element proportion2、Li2O、ZrO2Doping source powder with the purity more than or equal to 99.99 percent; the mass ratio of the added ammonium metatungstate to the doping source powder is 87: 13.
the doping source powder can purchase other simple substance metals, alloy inorganic salts and organic salts of corresponding elements, and the effect is similar.
2) Preparing a premixed solution, and fully dissolving pure water, organic monomer acrylamide and a cross-linking agent N 'N' -methylene bisacrylamide in a weight ratio of 100:10:1 to form the premixed solution;
3) preparing slurry: adding the pure ammonium metatungstate and the doping source powder prepared in the step 1) into the premixed liquid to prepare 50% solid content slurry, adding 2 wt% of ammonium citrate dispersant, adjusting the pH value to 9.5 by adopting tetramethylammonium hydroxide, and dispersing by adopting ball milling, wherein the average particle size of a milling ball is 1mm, and the ball-to-material ratio is 2: 1;
4) and (3) gel forming: pouring the slurry into a mold, adding an initiator ammonium persulfate to perform crosslinking curing at the curing temperature of 60 ℃ and controlling the humidity at 50%, and drying to obtain a wet blank;
5) and (3) calcining: calcining the dried wet blank at 800 ℃, wherein the heating rate is 1.5 ℃/min, and obtaining a biscuit;
6) crushing and granulating: pulverizing the biscuit with air flow to obtain micron-sized particles, and dry-grinding at 200R/min for 10hr to obtain primary tungsten oxide-based powder;
7) sieving: and (3) sieving the primary tungsten oxide-based powder by a 60-mesh standard sieve to obtain secondary tungsten oxide-based powder, namely submicron-grade doped tungsten oxide-based finished powder.
The purity of the prepared submicron-grade doped tungsten oxide-based powder is 99.99%, the mass fraction of tungsten trioxide in the powder is 85%, and the balance is a doping source oxide, wherein the doping source element components are Mo: li: zr is 5:10: 1.
The powder micrograph is shown in figure 1, the powder XRD spectrum is shown in figure 2, the powder PSD spectrum is shown in figure 3, and the average particle size of the submicron doped tungsten oxide powder prepared in the example is 1.0 mu M, the particle size of D50 is 500nm, and the particle size of M in the example is obtained from the figure1At 4%, M 220% of M 330% of, M 440% of M5Is 6%, according to the formula
Figure BDA0002776931880000081
The bulk density of the powder of this example was > 1.4 g.cm-3。
Secondly, preparing doped tungsten oxide based ceramics
1) Filling the mixed powder weighed in the step one into a sheath die in a vibration filling mode, wherein the vibration frequency is 30 Hz;
2) vacuum degassing is carried out on the sheath, the degassing temperature is 500 ℃, and the temperature is kept for 3 h;
3) and (3) carrying out hot isostatic pressing treatment on the clad: the pressure is 100MPa, the sintering temperature is 900 ℃, the heat preservation time is 2.5h, the heating speed is 1.5 ℃/min, and the pressure source is nitrogen;
4) cooling, removing pressure, removing the sheath and obtaining a sintered blank;
5) and (4) machining or not machining to the designed size according to the requirement to obtain the target finished product.
The relative density is measured by a drainage method to be 99.5 percent, the average grain size is 3 mu m, the doping elements enter the ceramic crystal lattice, no obvious second phase exists, the conductivity of the ceramic body is measured by cutting samples to be 25S/cm, the microstructure is uniform, and the micro-anoxic state is achieved.
An electron micrograph of the ceramic prepared in this example is shown in FIG. 4.
Preparation of tungsten oxide-based thin film
All targets must be pre-sputtered for 15min before deposition experiments, and oxide films on the targets are removed.
The adopted coating method is magnetron sputtering, the radio frequency power is 90W, the sputtering pressure is 0.6Pa, the oxygen flow is 20sccm, and the deposition time is 90 minutes. Glass slides were used as substrates with a target base distance of 60 mm. And after the glow discharge is stable, setting experimental parameters, starting the baffle plate to prepare the sample, and taking out the film sample after the deposition is finished and the film sample is cooled to room temperature. And then putting the deposited tungsten oxide-based film into a high-temperature sintering furnace for annealing, wherein the annealing temperature is 400 ℃, and the annealing time is 1 h.
The obtained resistivity was 12.8 Ω · cm, the transmittance was 57.9%, and the photoelectric properties were good.
An electron micrograph of the tungsten oxide-based thin film prepared in this example is shown in FIG. 5.
Example 2:(preparation by Hot Press Molding method)
Firstly, preparing doped submicron tungsten oxide-based powder:
this example is the same as example 1.
Secondly, preparing doped tungsten oxide based ceramics
1) Dividing the mixed powder prepared in the first step into 3 parts, loading the 3 parts into a hot-pressing die, compacting after each part is added, and pre-pressing the die after all the parts are filled: the pressure is 1MPa, and the time is 2 hours;
2) after the pre-pressurization is finished, the mould is subjected to integral degassing;
3) hot-pressing and sintering: the pressure is 10MPa, the vacuum degree is 7Pa, the sintering temperature is 700 ℃, the heat preservation time is 2h, and the temperature rise speed is 1 ℃/min;
4) after the heat preservation is finished, removing the pressure, and taking out the sintered blank;
5) and machining according to requirements to obtain a ceramic finished product.
The relative density is measured by a drainage method to be 99.3 percent, the average grain size is 3.2 mu m, the doping elements enter the ceramic crystal lattice, no obvious second phase exists, the conductivity of the ceramic body is measured by cutting samples to be 24S/cm, the microstructure is uniform, and the micro-anoxic state is achieved.
An electron micrograph of the ceramic prepared in this example is shown in FIG. 6.
Preparation of tungsten oxide-based thin film
This example is the same as example 1.
The obtained tungsten oxide-based thin film has the resistivity of 12.5 omega cm, the transmissivity of 58.0 percent and better photoelectric performance.
An electron micrograph of the tungsten oxide-based thin film of this example is shown in FIG. 7.
Example 3:(preparation by Hot isostatic pressing)
Firstly, preparing doped submicron tungsten oxide-based powder:
the difference between the present example and example 1 is that the mass fraction of the tungsten component in the powder calculated by tungsten oxide is 85%, the mass fraction of the doping source is 15%, and the doping source component is, in terms of mole ratio, Ti: mo: zr is 10:5: 1.
Secondly, preparing doped tungsten oxide based ceramics
The procedure is the same as that in example 1, the obtained tungsten oxide-based ceramic has a relative density of 98.5% measured by a drainage method, an average grain size of 4.5 μm, doping elements enter a ceramic lattice, no obvious second phase exists, and the conductivity of the ceramic body is 15S/cm measured by cutting a sample.
Preparation of tungsten oxide-based thin film
All targets must be pre-sputtered for 30min before deposition experiments, and oxide films on the targets are removed.
The adopted coating method is magnetron sputtering, the radio frequency power is 120W, the direct current power is 60W, the sputtering pressure is 1Pa, the argon flow is 30sccm, and the deposition time is 120 minutes. Glass slides were used as substrates with a target base distance of 80 mm.
And after the glow discharge is stable, setting experimental parameters, starting the baffle plate to prepare the sample, and taking out the film sample after the deposition is finished and the film sample is cooled to room temperature. And then putting the deposited tungsten oxide-based film into a high-temperature sintering furnace for annealing, wherein the annealing temperature is 700 ℃, and the annealing time is 100 min.
The obtained tungsten oxide-based thin film has the resistivity of 15.4 omega cm, the transmissivity of 54.2 percent and better photoelectric performance.
Example 4:(preparation by Hot isostatic pressing)
Firstly, preparing doped submicron tungsten oxide-based powder:
this example is the same as example 3.
Secondly, preparing doped tungsten oxide based ceramics
In the same procedure as in example 3, the obtained tungsten oxide-based ceramic has a relative density of 98.4% as measured by a drainage method, an average grain size of 4.3 μm, a doping element entering a ceramic lattice, no obvious second phase existing, and a ceramic body conductivity of 16S/cm as measured by cutting a sample.
Preparation of tungsten oxide-based thin film
All targets must be pre-sputtered for 6min before deposition experiments, and oxide films on the targets are removed.
The adopted coating method is magnetron sputtering, the radio frequency power is 70W, the direct current power is 25W, the sputtering pressure is 0.2Pa, the oxygen flow is 10sccm, and the deposition time is 60 minutes. Glass slides were used as substrates with a target base distance of 40 mm.
And after the glow discharge is stable, setting experimental parameters, starting the baffle plate to prepare the sample, and taking out the film sample after the deposition is finished and the film sample is cooled to room temperature. And then putting the deposited tungsten oxide-based film into a high-temperature sintering furnace for annealing, wherein the annealing temperature is 200 ℃, and the annealing time is 30 min.
The obtained tungsten oxide-based thin film has the resistivity of 14.8 omega cm, the transmissivity of 55.1 percent and better photoelectric performance.
Example 5:(preparation by gel casting)
Firstly, preparing doped submicron tungsten oxide-based powder:
1) preparing raw materials: preparing ammonium metatungstate with the purity of more than or equal to 99.99 percent, wherein the doping source element components of the embodiment are Ti: mo: zr is 10:1: 1; preparing titanium oxide, molybdenum oxide and zirconium oxide doping source powder with corresponding element proportion, wherein the purity is more than or equal to 99.999 percent; the mass ratio of the added ammonium metatungstate to the doping source powder is 92.2: 7.8.
the doping source powder can purchase other simple substance metals, alloy inorganic salts and organic salts of corresponding elements, and the effect is similar.
2) Preparing a premixed solution, namely mixing pure water and an organic monomer which is the combination of polyvinyl alcohol and polyacrylic acid, wherein the ratio of the polyvinyl alcohol to the polyacrylic acid is 1:1, and a cross-linking agent which is the combination of polyethylene glycol and polyethylene glycol dimethacrylate, wherein the ratio of the polyethylene glycol to the polyethylene glycol dimethacrylate is 1: 1; fully dissolving pure water, organic monomer and cross-linking agent in a weight ratio of 100:11:1.1 to form a premixed solution;
3) preparing slurry: adding the pure ammonium metatungstate and the doping source powder prepared in the step 1) into the premixed liquid to prepare slurry with the solid content of 45%, adding 0.05 wt% of ammonium citrate dispersant, adjusting the pH value to 10 by adopting ammonia water, and performing ball milling dispersion, wherein the average particle size of a milling ball is 1.5mm, and the ball-to-material ratio is 2: 1;
4) and (3) gel forming: pouring the slurry into a mold, adding an initiator azodiimidazoline propane for crosslinking and curing, controlling the curing temperature at 60 ℃ and the humidity at 60%, and drying to obtain a wet blank;
5) and (3) calcining: calcining the dried wet blank at 750 ℃ at the heating rate of 1.0 ℃/min to obtain a biscuit;
6) crushing and granulating: jet milling the biscuit, pre-milling the biscuit into micron-sized particles, and dry-milling the micron-sized particles at 1000R/min for 2hr to obtain primary tungsten oxide-based powder;
7) sieving: and (3) sieving the primary tungsten oxide-based powder by a 60-mesh standard sieve to obtain secondary tungsten oxide-based powder, namely submicron-grade doped tungsten oxide-based finished powder.
The purity of the prepared submicron-grade doped tungsten oxide-based powder is 99.99%, the mass fraction of tungsten trioxide in the powder is 90%, and the balance is doping source oxide, wherein the doping source element components are Ti: mo: zr is 10:1: 1.
The submicron doped tungsten oxide powder prepared in this example has an average particle size of 0.8 μ M, the particle size of D50 is 400nm, and M in this example1At 5%, M235% of M315% of M435% of M5Is 10%, and meets the formula
Figure BDA0002776931880000111
The bulk density of the powder of this example was > 1.4 g.cm-3。
Secondly, preparing doped tungsten oxide based ceramics
1) Preparing a premixed solution: fully dissolving pure water, an organic monomer and a cross-linking agent in a weight ratio of 100:12:1 to form a premixed solution; the organic monomer in this example is a combination of polyvinyl alcohol and polyacrylic acid, and the ratio of polyvinyl alcohol: the weight ratio of polyacrylic acid is 1: 1; the cross-linking agent is the combination of polyethylene glycol and polyethylene glycol dimethacrylate, and the ratio of polyethylene glycol: the weight ratio of the polyethylene glycol dimethacrylate is 1: 1;
2) preparing high-fluidity slurry: adding 0.03 wt% of ammonium citrate which has no residue after sintering as a dispersing agent into the premixed solution; and (2) weighing the mixed powder prepared in the first step by using a digital electronic balance, evenly dividing the powder into two parts, sequentially adding the two parts into the premixed liquid, placing the premixed liquid into a ball mill, and carrying out ball milling for 40 hours, wherein zirconia balls are used as ball milling media for the slurry in the ball mill. Preparing slurry with the powder volume content of 45% by ball milling, namely, the solid phase content of mixed powder in the slurry is 45%, and adjusting the pH value of the slurry to 9.5 by using pure ammonia water to obtain high-fluidity slurry with the viscosity of about 60-65mPa & s;
3) preparing a biscuit: 0.25 wt% of polyethylene glycol organic defoaming agent and 0.2 wt% of azodiimidazoline propane initiator are stirred and degassed for 15 minutes in a casting system under negative pressure, and the mixture is cast into a mold.
Heating and drying for the first time: after the mould is poured, the mould filled with the sizing agent is placed in an air oven with the temperature of 80 ℃ and the humidity of 70 percent, and the gel monomer is promoted to be crosslinked and cured at constant temperature.
And (3) secondary drying: demoulding the cured wet blank, and drying the wet blank for 30 hours at the temperature of 50 ℃ and the humidity of 65 percent to obtain a tungsten oxide biscuit with high strength and no defects;
4) degumming biscuit: heating the biscuit in a flowing air furnace for degumming, firstly, heating the furnace to a first gradient temperature of 250 ℃, heating at a speed of 0.8 ℃/min, and keeping the temperature for 3 hours;
then the temperature is increased to 600 ℃ of the second gradient temperature, the heat preservation time is 5 hours, and the temperature increasing speed is 0.9 ℃/min. And cooling to room temperature along with the furnace to obtain the degummed blank.
5) And (3) sintering: placing the degummed blank in a ventilation air furnace for sintering, firstly heating the furnace to 700 ℃ of first gradient temperature, heating up at a speed of 1 ℃/min, keeping the temperature for 2 hours, then heating up to 1000 ℃, keeping the temperature for 10 hours at a speed of 0.6 ℃/min, and cooling to room temperature along with the furnace.
6) And machining according to requirements to obtain a ceramic finished product.
The obtained tungsten oxide-based ceramic has the relative density of 98.2 percent and the average grain size of 5 mu m measured by a drainage method, doping elements enter a ceramic crystal lattice, no obvious second phase exists, and the conductivity of the ceramic body is 22S/cm measured by cutting samples.
Preparation of tungsten oxide-based thin film
All targets must be pre-sputtered for 12min before deposition experiments to remove the oxide film on the targets.
The adopted coating method is magnetron sputtering, the radio frequency power is 82W, the direct current power is 37W, the sputtering pressure is 0.3Pa, the oxygen flow is 16sccm, and the deposition time is 78 minutes. Glass slides were used as substrates with a target base distance of 45 mm.
And after the glow discharge is stable, setting experimental parameters, starting the baffle plate to prepare the sample, and taking out the film sample after the deposition is finished and the film sample is cooled to room temperature. And then putting the deposited tungsten oxide-based film into a high-temperature sintering furnace for annealing, wherein the annealing temperature is 256 ℃ and the annealing time is 46 min.
The obtained tungsten oxide-based thin film has the resistivity of 14.3 omega cm, the transmissivity of 55.3 percent and better photoelectric performance.
Example 6:(preparation by Hot Press Molding method)
Firstly, preparing doped submicron tungsten oxide-based powder:
this example is the same as example 5.
Secondly, preparing doped tungsten oxide based ceramics
1) Weighing the submicron-grade doped tungsten oxide-based finished product powder prepared in the step one, dividing the powder into 2 parts, filling the powder into a proper hot-pressing die, compacting after each part is added, and pre-pressing the die after all parts are filled: the pressure is 2MPa, and the time is 2 hours;
2) carrying out integral degassing on the die;
3) hot-pressing and sintering: the pressure is 100MPa, the vacuum degree is 10Pa, the sintering temperature is 1000 ℃, the heat preservation time is 3h, and the temperature rise speed is 1 ℃/min;
4) cooling and removing pressure after the heat preservation time is reached; taking the sheath out of the furnace chamber, removing the sheath and taking out the sintered blank;
5) and cleaning the sintered blank, and machining to a designed size to obtain a ceramic target finished product.
The obtained tungsten oxide-based ceramic has the relative density of 98.3 percent and the average grain size of 4.8 mu m measured by a drainage method, doping elements enter a ceramic crystal lattice, no obvious second phase exists, and the resistivity of the ceramic body measured by cutting samples is 21S/cm.
Preparation of tungsten oxide-based thin film
This example is the same as example 3.
The obtained tungsten oxide-based thin film has the resistivity of 15.1 omega cm, the transmissivity of 54.9 percent and better photoelectric performance.
An electron micrograph of the tungsten oxide-based thin film of this example is shown in the figure.
Example 7:(preparation by Cold isostatic pressing)
Firstly, preparing doped submicron tungsten oxide-based powder:
this example differs from example 5 in that the doping sources used were molybdenum oxide, vanadium oxide and aluminum oxide, and the doping source components of the preparation step were, in terms of mole ratios, Mo: v: al is 5:5: 1;
secondly, preparing doped tungsten oxide based ceramics
1) Weighing the mixed powder prepared in the first step by using a digital electronic balance, and adding deionized water with 0.8 time of volume to prepare secondary slurry with 56% vol solid phase fraction;
2) spray drying:
(2.1) adding a2 wt% aqueous solution of a binder into the secondary slurry, wherein the binder consists of polyvinyl alcohol and polycarbonate in a ratio of 3:1, the addition amount of the aqueous solution of the binder is 2% of the total weight of the slurry, and stirring for 10 hours to disperse;
(2.2) carrying out spray drying on the slurry at the inlet temperature of 300 ℃ and the outlet temperature of 110 ℃ to obtain secondary powder;
(2.3) sieving the powder with a 60-mesh sieve; the obtained secondary powder has a flowability parameter of 1.50g cm-3, and has an average particle diameter of 5 μm and a D50 particle diameter of 2 μm.
3) Putting the mixed powder prepared in the step 2) into a cold isostatic pressing die, and compacting under the vibration frequency of 10Hz to reach the tap density of 2.2 g.cm < -3 >;
4) the die is sent into a cold isostatic pressing chamber for pressing, the pressure is 150MPa, the pressure maintaining time is 30min, and the green body is taken out after the pressing and the demolding;
5) degumming biscuit: heating the biscuit in a flowing air furnace for degumming, firstly, heating the furnace to a first gradient temperature of 250 ℃, heating at a speed of 0.5 ℃/min, and keeping the temperature for 4 hours; then the temperature is increased to 600 ℃ of the second gradient temperature, the heat preservation time is 6 hours, and the temperature increasing speed is 0.8 ℃/min. And cooling to room temperature along with the furnace to obtain the degummed blank.
6) And (3) sintering: placing the degummed blank in a ventilation air furnace for sintering, firstly heating the furnace to 600 ℃ of a first gradient temperature, heating at a speed of 1 ℃/min, keeping the temperature for 2 hours, then heating to 1000 ℃, keeping the temperature for 10 hours at a speed of 0.6 ℃/min, and cooling to room temperature along with the furnace.
7) And machining according to requirements to obtain a ceramic finished product.
The obtained ceramic target finished product has the relative density of 98.0 percent, the average grain size of 3.5 mu measured by a drainage method, the doping elements enter a ceramic crystal lattice, no obvious second phase exists, and the bulk conductivity is 18S/cm.
Preparation of tungsten oxide-based thin film
This example is the same as example 5.
The obtained tungsten oxide-based thin film has the resistivity of 14.4 omega cm, the transmissivity of 55.6 percent and better photoelectric performance.
Example 8:(preparation by gel casting)
Firstly, preparing doped submicron tungsten oxide-based powder:
this example is the same as example 7.
Secondly, preparing doped tungsten oxide based ceramics
This example is the same as example 5.
The obtained ceramic target finished product has the relative density of 97.8 percent and the average grain size of 3.7 mu m measured by a drainage method, the doping elements enter the ceramic crystal lattice, no obvious second phase exists, and the bulk conductivity is 19S/cm
Preparation of tungsten oxide-based thin film
This example is the same as example 4.
The obtained tungsten oxide-based thin film has the resistivity of 14.9 omega cm, the transmittance of 55.4 percent and better photoelectric performance.
Example 9:(preparation by Hot isostatic pressing)
Firstly, preparing doped submicron tungsten oxide-based powder:
1) preparing raw materials: preparing ammonium metatungstate with the purity of more than or equal to 99.99 percent, wherein the doping source element components of the embodiment are Ti: v: zr: al is 10:5:1: 1; preparing titanium oxide, molybdenum oxide and zirconium oxide doping source powder with corresponding element proportion, wherein the purity is more than or equal to 99.999 percent; the mass ratio of the added ammonium metatungstate to the doping source powder is 87: 13
The doping source powder can purchase other simple substance metals, alloy inorganic salts and organic salts of corresponding elements, and the effect is similar.
2) Preparing a premixed solution, and fully dissolving pure water, organic monomer polyacrylic acid and cross-linking agent polyethylene glycol in a weight ratio of 100:12:1.2 to form the premixed solution;
3) preparing slurry: adding the pure ammonium metatungstate prepared in the step 1) and the doping source powder into the premixed solution to prepare slurry with the solid content of 50%, adding 0.1 wt% of JA281 dispersant, adjusting the pH value to 9.5 by using ammonia water, and performing ball milling dispersion, wherein the average particle size of grinding balls is 2mm, and the ball-to-material ratio is 2: 1;
4) and (3) gel forming: pouring the slurry into a mold, adding an initiator azodimidepropane hydrochloride for crosslinking and curing, wherein the curing temperature is 65 ℃, the humidity is controlled at 70%, and drying to obtain a wet blank;
5) and (3) calcining: calcining the dried wet blank at 700 ℃, and heating at a speed of 1.0 ℃/min to obtain a biscuit;
6) crushing and granulating: pulverizing the biscuit with air flow to obtain primary pulverized micrometer powder, and dry-grinding at 500R/min for 10hr to obtain primary tungsten oxide-based powder;
7) sieving: and (3) sieving the primary tungsten oxide-based powder by a 60-mesh standard sieve to obtain secondary tungsten oxide-based powder, namely submicron-grade doped tungsten oxide-based finished powder.
The purity of the prepared submicron-grade doped tungsten oxide-based powder is 99.99%, the mass fraction of tungsten trioxide in the powder is 85%, and the balance is doping source oxide, wherein the doping source element components are Ti: v: zr: al is 10:5:1: 1.
The submicron doped tungsten oxide powder prepared in this example has an average particle size of 1.0 μ M, the particle size of D50 is 550nm, and M in this example1At 5%, M235% of M 320% of M425% of M5Is 15%, and meets the formula
Figure BDA0002776931880000151
The bulk density of the powder of this example was > 1.4 g.cm-3。
Secondly, preparing doped tungsten oxide-based ceramic:
1) filling the mixed powder weighed in the step one into a sheath die in a vibration filling mode, wherein the vibration frequency is 50 Hz;
2) vacuum degassing is carried out on the sheath, wherein the degassing temperature is 450 ℃ in a vacuum furnace, and the temperature is kept for 5 hours;
3) and (3) carrying out hot isostatic pressing treatment on the clad: the pressure is 50MPa, the sintering temperature is 800 ℃, the heat preservation time is 1h, and the heating rate is 1.5 ℃/min
4) Cooling after the heat preservation time is reached, removing the pressure, taking the sheath out of the furnace chamber, removing the sheath, and taking out the sintered blank;
5) and cleaning the sintered blank, and machining to a designed size to obtain a ceramic target finished product. The obtained tungsten oxide-based ceramic has the relative density of 98.5 percent and the average grain size of 4 mu m measured by a drainage method, doping elements enter a ceramic crystal lattice, no obvious second phase exists, and the conductivity of the ceramic body is 20S/cm measured by cutting samples.
Preparation of tungsten oxide-based thin film
All targets must be pre-sputtered for 10min before deposition experiments to remove the oxide film on the targets.
The adopted coating method is magnetron sputtering, the radio frequency power is 86W, the direct current power is 31W, the sputtering pressure is 0.5Pa, the argon flow is 16sccm, and the deposition time is 85 minutes. Glass slides were used as substrates with a target base distance of 56 mm.
And after the glow discharge is stable, setting experimental parameters, starting the baffle plate to prepare the sample, and taking out the film sample after the deposition is finished and the film sample is cooled to room temperature. And then putting the deposited tungsten oxide-based film into a high-temperature sintering furnace for annealing, wherein the annealing temperature is 350 ℃, and the annealing time is 52 min.
The obtained tungsten oxide-based thin film has the resistivity of 13.7 omega cm, the transmissivity of 56.4 percent and better photoelectric performance.
Example 10:(preparation by gel casting)
Firstly, preparing doped submicron tungsten oxide-based powder:
this example is the same as example 9.
Secondly, preparing doped tungsten oxide-based ceramic:
1) preparing a premixed solution: fully dissolving pure water, an organic monomer and a cross-linking agent in a weight ratio of 100:8:1 to form a premixed solution; the organic monomer of this example is N-vinylpyrrolidone; the cross-linking agent is polyethylene glycol;
2) preparing high-fluidity slurry: adding 0.02 wt% of JA281 which is not left after sintering and is taken as a dispersant into the premixed liquid; weighing the mixed powder prepared in the first step by using a digital electronic balance, dividing the powder into 50%, 33% and 17%, sequentially adding the three parts into the premixed liquid, placing the premixed liquid into a ball mill, and carrying out ball milling for 40 hours, wherein zirconia balls are used as ball milling media for the slurry in the ball mill. Preparing slurry with the powder volume content of 70% by ball milling, namely, the solid phase content of mixed powder in the slurry is 70%, and adjusting the pH value of the slurry to 8.5 by using pure ammonia water to obtain high-fluidity slurry with the viscosity of about 60-65mPa & s;
3) preparing a biscuit: mixing 0.25 wt% of polyethylene glycol and n-octanol with an organic defoamer, wherein the ratio of polyethylene glycol: the mass ratio of n-octanol is 1:3, and 0.2 wt% of azodiimidazoline propane initiator, stirring and degassing for 15 minutes in a casting system under negative pressure, and casting into a mold.
Heating and drying for the first time: after the mould is poured, the mould filled with the slurry is placed in an air oven with the temperature of 65 ℃, the humidity is less than 5 percent, and the gel monomer is promoted to be crosslinked and cured at constant temperature.
And (3) secondary drying: demoulding the cured wet blank, and drying the wet blank for 30 hours at the temperature of 60 ℃ and the humidity of 70 percent to obtain a tungsten oxide biscuit with high strength and no defects;
4) degumming biscuit: heating the biscuit in a flowing air furnace for degumming, firstly, heating the furnace to a first gradient temperature of 120 ℃, heating at a speed of 0.8 ℃/min, and keeping the temperature for 3 hours;
then the temperature is increased to the second gradient temperature of 400 ℃, the heat preservation time is 10 hours, and the temperature increasing speed is 0.5 ℃/min. And cooling to room temperature along with the furnace to obtain the degummed blank.
5) And (3) sintering: placing the degummed blank in a ventilation air furnace for sintering, firstly heating the furnace to the first gradient temperature of 750 ℃, heating up to the speed of 0.5 ℃/min, keeping the temperature for 5 hours, then heating up to 950 ℃, keeping the temperature for 15 hours, heating up to the speed of 0.5 ℃/min, and cooling to the room temperature along with the furnace.
6) And (5) processing by a cleaning machine to obtain a ceramic finished product.
The obtained tungsten oxide-based ceramic has the relative density of 98.4 percent and the average grain size of 4 mu m measured by a drainage method, doping elements enter a ceramic crystal lattice, no obvious second phase exists, and the conductivity of the ceramic body is 21S/cm measured by cutting samples.
Preparation of tungsten oxide-based thin film
This example is the same as example 9.
The obtained tungsten oxide-based thin film has the resistivity of 13.8 omega cm, the transmittance of 57.0 percent and better photoelectric performance.
Example 11:(preparation by Hot isostatic pressing)
Firstly, preparing doped submicron tungsten oxide-based powder:
the difference between this example and example 9 is that molybdenum oxide, titanium oxide, vanadium oxide and zirconium oxide are used as the doping source, the mass fraction of tungsten calculated as tungsten oxide is 80%, the mass fraction of the doping source is 20%, and the doping source component in the preparation step is Mo: ti: v: zr is 5:10:5: 1;
secondly, preparing doped tungsten oxide based ceramics
1) Filling the mixed powder weighed in the step one into a sheath die in a vibration filling mode, wherein the vibration frequency is 50 Hz;
2) vacuum degassing is carried out on the sheath, wherein the degassing temperature is 450 ℃ in a vacuum furnace, and the temperature is kept for 5 hours;
3) and (3) carrying out hot isostatic pressing treatment on the clad: the pressure is 50MPa, the sintering temperature is 800 ℃, the heat preservation time is 1h, and the heating rate is 1.5 ℃/min
4) Cooling after the heat preservation time is reached, removing the pressure, taking the sheath out of the furnace chamber, removing the sheath, and taking out the sintered blank;
5) and cleaning the sintered blank, machining to a designed size, actually measuring the relative density of the obtained ceramic target finished product by a drainage method to be 98.3 percent, wherein the average grain size is 3.5 mu m, the doping elements enter a ceramic crystal lattice, no obvious second phase exists, and the bulk conductivity is 21S/cm.
Preparation of tungsten oxide-based thin film
This example is the same as example 9.
The obtained tungsten oxide-based thin film has the resistivity of 13.4 omega cm, the transmissivity of 56.8 percent and better photoelectric performance.
Example 12:(preparation by gel casting)
Firstly, preparing doped submicron tungsten oxide-based powder:
this example is the same as example 11.
Secondly, preparing doped tungsten oxide based ceramics
This example is the same as example 10.
The obtained ceramic target finished product has the relative density of 98.4 percent, the average grain size of 3.8 mu m, doping elements enter ceramic crystal lattices, no obvious second phase exists, and the bulk conductivity is 21S/cm, which is measured by a drainage method.
Preparation of tungsten oxide-based thin film
This example is the same as example 1.
The obtained tungsten oxide-based thin film has the resistivity of 13.0 omega cm, the transmissivity of 57.6 percent and better photoelectric performance.

Claims (10)

1. A tungsten oxide-based ceramic target material comprises tungsten oxide and doping source elements, and is characterized in that: the total mass fraction of the doping source elements is 5-50%, the doping elements of the doping source powder are selected from at least three of Ti, Mo, V, Al, Li and Zr, the mass fraction of the Ti element ranges from 0% to 15%, the mass fraction of the Mo element ranges from 0% to 15%, the mass fraction of the V element ranges from 0% to 10%, the mass fraction of the Al element ranges from 0% to 2%, the mass fraction of the Li element ranges from 0% to 2%, and the mass fraction of the Zr element ranges from 0% to 2%; the purity is more than 99.95 percent, the average grain size is 1-10 mu m, no obvious doped phase exists, the density is more than 98 percent, and the conductivity is more than 15S/cm.
2. The tungsten oxide-based ceramic target according to claim 1, wherein: the powder for preparing the tungsten oxide-based ceramic target is mixed powder of tungsten oxide powder and doping source powder, wherein the purity of the mixed powder is more than 99.95 percent, the average grain diameter is 500-1800 nm, and the grain diameter of D50 is 200-750 nm; defining M1 as the mass fraction of powder particles in a 50-100nm particle size section, M2 as the mass fraction of powder particles in a 100-400nm particle size section, M3 as the mass fraction of powder particles in a 400-700nm particle size section, M4 as the mass fraction of powder particles in a 700-1 μ M particle size section, and M5 as the mass fraction of powder particles in a particle size section larger than 1 μ M, so that the quantity relationship among M1, M2, M3, M4 and M5 meets the formula:
Figure FDA0002776931870000011
3. the tungsten oxide-based ceramic target according to claim 1, wherein: the mass fraction of the Ti element is in the range of 1-12%, the mass fraction of the Mo element is in the range of 1-12%, the mass fraction of the V element is in the range of 0.5-10%, the mass fraction of the Al element is in the range of 0.1-2%, the mass fraction of the Li element is in the range of 0.1-2%, and the mass fraction of the Zr element is in the range of 0.1-2%.
4. The tungsten oxide-based ceramic target according to claim 1, wherein: the component proportion of the doping source is selected from one of the following groups:
a first group: the doping source elements are Mo, Li and Zr, and the mass fraction ranges of Mo are 5-10%, Li is 0.1-1.5% and Zr is 0.2-2%;
second group: the doping source elements are Ti, Mo and Zr, and the mass fraction ranges of Ti 5-10%, Mo 5-10% and Zr 0.3-2%;
third group: the doping source elements are Li, Al and Zr, and the mass fraction ranges of Li 1-2%, Al 0.1-1% and Zr 0.3-2%;
and a fourth group: the doping source elements are Mo, V and Al, and the mass fraction ranges of Mo 5-10%, V1-10% and Al 0.1-0.8%;
and a fifth group: the doping source elements are Ti, V, Zr and Al, and the mass fraction ranges of the doping source elements are 5-10% of Ti, 1-10% of V, 0.2-2% of Zr and 0.2-0.8% of Al;
a sixth group: the doping source elements are Mo, Ti, V and Zr, the mass fraction ranges of Mo 5-10%, Ti 5-10%, V3-6% and Zr 0.5-2%,
a seventh group: the doping source elements are Mo, Li, Ti, Al and Zr, and the mass fraction ranges of Mo are 5-10%, Li is 1-2%, Ti is 5-10%, Al is 0.2-0.8% and Zr is 0.5-2%.
5. The tungsten oxide-based ceramic target according to claim 1, wherein: the doping source component is selected from one of the following groups according to a molar ratio:
a first group: mo: li: zr (0-10): (0-15): (0-2);
second group: ti: mo: zr (0-15): (0-10): (0-2);
third group: li: al: zr (0-15): (0-2): (0-2);
and a fourth group: mo: v: al (0-10): 0-2;
and a fifth group: ti: v: zr: al (0-15): 0-10): 0-2;
a sixth group: mo: ti: v: zr (0-10): 0-15): 0-10): 0-2);
a seventh group: mo: li: ti: al: zr (0-10), (0-15), (0-2).
6. The tungsten oxide-based ceramic target according to claim 1, wherein: the doping source component is selected from one of the following groups according to a molar ratio:
a first group: mo: li: zr (1-8): (2-12): (0.2-1.5)
Second group: ti: mo: zr (1-12) to (1-8) to (0.2-1.5);
third group: li: al: zr (2-12) (0.1-1.8) (0.2-1.5);
and a fourth group: mo: v: al is (1-8): (1-8): 0.1-1.8;
and a fifth group: ti: v: zr: al (1-12), (1-8), (0.2-1.5), (0.1-1.8);
a sixth group: mo: ti: v: zr (1-8): (1-12): (1-8): (0.2-1.5)
A seventh group: mo: li: ti: al: zr (1-8): (2-12): (1-12): (0.1-1.8): (0.2-1.5).
7. A process for preparing a tungsten oxide-based thin film using the tungsten oxide-based ceramic target material according to any one of claims 1 to 6, characterized in that:
(a) pre-sputtering: pre-sputtering by using a tungsten oxide-based ceramic target for 5-30 min so as to remove an oxide film on the target;
(b) magnetron sputtering: depositing on a substrate, wherein the target base distance is 40-80 mm, the radio frequency power is 70-120W, the direct current power is 25-60W, the sputtering pressure is 0.2-1.0 Pa, the argon flow is 10-30 sccm, and the deposition time is 60-120 minutes to obtain a tungsten oxide base film;
(c) annealing: and annealing the tungsten oxide-based film, wherein the annealing temperature is 200-700 ℃, and the annealing time is 30-100 min.
8. The process for preparing a tungsten oxide-based thin film according to claim 7, wherein: the target base distance of the magnetron sputtering in the step (b) is 55-65 mm, the radio frequency power is 85-95W, the direct current power is 30-50W, the sputtering pressure is 0.5-0.7 Pa, the oxygen flow is 15-25 sccm, and the deposition time is 80-100 minutes.
9. The process for preparing a tungsten oxide-based thin film according to claim 7, wherein: the annealing temperature of the annealing in the step (c) is 350-400 ℃, and the annealing time is 50-80 min.
10. A tungsten oxide-based thin film produced using the production process according to any one of claims 7 to 9.
CN202011268699.1A 2020-11-13 2020-11-13 Tungsten oxide-based ceramic target material, thin film and thin film preparation process Active CN112501566B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011268699.1A CN112501566B (en) 2020-11-13 2020-11-13 Tungsten oxide-based ceramic target material, thin film and thin film preparation process

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011268699.1A CN112501566B (en) 2020-11-13 2020-11-13 Tungsten oxide-based ceramic target material, thin film and thin film preparation process

Publications (2)

Publication Number Publication Date
CN112501566A true CN112501566A (en) 2021-03-16
CN112501566B CN112501566B (en) 2023-03-14

Family

ID=74957501

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011268699.1A Active CN112501566B (en) 2020-11-13 2020-11-13 Tungsten oxide-based ceramic target material, thin film and thin film preparation process

Country Status (1)

Country Link
CN (1) CN112501566B (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010180449A (en) * 2009-02-04 2010-08-19 Sumitomo Metal Mining Co Ltd Target material of composite tungsten oxide, and method for manufacturing the same
CN102423802A (en) * 2011-12-20 2012-04-25 宁波江丰电子材料有限公司 Preparation method of highly-pure cobalt target
CN109021962A (en) * 2018-08-30 2018-12-18 合肥工业大学 A kind of crystalline state tungstic acid/titanium doped amorphous state tungsten oxide nanometer linear array and preparation method thereof
CN110357626A (en) * 2019-07-26 2019-10-22 中国建筑材料科学研究总院有限公司 Doped tungsten oxide target and preparation method thereof

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010180449A (en) * 2009-02-04 2010-08-19 Sumitomo Metal Mining Co Ltd Target material of composite tungsten oxide, and method for manufacturing the same
CN102423802A (en) * 2011-12-20 2012-04-25 宁波江丰电子材料有限公司 Preparation method of highly-pure cobalt target
CN109021962A (en) * 2018-08-30 2018-12-18 合肥工业大学 A kind of crystalline state tungstic acid/titanium doped amorphous state tungsten oxide nanometer linear array and preparation method thereof
CN110357626A (en) * 2019-07-26 2019-10-22 中国建筑材料科学研究总院有限公司 Doped tungsten oxide target and preparation method thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
P.K.SHEN,ET AL.: "The Performance of Electrochromic Tungsten Trioxide Films Doped with Cobalt or Nickel", 《JOURNAL OF THE ELECTROCHEMICAL SOCIETY》 *

Also Published As

Publication number Publication date
CN112501566B (en) 2023-03-14

Similar Documents

Publication Publication Date Title
JP5661278B2 (en) Method for producing refractory metal molded body
US20130206590A1 (en) Manufacture of High Density Indium Tin Oxide (ITO) Sputtering Target
CN110436915B (en) Zinc oxide doped target material for FBAR piezoelectric layer and preparation method thereof
US8778234B2 (en) Process for the manufacture of a high density ITO sputtering target
CN112624739A (en) Nickel oxide-based ceramic target material, thin film and thin film preparation process
US20110284364A1 (en) Aluminum Doped Zinc Oxide Sputtering Targets
CN108516820B (en) A kind of short route sintering process of tin indium oxide target material
CN112321280A (en) Gel injection molding preparation method of nickel oxide-based ceramic target material
CN102206804A (en) Sputtering target and preparation method thereof
WO2014021334A1 (en) Sintered oxide body and sputtering target
CN112723863A (en) Manufacturing method of advanced-generation TFT-grade fine-grain ITO target
NL2030121B1 (en) Method for preparing large-size high-quality potassium tantalum niobate ceramic target material
CN110002853A (en) The method that twice sintering process prepares IGZO ceramic target
WO2014125122A1 (en) Zno-al2o3-mgo sputtering target and method for the production thereof
CN111269013B (en) Yttria-based ultrahigh-temperature insulating ceramic special-shaped part and preparation method thereof
CN113990658B (en) High-remanence-ratio low-porosity hexagonal ferrite thick film and preparation method and application thereof
CN112479707A (en) Cold isostatic pressing preparation method of tungsten oxide-based ceramic target material
CN112374554A (en) High-purity high-activity nickel oxide-based powder, preparation method and application
JP2023512126A (en) Manufacturing method of vanadium tungsten alloy target material
CN112501566B (en) Tungsten oxide-based ceramic target material, thin film and thin film preparation process
CN112374542B (en) Submicron-grade doped tungsten oxide-based powder and preparation method and application thereof
CN114127029A (en) Oxide sputtering target
CN112481592A (en) Hot press molding preparation method of nickel oxide-based ceramic target material
CN116813331A (en) Strontium titanate ceramic and preparation method and application thereof
CN112358294A (en) Hot-pressing sintering preparation method of tungsten oxide-based ceramic target material

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant