Method for improving oxygen vacancies of target material by ultrasonic assistance, indium zinc oxide target material

Abstract

The application belongs to the technical field of semiconductors, and discloses a method for improving oxygen vacancies of a target material through ultrasonic assistance, which comprises the following steps: step 1: placing an indium zinc oxide target material precursor in a vacuum environment and a reducing atmosphere to sinter at a first temperature to obtain a semi-finished product; step 2: ultrasonic cleaning the semi-finished product obtained in step 1; and step 3: drying the semi-finished product obtained in step 2 after ultrasonic cleaning, and then sintering in a vacuum environment and a reducing atmosphere at a second temperature to obtain a finished product; the first temperature is lower than the second temperature; and the first temperature is at least 400 DEG C higher than the fat removal temperature. The method can make the atomic structure of the target material surface change through one sintering in a reducing atmosphere and then ultrasonic treatment, so that oxygen atoms are relatively easy to be removed during the second sintering, and then a satisfactory oxygen vacancy degree can be obtained during the second sintering. Meanwhile, the application also provides an indium zinc oxide target material.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor technology, and in particular to a method for improving oxygen vacancies of a target material by over-sonic assistance, and an indium zinc oxide target. BACKGROUND

[0002] The related prior art for improving oxygen vacancies of an indium zinc oxide target is as follows:

[0003] Prior art 1: CN116406223A discloses a method of manufacturing a semiconductor device includes: forming a stack structure by alternately stacking a gate layer and an interlayer insulating layer on a substrate; and forming a trench structure passing through the stack structure in a vertical direction, wherein forming the trench structure includes: forming an opening by etching the stack structure; forming a gate insulating layer covering a side surface of the opening; forming a variable resistance material layer on the gate insulating layer; changing an oxygen vacancy concentration in a region of the variable resistance material layer by performing a plasma treatment process or an annealing process on the variable resistance material layer; forming a core insulating pattern covering the variable resistance material layer and filling at least a portion of the opening; and forming a pad pattern on the core insulating pattern.

[0004] This scheme is to change the oxygen vacancy concentration in the region of the variable resistance material layer by performing a plasma treatment process or an annealing process on the variable resistance material layer.

[0005] Prior art 2: The prior application CN116216770A of the present applicant discloses a preparation method of a blue IZO powder, comprising the following steps: step 1: mixing indium oxide, zinc oxide, tin dioxide, a dispersing agent, and pure water to obtain slurry one; step 2: spray granulating the slurry one prepared in step 1 to obtain a yellow IZO precursor powder; step 3: adding a reducing agent to the yellow IZO precursor powder prepared in step 2, shearing by an emulsifying shear machine, and then adding to a high-pressure kettle, and after heat treatment and solid-liquid separation, a blue precipitate is obtained; step 4: washing, drying, and obtaining a blue IZO powder from the blue precipitate prepared in step 3. The blue IZO powder prepared by this method has a high oxygen vacancy concentration, thereby improving the carrier concentration and the conductivity.

[0006] This scheme is to add a reducing agent to the material, and the reducing agent is one or more of aniline, oxalic acid, ethanol, and ethylene glycol. This scheme is suitable for low-temperature sintering materials, and does not require high-temperature sintering, and there is no problem of rapid volatilization of the reducing agent.

[0007] Prior art 3: The prior application of the applicant CN115974530A discloses a low resistivity high mobility oxide target material and a preparation method thereof, the method is: the target blank is sequentially subjected to sintering under oxygen atmosphere and sintering under oxygen-free atmosphere, and the target blank is obtained; the metal oxide in the target blank is composed of praseodymium oxide, indium oxide, gallium oxide and zinc oxide. The present application provides a preparation method of a low resistivity high mobility oxide target material, which adopts the mode of sequentially sintering under oxygen atmosphere and sintering under oxygen-free atmosphere to heat sinter the target blank, and the combination of oxygen sintering and oxygen-free sintering produces a synergistic effect, which discharges all the dispersants and binders in the oxide target material, so that the oxide target material has a very high density and a high carrier mobility, and at the same time, the oxide target material produces oxygen vacancies, thereby reducing the resistivity of the oxide target material to obtain excellent conductivity.

[0008] Although this scheme records that the oxygen vacancy can be improved, there is no clear data to prove that the oxygen vacancy concentration can be further improved. Through experimental verification, the oxygen vacancy concentration can be further improved.

[0009] Based on the previous series of researches of the applicant, the present case is proposed.

[0010] Therefore, the technical problem solved by the present case is: how to improve the oxygen vacancy of the indium zinc oxide target material. SUMMARY

[0011] One of the purposes of the present application is to provide a method for improving the oxygen vacancy of a target material by ultrasonic assistance, which method is to perform a first sintering in a reducing atmosphere, then perform ultrasonic treatment to make the atomic structure of the target material surface change to a certain extent, and then the oxygen atoms will become relatively easy to be discharged during the second sintering, and then a satisfactory degree of oxygen vacancy can be obtained during the second sintering.

[0012] Meanwhile, the present application also provides an indium zinc oxide target material.

[0013] Unless otherwise specified in the present application, M is mol / L, and % is mass percentage.

[0014] To achieve the above-mentioned purpose, the present application provides a method for improving the oxygen vacancy of a target material by ultrasonic assistance, comprising the following steps:

[0015] Step 1: sinter the indium zinc oxide target material precursor in a vacuum environment and a reducing atmosphere at a first temperature to obtain a semi-finished product;

[0016] Step 2: ultrasonic cleaning of the semi-finished product obtained in step 1;

[0017] Step 3: dry the ultrasonic cleaned semi-finished product obtained in step 2 and sinter it in a vacuum environment and a reducing atmosphere at a second temperature to obtain a finished product;

[0018] The first temperature is lower than the second temperature; the first temperature is at least 400℃ higher than the degreasing temperature.

[0019] The degreasing temperature resin of the present application is decomposed by heating to 500-600℃ to decompose the organic components in the precursor. It also means that the first temperature is at least 900℃ or more. Through experimental research, it can be found that the first temperature of 900℃ combined with ultrasonic operation can improve the oxygen vacancy concentration, but if the first temperature is further increased to 1000℃, the improvement is more obvious.

[0020] The first temperature of the present application is relatively important. At the first temperature, the crystal structure of the surface of the semi-finished product has been preliminarily reconstructed. In the sintering process, the target material is basically densified from the outside first. At the first temperature, the target material as a whole has become relatively dense, but the surface layer is more dense. Therefore, at this time, the ultrasonic target material will not be mixed with water, and at the same time, it can wash away the dirt and impurities attached to the surface during sintering and affect the structure of the target material surface that is not completely dense, so that it can provide a smooth path for the oxygen release during subsequent sintering.

[0021] Through ultrasonic treatment, the atomic structure of the target material surface is changed, and the oxygen atom release will become relatively easy during the second sintering, and a more satisfactory oxygen vacancy degree can be obtained during the second sintering.

[0022] The vacuum environment of the present application is not and absolutely cannot reach absolute vacuum. The vacuum environment of the present application refers to the lowest vacuum degree that can be allowed in industry; for example, the vacuum degree is 0.01Pa-0.006Pa.

[0023] As an alternative means, a small amount of inert gas can be filled, so that the vacuum degree does not have to be very low.

[0024] In the above method for improving the oxygen vacancy of the target material by ultrasonic assistance, the first temperature is 1000-1200℃, and the sintering time of step 1 is 8-12h.

[0025] As some optional schemes of the embodiments of the present application, the first temperature can be 1000℃, 1050℃, 1100℃, 1150℃ or 1200℃; the sintering time can be 8h, 9h, 10h, 11h or 12h;

[0026] In the above method for improving the oxygen vacancy of the target material by ultrasonic assistance, the second temperature is 1350-1450℃, and the sintering time of step 3 is 6-8h.

[0027] As some optional schemes of the embodiment of the present application, the second temperature can be 1350℃, 1380℃, 1400℃, 1420℃ or 1450℃; the sintering time can be 6h, 6.5h, 70h, 7.5h or 8h.

[0028] In the method for improving oxygen vacancies of target material by ultrasonic assistance, the temperature increasing speed from normal temperature to the second temperature in step 3 is 1-4℃ / min.

[0029] In the method for improving oxygen vacancies of target material by ultrasonic assistance, the ultrasonic parameters in step 2 are as follows: the frequency is 90-180KHz, and the time is 1-2h.

[0030] As some optional schemes of the embodiment of the present application, the frequency is 90KHz, 100KHz, 110KHz, 120KHz, 130KHz, 140KHz, 150KHz, 160KHz, 170KHz or 180KHz; the lower the frequency is, the time can be appropriately prolonged.

[0031] In the method for improving oxygen vacancies of target material by ultrasonic assistance, the solvent used in the ultrasonic cleaning in step 2 is pure water or a mixture of pure water and isopropyl alcohol; the weight ratio of pure water to isopropyl alcohol is 9-10:1-0.

[0032] In the method for improving oxygen vacancies of target material by ultrasonic assistance, the mass ratio of indium oxide to zinc oxide in the indium zinc oxide target precursor is 77.5-93.2:6.8-22.5.

[0033] In the method for improving oxygen vacancies of target material by ultrasonic assistance, the reducing atmosphere in step 1 is specifically as follows:

[0034] The indium zinc oxide target precursor and the titanium powder are placed in the same sintering atmosphere in a non-contact manner.

[0035] And / or, the semi-finished product and the titanium powder are placed in the same sintering atmosphere in a non-contact manner in step 3.

[0036] In the method for improving oxygen vacancies of target material by ultrasonic assistance, the weight of the titanium powder is 0.1%-100% of the weight of the finished product, preferably, the weight of the titanium powder is 1%-80% of the weight of the finished product; preferably, the weight of the titanium powder is 5%-80% of the weight of the finished product.

[0037] Finally, the present application also discloses an indium zinc oxide target prepared by any of the above methods.

[0038] Compared with the prior art, the present application has the following advantages:

[0039] 1. The vacuum atmosphere formed by the vacuum and titanium powder in the sintering method of the present invention can generate more oxygen vacancies on the surface of the target material, thereby improving the mobility.

[0040] 2. In the present invention, by subjecting the sintered target material to ultrasonic treatment and then sintering it again, the atomic structure on the surface of the target material can be changed to a certain extent, and it becomes relatively easy for oxygen atoms to escape during sintering again.

[0041] The oxygen vacancy concentration can be significantly increased by adding ultrasonic operation between the primary and secondary firings. DETAILED DESCRIPTION

[0042] The present invention will be further described below in conjunction with the embodiments, but this does not constitute any limitation to the present invention. Any limited modifications made within the scope of the claims of the present invention are still within the scope of the claims of the present invention.

[0043] In order to explain the technical content of the present invention in detail, further description will be given below in conjunction with the embodiments.

[0044] Example 1

[0045] Preparation of indium zinc oxide target

[0046] (1) Weigh indium oxide and zinc oxide powder in a mass ratio of 77.5:22.5 and set aside.

[0047] (2) Add a certain amount of pure water to the slurry barrel, and add the zinc oxide powder and PVP weighed in step 1 into the slurry barrel in sequence for pre-dispersion. The dispersion time is 30 minutes and the dispersion speed is 100 rpm. The PVP accounts for 4% of the total mass of the added zinc oxide powder, pure water and PVP.

[0048] (3) The slurry obtained in step 2 was pumped into a sand mill using a pneumatic diaphragm pump for grinding. The grinding time was 12 h and the grinding speed was 1500 r / min to obtain slurry 1.

[0049] (4) Indium oxide powder and PVP were added to the slurry 1 obtained in step 3 and dispersed for 30 minutes at a dispersion speed of 100 rpm. The resulting slurry was then pumped into a sand mill using a pneumatic diaphragm pump and ground for 8 hours at a grinding speed of 1500 rpm to obtain slurry 2. The PVP accounted for 4% of the total weight of the added indium oxide powder and PVP.

[0050] (5) PVA was added to the slurry 2 obtained in step 4 and pre-dispersed for 30 minutes at a dispersion speed of 100 rpm. The slurry was then pumped into a sand mill using a pneumatic diaphragm pump and ground for 2 hours at a grinding speed of 1500 rpm to obtain slurry 3. The binder accounted for 10% of the total weight of the added indium oxide powder, zinc oxide, and binder.

[0051] (6) The slurry obtained in step 5 is fed into a spray drying tower for spray granulation, followed by mixing and sieving to obtain an indium aluminum oxide mixed powder. The air outlet temperature is 75° C., and the atomizer frequency is 120 Hz.

[0052] (7) The mixed powder obtained in step 6 is molded by molding and cold isostatic pressing to obtain an indium zinc oxide target embryo.

[0053] (8) A layer of alumina fine sand with a thickness of about 1.5-2.5 mm is evenly spread on the sintering furnace support plate. The purity of the alumina fine sand is not less than 98%, and the particle size is between 0.15-0.25 mm.

[0054] (9) Place the target obtained in step 7 on the prepared alumina fine sand, cover it with a support plate, and place a quartz boat filled with elemental titanium powder on the support plate, wherein the amount of elemental titanium powder is 80% of the weight of the target material. Metallic elemental titanium absorbs oxygen in the crystal lattice under vacuum conditions to generate more oxygen vacancies, thereby increasing its carrier concentration and conductivity.

[0055] (10) The furnace door is closed for vacuum sintering at a heating rate of 1°C / min. The temperature is raised to 500°C and kept at this temperature for 8 hours. The temperature is then raised to 1100°C and kept at this temperature for 8 hours. The temperature is then lowered to room temperature to obtain the target material.

[0056] (11) The removed target material was placed in an ultrasonic machine for ultrasonic treatment. The ultrasonic solution medium was pure water, the ultrasonic power was 160 kHz, and the time was 1 hour. The ultrasonically treated target material was then placed back into a sintering furnace at a heating rate of 4°C / min. The temperature was raised to 1400°C, maintained at that temperature for 8 hours, and then cooled to obtain the target material.

[0057] (12) The relative density of the target obtained in step 11 was measured to be 99.14%, and the oxygen vacancy concentration was 5.78E+19cm -3 .

[0058] (13) The obtained target material was sputtered using a sputtering coating machine with Ar / O2 / H2 as the working gas, a sputtering power of 100W, a pressure of 0.4Pa, a substrate temperature of 200°C, a gas flow rate of 1% O2 / 1.8% H2, a pre-sputtering time of 300s, and a sputtering time of 380s. The measured mobility of the glass sheet was 26.49cm 2(V·S)

[0059] Example 2

[0060] (1) Take indium oxide and zinc oxide powder in a mass ratio of 80:20 for use.

[0061] (2) Add a certain amount of pure water to the slurry barrel, and then add the zinc oxide powder and PVP in step (1) to the slurry barrel for pre-dispersion. The dispersion time is 30 min, and the dispersion speed is 100 rpm. The PVP accounts for 4% of the total mass of the added zinc oxide powder, pure water and PVP.

[0062] (3) The slurry obtained in step 2 is pumped into a sand mill for grinding by a pneumatic diaphragm pump. The grinding time is 12 h, and the grinding speed is 1500 r / min. Slurry one is obtained.

[0063] (4) Add indium oxide powder and PVP to the slurry one obtained in step 3 for dispersion. The dispersion time is 30 min, and the dispersion speed is 100 rpm. Then the obtained slurry is pumped into a sand mill for grinding by a pneumatic diaphragm pump. The grinding time is 8 h, and the grinding speed is 1500 rpm. Slurry two is obtained. The PVP accounts for 4% of the total mass of the added indium oxide powder and PVP.

[0064] (5) Add PVA to the slurry two obtained in step 4 for pre-dispersion. The pre-dispersion time is 30 min, and the dispersion speed is 100 rpm. Then the slurry is pumped into a sand mill for grinding by a pneumatic diaphragm pump. The grinding time is 2 h, and the grinding speed is 1500 rpm. Slurry three is obtained. The binder accounts for 10% of the total mass of the added indium oxide powder, zinc oxide and binder.

[0065] (6) The slurry three obtained in step 5 is pumped into a spray drying tower for spray granulation, then mixed and sieved to obtain an indium aluminum oxide mixed powder. The outlet air temperature is 75°C, and the atomizer frequency is 120 Hz.

[0066] (7) The mixed powder obtained in step 6 is molded by die pressing and cold isostatic pressing to obtain an indium zinc oxide target blank.

[0067] (8) A layer of alumina fine sand with a thickness of about 1.5-2.5 mm is evenly laid on the sintering furnace supporting plate. The purity of the alumina fine sand is not less than 98%, and the particle size is between 0.15-0.25 mm.

[0068] (9) Put the target obtained in step 7 on the prepared alumina fine sand, cover it with a fireproof plate, and place a quartz boat containing titanium powder on the fireproof plate, wherein the amount of the titanium powder is 80% of the weight of the target material. The metallic titanium absorbs oxygen in the crystal lattice under vacuum conditions to generate more oxygen vacancies, thereby increasing the carrier concentration and conductivity.

[0069] (10) Close the furnace door and perform vacuum sintering at a heating rate of 1°C / min, heat to 500°C and keep for 8h, then continue to heat to 1100°C and keep for 8h, then cool down to room temperature to obtain the target material.

[0070] (11) Put the target material taken out into an ultrasonic machine for ultrasonic treatment, the ultrasonic solution medium is pure water, the ultrasonic power is 160KHz, and the time is 1h. Then put the ultrasonic treated target material into the sintering furnace again, heat at a rate of 4°C / min, heat to 1400°C and keep for 8h, then cool down to obtain the target material.

[0071] (12) The relative density of the target material obtained in step 11 is 99.17%, and the oxygen vacancy concentration is 4.98E+19cm -3 .

[0072] (13) The obtained target material is used in a sputtering coating machine, Ar / O2 / H2 is used as working gas for sputtering, the sputtering power is 100w, the pressure is 0.4Pa, the substrate temperature is 200°C, the gas flow is 1%O2 / 1.8%H2, the pre-sputtering time is 300s, and the sputtering time is 380s. The measured glass sheet mobility is 25.87cm 2 / (V·S).

[0073] Example 3

[0074] Generally the same as example 1, except that step 1 is: take indium oxide and zinc oxide powder according to a mass ratio of 90:10 for standby.

[0075] The relative density of the target material is 98.86%, and the oxygen vacancy concentration is 4.59E+19cm -3 .

[0076] The obtained target material is used in a sputtering coating machine, Ar / O2 / H2 is used as working gas for sputtering, the sputtering power is 100w, the pressure is 0.4Pa, the substrate temperature is 200°C, the gas flow is 1%O2 / 1.8%H2, the pre-sputtering time is 300s, and the sputtering time is 380s. The measured glass sheet mobility is 25.61cm 2 / (V·S).

[0077] Example 4

[0078] The embodiment 1 is substantially the same except that the ultrasonic power is 90 KHz and the time is 2 h.

[0079] The relative density of the target material is 99.06%, and the oxygen vacancy concentration is 4.15E+19 cm -3 .

[0080] The obtained target material is sputtered by using a sputtering coating machine, Ar / O2 / H2 as working gas, sputtering power 100 w, pressure 0.4 Pa, substrate temperature 200 ℃, gas flow 1% O2 / 1.8% H2, pre-sputtering time 300 s, and sputtering time 380 s. The mobility of the glass sheet is measured to be 23.51 cm 2 / (V·S).

[0081] Embodiment 5

[0082] The embodiment 1 is substantially the same except that step 10 is: closing the furnace door for vacuum sintering, the heating rate is 1 ℃ / min, the temperature is raised to 500 ℃ and kept for 8 h, then the temperature is continuously raised to 1150 ℃ and kept for 8 h, then the temperature is lowered to obtain the target material.

[0083] Step 11 is: the target material taken out is put into an ultrasonic machine for ultrasonic treatment, the ultrasonic power is 90 KHz, and the time is 2 h. Then the target material after ultrasonic treatment is put into the sintering furnace again, the heating rate is 2 ℃ / min, the temperature is raised to 1350 ℃ and kept for 8 h, then the temperature is lowered to obtain the target material.

[0084] The relative density of the target material is 98.28%, and the oxygen vacancy concentration is 3.79E+19 cm -3 .

[0085] The obtained target material is sputtered by using a sputtering coating machine, Ar / O2 / H2 as working gas, sputtering power 100 w, pressure 0.4 Pa, substrate temperature 200 ℃, gas flow 1% O2 / 1.8% H2, pre-sputtering time 300 s, and sputtering time 380 s. The mobility of the glass sheet is measured to be 23.51 cm 2 / (V·S).

[0086] Embodiment 6

[0087] The embodiment 1 is substantially the same except that step 10 is: closing the furnace door for vacuum sintering, the heating rate is 1 ℃ / min, the temperature is raised to 500 ℃ and kept for 8 h, then the temperature is continuously raised to 1150 ℃ and kept for 8 h, then the temperature is lowered to obtain the target material.

[0088] Step 11: The target material taken out is placed into an ultrasonic machine for ultrasonic treatment, with an ultrasonic power of 180 KHz and a time of 1 h. Then the target material after ultrasonic treatment is placed into a sintering furnace again, with a heating rate of 3 ℃ / min, heated to 1450 ℃ and kept for 7 h, and then cooled to obtain the target material.

[0089] The relative density of the target material is 99.09%, and the oxygen vacancy concentration is 4.93E+19 cm -3 .

[0090] The target material obtained is used in a sputtering coating machine, with Ar / O2 / H2 as working gas for sputtering, a sputtering power of 100 w, a pressure of 0.4 Pa, a substrate temperature of 200 ℃, a gas flow of 1% O2 / 1.8% H2, a pre-sputtering time of 300 s, and a sputtering time of 380 s. The mobility of the glass sheet is measured to be 22.59 cm 2 / (V·S).

[0091] Comparative Example 1

[0092] (1) Indium oxide and zinc oxide powders are weighed according to a mass ratio of 77.5:22.5 for standby.

[0093] (2) A certain amount of pure water is added to the slurry barrel, and the zinc oxide powder and PVP weighed in step (1) are sequentially added to the slurry barrel for pre-dispersion, with a dispersion time of 30 min and a dispersion speed of 100 rpm. The PVP accounts for 4% of the total mass of the added zinc oxide powder, pure water, and PVP.

[0094] (3) The slurry obtained in step 2 is pumped into a sand mill with a pneumatic diaphragm pump for grinding. The grinding time is 12 h, and the grinding speed is 1500 r / min. Slurry one is obtained.

[0095] (4) Indium oxide powder and PVP are added to the slurry one obtained in step 3 for dispersion, with a dispersion time of 30 min and a dispersion speed of 100 rpm. Then the obtained slurry is pumped into a sand mill with a pneumatic diaphragm pump for grinding, with a grinding time of 8 h and a grinding speed of 1500 rpm. Slurry two is obtained. The PVP accounts for 4% of the total mass of the added indium oxide powder and PVP.

[0096] (5) PVA is added to the slurry two obtained in step 4 for pre-dispersion, with a pre-dispersion time of 30 min and a dispersion speed of 100 rpm. Then the slurry is pumped into a sand mill with a pneumatic diaphragm pump for grinding, with a grinding time of 2 h and a grinding speed of 1500 rpm. Slurry three is obtained. The binder accounts for 10% of the total mass of the added indium oxide powder, zinc oxide, and binder.

[0097] (6) The slurry obtained in step 5 is fed into a spray drying tower for spray granulation, followed by mixing and sieving to obtain an indium aluminum oxide mixed powder. The air outlet temperature is 75° C., and the atomizer frequency is 120 Hz.

[0098] (7) The mixed powder obtained in step 6 is molded by molding and cold isostatic pressing to obtain an indium zinc oxide target embryo.

[0099] (8) A layer of alumina fine sand with a thickness of about 1.5-2.5 mm is evenly spread on the sintering furnace support plate. The purity of the alumina fine sand is not less than 98%, and the particle size is between 0.15-0.25 mm.

[0100] (9) Place the target obtained in step 7 on the prepared alumina fine sand, cover it with a support plate, and place a quartz boat filled with elemental titanium powder on the support plate, wherein the amount of elemental titanium powder is 80% of the weight of the target material. Metallic elemental titanium absorbs oxygen in the crystal lattice under vacuum conditions to generate more oxygen vacancies, thereby increasing its carrier concentration and conductivity.

[0101] (10) Close the furnace door and perform vacuum sintering at a heating rate of 1°C / min. Heat to 500°C and keep warm for 8 hours, then continue to heat to 1100°C and keep warm for 8 hours, then continue to heat to 1400°C and keep warm for 8 hours, then cool down to room temperature to obtain the target material.

[0102] (11) The relative density of the target obtained in step 11 was measured to be 97.85%, and the oxygen vacancy concentration was 1.98E+17cm -3 .

[0103] (12) The obtained target material was sputtered using a sputtering coating machine with Ar / O2 / H2 as the working gas, a sputtering power of 100W, a pressure of 0.4Pa, a substrate temperature of 200°C, a gas flow rate of 1% O2 / 1.8% H2, a pre-sputtering time of 300s, and a sputtering time of 380s. The measured glass sheet mobility was 19.87cm 2 / (V·S).

[0104] Comparative Example 2

[0105] (1) Weigh indium oxide and zinc oxide powder in a mass ratio of 77.5:22.5 and set aside.

[0106] (2) Add a certain amount of pure water to the slurry barrel, and add the zinc oxide powder and PVP weighed in step (1) into the slurry barrel in sequence for pre-dispersion. The dispersion time is 30 minutes and the dispersion speed is 100 rpm. The PVP accounts for 4% of the total mass of the added zinc oxide powder, pure water and PVP.

[0107] (3) The slurry obtained in step 2 is pumped into a sand mill by a pneumatic diaphragm pump for grinding. The grinding time is 12 h, and the grinding speed is 1500 r / min. The slurry one is obtained.

[0108] (4) The slurry one obtained in step 3 is added with indium oxide powder and PVP for dispersion. The dispersion time is 30 min, and the dispersion speed is 100 rpm. Then the obtained slurry is pumped into a sand mill by a pneumatic diaphragm pump for grinding. The grinding time is 8 h, and the grinding speed is 1500 rpm. The slurry two is obtained. The PVP accounts for 4% of the total mass of the added indium oxide powder and PVP.

[0109] (5) The slurry two obtained in step 4 is added with PVA for pre-dispersion. The pre-dispersion time is 30 min, and the dispersion speed is 100 rpm. Then the slurry is pumped into a sand mill by a pneumatic diaphragm pump for grinding. The grinding time is 2 h, and the grinding speed is 1500 rpm. The slurry three is obtained. The binder accounts for 10% of the total mass of the added indium oxide powder, zinc oxide and binder.

[0110] (6) The slurry three obtained in step 5 is pumped into a spray drying tower for spray granulation, and then is mixed and sieved to obtain the indium aluminum oxide mixed powder. The air outlet temperature is 75℃, and the atomizer frequency is 120 Hz.

[0111] (7) The mixed powder obtained in step 6 is molded by die pressing and cold isostatic pressing to obtain the indium zinc oxide target blank.

[0112] (8) A layer of alumina fine sand with a thickness of about 1.5-2.5 mm is uniformly laid on the supporting plate of the sintering furnace. The purity of the alumina fine sand is not less than 98%, and the particle size is between 0.15-0.25 mm.

[0113] (9) The target blank obtained in step 7 is placed on the laid alumina fine sand, and a layer of supporting plate is covered. The furnace door is closed for vacuum sintering. The heating rate is 1℃ / min, the temperature is raised to 500℃ and kept for 8 h, then the temperature is continuously raised to 750℃ and kept for 8 h, and then the temperature is lowered to room temperature to obtain the target material.

[0114] (10) The target material taken out is placed in an ultrasonic machine for ultrasonic treatment. The ultrasonic power is 160 KHz. After a period of ultrasonic treatment, the target material is disintegrated, and the experiment is completed.

[0115] Comparative Example 3

[0116] Comparative Example 2 was substantially the same as Comparative Example 1, except that in step 9, the target embryo obtained in step 7 was placed on the prepared alumina fine sand and covered with a layer of fireproof plate. The furnace door was closed for vacuum sintering, the heating rate was 1°C / min, the temperature was raised to 500°C and held for 8h, then the temperature was continuously raised to 1280°C and held for 8h, then the temperature was lowered to room temperature to obtain the target material.

[0117] The target material taken out was placed in an ultrasonic machine for ultrasonic treatment, the ultrasonic power was 160KHz, and the time was 1h. Then the ultrasonic treated target material was again placed in a sintering furnace, the heating rate was 4 / min, the temperature was raised to 1400°C and held for 8h, then the temperature was lowered to obtain the target material.

[0118] The relative density of the target material was 95.23%, the oxygen vacancy concentration was 2.95E+12cm -3 .

[0119] The obtained target material was used in a sputtering coating machine, Ar / O2 / H2 was used as the working gas for sputtering, the sputtering power was 100w, the pressure was 0.4Pa, the substrate temperature was 200°C, the gas flow was 1%O2 / 1.8%H2, the pre-sputtering time was 300s, and the sputtering time was 380s. The measured glass sheet mobility was 12.36cm 2 / (V·S).

[0120] Comparative Example 4

[0121] (1) Indium oxide and zinc oxide powders were weighed according to a mass ratio of 77.5:22.5 for standby use.

[0122] (2) A certain amount of pure water was added to the slurry barrel, and the zinc oxide powder and PVP weighed in step (1) were sequentially added to the slurry barrel for pre-dispersion, the dispersion time was 30min, and the dispersion rotation speed was 100rpm, wherein the PVP accounted for 4% of the total mass of the added zinc oxide powder, pure water and PVP.

[0123] (3) The slurry obtained in step 2 was pumped into a sand mill with a pneumatic diaphragm pump for grinding. The grinding time was 12h, the grinding rotation speed was 1500r / min, and slurry one was obtained.

[0124] (4) Indium oxide powder and PVP were added to the slurry one obtained in step 3 for dispersion, the dispersion time was 30min, and the dispersion rotation speed was 100rpm. Then the obtained slurry was pumped into a sand mill with a pneumatic diaphragm pump for grinding, the grinding time was 8h, and the grinding rotation speed was 1500rpm to obtain slurry two. The PVP accounted for 4% of the total mass of the added indium oxide powder and PVP.

[0125] (5) After adding PVA to the slurry two obtained in step 4, pre-dispersing is performed for 30 min at a dispersing rotation speed of 100 rpm, and then the slurry is pumped into a sand mill by a pneumatic diaphragm pump for grinding for 2 h at a grinding rotation speed of 1500 rpm to obtain slurry three. The binder accounts for 10% of the total mass of the indium oxide powder, zinc oxide and binder added.

[0126] (6) The slurry three obtained in step 5 is pumped into a spray drying tower for spray granulation, and then mixing and screening are performed to obtain an indium aluminum oxide mixed powder. The air outlet temperature is 75°C, and the atomizer frequency is 120 Hz.

[0127] (7) The mixed powder obtained in step 6 is formed by die pressing and cold isostatic pressing to obtain an indium zinc oxide target blank.

[0128] (8) The target blank obtained in step 7 is placed in a sintering furnace, the furnace door is closed for vacuum sintering, the heating rate is 1°C / min, the temperature is raised to 500°C for 8 h, then the temperature is continuously raised to 1100°C for 8 h, then the temperature is continuously raised to 1400°C for 8 h, and then the temperature is lowered to room temperature to obtain the target material.

[0129] (9) The relative density of the target material obtained in step 8 is 96.07%, and the oxygen vacancy concentration is 4.91E+12 cm-3.

[0130] (10) The target material obtained is used in a sputtering coating machine, Ar / O2 / H2 is used as the working gas for sputtering, the sputtering power is 100 w, the pressure is 0.4 Pa, the substrate temperature is 200°C, the gas flow is 1% O2 / 1.8% H2, the pre-sputtering time is 300 s, and the sputtering time is 380 s. The measured glass sheet mobility is 13.84 cm2 / (V·S).

[0131] In order to further verify the effect of ultrasonic on other target materials, an indium tin oxide target material is used as the research object for analysis. The specific case is as follows:

[0132] Comparative Example 5

[0133] (1) Indium oxide and tin oxide powder are weighed according to a molar ratio of 97:3 for standby use.

[0134] (2) A certain amount of pure water is added to the slurry barrel, and the tin oxide powder and PVP weighed in step 1 are sequentially added to the slurry barrel for pre-dispersing, the dispersing time is 30 min, the dispersing rotation speed is 100 rpm, and the PVP accounts for 4% of the total mass of the tin oxide powder, pure water and PVP added.

[0135] (3) The slurry obtained in step 2 is pumped into a sand mill by a pneumatic diaphragm pump for grinding. The grinding time is 12 h, and the grinding speed is 1500 r / min. The slurry one is obtained.

[0136] (4) The slurry one obtained in step 3 is added with indium oxide powder and PVP for dispersion. The dispersion time is 30 min, and the dispersion speed is 100 rpm. Then the obtained slurry is pumped into a sand mill by a pneumatic diaphragm pump for grinding. The grinding time is 8 h, and the grinding speed is 1500 rpm. The slurry two is obtained. The PVP accounts for 4% of the total mass of the added indium oxide powder and PVP.

[0137] (5) The slurry two obtained in step 4 is added with PVA for pre-dispersion. The pre-dispersion time is 30 min, and the dispersion speed is 100 rpm. Then the slurry is pumped into a sand mill by a pneumatic diaphragm pump for grinding. The grinding time is 2 h, and the grinding speed is 1500 rpm. The slurry three is obtained. The binder accounts for 10% of the total mass of the added indium oxide powder, tin oxide and binder.

[0138] (6) The slurry three obtained in step 5 is pumped into a spray drying tower for spray granulation, and then is mixed and sieved to obtain the indium tin oxide mixed powder. The air outlet temperature is 75℃, and the atomizer frequency is 120 Hz.

[0139] (7) The mixed powder obtained in step 6 is formed by die pressing and cold isostatic pressing to obtain the indium tin oxide target blank

[0140] (8) A layer of alumina fine sand with a thickness of about 1.5-2.5 mm is uniformly laid on the supporting plate of the sintering furnace. The purity of the alumina fine sand is not less than 98%, and the particle size is between 0.15-0.25 mm.

[0141] (9) The target blank obtained in step 7 is placed on the laid alumina fine sand, and a layer of supporting plate is covered, and a quartz boat filled with titanium powder is placed on the supporting plate. The amount of titanium powder is 80% of the weight of the target material. For example, elemental titanium is used to absorb oxygen in the lattice under vacuum conditions to generate more oxygen vacancies, thereby improving the carrier concentration and conductivity.

[0142] (10) The furnace door is closed for vacuum sintering. The heating rate is 1℃ / min. The temperature is raised to 500℃ and kept for 8 h. Then the temperature is continuously raised to 1100℃ and kept for 8 h. Then the temperature is continuously raised to 1400℃ and kept for 8 h. Then the temperature is lowered to room temperature to obtain the target material.

[0143] (11) The relative density of the target material obtained in step 11 is 99.47%, and the oxygen vacancy concentration is 1.96E+14 cm -3 .

[0144] (12) The obtained target material is sputtered using a sputtering coating machine, Ar / O2 / H2 as working gas, sputtering power 100 w, pressure 0.4 Pa, substrate temperature 200 DEG C, gas flow 1% O2 / 1.8% H2, pre-sputtering time 300 s, sputtering time 380 s. The mobility of the glass sheet is measured to be 14.23 cm2 / (V·S).

[0145] Comparative Example 6

[0146] (1) Indium oxide and tin oxide powder are weighed according to the ratio of 97:3.

[0147] (2) A certain amount of pure water is added to the slurry barrel, and the tin oxide powder and PVP weighed in step 1 are sequentially added to the slurry barrel for pre-dispersion, the dispersion time is 30 min, the dispersion speed is 100 rpm, and the PVP accounts for 4% of the total mass of the added tin oxide powder, pure water and PVP.

[0148] (3) The slurry obtained in step 2 is pumped into a sand mill by a pneumatic diaphragm pump for grinding. The grinding time is 12 h, the grinding speed is 1500 r / min, and the slurry one is obtained.

[0149] (4) Indium oxide powder and PVP are added to the slurry one obtained in step 3 for dispersion, the dispersion time is 30 min, the dispersion speed is 100 rpm. Then the obtained slurry is pumped into a sand mill by a pneumatic diaphragm pump for grinding, the grinding time is 8 h, the grinding speed is 1500 rpm, and the slurry two is obtained. The PVP accounts for 4% of the total mass of the added indium oxide powder and PVP.

[0150] (5) PVA is added to the slurry two obtained in step 4 for pre-dispersion, the pre-dispersion time is 30 min, the dispersion speed is 100 rpm, then the slurry is pumped into a sand mill by a pneumatic diaphragm pump for grinding, the grinding time is 2 h, the grinding speed is 1500 rpm, and the slurry three is obtained. The binder accounts for 10% of the total mass of the added indium oxide powder, tin oxide and binder.

[0151] (6) The slurry three obtained in step 5 is pumped into a spray drying tower for spray granulation, then mixing and screening are performed to obtain indium tin oxide mixed powder. The air outlet temperature is 75 DEG C, and the atomizer frequency is 120 Hz.

[0152] (7) The mixed powder obtained in step 6 is formed by molding and cold isostatic pressing to obtain an indium tin oxide target blank

[0153] A layer of alumina fine sand with a thickness of about 1.5-2.5 mm is evenly laid on the sintering furnace supporting plate, the purity of the alumina fine sand is not less than 98%, and the particle size is between 0.15-0.25 mm.

[0154] (9) Put the target in the prepared alumina sand, cover with a layer of supporting plate, and put a quartz boat filled with titanium powder on the supporting plate, wherein the amount of titanium powder is 80% of the weight of the target, for example, elemental titanium is used to absorb oxygen in the lattice under vacuum conditions to generate more oxygen vacancies, thereby increasing the carrier concentration and conductivity.

[0155] (10) Close the furnace door and perform vacuum sintering at a heating rate of 1°C / min, heat to 500°C and keep for 8h, then continue to heat to 1100°C and keep for 8h, then cool down to room temperature to obtain the target.

[0156] (11) Put the taken-out target into an ultrasonic machine for ultrasonic treatment at a power of 160KHz for 1h. Then put the ultrasonic treated target into the sintering furnace again at a heating rate of 4°C / min, heat to 1400°C and keep for 8h, then cool down to obtain the target.

[0157] (12) The relative density of the target obtained in step 11 is 99.51%, and the oxygen vacancy concentration is 1.88E+14cm -3 .

[0158] (13) The obtained target is used in a sputtering coating machine, Ar / O2 / H2 is used as working gas for sputtering, the sputtering power is 100w, the pressure is 0.4Pa, the substrate temperature is 200°C, the gas flow is 1%O2 / 1.8%H2, the pre-sputtering time is 300s, and the sputtering time is 380s. The measured glass sheet mobility is 14.36cm 2 / (V·S)

[0159] Result analysis

[0160] In summary, the characteristics of the present case are as follows:

[0161] 1. As can be seen from Example 1, Example 2 and Example 3, with the gradual increase of zinc oxide powder, the oxygen vacancy concentration gradually increases, indicating that the oxygen vacancy concentration and the zinc oxide powder are closely related, and the possible reason is that the surface density of indium zinc oxide gradually decreases with the increase of the amount of zinc, and ultrasonic treatment is beneficial to the rearrangement of surface atoms.

[0162] From this point of view, Comparative Examples 5 and 6 can further confirm that in Comparative Examples 5 and 6, indium oxide and tin oxide targets with larger surface density are used, and ultrasonic treatment has little effect on them.

[0163] Therefore, it can be seen that in a non-contact reducing atmosphere, ultrasonic treatment may have a significant effect on the target with a small surface density after sintering, and this effect may be further extended to other targets with similar properties.

[0164] 2. From Example 1, Example 4, Example 5, Example 6, it can be seen that the oxygen vacancy concentration and ultrasonic frequency and time, heating temperature, etc. have certain relevance, wherein the appropriate increase of ultrasonic frequency is more favorable for the increase of oxygen vacancy concentration.

[0165] 3. From Example 1, Comparative Example 1, it can be seen that in the absence of ultrasonic, in the reduction non-contact process, its improvement for oxygen vacancy concentration is limited; from Example 1 and Comparative Example 2, it can be seen that if the sintering temperature is not up to standard, it will collapse in water; from Example 1 and Comparative Example 3, it can be seen that in the absence of elemental titanium, there is almost no optimization for the oxygen vacancy concentration, and even there is a tendency to deteriorate (comparable to Comparative Example 4, since the gap is not large, it is not excluded that measurement error exists).

[0166] In the present application, the selection of titanium is the elemental substance repeatedly optimized by the project, and the oxide of titanium has the following characteristics: high temperature stability, not easy to gasify and sublimate; the elemental titanium has the following characteristics: not easy to soften at sintering temperature, good activity at sintering temperature, not easy to gasify and sublimate; the former ensures that it does not contaminate the target material, and the latter ensures that it can effectively absorb oxygen;

[0167] For example, iron will decompose above 1200°C; aluminum has an oxide film on its surface, which is difficult to react; alkali metals are too active and easy to volatilize; zinc element sublimates at about 1000°C, carbon powder is extremely easy to fly and easily contaminates the target material.

[0168] The examples presented herein are only selected from the combination of all possible examples. The appended claims should not be limited by the description of the embodiments of the present application. Some numerical ranges used in the claims include sub-ranges within them, and variations in these ranges should also be covered by the appended claims.

Claims

1. A method for increasing oxygen vacancies in a target material by ultrasound assistance, characterized in that: The steps include: Step 1: placing an indium zinc oxide target precursor in a vacuum environment and a reducing atmosphere and sintering it at a first temperature to obtain a semi-finished product; Step 2: ultrasonically clean the semi-finished product obtained in step 1; Step 3: drying the semi-finished product obtained in step 2 after ultrasonic cleaning, and then sintering it at a second temperature in a vacuum environment and a reducing atmosphere to obtain a finished product; The first temperature is lower than the second temperature; the first temperature is at least 400°C higher than the degreasing temperature; the reducing atmosphere in step 1 is specifically: placing the indium zinc oxide target precursor and titanium powder in the same sintering atmosphere in a non-contact manner; and / or, in step 3, placing the semi-finished product and titanium powder in the same sintering atmosphere in a non-contact manner.

2. The method for increasing target oxygen vacancies by ultrasound assistance according to claim 1, characterized in that: The first temperature is 1000-1200° C., and the sintering time in step 1 is 8-12 hours.

3. The method for increasing target oxygen vacancies by ultrasound assistance according to claim 1, characterized in that: The second temperature is 1350-1450° C., and the sintering time in step 3 is 6-8 hours.

4. The method for increasing target oxygen vacancies by ultrasound assistance according to claim 3, characterized in that: In step 3, the heating rate from room temperature to the second temperature is 1-4°C / min.

5. The method for increasing target oxygen vacancies by ultrasound assistance according to claim 1, characterized in that: The ultrasonic parameters of step 2 are: frequency of 90-180 KHz, and time of 1-2 hours.

6. The method for increasing target oxygen vacancies by ultrasound assistance according to claim 5, characterized in that: The solvent used for ultrasonic cleaning in step 2 is: pure water or a mixture of pure water and isopropyl tone; the weight ratio of pure water to isopropyl tone is 9-10:1-0.

7. The method for increasing target oxygen vacancies by ultrasound assistance according to claim 1, characterized in that: The mass ratio of indium oxide to zinc oxide in the indium zinc oxide target precursor is 77.5-93.2: 6.8-22.

5.

8. The method for increasing oxygen vacancies in a target material by ultrasound assistance according to claim 1, characterized in that: The weight of the titanium powder is equivalent to 0.1% to 100% of the weight of the finished product.

9. The method for increasing oxygen vacancies in a target material by ultrasound assistance according to claim 8, characterized in that: The weight of the titanium powder is equivalent to 1% to 80% of the weight of the finished product.

10. The method for increasing target oxygen vacancies by ultrasound assistance according to claim 9, characterized in that: The weight of the titanium powder is equivalent to 5% to 80% of the weight of the finished product.

11. An indium zinc oxide target, characterized in that: The method is prepared according to any one of claims 1 to 10.