A high-density target material and a method of manufacturing the same

Abstract

The application belongs to the technical field of semiconductors, and discloses a preparation method of high-density target material, in which a target material precursor and titanium powder are placed in the same environment without contacting each other under vacuum, and the target material is obtained by heating and sintering; the target material precursor is suspended during sintering; the relative density of the target material is greater than 99%, and the absolute density is equal to or greater than 7.1 g / cm 3 The method of the application is suitable for high-density target material with a relative density of 99%, can effectively increase oxygen vacancies, and prevents target material from warping.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor, in particular to a high-density target material and a preparation method thereof. BACKGROUND

[0002] SnO2 is a wide-band metal oxide semiconductor material with a direct band gap. SnO2 ceramic material has always been a research hotspot. It has broad application prospects in gas sensing, liquid crystal display, optical detector, solar cell, photocatalysis, electrocatalysis, protective coating and other fields. In theory, pure SnO2 thin film has poor conductivity. Generally, when preparing SnO2 target material, oxygen vacancies are generated in SnO2 by doping or controlling sintering atmosphere, so as to greatly improve the conductivity of SnO2 and better apply it to the field of sputtering.

[0003] 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 channel structure passing through the stack structure in a vertical direction, wherein forming the channel 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] The 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] The applicant's prior application CN116216770A discloses a preparation method of 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 obtained in step 1 to obtain a yellow IZO precursor powder; step 3: adding a reducing agent to the yellow IZO precursor powder obtained in step 2, shearing by an emulsifying shearing machine, and then adding to a high-pressure kettle, and then performing heat treatment and solid-liquid separation to obtain a blue precipitate; and step 4: washing, drying and obtaining the blue IZO powder from the blue precipitate obtained in step 3. The blue IZO powder prepared by the method has a high oxygen vacancy concentration, thereby improving the carrier concentration and conductivity.

[0006] The 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. The scheme is suitable for low-temperature sintering materials and does not need high-temperature sintering, and there is no problem of rapid volatilization of the reducing agent.

[0007] In another prior application of the applicant, the oxygen vacancies of the target material are improved by using titanium as an oxygen adsorbent.

[0008] The method places the target material on the supporting plate and sinter it with titanium powder in the same space without contacting each other, which is suitable for low-density target material such as target material with density of 96% and 97%.

[0009] For high-density target material, it is difficult to empty the oxygen vacancies, and the applicant has tested that the methods such as stepwise heating and stepwise cooling cannot solve the problem of not improving the oxygen vacancies.

[0010] At the same time, the high-density target material has a defect that the target material is easy to warp by using the above scheme.

[0011] Therefore, the technical problem solved by the present application is how to improve the oxygen vacancies of the high-density target material. SUMMARY

[0012] One of the purposes of the present application is to provide a preparation method of high-density target material, and the method of the present application is suitable for high-density target material with relative density of 99%, which can effectively improve the oxygen vacancies and prevent the target material from warping.

[0013] At the same time, the present application also provides the high-density target material.

[0014] In the case where no special description is made in the present application, M is mol / L, and % is mass percentage.

[0015] To achieve the above purpose, the present application provides a preparation method of high-density target material, which places the target material precursor and titanium powder in the same environment without contacting each other in a vacuum environment, and then sintering to obtain the target material.

[0016] The target material precursor is suspended during sintering, and the relative density of the target material is greater than 99%.

[0017] The vacuum environment of the present application does not and absolutely cannot reach absolute vacuum, and the vacuum environment of the present application refers to the lowest vacuum degree that can be allowed in industry, such as 0.01Pa-0.006Pa.

[0018] As an alternative means, a small amount of inert gas can be filled, so that the vacuum degree does not need to be very low.

[0019] In the above preparation method of high-density target material, the target material is indium tin oxide, and the absolute density of the target material is equal to or greater than 7.1g / cm 3 .

[0020] If the target material is indium tin oxide, the molar ratio of indium oxide and tin oxide is 96-99:1-4.

[0021] In the preparation method of the high-density target material, the relative density of the target material is greater than 99.5%, preferably greater than 99.8%.

[0022] In the preparation method of the high-density target material, the target precursor is suspended by the supporting bracket so that the bottom surface of the target precursor is separated from the wall of the environment.

[0023] In the preparation method of the high-density target material, the target material is an indium tin oxide target material; and the molar ratio of indium oxide to tin oxide in the target precursor is 96-99:1-4.

[0024] In some embodiments of the present application, the molar ratio of indium oxide to tin oxide in the target precursor is 96:4, 97:3, 98:2 or 99:1.

[0025] The sintering temperature is 1400-1600℃, and the holding time is 10-12h.

[0026] In some embodiments of the present application, the sintering temperature is 1400℃, 1420℃, 1440℃, 1460℃, 1480℃, 1500℃, 1520℃, 1540℃, 1560℃, 1580℃ or 1600℃.

[0027] During sintering, the heating rate is 0.5-1.5℃ / min.

[0028] In some embodiments of the present application, the heating rate is 0.5℃ / min, 0.6℃ / min, 0.7℃ / min, 0.8℃ / min, 0.9℃ / min, 1.0℃ / min, 1.1℃ / min, 1.2℃ / min, 1.3℃ / min, 1.4℃ / min or 1.5℃ / min.

[0029] In the preparation method of the high-density target material, the preparation method of the target precursor is as follows:

[0030] One or more metal oxides, a dispersant and a binder are mixed to prepare slurry, which is ground, sprayed to obtain powder, and the powder is subjected to die pressing and cold isostatic pressing to obtain a target blank, and the target blank is heated and degreased to obtain the target precursor.

[0031] In the preparation method of the high-density target material, the target precursor is an indium tin oxide target precursor.

[0032] The preparation method of the indium tin oxide target precursor is as follows:

[0033] Step 1: Pour the tin oxide powder and the first dispersant into a slurry barrel containing pure water, uniformly disperse, and then obtain slurry one by wet grinding.

[0034] Step 2: the weighed indium oxide powder, pure water and the second dispersing agent are added into slurry one, and after being uniformly dispersed, slurry two is obtained through wet grinding;

[0035] Step 3: the binder is added into the obtained slurry two, and after being uniformly dispersed, slurry three is obtained through wet grinding;

[0036] Step 4: the slurry three is granulated by spraying, and then is mixed and screened to obtain the indium tin oxide mixed powder;

[0037] Step 5: the indium tin oxide mixed powder is subjected to die pressing and cold isostatic pressing to obtain the indium tin oxide target blank;

[0038] Step 6: the indium tin oxide target blank is subjected to heat treatment, and the temperature is controlled at 400-600 DEG C for degreasing treatment.

[0039] In the preparation method of the high-density target material, the weight of the titanium powder is 0.1%-100% of the weight of the target material, preferably, the weight of the titanium powder is 1%-80% of the weight of the target material; preferably, the weight of the titanium powder is 5%-80% of the weight of the target material.

[0040] In the preparation method of the high-density target material, the method is carried out in a sintering furnace, a supporting frame is placed in the sintering furnace, and then a layer of tin oxide or aluminum oxide fine sand is laid on the supporting frame in contact with the target precursor, the target precursor is placed on the supporting frame, a layer of supporting plate is covered, and a quartz boat filled with titanium powder is placed on the supporting plate.

[0041] Meanwhile, the application also discloses a high-density target material prepared by the method.

[0042] Compared with the prior art, the application has the following advantages:

[0043] 1. The sintering method can produce more oxygen vacancies on the surface of the target material, thereby improving the mobility.

[0044] 2. The method of the application can make the oxygen better escape.

[0045] 3. The supporting frame is used to: the traditional sintering method is to place the target material on the supporting plate for sintering, the supporting plate has a large contact area with the target blank, which can affect the shrinkage of the target material at high temperature, and the heat conduction effect is not good, so the density of the front and back surfaces of the target material is not uniform. The supporting frame has a small contact area and good heat conduction capacity, and the bottom is not blocked, which is beneficial to the escape of oxygen. BRIEF DESCRIPTION OF DRAWINGS

[0046] Figure 1 is the front view of the supporting frame of the application;

[0047] Figure 2 is a top view of the supporting frame of the present application. DETAILED DESCRIPTION

[0048] The present application will be further described in conjunction with the embodiments, but does not constitute any limitation to the present application, any limited number of modifications made within the scope of the claims of the present application is still within the scope of the claims of the present application.

[0049] In order to illustrate the technical content of the present application, the following further describes in conjunction with the embodiments.

[0050] Before the relevant description of the embodiments of the present application is made, the structure of the supporting frame is introduced generally;

[0051] Reference Figure 1 and 2 The supporting frame comprises a supporting frame 2 and a supporting leg 1, the supporting leg is connected to the supporting frame; the surface of the supporting frame can be a mesh structure, specifically composed of an inner ring 3, an outer ring 4 and a plurality of spokes 5 connecting the inner ring and the outer ring; the supporting leg is connected to the inner ring and the outer ring; the supporting leg maintains a height of at least 5 cm; in actual application, the outer contour area of the supporting frame can be smaller or larger than the projection area of the target material, as long as it can support the target material; but generally, it is recommended that the outer contour area of the supporting frame is slightly larger than the projection area of the target material, because if it cannot be fully supported, problems such as target material warping may occur.

[0052] In the present application, the height of the supporting leg is 5 cm; the outer contour area of the supporting frame is adapted to the projection area of the target material. The contact area between the supporting frame and the target material is not more than 20% of the projection area of the target material.

[0053] Example 1

[0054] Preparation of high-density indium tin oxide target material

[0055] (1) Indium oxide and tin oxide powder were weighed according to the ratio of 97:3 for standby.

[0056] (2) A certain amount of pure water was added to the slurry barrel, and the tin oxide powder and PVP weighed in step 1 were sequentially added to the slurry barrel for pre-dispersion, the dispersion time was 30 min, and the dispersion rotation speed was 100 rpm, wherein the PVP accounted for 4% of the total mass of the added tin oxide powder, pure water and PVP.

[0057] (3) The slurry obtained in step 2 was pumped into a sand mill with a pneumatic diaphragm pump for grinding. The grinding time was 12 h, and the grinding rotation speed was 1500 r / min, to obtain slurry one.

[0058] (4) The slurry obtained in step 3 is dispersed by adding indium oxide powder and PVP, and the dispersion time is 30 min and the dispersion rotation speed is 100 rpm. Then the obtained slurry is pumped into a sand mill by a pneumatic diaphragm pump for grinding, and the grinding time is 8 h and the grinding rotation speed is 1500 rpm to obtain slurry 2. The PVP accounts for 4% of the total mass of the added indium oxide powder and PVP.

[0059] (5) The slurry 2 obtained in step 4 is pre-dispersed by adding PVA, and the pre-dispersion time is 30 min and the pre-dispersion rotation speed is 100 rpm. Then the slurry is pumped into a sand mill by a pneumatic diaphragm pump for grinding, and the grinding time is 2 h and the grinding rotation speed is 1500 rpm to obtain slurry 3. The binder accounts for 10% of the total mass of the added indium oxide powder, tin oxide and binder.

[0060] (6) The slurry 3 obtained in step 5 is pumped into a spray drying tower for spray granulation, and then mixed and sieved to obtain an indium tin oxide mixed powder. The outlet air temperature is 75°C and the atomizer frequency is 120 Hz.

[0061] (7) The mixed powder obtained in step 6 is formed by molding and cold isostatic pressing to obtain an indium tin oxide target blank

[0062] (8) The target blank obtained in step 7 is placed in a sintering furnace for debinding heat treatment, and the temperature is controlled at 500°C at a heating rate of 0.5 / min in an air atmosphere, and the holding time is 8 h, and then cooled to room temperature to remove the additives and other organic matters in the target blank.

[0063] (9) An alumina fine sand with a purity of not less than 98% and a particle size of 0.15-0.25 mm is uniformly laid on a supporting frame on the supporting plate of the sintering furnace, and the thickness is about 2 mm. The debound target material obtained in step (8) is placed on the supporting frame, and then covered with a supporting plate.

[0064] (10) A quartz boat containing titanium powder is placed on the supporting plate, and the amount of titanium powder is 80% of the weight of the target material. The titanium powder is used to absorb oxygen in the indium tin oxide lattice under vacuum conditions to generate more oxygen vacancies, thereby improving the carrier concentration and conductivity.

[0065] (11) The furnace door is closed for vacuum sintering, and the heating rate is 1°C / min. The temperature is raised to 1450°C and held for 10 h to obtain a target material. The appearance detection result of the target material is: no obvious warping.

[0066] (12) The relative density of the target material obtained in step 11 is 99.71%, and the absolute density is 7.132 g / cm 3 , and the oxygen vacancy concentration is 6.75E+21 cm -3.

[0067] (13) The obtained target material is used in a sputtering coating machine, Ar / O2 / H2 is used as working gas, sputtering power is 100w, pressure is 0.4Pa, substrate temperature is 200℃, gas flow is 1%O2 / 1.8%H2, pre-sputtering time is 300s, sputtering time is 380s, and the migration rate of the glass sheet is measured to be 21.2cm 2 / (V·S).

[0068] Example 2

[0069] Preparation of high-density indium tin oxide target material

[0070] (1) Indium oxide and tin oxide powders are weighed according to the molar ratio of 97:3 for standby.

[0071] (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 30min, the dispersion speed is 100rpm, and the PVP accounts for 4% of the total mass of the added tin oxide powder, pure water and PVP.

[0072] (3) The slurry obtained in step 2 is pumped into a sand mill by a pneumatic diaphragm pump for grinding. The grinding time is 12h, the grinding speed is 1500r / min, and the slurry one is obtained.

[0073] (4) The slurry one obtained in step 3 is added with indium oxide powder and PVP for dispersion, the dispersion time is 30min, the dispersion speed is 100rpm. Then the obtained slurry is pumped into a sand mill by a pneumatic diaphragm pump for grinding, the grinding time is 8h, the grinding speed is 1500rpm, and the slurry two is obtained. The PVP accounts for 4% of the total mass of the added indium oxide powder and PVP.

[0074] (5) The slurry two obtained in step 4 is added with PVA for pre-dispersion, the pre-dispersion time is 30min, the dispersion speed is 100rpm, and then the slurry is pumped into a sand mill by a pneumatic diaphragm pump for grinding, the grinding time is 2h, the grinding speed is 1500rpm, 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.

[0075] (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 indium tin oxide mixed powder. The air outlet temperature is 75℃, and the atomizer frequency is 120Hz.

[0076] (7) The mixed powder obtained in step 6 is formed by molding and cold isostatic pressing to obtain an indium tin oxide target blank

[0077] (8) Put the target embryo obtained in step 7 into a sintering furnace for debinding heat treatment, in an air atmosphere, at a temperature control rate of 0.5 / min, at 500℃, for 8h, and then cooled to room temperature, to remove the additives and other organic matter in the target embryo.

[0078] (9) Put a sintering frame on the sintering plate of the sintering furnace, and then evenly spread a layer of alumina sand with a thickness of about 2mm and a purity of not less than 98% and a particle size of 0.15-0.25mm on the sintering frame. Put the debound target material obtained in step (8) on the sintering frame, and cover it with a sintering plate.

[0079] (10) Put a quartz boat containing elemental titanium powder on the sintering plate, wherein the amount of elemental titanium powder is 80% of the weight of the target material. The elemental titanium absorbs the oxygen in the indium tin oxide lattice under vacuum conditions to generate more oxygen vacancies, thereby increasing the carrier concentration and conductivity.

[0080] (11) Close the furnace door and perform vacuum sintering at a temperature control rate of 1℃ / min, and then heat to 1500℃ and maintain for 10h to obtain the target material. The appearance detection result of the target material is: no obvious warping.

[0081] (12) The relative density of the target material obtained in step 11 is 99.74%, and the absolute density is 7.136g / cm 3 , and the oxygen vacancy concentration is 7.18E+21cm -3 .

[0082] (13) Use the sputtering coating machine to perform sputtering using Ar / O2 / H2 as the working gas, with a sputtering power of 100w, a pressure of 0.4Pa, a substrate temperature of 200℃, a gas flow of 1%O2 / 1.8%H2, a pre-sputtering time of 300s, and a sputtering time of 380s. The measured glass sheet mobility is 22.37cm 2 / (V·S).

[0083] Example 3

[0084] The molar ratio of indium oxide and tin oxide powder is 98:2.

[0085] The relative density of the obtained target material is 99.64%, the absolute density is 7.128g / cm 3 , the oxygen vacancy concentration is 6.79E+21cm -3 , and the appearance detection result of the target material is: no obvious warping.

[0086] The film is coated by the method of step 13, and the measured glass sheet mobility is 18.16cm 2 / (V·S).

[0087] Example 4

[0088] The molar ratio of indium oxide and tin oxide powder is 99:1.

[0089] The relative density of the obtained target material is 99.67%, the absolute density is (7.130) g / cm 3 , the oxygen vacancy concentration is 6.86E+21 cm -3 , and the appearance detection result of the target material is: no obvious warping.

[0090] The film plating is performed by the method of step 13, and the glass sheet mobility is measured to be 18.16 cm 2 / (V·S).

[0091] Example 5

[0092] The amount of elemental titanium powder is 40% of the weight of the target material.

[0093] The relative density of the obtained target material is 99.68%, the absolute density is 7.132 g / cm 3 , the oxygen vacancy concentration is 4.13E+21 cm -3 , and the appearance detection result of the target material is: no obvious warping.

[0094] The film plating is performed by the method of step 13, and the glass sheet mobility is measured to be 20.62 cm 2 / (V·S).

[0095] Example 6

[0096] The amount of elemental titanium powder is 10% of the weight of the target material.

[0097] The relative density of the obtained target material is 99.71%, the absolute density is 7.134 g / cm 3 , the oxygen vacancy concentration is 2.64E+21 cm -3 , and the appearance detection result of the target material is: no obvious warping.

[0098] The film plating is performed by the method of step 13, and the glass sheet mobility is measured to be 20.23 m 2 / (V·S).

[0099] Example 7

[0100] The calcination temperature is 1400°C, and the calcination time is 12h.

[0101] The relative density of the obtained target material is 99.54%, the absolute density is (7.120) g / cm 3, oxygen vacancy concentration 5.76E+21 cm -3 The appearance detection result of the target material is: no obvious warping.

[0102] The film plating was performed by the method of step 13, and the migration rate of the glass sheet was measured to be 17.53 cm 2 / (V·S).

[0103] Example 8

[0104] The calcination temperature was 1600℃, and the calcination time was 10h.

[0105] The relative density of the obtained target material was 99.62%, and the absolute density was 7.127g / cm 3 , oxygen vacancy concentration 6.23E+21 cm -3 The appearance detection result of the target material is: no obvious warping.

[0106] The film plating was performed by the method of step 13, and the migration rate of the glass sheet was measured to be 18.14 cm 2 / (V·S).

[0107] Comparative Example 1

[0108] (1) Indium oxide and tin oxide powder were weighed according to the molar ratio of 97:3 for standby.

[0109] (2) A certain amount of pure water was added to the slurry barrel, and the tin oxide powder and PVP weighed in step 1 were sequentially added to the slurry barrel for pre-dispersion, the dispersion time was 30 min, and the dispersion rotation speed was 100 rpm, wherein the PVP accounted for 4% of the total mass of the added tin oxide powder, pure water and PVP.

[0110] (3) The slurry obtained in step 2 was pumped into a sand mill by a pneumatic diaphragm pump for grinding. The grinding time was 12h, and the grinding rotation speed was 1500r / min, and slurry one was obtained.

[0111] (4) Indium oxide powder and PVP were added to the slurry one obtained in step 3 for dispersion, the dispersion time was 30 min, and the dispersion rotation speed was 100 rpm. Then the obtained slurry was pumped into a sand mill by a pneumatic diaphragm pump for grinding, the grinding time was 8h, and the grinding rotation speed was 1500rpm, and slurry two was obtained. The PVP accounted for 4% of the total mass of the added indium oxide powder and PVP.

[0112] (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, 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, tin oxide and binder added.

[0113] (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 an indium tin oxide mixed powder. The air outlet temperature is 75°C and the atomizer frequency is 120 Hz.

[0114] (7) The mixed powder obtained in step 6 is formed by die pressing and cold isostatic pressing to obtain an indium tin oxide target blank

[0115] (8) The target blank obtained in step 7 is placed into a sintering furnace for debinding heat treatment, the temperature is controlled at 500°C at a heating rate of 0.5 / min in an air atmosphere, and the temperature is kept for 8 h before cooling to room temperature to remove the additives and other organic matters in the target blank.

[0116] (9) The target blank obtained in step 8 is placed into a sintering furnace for sintering at a heating rate of 1°C / min, and the temperature is kept for 10 h after being heated to 1500°C. A target material is obtained, which has a certain warpage with a size measurement of 0.8 mm.

[0117] (10) The density of the target material obtained in step 9 is tested, and the relative density is 99.42% and the absolute density is 7.114 g / cm 3 . -3 .

[0118] (11) 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 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 14.18 cm 2 / (V·S).

[0119] Comparative Example 2

[0120] (1) Indium oxide and tin oxide powder are weighed according to a molar ratio of 97:3 for standby use.

[0121] (2) A certain amount of pure water is added to a slurry tank, and the tin oxide powder and PVP weighed in step 1 are sequentially added to the slurry tank 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.

[0122] (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 1 is obtained.

[0123] (4) The slurry 1 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 2 is obtained. The PVP accounts for 4% of the total mass of the added indium oxide powder and PVP.

[0124] (5) The slurry 2 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 3 is obtained. The binder accounts for 10% of the total mass of the added indium oxide powder, tin oxide and binder.

[0125] (6) The slurry 3 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.

[0126] (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

[0127] (8) The target blank obtained in step 7 is placed in a sintering furnace for debinding heat treatment. The temperature is controlled at 500℃ at a heating rate of 0.5 / min in an air atmosphere. After heat preservation for 8 h, the temperature is cooled to room temperature to remove the additives and other organic matters in the target blank.

[0128] (9) A layer of alumina fine sand with a thickness of about 1.5-2.5 mm is uniformly laid on the sintering furnace supporting plate. The purity of the fine sand is not less than 98%, and the particle size is between 0.15-0.25 mm.

[0129] (10) The target blank after heat treatment in step 8 is placed on the laid alumina fine sand. A supporting plate is covered, and a quartz boat filled with titanium powder is placed on the supporting plate. The purity of the titanium powder is 99.99%, and the weight is 80% of the weight of the target blank.

[0130] (11) The furnace door is closed for vacuum sintering. The heating rate is 1℃ / min. After heating to 1500℃, the temperature is kept for 10 h to obtain the target material. The target material has a certain warping, and the gauge measurement is 0.4 mm.

[0131] (12) The density of the target material obtained in step 11 is tested, and the relative density is 99.39%, and the absolute density is 7.108 g / cm 3 , and the oxygen vacancy concentration is 5.76E+15 cm -3 .

[0132] (13) The obtained target material is used in a sputtering coating machine, Ar / O2 / H2 is used as the working gas, 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 mobility of the glass sheet is measured to be 15.91 cm 2 / (V·S).

[0133] Comparative Example 3

[0134] (1) Tin oxide and molybdenum oxide powders are weighed according to a molar ratio of 99.5:0.5 for standby use.

[0135] (2) A certain amount of pure water is added to the slurry barrel, and the molybdenum oxide powder and PVP weighed in step (1) are sequentially added to the slurry barrel for pre-dispersion, the dispersion time is 30 min, and the dispersion rotation speed is 100 rpm. The PVP accounts for 4% of the total mass of the added molybdenum oxide powder, pure water and PVP.

[0136] (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 rotation speed is 1500 r / min. Slurry one is obtained.

[0137] (4) Tin oxide powder and PVP are added to the slurry one obtained in step 3 for dispersion, the dispersion time is 30 min, and the dispersion rotation speed is 100 rpm. Then the obtained slurry is pumped into a sand mill with a pneumatic diaphragm pump for grinding, the grinding time is 8 h, and the grinding rotation speed is 1500 rpm. Slurry two is obtained. The PVP accounts for 4% of the total mass of the added tin oxide powder and PVP.

[0138] (5) PVA is added to the slurry two obtained in step 4 for pre-dispersion, the pre-dispersion time is 30 min, and the dispersion rotation speed is 100 rpm. Then the slurry is pumped into a sand mill with a pneumatic diaphragm pump for grinding, the grinding time is 2 h, and the grinding rotation speed is 1500 rpm. Slurry three is obtained. The binder accounts for 10% of the total mass of the added tin oxide powder, molybdenum oxide and binder.

[0139] (6) The slurry three obtained in step 5 is pumped into a spray drying tower for spray granulation, then mixed and sieved to obtain tin oxide doped molybdenum oxide mixed powder. The outlet air temperature is 75°C, and the atomizer frequency is 120 Hz.

[0140] (7) The mixed powder obtained in step 6 is formed by die pressing and cold isostatic pressing to obtain a tin oxide doped molybdenum oxide target blank

[0141] (8) The target blank obtained in step 7 is placed in a sintering furnace for debinding heat treatment, and the temperature is raised at a rate of 0.5 / min, the temperature is controlled at 500℃, and after 8h of heat preservation, it is cooled to room temperature to remove the additives and other organic matters in the target blank.

[0142] (9) A layer of alumina fine sand with a thickness of about 1.5-2.5mm is uniformly laid on the sintering furnace supporting plate, and the purity of the fine sand is not less than 98%, and the particle size is between 0.15-0.25mm.

[0143] (10) The target blank after heat treatment in step 8 is placed on the laid alumina fine sand, a layer of supporting plate is covered, and a quartz boat filled with titanium powder is placed on the supporting plate, wherein the purity of the titanium powder is 99.99%, and the weight of the titanium powder is 80% of the weight of the target blank.

[0144] (11) The furnace door is closed for vacuum sintering, the temperature is raised at a rate of 1℃ / min, and after the temperature is raised to 1400℃, it is heat preserved for 10h to obtain the target material, and the appearance detection result of the target material is: no obvious warping.

[0145] (12) The density of the target material obtained in step 11 is tested, and the relative density is 98.21%, and the absolute density is 6.30g / cm 3 , and the oxygen vacancy concentration is 6.31E+17cm -3 .

[0146] Comparative Example 4

[0147] (1) Tin oxide and molybdenum oxide powders are weighed according to the molar ratio of 99.5:0.5 for standby.

[0148] (2) A certain amount of pure water is added to the slurry barrel, and the molybdenum oxide powder and PVP weighed in step (1) are sequentially added to the slurry barrel for pre-dispersion, the dispersion time is 30min, and the dispersion rotation speed is 100rpm, wherein the PVP accounts for 4% of the total mass of the added molybdenum oxide powder, pure water and PVP.

[0149] (3) The slurry obtained in step 2 is pumped into the sand mill by a pneumatic diaphragm pump for grinding. The grinding time is 12h, and the grinding rotation speed is 1500r / min to obtain slurry one.

[0150] (4) The slurry obtained in step 3 is dispersed by adding tin oxide powder and PVP, and the dispersion time is 30 min and the dispersion rotation speed is 100 rpm. Then the obtained slurry is pumped into a sand mill by a pneumatic diaphragm pump for grinding, and the grinding time is 8 h and the grinding rotation speed is 1500 rpm to obtain slurry 2. The PVP accounts for 4% of the total mass of the added tin oxide powder and PVP.

[0151] (5) The slurry 2 obtained in step 4 is pre-dispersed by adding PVA, and the pre-dispersion time is 30 min and the pre-dispersion rotation speed is 100 rpm. Then the slurry is pumped into a sand mill by a pneumatic diaphragm pump for grinding, and the grinding time is 2 h and the grinding rotation speed is 1500 rpm to obtain slurry 3. The binder accounts for 10% of the total mass of the added tin oxide powder, molybdenum oxide and binder.

[0152] (6) The slurry 3 obtained in step 5 is pumped into a spray drying tower for spray granulation, and then mixed and sieved to obtain a tin oxide doped molybdenum oxide mixed powder. The outlet air temperature is 75°C and the atomizer frequency is 120 Hz.

[0153] (7) The mixed powder obtained in step 6 is formed by molding and cold isostatic pressing to obtain a tin oxide doped molybdenum oxide target blank

[0154] (8) The target blank obtained in step 7 is placed in a sintering furnace for debinding heat treatment, and the temperature is controlled at 500°C at a heating rate of 0.5 / min in an air atmosphere, and after 8 h of heat preservation, it is cooled to room temperature to remove the additives and other organic matters in the target blank.

[0155] (9) Put a supporting frame on the supporting plate of the sintering furnace, and then evenly spread a layer of alumina fine sand on the supporting frame, with a thickness of about 1.5-2.5 mm, a purity of not less than 98%, and a particle size of 0.15-0.25 mm. The debound target material obtained in step (8) is placed on the supporting frame, and a supporting plate is covered on it.

[0156] (10) 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 material. For example, the metal titanium absorbs the oxygen in the indium tin oxide lattice under vacuum conditions to produce more oxygen vacancies, thereby improving the carrier concentration and conductivity.

[0157] (11) Close the furnace door for vacuum sintering, and the heating rate is 1°C / min. After heating to 1400°C, heat preservation for 10 h to obtain the target material. The appearance detection result of the target material is: no obvious warping.

[0158] (12) The density of the target material obtained in step 11 is tested, and the relative density is 98.18%, and the absolute density is 6.297 g / cm 3, oxygen vacancy concentration 6.47E+17cm -3 .

[0159] Result analysis

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

[0161] 1. By testing example 7, example 2, example 1, example 8, it can be seen that with the gradual increase of sintering temperature, the oxygen vacancy concentration first increases and then decreases, and the mobility first increases and then slowly decreases. It can be concluded that in the case of suspended sintering, the temperature control at 1450-1500℃ is the most appropriate temperature.

[0162] At the same time, it can be found that the sintering temperature has no obvious influence on the forming.

[0163] 2. It can be seen from example 1, example 3 and example 4 that the change of the molar ratio of indium and tin has little effect on the oxygen vacancy, but has a significant effect on the actual application mobility, so the best molar ratio should be controlled at 97:3.

[0164] 3. It can be seen from example 1, comparative example 1 and comparative example 2 that whether there is titanium powder, if not using the shelf, it has obvious influence on the warping, if there is elemental titanium, the oxygen vacancy density is doubled.

[0165] 4. It can be seen from the comparison of comparative example 3 and comparative example 4 that for low-density target material, whether to use the supporting frame has no obvious influence on the target warping and oxygen vacancy, that is, the method of the present application is especially suitable for high-density target material.

[0166] The selection of titanium is the elemental titanium obtained after repeated optimization of the project. Titanium oxide has the following characteristics: high temperature stability, not easy to gasify and sublimate; 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, and the latter ensures that it can effectively absorb oxygen;

[0167] Such as iron, which will decompose above 1200℃; 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℃, carbon powder is extremely easy to fly and easily contaminates the target.

[0168] From the above analysis, it can be seen that for high-density target material, selecting suspended sintering accompanied by titanium powder absorbing oxygen is an effective means to improve oxygen vacancy and control deformation.

[0169] The embodiments presented herein are only examples selected from combinations of all possible embodiments. The appended claims should not be limited to the embodiments described herein. Subranges of the values included in the ranges of values disclosed herein are also contemplated as are variations to the disclosed ranges of values.

Claims

1. A method of producing a high-density target material, characterized by, The target precursor and the titanium powder are placed in the same environment without contacting each other in a vacuum environment, and then the target is obtained by sintering at a high temperature; The target precursor is suspended during sintering; the target is an indium tin oxide target, the relative density of the target is greater than 99%, and the absolute density is equal to or greater than 7.1 g / cm 3 ; The molar ratio of indium oxide to tin oxide in the target precursor is 96-99:1-4; The sintering temperature is 1400-1600 DEG C, and the holding time is 10-12 hours; The heating rate during sintering is 0.5-1.5 DEG C / min; The target precursor is suspended by a supporting bracket so that the bottom surface of the target precursor is separated from the wall of the environment.

2. The method of producing a high-density target material according to claim 1, wherein The relative density of the target is greater than 99.5%.

3. The method of producing a high-density target material according to Claim 1, wherein The target precursor is an indium tin oxide target precursor; The preparation method of the indium tin oxide target precursor comprises the following steps: Step 1: tin oxide powder and a first dispersing agent are poured into a slurry barrel containing pure water, and then the slurry one is obtained by wet grinding after uniform dispersion; Step 2: weighed indium oxide powder, pure water and a second dispersing agent are added to the slurry one, and then the slurry two is obtained by wet grinding after uniform dispersion; Step 3: a binder is added to the obtained slurry two, and then the slurry three is obtained by wet grinding after uniform dispersion; Step 4: the slurry three is granulated by spraying, and then mixed and sieved to obtain an indium tin oxide mixed powder; Step 5: the indium tin oxide mixed powder is subjected to die pressing and cold isostatic pressing to obtain an indium tin oxide target blank; Step 6: the indium tin oxide target blank is subjected to heat treatment, and the temperature is controlled at 400-600 DEG C for defatting treatment.

4. The method of producing a high-density target material according to Claim 1, characterized by, The weight of the titanium powder is 0.1%-100% of the weight of the target.

5. The method of producing a high-density target material according to claim 4, wherein The weight of the titanium powder is 1%-80% of the weight of the target.

6. The method of producing a high density target material according to claim 4, wherein The weight of the titanium powder is 5%-80% of the weight of the target.

7. The method of producing a high density target material according to claim 1, wherein The method is carried out in a sintering furnace, a supporting frame is placed in the sintering furnace, a layer of tin oxide or aluminum oxide fine sand is laid on the position of the supporting frame which contacts the target precursor, the target precursor is placed on the supporting frame, a layer of supporting plate is covered, and a quartz boat containing titanium powder is placed on the supporting plate.

8. A high density target material, characterized by, The target is prepared by the method according to any one of claims 1-7.

Images