Zinc-based oxide target material and preparation method and application thereof

Abstract

The invention discloses a zinc-based oxide target material as well as a preparation method and application thereof. The zinc-based oxide target material comprises the following raw materials: indium oxide, gallium oxide, tin oxide and zinc oxide quantum dots. The indium oxide quantum dots, the gallium oxide quantum dots, the tin oxide quantum dots and the zinc oxide quantum dots serve as preparation raw materials of the target material, the sintering temperature can be effectively reduced, the density of the target material is improved, and the volatilization rate is reduced. A thin film prepared from the zinc-based oxide target material has higher stability and high mobility.

Description

Technical Field

[0001] The present invention relates to the technical field of target materials, and in particular to a zinc-based oxide target material and a preparation method and application thereof. Background Art

[0002] Thin-film transistors (TFTs) are an important component of optoelectronic devices such as active-matrix liquid crystal displays (AMLCDs) and active-matrix light-emitting diodes (AMOLEDs). As the control element for pixel switches, they perform key driving functions in display operations. In the design of TFTs, researchers are committed to finding better channel layer materials. Metal oxides have been widely studied because of their perfect preparation process, high mobility and good stability.

[0003] The oxide film based on ZnO has the characteristics of fast etching speed and less particle generation. At the same time, due to the low film annealing temperature and good deposition uniformity, it shows excellent performance in new display technology. However, among the existing ZnO-based materials, the migration retention rate of IGZO is only 10cm 2 ·V -1 ·S -1 It is unable to meet the growing demand for high-mobility and high-refresh-rate displays.

[0004] In addition, the use of acetic acid solution as an auxiliary solvent in the related technology is expected to reduce the sintering temperature of the zinc-containing target material, so as to prevent the volatilization of zinc oxide and the imbalance of density and element ratio. However, this method is not suitable for the situation where too many other components make it difficult for zinc oxide to fill the gaps between particles. The large amount of acetic acid used will not only corrode the container, but also cause pore accumulation in the large amount of discharge during the sintering process.

[0005] Therefore, it is necessary to develop a zinc-based oxide target. Summary of the invention

[0006] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the first aspect of the present invention provides a zinc-based oxide target material, which can effectively reduce the sintering temperature, increase the target material density and reduce the volatility. The film prepared by using the zinc-based oxide target material of the present invention has higher stability.

[0007] The second aspect of the present invention also provides a method for preparing a zinc-based oxide target.

[0008] The third aspect of the present invention also provides an application of a zinc-based oxide target.

[0009] According to a first aspect of the present invention, an embodiment provides a zinc-based oxide target material, comprising indium oxide, gallium oxide, tin oxide and zinc oxide quantum dots.

[0010] The zinc-based oxide target provided according to the embodiment of the present invention has at least the following beneficial effects:

[0011] The invention uses indium oxide, gallium oxide, tin oxide and zinc oxide quantum dots as raw materials for preparing the target material, which can effectively reduce the sintering temperature, increase the density of the target material and reduce the volatility. The film prepared by using the zinc-based oxide target material of the invention has higher stability and high mobility.

[0012] Furthermore, the zinc oxide quantum dots of the present invention can easily enter various particle gaps, so that during the heating process, the saturated zinc oxide solution preferentially precipitates small zinc oxide grains from the surface of the zinc oxide quantum dots, continuously filling the particle gaps, thereby achieving the effect of increasing the target material density.

[0013] Furthermore, the outermost empty orbitals of the conduction band composed of indium and tin overlap with each other, providing a favorable transmission path for the shared movement of electrons. Therefore, the prepared film has a higher mobility.

[0014] According to some embodiments of the present invention, the zinc-based oxide target material includes the following raw materials calculated in parts by weight:

[0015] 45-59 parts of indium oxide, 2-16 parts of gallium oxide, 11-19 parts of tin oxide, and 19-39 parts of zinc oxide quantum dots.

[0016] According to some embodiments of the present invention, the zinc-based oxide target material includes the following raw materials calculated in parts by weight:

[0017] 45-59 parts of indium oxide, 5-8 parts of gallium oxide, 13-19 parts of tin oxide, and 19-29 parts of zinc oxide quantum dots.

[0018] According to some embodiments of the present invention, the specific surface area of ​​indium oxide is between 6 m 2 / g to 20m 2 / g.

[0019] According to some embodiments of the present invention, the specific surface area of ​​the tin oxide powder is between 10 m 2 / g to 25m 2 / g.

[0020] According to some embodiments of the present invention, the zinc oxide quantum dots are purchased from the market or prepared by the following method:

[0021] The preparation method is prepared by a sol-gel method: potassium hydroxide and ethylene glycol are mixed and ultrasonically dissolved for later use; zinc acetate dihydrate and ethylene glycol are mixed and heated in a water bath, the reserved solution is mixed therewith, the suspension is centrifuged, dried and ground; zinc oxide quantum dot powder is obtained.

[0022] According to a second aspect of the present invention, an embodiment provides a method for preparing the zinc-based oxide target, comprising the following steps:

[0023] S1. Mix indium oxide, gallium oxide, tin oxide, zinc oxide quantum dots and water, and perform ball milling, drying, grinding and sieving to obtain a mixed powder;

[0024] S2, mixing the mixed powder and acetic acid to obtain slurry, placing the slurry in a mold; applying uniaxial pressure; heating to 300-500° C., maintaining the temperature and pressure; cooling to obtain a target blank; the amount of acetic acid used is 3%-8% of the mass of the mixed powder;

[0025] S3. In an oxygen environment, the target blank is sintered, kept warm, and cooled to obtain a zinc-based oxide target material.

[0026] According to some embodiments of the present invention, in step S1, the particle size of the mixed powder is 300-600 nm.

[0027] According to some embodiments of the present invention, in step S1, the ball milling time is 2000 to 40 hours.

[0028] According to some embodiments of the present invention, in step S1, the particle size of the zirconium beads used for ball milling is 1 to 2 mm.

[0029] According to some embodiments of the present invention, in step S2, the uniaxial pressure is 200-400 MPa.

[0030] According to some embodiments of the present invention, in step S2, the time of heat preservation and pressure preservation is 1 to 2 hours.

[0031] According to some embodiments of the present invention, in step S3, the sintering temperature is 1100-1300°C.

[0032] According to some embodiments of the present invention, in step S3, the insulation time is 3 to 6 hours.

[0033] A third aspect of the present invention provides a use of the above-mentioned zinc-based oxide target in the preparation of optical semiconductor devices.

[0034] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the present invention. DETAILED DESCRIPTION

[0035] The following are specific embodiments of the present invention, and the technical solutions of the present invention are further described in conjunction with the embodiments, but the present invention is not limited to these embodiments.

[0036] Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art.

[0037] Indium oxide and tin oxide: purity requirement ≥99.99%; the specific surface area of ​​indium oxide powder is 6m 2 / g to 20m 2 / g, the specific surface area of ​​tin oxide powder is between 10m 2 / g to 25m 2 / g; commercially available.

[0038] Gallium oxide powder was purchased from Shanghai MacLean Biochemical Technology Co., Ltd., product number G810511.

[0039] Zinc oxide quantum dots: Add 126g of potassium hydroxide to ethylene glycol, sonicate until completely dissolved and set aside; add 66g of zinc acetate dihydrate to 3L of ethylene glycol, heat in a water bath for two hours, mix the set-aside solution with it, centrifuge the suspension, dry it, and grind it to obtain 56.8g of zinc oxide quantum dot powder.

[0040] Example 1

[0041] This example provides a zinc-based oxide target material, the component contents of which are shown in Table 1, and the preparation method thereof is as follows:

[0042] S1. Mix indium oxide powder, gallium oxide powder, tin oxide powder and zinc oxide quantum dots and pour them into a ball mill. Add pure water of the same mass as the powder and mix them by ball milling for 30 hours. The particle size of the zirconium beads used is 1 to 2 mm. The ball mill slurry is dried, ground and sieved to obtain a mixed powder. The particle size of the obtained mixed powder is 300 to 600 nm.

[0043] S2. Place the mixed powder in a mortar, add 3% acetic acid by weight of the powder, grind thoroughly to form a slurry, and place it in a three-inch mold; apply uniaxial pressure of 300 MPa, raise the temperature to 400°C, keep the temperature and pressure for 1.5 hours, and then cool to room temperature to obtain a target blank.

[0044] S3, place the target blank flat in a sintering furnace, introduce oxygen, heat it to 1300°C at a heating rate of 1.5°C / min, keep it warm for 5 hours, and complete the sintering process. Finally, cool it to room temperature with the furnace to obtain a five-element oxide target.

[0045] S4. Place the sintered target material in a lathe and grind it with 400-mesh and 800-mesh grinding wheels respectively. Fix the target material with a smooth surface on a copper back plate using an indium layer to complete the binding process.

[0046] Embodiments 2 to 7

[0047] Examples 2 to 7 provide a series of zinc-based oxide targets, whose component contents are shown in Table 1, and whose preparation methods are the same as those in Example 1.

[0048] Table 1 Examples 1 to 7 (parts by weight)

[0049] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Indium Oxide 50 50 50 45 59 45 59 Gallium Oxide 5 8 11 16 2 5 8 Tin Oxide 13 13 13 11 19 13 19 Zinc Oxide Quantum Dots 29 29 29 39 19 19 29

[0050] Comparative Example 1

[0051] This example provides a zinc-based oxide target material, the component dosage and preparation method of which are basically the same as those in Example 2, except that zinc oxide is used instead of zinc oxide quantum dots.

[0052] Comparative Example 2

[0053] This example provides a zinc-based oxide target material, the component dosage and preparation method of which are basically the same as those in Example 2, except that an equal amount of indium oxide is used to replace gallium oxide.

[0054] Performance Testing

[0055] The relative density of the target materials prepared in the embodiments of the present invention and the comparative examples was measured by the Archimedean drainage method. The volatility is the weight loss ratio before and after sintering, and the calculation formula is:

[0056] Relative density = actual density / theoretical density × 100%;

[0057] Volatility rate = (weight before sintering - weight after sintering / weight before sintering) x 100%.

[0058] Target coating performance test method: The cleaned glass substrate is coated sequentially, with ITO as the electrode, aluminum oxide as the insulating layer, and the oxide film of each embodiment and comparative example as the channel layer material, to prepare a bottom-gate coplanar TFT device, and the electrical characteristics of the TFT device of each test group are tested using a Keythley 2636 semiconductor tester. The subthreshold swing (SS) can measure the trap state density of the device. The lower the SS value, the higher the stability of the device. The results are shown in Table 2.

[0059] Table 2 Examples 1 to 7 and Comparative Examples 1 to 2

[0060]

[0061] From the data in Table 2, it can be seen that the reasonable proportion of oxide powder can not only obtain a target with high density, but also make the device at the target application end have high mobility and high stability. Compared with zinc oxide powder in the traditional cold sintering process, zinc oxide quantum dots as raw materials make the ceramic target have higher density, and can reduce the use of acetic acid and increase relative density.

[0062] The above is a detailed description of the embodiments of the present invention, but the present invention is not limited to the above embodiments. Various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. A zinc-based oxide target, characterized in that: Including raw materials: indium oxide, gallium oxide, tin oxide and zinc oxide quantum dots.

2. The zinc-based oxide target according to claim 1, characterized in that: The following raw materials are included in parts by weight: 45-59 parts of indium oxide, 2-16 parts of gallium oxide, 11-19 parts of tin oxide, and 19-39 parts of zinc oxide quantum dots.

3. The zinc-based oxide target according to claim 1, characterized in that: The specific surface area of ​​indium oxide is 6 m 2 / g to 20m 2 / g.

4. The zinc-based oxide target according to claim 1, characterized in that: The specific surface area of ​​tin oxide powder is between 10m 2 / g to 25m 2 / g.

5. The method for preparing a zinc-based oxide target according to any one of claims 1 to 4, characterized in that: The steps include: S1. Mix indium oxide, gallium oxide, tin oxide, zinc oxide quantum dots and water, and perform ball milling, drying, grinding and sieving to obtain a mixed powder; S2, mixing the mixed powder and acetic acid to obtain a slurry, placing the slurry in a mold; applying uniaxial pressure; Raise the temperature to 300-500℃, keep the temperature and pressure; Cooling to obtain a target blank; the amount of acetic acid used is 3% to 8% of the mass of the mixed powder; S3. In an oxygen environment, the target blank is sintered, kept warm, and cooled to obtain a zinc-based oxide target material.

6. The preparation method according to claim 5, characterized in that: In step S1, the particle size of the mixed powder is 300-600 nm.

7. The preparation method according to claim 5, characterized in that: In step S2, the uniaxial pressure is 200-400 MPa.

8. The preparation method according to claim 5, characterized in that: In step S3, the sintering temperature is 1100-1300°C.

9. The preparation method according to claim 5, characterized in that: In step S3, the insulation time is 3 to 6 hours.

10. Use of the zinc-based oxide target material according to any one of claims 1 to 4 in the preparation of optical semiconductor devices.

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