Molybdenum oxide-based target material for BM material in display field and preparation method of molybdenum oxide-based target material

Abstract

The invention relates to the technical field of target materials, and provides a molybdenum oxide-based target material for a BM material in the display field and a preparation method of the molybdenum oxide-based target material. MoO3 serves as a main component and provides a basic structure and functions of the target material; moO2 is introduced, so that the conductivity of the target material can be improved, the resistivity is reduced, and meanwhile, the density of the target material is improved; the metal molybdenum is added, so that the conductivity and the mechanical strength of the target material can be further improved; the doped rare earth elements can refine crystal grains, improve the microstructure of the target material, improve the density and strength of the target material and adjust the electrical properties of the target material, normal pressure sintering is adopted, the pressure sintering equipment is simple, the cost is low, and large-scale production is easy to realize; low-temperature sintering is adopted, decomposition of MoO3 can be effectively inhibited, excessive oxygen vacancies are prevented from being generated in the target material, and therefore the stoichiometric ratio and the electrical property of the target material are guaranteed; sintering is carried out in the air or nitrogen atmosphere, excessive oxidation or reduction of MoO3 can be avoided, and it is guaranteed that components of the target material are stable.

Description

Technical Field

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

[0002] With the rapid development of display technology, display panels have higher and higher requirements for BM materials. BM materials are mainly used for shading and preventing light leakage, and their performance directly affects the contrast, brightness and color performance of display panels. At present, BM materials mainly use the following materials:

[0003] Metal chromium (Cr) film: Traditional BM material, with good light-shielding performance, but its reflectivity is high, which can easily cause light pollution and affect the display effect.

[0004] Carbon-based materials: such as graphene and carbon nanotubes, have excellent conductivity and light absorption properties, but are expensive, complex processes, and difficult to apply on a large scale.

[0005] Metal oxides, such as molybdenum oxide (MoO3) and titanium oxide (TiO2), have received extensive attention in recent years. Among them, molybdenum oxide thin films have gradually become an ideal choice for BM materials due to their excellent properties such as low reflectivity, high absorptivity, and high resistivity.

[0006] However, the reasonable formula and ratio of the existing molybdenum oxide target is the key to the performance of the target. Since it is used for BM materials, the target needs to have low reflectivity, high absorption rate and high resistance. In addition, the preparation method of molybdenum oxide target mainly has the following problems: high equipment cost: spark plasma sintering (SPS) and vacuum sintering equipment are expensive, which increases the production cost; complex process: sintering needs to be carried out under vacuum or special atmosphere, the operation is complicated and difficult to control; it is difficult to achieve large-scale production: the equipment production capacity is limited and it is difficult to meet the needs of large-scale production. Summary of the invention

[0007] In view of this, the purpose of the present invention is to provide a molybdenum oxide-based target material for BM materials in the display field and a preparation method thereof, so as to solve the problems arising in the background technology.

[0008] Based on the above purpose, the present invention provides a molybdenum oxide-based target material for BM materials in the display field, comprising the following components in mass percentage: MoO3: 75-85%, MoO2: 8-12%, Mo: 8-12%, and rare earth elements: 0.3-0.7%.

[0009] Preferably, the rare earth element is selected from one or more of yttrium, cerium and lanthanum.

[0010] Preferably, the rare earth elements yttrium, cerium and lanthanum are added in the form of oxides.

[0011] A method for preparing a molybdenum oxide-based target material for BM materials in the display field comprises the following steps:

[0012] Step 1, weighing high-purity MoO3, MoO2, and Mo powders according to mass percentage, adding one powder of Y2O3, CeO2, and La2O3, placing the weighed raw materials in a ball mill, and wet grinding with ethanol as a medium;

[0013] Step 2, drying the wet-milled powder, and then sieving it under a 200-mesh sieve to obtain a powder with uniform particle size;

[0014] Step 3, placing the treated powder in a stainless steel mold and cold pressing it under normal pressure to obtain a green body;

[0015] Step 4, placing the green body in a high temperature sintering furnace and sintering at normal pressure in air or nitrogen atmosphere;

[0016] Step five: cutting and grinding the sintered target material to achieve the required size and shape accuracy.

[0017] Step six, conducting resistivity testing, density testing and bending strength testing on the prepared molybdenum oxide-based target material.

[0018] Preferably, the grinding balls used in the wet grinding in step 1 are zirconia balls, the ball-to-material ratio is 5:1, and the grinding time is 6-8 hours.

[0019] Preferably, the cold pressing molding pressure in step three is 100-200 MPa, and the holding time is 5-10 minutes.

[0020] Preferably, in step 4, the sintering heating rate is 5-10°C / min, the sintering temperature is 600-800°C, and the holding time is 2-4 hours.

[0021] Preferably, in step six, the resistivity is measured by a four-probe method, the density is measured by an Archimedes drainage method, and the bending strength is measured by a three-point bending method.

[0022] Beneficial effects of the present invention: MoO3 of the present invention is used as a main component to provide the basic structure and function of the target material; the introduction of MoO2 can improve the conductivity of the target material, reduce the resistivity, and improve the density of the target material; the addition of metal molybdenum can further improve the conductivity and mechanical strength of the target material; doping with rare earth elements can refine the grains, improve the microstructure of the target material, improve the density and strength of the target material, and at the same time adjust the electrical properties of the target material.

[0023] The present invention adopts atmospheric pressure sintering. Compared with SPS and vacuum sintering, atmospheric pressure sintering equipment is simple, cost-effective, and easy to achieve large-scale production; the present invention adopts low-temperature sintering, using a relatively low sintering temperature of 600-800°C, which can effectively inhibit the decomposition of MoO3 and avoid the generation of excessive oxygen vacancies in the target material, thereby ensuring the stoichiometric ratio and electrical properties of the target material; the present invention performs sintering in an air or nitrogen atmosphere, which can avoid excessive oxidation or reduction of MoO3 and ensure the stability of the composition of the target material. DETAILED DESCRIPTION

[0024] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0025] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0026] Example 1

[0027] A molybdenum oxide-based target material used for BM materials in the display field comprises the following components in percentage by mass: MoO3 80%, MoO2 10%, Mo 10%, and doped Y2O3 0.5%.

[0028] Example 2

[0029] A molybdenum oxide-based target material used for BM materials in the display field comprises the following components in percentage by mass: MoO3 75%, MoO2 15%, Mo 10%, and doped CeO2 0.5%.

[0030] Example 3

[0031] A molybdenum oxide-based target material used for BM materials in the display field comprises the following components in percentage by mass: MoO3 85%, MoO25%, Mo 10%, and La2O3 0.5%.

[0032] Comparative Example 1

[0033] Raw material composition: MoO3 100%, does not contain MoO2, Mo and rare earth elements.

[0034] Comparative Example 2

[0035] Raw material composition: MoO3 70%, MoO2 20%, Mo 10%, and no rare earth elements.

[0036] Comparative Example 3

[0037] Raw material composition: MoO3 80%, MoO2 10%, Mo 10%, Y2O3 1.0%. The rare earth element content of this embodiment is higher than that of the embodiment.

[0038] Examples 1-3 and Comparative Examples 1-3 use the following preparation methods to prepare the target materials:

[0039] S1, weighing raw materials according to mass percentage, placing the weighed raw materials in a ball mill, and wet grinding them with ethanol as the medium, the grinding balls for wet grinding are zirconia balls, the ball-to-material ratio is 5:1, and the grinding time is 7 hours;

[0040] S2, drying the wet-milled powder, and then sieving it under a 200-mesh sieve to obtain a powder with uniform particle size;

[0041] S3, placing the treated powder in a stainless steel mold, and cold pressing the powder under normal pressure, wherein the cold pressing pressure is 150 MPa, and the holding time is 8 minutes, to obtain a green body;

[0042] S4, placing the green body in a high-temperature sintering furnace, sintering at normal pressure in air or nitrogen atmosphere, with a sintering heating rate of 7°C / min, a sintering temperature of 600-800°C, and a holding time of 3 hours;

[0043] S5, cutting and grinding the sintered target material to achieve the required size and shape accuracy.

[0044] S6, resistivity test, density test and bending strength test are performed on the prepared molybdenum oxide-based target material. The resistivity is measured by a four-probe method, the density is measured by an Archimedes drainage method, and the bending strength is measured by a three-point bending method.

[0045] Example 1 Target material measured: resistivity: 9×10 -5 Ω·cm, density: 9.2g / cm 3 , flexural strength: 160MPa.

[0046] Example 2 Target material measured: resistivity: 8×10 -5 Ω·cm, density: 9.1g / cm 3 , flexural strength: 155MPa.

[0047] Example 3 Target material measured: resistivity: 1×10 -4 Ω·cm, density: 9.0g / cm 3 , flexural strength: 150MPa.

[0048] Comparative Example 1: Target material: resistivity: 2×10 -4 Ω·cm, density: 8.5g / cm3, flexural strength: 140MPa.

[0049] Comparative Example 2: Target material: resistivity: 1.5×10 -4 Ω·cm, density: 8.8g / cm 3 , flexural strength: 145MPa.

[0050] Comparative Example 3: Target material: resistivity: 1.2×10 -4 Ω·cm, density: 9.0g / cm 3 , flexural strength: 148MPa.

[0051] It can be seen from the above test results that the embodiment has low resistivity, high density and good bending strength, while the density of comparative example 3 after doping with more rare earth elements is not much different from that of the embodiment, but the resistivity and bending strength are not as good as those of the embodiment.

[0052] It should be understood by those skilled in the art that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the present invention is limited to these examples; under the concept of the present invention, the technical features in the above embodiments or different embodiments may also be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity. Any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A molybdenum oxide-based target material for BM materials in the display field, characterized in that: The invention comprises the following components in mass percentage: MoO3: 75-85%, MoO2: 8-12%, Mo: 8-12%, and rare earth element: 0.3-0.7%.

2. The molybdenum oxide-based target material for BM materials in the display field according to claim 1, characterized in that: The rare earth element is selected from one or more of yttrium, cerium and lanthanum.

3. The molybdenum oxide-based target material for BM materials in the display field according to claim 2, characterized in that: The rare earth elements yttrium, cerium and lanthanum are added in the form of oxides.

4. The method for preparing a molybdenum oxide-based target material for BM materials in the display field according to claim 3, characterized in that: The following steps are included: Step 1, weighing high-purity MoO3, MoO2, and Mo powders according to mass percentage, adding one powder of Y2O3, CeO2, and La2O3, placing the weighed raw materials in a ball mill, and wet grinding with ethanol as a medium; Step 2, drying the wet-milled powder, and then sieving it under a 200-mesh sieve to obtain a powder with uniform particle size; Step 3, placing the treated powder in a stainless steel mold and cold pressing it under normal pressure to obtain a green body; Step 4, placing the green body in a high temperature sintering furnace and sintering at normal pressure in air or nitrogen atmosphere; Step five: cutting and grinding the sintered target material to achieve the required size and shape accuracy. Step six, conducting resistivity testing, density testing and bending strength testing on the prepared molybdenum oxide-based target material.

5. The method for preparing a molybdenum oxide-based target material for BM materials in the display field according to claim 4, characterized in that: The grinding balls used in the wet grinding in step 1 are zirconia balls, the ball-to-material ratio is 5:1, and the grinding time is 6-8 hours.

6. The method for preparing a molybdenum oxide-based target material for BM materials in the display field according to claim 4, characterized in that: The cold pressing molding pressure in step three is 100-200 MPa, and the holding time is 5-10 minutes.

7. The method for preparing a molybdenum oxide-based target material for BM materials in the display field according to claim 4, characterized in that: In the step 4, the sintering heating rate is 5-10°C / minute, the sintering temperature is 600-800°C, and the heat preservation time is 2-4 hours.

8. The method for preparing a molybdenum oxide-based target material for BM materials in the display field according to claim 4, characterized in that: In step six, the resistivity is measured by a four-probe method, the density is measured by an Archimedes drainage method, and the bending strength is measured by a three-point bending method.