KR20220081691A - Tungsten oxide sintered body, sputtering target and oxide thin film - Google Patents

Abstract

The present invention provides a tungsten oxide sintered body, a sputtering target including the sintered body, and an oxide thin film formed therefrom.
In the present invention, by adding a specific (semi)metal oxide to the non-sintering tungsten oxide in a predetermined range, it is possible to simultaneously secure improved sinterability and high density characteristics even when sintering without pressure is performed.

Description

Tungsten oxide sintered body, sputtering target and oxide thin film

The present invention relates to a tungsten oxide sintered body, a sputtering target including the sintered body, and an oxide thin film formed therefrom. The present invention relates to a tungsten oxide-based oxide sintered compact with improved sinterability and density characteristics, a sputtering target, and an oxide thin film formed therefrom.

In recent years, the use of a material with a lower electrical resistance value as an electrode material or a wiring material is made|formed with high integration of LSI. Among them, high-purity tungsten, which has a low resistance value and is thermally and chemically stable, is used as an electrode material or a wiring material.

These electrode materials and wiring materials are generally manufactured by sputtering and CVD. The sputtering method is more widely used than the CVD method in that the structure and operation of the apparatus are relatively simple, can be easily formed, and is low cost. At this time, the tungsten target used when forming an electrode material or a wiring material into a film by the sputtering method is required to have high purity and high density. As a conventional method of manufacturing a tungsten-based target, a method of manufacturing an ingot using electron beam melting and then hot rolling it, a method of pressing and sintering tungsten powder and then rolling, and/or a CVD method on one surface of a tungsten bottom plate A so-called CVD-W method of laminating a tungsten layer is known.

On the other hand, as shown in the tungsten-oxygen (W-O) phase diagram of FIG. 1, in the case of tungsten oxide (WOx), not only a lot of intermediate phases exist but also oxygen deficiency is severe, so that sintering itself is difficult. (難燒結) is a substance. When using a tungsten oxide-based ceramic material that is difficult to sinter and has a low density, it is difficult to construct a high-density (eg, relative density of 90% or more) target, and when sputtering is performed using the manufactured target, back depo. And foreign matter is generated due to the generation of nodules, etc., which inevitably causes deterioration of the physical properties of the thin film.

The present invention has been devised to solve the above problems, and by adding a specific element to a non-sinterable tungsten oxide, which is a main raw material, in a predetermined range, a novel tungsten oxide sintered body capable of improving sinterability and ensuring high density, the sintered body It is a technical task to provide a sputtering target comprising and an oxide thin film formed therefrom.

Other objects and advantages of the present invention may be more clearly explained by the following detailed description and claims.

In order to achieve the above technical problem, the present invention is tungsten; And Co, Al, Y, and at least one element (A) selected from the group consisting of Si; provides a tungsten oxide sintered body containing.

In one embodiment of the present invention, an atomic ratio of tungsten and at least one element (A) present in the oxide sintered body may be 0.9 to 0.99: 0.1 to 0.01.

For one embodiment of the present invention, the relative density of the sintered body may exceed 90%.

For one embodiment of the present invention, based on the total atomic weight present in the sintered body, the atomic weight of tungsten may be 90 to 99.0 atomic%, and the atomic weight of at least one element (A) may be 0.1 to 10 atomic% .

For one embodiment of the present invention, the oxide sintered body includes a (semi)metal oxide containing at least one element (A) selected from the group consisting of tungsten oxide and Co, Al, Y and Si, The (semi)metal oxide (A) containing the at least one element may be included in an amount of 1.0 to 7.0 wt% based on the total weight of the sintered body.

For one embodiment of the present invention, the (semi) metal oxide may include at least one selected from the group consisting of Co ₃ O ₄ , Al ₂ O ₃ , Y ₂ O ₃ , and SiO ₂ .

For one embodiment of the present invention, the oxide sintered body, tungsten oxide; And at least one (semi) metal oxide may be mixed and molded, and then produced by sintering without pressure.

In addition, the present invention provides a sputtering target comprising the above-described tungsten oxide sintered body.

In addition, the present invention provides an oxide thin film formed from the sputtering target described above.

According to an embodiment of the present invention, the sinterability of the tungsten oxide sintered body can be improved and high density can be secured by adding a (semi)metal oxide containing a specific element to the non-sinterable tungsten oxide in a predetermined range.

Accordingly, the tungsten oxide sintered body and sputtering target according to the present invention can be usefully applied to the formation of electrodes or wirings used in TFT structures of LCDs and OLEDs.

Effects according to the present invention are not limited by the contents exemplified above, and more various effects are included in the present specification.

1 is a phase diagram of tungsten-oxygen (WO).
Figure 2 is a graph of the relative density of the molded article prepared in Examples 1 to 4.
3 is a graph showing the relative density of the oxide sintered body prepared in Comparative Examples 1 to 3;
4 is a graph for evaluating shrinkage between the molded body and the oxide sintered body prepared in Examples 1 to 4;
5 is a graph showing the evaluation of shrinkage between the molded body and the oxide sintered body prepared in Comparative Examples 1 to 3;

Hereinafter, the present invention will be described in detail.

All terms (including technical and scientific terms) used in this specification may be used with meanings commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in a commonly used dictionary are not to be interpreted ideally or excessively unless clearly defined in particular.

In addition, throughout the specification, when a part "includes" a certain component, it means that other components may be further included, rather than excluding other components, unless specifically stated to the contrary. In addition, throughout the specification, "on" or "on" means that it includes not only the case located above or below the target part, but also the case where there is another part in the middle, and the direction of gravity must be It does not mean that it is positioned above the reference. And, in the present specification, terms such as “first” and “second” do not indicate any order or importance, but are used to distinguish components from each other.

The present invention relates to a high-density sintered body and a sputtering target based on tungsten oxide (WO ₃ ), which is a non-sintering material, and more specifically, to a pressure-free sintering method by using a small amount of a specific dopant that aids in the sinterability of tungsten oxide. An object of the present invention is to provide a sintered body and a sputtering target that can simultaneously improve sinterability and secure high density.

As shown in FIG. 1 below, conventional tungsten oxide (WOx) is a non-sintering material that is difficult to sinter because there are many intermediate phases and the like as well as oxygen deficiency is severe. In the case of sintering without pressurization using such tungsten oxide (WO ₃ ), there is a limit to the increase of the sintering density, and when the temperature is raised, the amount of volatilization increases and the density decreases rather. That is, heat is required as a driving force during sintering. In general, the higher the heat, the more advantageous in securing sinterability (densification), but in the case of some raw materials, problems such as volatilization occur and the density is lowered. In order to suppress the above-mentioned phenomenon, the sinterability can be partially improved by applying pressure at a relatively low temperature using a hot press (HP) or a hot isostatic press (HIP). Therefore, it is not suitable in terms of mass production, and there is a limit in increasing the size of the sintered body in the manufacturing process that applies a high pressure.

Accordingly, in the present invention, by adding a specific dopant that aids in the sinterability of tungsten oxide in a predetermined range, it is possible to improve the sintering density according to the temperature drop effect even when sintering without pressure is performed. In particular, the tungsten oxide sintered compact sintered without pressure according to the present invention can secure equivalent density characteristics and resistivity characteristics compared to the oxide sintered compact that has undergone conventional pressure sintering (eg, HP, HIP, etc.). And, compared to the pressure-sintered oxide sintered body, it is very excellent in terms of enlargement and mass production of the sintered body, and has the advantage of low equipment cost.

In addition, when there is no added element, the density of the tungsten oxide target is very low, and the specific resistance is high. As such, when the resistance of the target is high, there is a problem in that plasma is not formed during DC sputtering. In contrast, the tungsten oxide target according to the present invention can provide a high-density sintered target at a level capable of sputtering even by pressureless sintering by securing sinterability by adding a dopant.

<Oxide Sintered Body>

The oxide sintered body according to an embodiment of the present invention is for manufacturing a sputtering target having a tungsten oxide (WO _X ) as a main component, and heat treatment of raw material powder of a metal (eg, W) or ceramic (eg, WO ₃ ) to make it into one lump.

For example, the oxide sintered body may include tungsten; and at least one element (A) selected from the group consisting of Co, Al, Y and Si; 0.1~0.01 is satisfied.

At this time, at least one element (A) or a compound containing the element (A) (eg, a (semi) metal oxide) is a dopant ( acts as a dopant).

In the oxide sintered body according to the present invention, since the atomic ratio of tungsten (W) atoms and at least one (semi) metal atom satisfies the above-mentioned values, sinterability improvement and density improvement according to the addition of a small amount of sintering aid (dopant) can be promoted Accordingly, a high-density sputtering target can be manufactured using tungsten oxide (WO ₃ ), which is a difficult-to-sinter material, even if the conventional pressure sintering by applying a high pressure is not performed.

In the sintered compact containing the (semi)metal oxide containing at least one element as described above, based on the total atomic weight present in the sintered compact, the atomic weight of tungsten is 90 to 99.0 atomic%, and at least one element ( The atomic weight of A) may be 0.1 to 10 atomic%. For a specific example of the at least one element (A), the atomic weight of cobalt (Co) may be 0.5 to 1.5 atomic%, and the atomic weight of aluminum (Al) may be 0.01 to 0.1 atomic%. In addition, the atomic weight of yttrium (Y) may be 0.01 to 0.3 atomic%, and the atomic weight of silicon (Si) may be 0.01 to 0.1 atomic%.

Here, tungsten and at least one element (A) contained in the oxide sintered body are not particularly limited, as long as they satisfy the above-mentioned atomic ratio values. For example, tungsten and at least one element (A) may each be included alone as a metal component, or include all conventional compound forms known in the art containing the element. Preferably, it may be tungsten or an oxide each containing at least one element (A).

More specifically, the oxide sintered body according to the present invention is composed of tungsten oxide (WO ₃ ) as a base material, and by additionally adding at least one specific element, specifically tungsten oxide, and Co, Al, Y and Si and a (semi)metal oxide containing at least one element (A) selected from the group consisting of.

The (semi) metal oxide is not particularly limited as long as it is in the form of an oxide containing at least one element (A), for example, Co ₃ O ₄ , Al ₂ O ₃ , Y ₂ O ₃ , and SiO ₂ From the group consisting of It may include one or more selected types.

Based on the weight of the input (semi) metal oxide, the (semi) metal oxide (A) containing at least one element is 1.0 to 7.0 weight based on the total weight (eg, 100 wt %) of the sintered body % may be included. As a specific example of the (semi) metal oxide, the amount of cobalt oxide (Co ₃ O ₄ ) may be 2 to 5 wt%, and the amount of aluminum oxide (Al ₂ O ₃ ) may be 0.5 to 3 wt%. have. In addition, the amount of yttrium oxide (Y ₂ O ₃ ) may be 2 to 7 wt%, and the amount of silicon oxide (SiO ₂ ) added may be 0.5 to 3 wt%. In addition, the content of tungsten oxide may be the remaining amount excluding the aforementioned (semi) metal oxide, for example, may be 93 to 99.0 wt%, specifically, may be 95 to 99.0 wt%.

The tungsten oxide sintered body according to the present invention configured as described above may have a relative density of more than 90%, and the upper limit thereof is not particularly limited. In addition, the size of the crystal grains included in the sintered body is not particularly limited, and may be, for example, 1 to 20 μm, specifically 1 to 10 μm.

In addition, the sputtering target according to another embodiment of the present invention, the above-described tungsten oxide sintered body; and a backing plate joined to one surface of the sintered body to support the sintered body.

Here, the backing plate is a substrate for supporting the sintered body for the sputtering target, and a conventional backing plate known in the art may be used without limitation. At this time, the material constituting the backing plate and the shape thereof are not particularly limited.

<Method for manufacturing oxide sintered compact and sputtering target>

Hereinafter, a method for manufacturing an oxide sintered body according to an embodiment of the present invention will be described. However, it is not limited only by the following manufacturing method, and the steps of each process may be modified or selectively mixed as needed.

For a preferred embodiment of the manufacturing method, (i) raw material powder comprising tungsten oxide and a (semi)metal oxide containing at least one element (A) selected from the group consisting of Co, Al, Y and Si preparing ('S10 step'); (ii) manufacturing a molded body using the raw material powder ('S20 step'); and (iii) sintering the molded body at 900 to 1200° C. for 0.5 to 3 hours without pressure to prepare a sintered body ('S30 step'); may be configured to include.

Hereinafter, the manufacturing method is divided into each process step and described as follows.

(i) Preparation of raw material powder ('Step S10')

In the step S10, as a step of preparing a raw material powder including tungsten oxide, a (semi) metal oxide containing at least one element (A), specifically, a tungsten oxide powder, Co ₃ O ₄ , Al ₂ O ₃ , Y ₂ O ₃ , and SiO ₂ After weighing one or more (semi)metal oxide powders selected from the group consisting of a target composition, each powder is put into a mixer, pulverized and mixed to prepare a mixture.

When mixing the above-mentioned raw powders, if necessary, conventional additives known in the art, such as binders, dispersants, antifoaming agents, etc. may be further included. In this case, the amount of the additive may be appropriately adjusted within a conventional range known in the art, and for example, 0.01 to 10% by weight relative to the total weight of the powder in the slurry (eg, 100% by weight) may be used.

The dispersant is added to satisfy the purpose of finely pulverizing the pulverized raw material particles while maintaining an even and stable dispersion of the pulverized raw material particles in a solution for a long time. Non-limiting examples of the dispersing agent that can be used include an organic acid series with a carboxyl group, such as citric acid, polyacrylic acid (PAA) or a salt, copolymer, or a combination thereof.

In addition, the binder is added to maintain the molding strength of the molded body during the molding process after drying the slurry into powder. Non-limiting examples thereof include polymers such as polyvinyl alcohol and polyethylene glycol.

The antifoaming agent is to remove the foam in the slurry, and silicone oil, octyl alcohol, boric acid, and the like can be used in general.

Mixing and pulverizing of the raw material powder is not particularly limited, and may be performed using a conventional ball mill, an attraction mill, a bead mill, etc. known in the art. At this time, grinding and mixing conditions are not particularly limited, and for example, the speed of the ball mill may be about 150 to 300 rpm, and the mixing time may be 8 to 15 hours.

As a specific example of step S10, in order to proceed with mixing and pulverizing the raw material powder through a wet ball mill, a pre-measured element powder is put in using a prepared PE barrel, and about 2 to 4 times the raw material, preferably Three times the weight of zirconia balls is added, and then, distilled water or pure water is added at an approximate level of 1.5 times the raw material to perform ball milling.

Thereafter, the wet-pulverized mixture is dried in a dry oven, and a ball mill is performed again to obtain a dried raw material powder. In this case, the drying conditions are not particularly limited, and for example, drying may be carried out in a dry oven at about 90 to 110° C. for about 10 to 15 hours.

Then, the dried mixture is again ball milled to obtain a dry raw material powder. If necessary, the zirconia balls and powder are separated by filtering through a mesh of about 90 to 110 mesh, specifically 100 mesh.

(ii) Formed body manufacturing ('S20 step')

The step S0 is a step of manufacturing a molded body from the prepared raw material powder. More specifically, the raw material powder is put into a molding machine and molded through a process to manufacture a molded body of a predetermined standard.

In order to increase the density of the molded body, the molding process may be performed in two steps. For example, the primary molding process may use a uniaxial molding machine, and the secondary molding process may use an isostatic molding machine.

Conditions in the primary and secondary molding processes are not particularly limited, and may be appropriately adjusted within common conditions known in the art. For example, the pressure at the time of primary molding after inputting the raw material powder into the uniaxial molding machine is not particularly limited, and may specifically be 10 MPa or more per unit area. In addition, after the primary molded article is put into the isostatic pressure molding machine, the pressure during secondary molding is not particularly limited, and may be, for example, 2000 MPa or more per unit area, preferably in the range of 2000 to 3000 MPa.

To give a specific example of the step S20, a primary molded body is manufactured using an STS material mold having a size of 20 Φ according to the determined weight of the powder. At this time, the pressure may be conducted under the minimum pressure conditions constituting the shape, for example, about 10 Mpa, and the time may proceed at a maintenance level of 1 minute. Thereafter, the secondary molding was carried out using hydrostatic pressure molding (CIP), and the holding time was carried out for several hours under 200 Mpa conditions. At this time, since the second hydrostatic pressure proceeds with an organic solvent including water, it can be carried out while being put in an acrylic-based sealing material (eg, an envelope).

(iii) sintered body manufacturing ('S30 step')

In step S30, the produced compact is sintered under predetermined conditions to prepare a sintered compact.

At this time, the sintering conditions are not particularly limited, and may be appropriately adjusted within common conditions known in the art. For example, it may be sintered without pressure at 900 to 1200 ℃ for 0.5 to 3 hours. The sintering may be performed under an oxygen atmosphere or under an inert condition.

To give a specific example of the step S30, the prepared molded body is put into an alumina crucible of a certain standard and sintering is performed. In this experiment, it was conducted in a nitrogen atmosphere for the purpose of improving electrical conductivity due to the lack of some oxygen in tungsten oxide. In order to confirm the difference in characteristics between the molded body before heat treatment and the sintered body after heat treatment, the weight, diameter, and height of the green body and the sintered body were measured (see Table 1 and FIGS. 1 to 4 below).

The sintered compact manufactured through this process has a relative density exceeding 90%, and the upper limit thereof is not particularly limited.

(iv) sputtering target manufacturing

Thereafter, a commercialized sputtering target is manufactured through diffusion bonding and final processing known in the art.

Specifically, after bonding the sintered compact obtained in step S30 with a backing plate to secure a bonding rate of 99.5% or more, processing is performed to the final desired thickness using processing equipment, and a bead is placed on the backing plate surface And/or it is possible to obtain a final sputtering target by performing an arc spray (Arc spray) treatment.

<Oxide thin film>

The present invention provides an oxide thin film deposited using the aforementioned tungsten oxide target.

Although differences in components may occur depending on the deposition atmosphere, the oxide thin film is prepared by sputtering the above-described tungsten oxide target, and thus has substantially the same composition as the target. Accordingly, an oxide thin film having high density characteristics exceeding 90% relative density and excellent resistivity characteristics may be formed.

In one embodiment, the oxide thin film is tungsten; and at least one element (A) selected from the group consisting of Co, Al, Y and Si; : It can be 0.1~0.01.

The oxide thin film formed using the tungsten oxide target may be in an amorphous form or a crystalline form. The amorphous oxide thin film may be crystallized by performing heat treatment at a temperature in the range of 200 to 350° C. after forming the film.

The transparent conductive thin film according to the present invention may be manufactured using a conventional sputtering method known in the art. For one embodiment of the manufacturing method, after mounting the above-described tungsten oxide sintered body sputtering target, it includes the step of depositing at room temperature in an oxygen and/or argon atmosphere in a vacuum chamber.

As the substrate and sputtering apparatus used, conventional ones known in the art may be used without limitation. Specifically, it can be formed while supplying oxygen or oxygen and high-purity argon gas in a vacuum chamber at a rate of 80 to 110 sccm (standard cubic centimeters per minute), specifically, supplying at a rate of 95 to 105 sccm, to form a film It can be deposited at room temperature (RT) without applying a temperature to the substrate.

The oxide thin film obtained as described above can be used in various ways when manufacturing a semiconductor device, and for example, it can be applied to form a wiring or an electrode when manufacturing a semiconductor. In particular, it can be usefully used as a barrier layer of an electrode when manufacturing a thin film transistor. Specifically, when the thin film of the present invention is used for the barrier layers of the source and drain electrodes included in the thin film transistor, the contact resistance can be lowered, and the properties of the thin film transistor can be improved by having excellent transparency and a low refractive index.

Since the above-described tungsten oxide-based sputtering target according to the present invention and an oxide thin film formed therefrom have high density and excellent resistivity, the TFT structure of LCD and OLED or the electron injection layer and the connection resistance of the organic electroluminescent device are low. can do. Accordingly, the above-mentioned oxide thin film may include various display devices such as a liquid crystal display device or an organic electroluminescent display device, an information delivery device such as a flat panel display such as LCD, PDP, OLED, and LED; Surface light source lighting device touch panel such as OLED and LED; and/or may be applied without limitation to an information delivery device using the same.

Hereinafter, the present invention will be described in detail through examples. However, the following examples only illustrate the present invention, and the present invention is not limited by the following examples.

[Example 1] Preparation of W-Co-based sintered compact

Metals W and Co were mixed and molded in a ratio of 0.9: 0.1 based on molar mass, and WO ₃ : Co ₃ O ₄ was mixed in a ratio of 96.3: 3.7 based on the weight ratio of the input oxide to prepare a molded body. Thereafter, a sintered body was manufactured by heat treatment at about 970 to 1200° C. for 2 hours under a nitrogen atmosphere using a heat treatment facility.

[Example 2] Preparation of W-Al-based sintered body

Metal W and Al were mixed and molded in a ratio of 0.95:0.05 based on molar mass, and WO ₃ : Al ₂ O ₃ was mixed in a ratio of 98.8:1.2 based on the weight ratio of the input oxide to prepare a molded body. Thereafter, a sintered body was fabricated by heat treatment at about 970 to 1200° C. for 2 hours in a nitrogen atmosphere using a heat treatment facility.

[Example 3] Preparation of W-Y-based sintered compact

Metals W and Y were mixed and molded in a ratio of 0.9: 0.1 based on molar mass, and WO ₃ : Y ₂ O ₃ was mixed in a ratio of 95.0: 5.0 based on the weight ratio of the input oxide to prepare a molded body. Thereafter, a sintered body was fabricated by heat treatment at about 970 to 1200° C. for 2 hours in a nitrogen atmosphere using a heat treatment facility.

[Example 4] Preparation of W-Si-based sintered body

Metal W and Si were mixed and molded at a ratio of 0.95: 0.05 based on molar mass, and WO ₃ : SiO ₂ was mixed at a ratio of 98.6: 1.4 based on the weight ratio of the input oxide to prepare a molded body. Thereafter, a sintered body was fabricated by heat treatment at about 970 to 1200° C. for 2 hours in a nitrogen atmosphere using a heat treatment facility.

[Comparative Example 1] Preparation of W-based sintered compact

A sintered body was manufactured in the same manner as in Example 1, except that WO ₃ powder was used alone without using a dopant.

[Comparative Example 2] Preparation of W-Ta-based sintered compact

Metal W and Ta were mixed and molded in a ratio of 0.9: 0.1 based on molar mass, and WO ₃ : Ta ₂ O ₅ was mixed in a ratio of 90.4: 9.6 based on the weight ratio of the input oxide to prepare a molded body. Thereafter, a sintered body was manufactured by heat treatment at about 970 to 1200° C. for 2 hours under a nitrogen atmosphere using a heat treatment facility.

[Comparative Example 3] Preparation of Mo-Co-based sintered compact

Metal Mo and Co were mixed and molded in a ratio of 0.97: 0.03 based on molar mass, and MoO _x : Co ₃ O ₄ was mixed in a ratio of 98: 2 based on the weight ratio of the input oxide to prepare a molded body. Thereafter, a sintered body was manufactured by heat treatment at about 900 to 1050° C. for 2 hours in a nitrogen atmosphere using a heat treatment facility.

At this time, in the case of the sintered body of Comparative Example 3 in which Mo was added, heat treatment was performed at a relatively low temperature compared to the sintered body of the example in which WO ₃ was added in consideration of the volatilization and melting of MoO _x .

[Experimental Example 1] Evaluation of physical properties of a molded article

The physical properties of each molded article prepared in Examples 1 to 4 and Comparative Examples 1 to 3 were evaluated as follows.

Specifically, for each molded article, the diameter (D) and height (T) were measured using a vernier caliper, and the weight (Mass) was measured using a scale. In addition, the relative density was converted into a percentage by converting the input amount of each weight into a volume %, and the level compared to the theoretical density was converted into a percentage, and the results are shown in Table 1 below. At this time, the density of the measured sample was calculated as weight/volume.

D (mm) T (mm) Mass (g) Relative density (%) Example 1 19.52 6.26 7.9225 59.5 Example 2 19.55 6.41 7.9208 58.1 Example 3 19.52 6.31 7.8758 59.6 Example 4 19.71 6.31 7.8893 58.6 Comparative Example 1 19.82 5.85 7.8638 60.9 Comparative Example 2 19.37 6.21 7.8835 59.5 Comparative Example 3 19.54 6.48 7.9100 66.0

[Experimental Example 2] Evaluation of density and shrinkage of sintered compact

After heat treatment was performed on each of the samples prepared in Examples 1 to 4 and Comparative Examples 1 to 3, changes in physical properties of each sintered body were measured.

The evaluation of the physical properties of the sintered body after the heat treatment was measured in the same manner as in Experimental Example 1 described above. As an example, the results of the relative density calculated by measuring the diameter, height and weight of the sintered body are shown in FIGS. 2 and 3 below.

As a result of the experiment, in Examples 1 to 4, it was found that the relative density also significantly increased as the sintering temperature was increased from 950°C to 1150°C (see FIG. 2 ). On the other hand, in the case of Comparative Examples 1 to 3, it was found that as sintering progressed, the relative density of the compact was lowered than that of the molded body (see FIG. 3 ).

In addition, the shrinkage was calculated by measuring the diameter and height of the molded body before heat treatment and the sintered body after heat treatment, and the results are shown in FIGS. 4 and 5 below.

[Experimental Example 3] Evaluation of specific resistance of sintered compact

Specific resistance characteristics were evaluated for each sintered body sample prepared in Examples 1 to 4 and Comparative Examples 1 to 3.

Specifically, as a sample of the sintered body, a sample having a relatively high relative density of 1150°C was used, and the specific resistance of the sample was measured using a Loresta-GX MCP-T700 product (Mitsubishi chemical). The results are shown in Table 2 below.

top view if Unit (Ωcm) Example 1 0.96 1.35 10^-1 Example 2 0.75 1.21 10^-1 Example 3 0.67 1.35 10^-1 Example 4 1.69 1.97 10^-1 Comparative Example 1 10.1 11.5 10^-1 Comparative Example 2 9.9 10.1 10^4 Comparative Example 3 4.5 7.5 10^1

Claims (9)

tungsten; and
At least one element (A) selected from the group consisting of Co, Al, Y and Si; A tungsten oxide sintered body comprising a. According to claim 1,
The atomic ratio of tungsten present in the oxide sintered body and at least one element (A) is 0.9 to 0.99: 0.1 to 0.01, tungsten oxide sintered body. According to claim 1,
A tungsten oxide sintered body with a relative density exceeding 90%. According to claim 1,
The oxide sintered body,
tungsten oxide, and
A (semi) metal oxide containing at least one element (A) selected from the group consisting of Co, Al, Y and Si,
The tungsten oxide sintered body containing the (semi)metal oxide (A) containing at least one element in an amount of 1.0 to 7.0 wt% based on the total weight of the sintered body. According to claim 1,
The (semi) metal oxide is a tungsten oxide sintered body comprising at least one selected from the group consisting of Co ₃ O ₄ , Al ₂ O ₃ , Y ₂ O ₃ , and SiO ₂ . 5. The method of claim 4,
The oxide sintered body is
tungsten oxide; and at least one (semi) metal oxide mixed and molded and then sintered without pressure, a tungsten oxide sintered body. The sputtering target containing the tungsten oxide sintered compact in any one of Claims 1-6. An oxide thin film formed from the sputtering target of claim 7. (i) preparing a raw material powder comprising tungsten oxide and a (semi) metal oxide containing at least one element (A) selected from the group consisting of Co, Al, Y and Si;
(ii) preparing a molded body using the raw material powder; and
(iii) preparing a sintered body by sintering the molded body at 900 to 1200° C. for 0.5 to 3 hours without pressure;
The method of claim 1 comprising a tungsten oxide sintered body.

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