JP2022105853A - Oxide sputtering target, and method of producing oxide sputtering target - Google Patents

Abstract

To provide an oxide sputtering target capable of stably producing a uniform oxide film with little variation in film resistance in the initial/intermediate/final stages of film deposition by sputtering, and a method of producing the oxide sputtering target.SOLUTION: The oxide sputtering target constituted of a sintered oxide comprising Zn as a metal component as a primary component, in which the coefficient of variation of the specific resistance value in the thickness direction is 0.20 or less. The method of producing an oxide sputtering target comprises: a calcination step S02 of calcining raw material powder to be sintered; a crushing step S03 of crushing the calcined raw material powder to be sintered; and a sintering step S04 of sintering the crushed calcined raw material powder to be sintered to obtain a sintered body. The degree of vacuum in the calcination step is in a range of 15 Pa or less, the calcination temperature is in a range of 600°C or more and 1000°C or less, and the retention time at the calcination temperature is 2 hours or more and 6 hours or less.SELECTED DRAWING: Figure 1

Description

The present invention relates to an oxide sputtering target made of an oxide sintered body containing Zn as a main component as a metal component, and a method for manufacturing the oxide sputtering target.

Conventionally, in an optical recording medium such as an optical disc, a protective film is formed in order to protect the recording layer and the light reflecting film.
In addition, patterned wiring films and electrodes are widely used in electronic devices such as touch panels, solar cells, and organic EL displays, and these wiring films and electrodes have a structure in which a protective film is laminated on a metal film. It is said that.

As the protective film described above, for example, as shown in Patent Documents 1 and 2, oxide films such as ITO film and ZnO film having excellent visible light transmittance are used.
Here, the above-mentioned oxide film is formed by a sputtering method using an oxide sputtering target. For example, Patent Documents 3 and 4 propose adding various elements to an oxide sputtering target in order to improve the characteristics of a ZnO film formed by a sputtering method.

Patent Document 3 describes an oxide sputtering target in which Ti and one or more selected from Ga or Al are added to ZnO. In this Patent Document 3, the content of Ga or Al is 0.03 or less as the atomic number ratio of (Ga + Al) / (Zn + Ti + Ga + Al), and the content of Ti is 0.05 to 0 as the atomic number ratio of Ti / (Zn + Ti + Ga + Al). It is said to be .25.

Patent Document 4 describes an oxide sputtering target in which Ti and Ga are added to ZnO. In Patent Document 4, the Ti and Ga contents are in the range of Ti 1.1 at% or more or Ga 4.5 at% or more, and the Ga content y (at%) is the Ti content x (at%). It is in the range of the value represented by (-2.5x + 9.8) or less and the range of the value represented by the titanium content x (at%) (-0.5x + 1.1) or more.

Japanese Unexamined Patent Publication No. 07-114841 Japanese Unexamined Patent Publication No. 2009-25576 Japanese Unexamined Patent Publication No. 2009-298649 Japanese Patent No. 4295811

By the way, in an oxide sputtering target made of an oxide sintered body containing Zn as a main component as a metal component, the characteristics of the formed oxide film vary depending on the initial / middle / final stage of the sputter film formation. In some cases, it was not possible to form an oxide film in a stable manner.

The present invention has been made in view of the above-mentioned circumstances, and is an oxide sputtering target capable of stably forming a uniform oxide film with little variation in characteristics at the initial / middle / final stage of sputtering deposition. An object of the present invention is to provide a method for producing the oxide sputtering target.

As a result of diligent studies by the present inventors in order to solve the above problems, the following findings were obtained. It was found that in an oxide sputtering target composed of an oxide sintered body containing Zn as a main component as a metal component, the surface layer portion is locally reduced during sintering, and the reduced state differs between the surface layer and the inside. .. Then, it was found that the specific resistance value in the target fluctuates depending on the difference in the reduction state.

The oxide sputtering target of the present invention is made based on the above-mentioned findings, and is composed of an oxide sintered body containing Zn as a main component as a metal component, and has a coefficient of variation of specific resistance value in the thickness direction. It is characterized by being 0.20 or less.

According to the oxide sputtering target having the above configuration, it is composed of an oxide sintered body containing Zn as a main component as a metal component, and the fluctuation coefficient of the specific resistance value in the thickness direction is suppressed to 0.20 or less. The reduction state does not differ significantly between the surface layer, which is the sputtered surface of the target, and the inside, and even when sputtering progresses, it is possible to suppress variations in the film resistance of the deposited oxide film. , It becomes possible to stably form a uniform oxide film.

Here, in the oxide sputtering target of the present invention, Ga is 10.0 atomic% or more and 20.0 atomic% or less, and Ti is 0.5 atomic% or more and 5.0 atoms, where the total of the metal components is 100 atomic%. % Or less, preferably composed of an oxide contained in a ratio of Zn and an unavoidable impurity metal element in the balance.
In this case, since it is composed of an oxide having the above-mentioned composition, an oxide film can be stably formed by a normal sputtering method such as a DC (direct current) sputtering method. Further, when a laminated film with a metal is produced, a laminated film having excellent environmental resistance can be obtained.

Further, in the oxide sputtering target of the present invention, further, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, B, Al, In, Si, Ge, Sn, At least one or two or more additive elements selected from the element group consisting of elements of the Pb, Sb, Bi and lanthanoid series are totaled, and the total of the metal components is 100 atomic%, which is 0.01 atomic% or more and 10.0 atoms. It is preferably contained in the range of% or less.
In this case, it is possible to form an oxide film having further improved environmental resistance and a lower resistance value.

Further, in the oxide sputtering target of the present invention, it is preferable that the oxide has a composite oxide and the abundance ratio of the composite oxide is 15% or more.
In this case, since the abundance ratio of the composite oxide is 15% or more, the oxide sintered body becomes dense, and cracks and cracks during sputtering can be more reliably suppressed.

The method for producing an oxide sputtering target of the present invention is a method for producing an oxide sputtering target for producing the above-mentioned oxide sputtering target, which is a temporary firing step of tentatively firing a sintered raw material powder and a calcined raw material. It includes a crushing step of crushing the powder and a sintering step of sintering the crushed sintered raw material powder to obtain a sintered body, and the degree of vacuum in the preliminary firing step is within the range of 15 Pa or less. It is characterized in that the firing temperature is within the range of 600 ° C. or higher and 1000 ° C. or lower, and the holding time at the firing temperature is within the range of 2 hours or more and 6 hours or less.

According to the method for manufacturing an oxide sputtering target having the above configuration, a calcination step of calcination raw material powder is provided, and the calcination conditions of the calcination step are defined as described above. The raw material powder can be reduced to a certain extent, and the local reduction reaction in the subsequent sintering step can be suppressed. As a result, the difference in the degree of reduction in the thickness direction becomes small, and the variation in the specific resistance value in the thickness direction can be suppressed.

Here, in the method for manufacturing an oxide sputtering target of the present invention, the degree of vacuum in the sintering step is within the range of 15 Pa or less, the sintering temperature is within the range of 900 ° C. or higher and 1100 ° C. or lower, and the sintering temperature is maintained. It is preferable that the time is within the range of 2 hours or more and 6 hours or less.
In this case, since the sintering conditions in the sintering step are defined as described above, the composite oxide can be sufficiently produced and a dense oxide sintered body can be obtained.

According to the present invention, an oxide sputtering target capable of stably forming a uniform oxide film with little variation in characteristics at the initial / middle / final stage of sputter film formation, and a method for manufacturing the oxide sputtering target are provided. Can be provided.

It is a flow figure which shows the manufacturing method of the oxide sputtering target which is this embodiment.

Hereinafter, an oxide sputtering target according to an embodiment of the present invention and a method for manufacturing the oxide sputtering target will be described.

The oxide sputtering target of the present embodiment is, for example, a protective film of an optical recording medium, a water vapor barrier film in various devices such as a liquid crystal display element, an organic EL element, and a solar cell, a touch panel, a solar cell, an organic EL display, and the like. It is used when forming an oxide film that serves as a wiring film and a protective film for electrodes in an electronic device.
This oxide film is required to have excellent visible light transmittance, and in the present embodiment, it is an oxide film containing Zn as a main component as a metal component.

The oxide sputtering target of the present embodiment is made of an oxide sintered body containing Zn as a main component as a metal component.
In the oxide sputtering target of the present embodiment, the coefficient of variation of the specific resistance value in the thickness direction is 0.20 or less, and the variation of the specific resistance value is suppressed to be small at least in the thickness direction of the sputtered surface. Has been done. Further, the coefficient of variation of the specific resistance value in the thickness direction is preferably 0.12 or less, and the coefficient of variation of the specific resistance value in the thickness direction is more preferably 0.10 or less.
In the present embodiment, the oxide sputtering target has a flat plate shape, the specific resistance value is measured at a plurality of points in the thickness direction thereof, and the average value and the standard deviation are changed by the following formula. The coefficient is calculated.
(Coefficient of variation) = (standard deviation) / (mean value)

Here, in the oxide sputtering target of the present embodiment, the total of the metal components is 100 atomic%, Ga is 10.0 atomic% or more and 20.0 atomic% or less, and Ti is 0.5 atomic% or more. It may be composed of an oxide containing 0 atomic% or less and the balance being Zn and an unavoidable impurity metal element.
In addition to Ga, Ti, and Zn, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, B, Al, In, Si, Ge, Sn, and Pb. , Sb, Bi and at least one or more additive elements selected from the element group consisting of elements of the lanthanoid series, 0.01 atomic% or more and 10.0 atomic% with the total metal component as 100 atomic%. It may be contained within the following range.

Further, in the oxide sputtering target of the present embodiment, it is preferable that the oxide has a composite oxide and the abundance ratio of the composite oxide is 15% or more. The upper limit of the abundance ratio of the composite oxide is preferably 50% or less. When the abundance ratio of the composite oxide in the oxide sputtering target is 15% or more, the coefficient of variation of the specific resistance value in the thickness direction is preferably 0.12 or less.
Here, as the composite oxide, for example, when Ga and Ti are contained in addition to Zn, ZnGa ₂ O ₄ , ZnTIO ₃ , Zn ₂ TIO ₄ , and the like can be mentioned.
The abundance ratio of the composite oxide can be calculated from the intensity of the main peak of each phase (single phase oxide, composite oxide) by X-ray diffraction measurement (XRD). For example, when Ga and Ti are contained in addition to Zn, the sum A of the peak intensities of the ZnO phase, Ga _{2O 3} phase, and TIO ₂ phase and the above-mentioned composite oxide (ZnGa ₂ O ₄ , ZnTIO ₃ and so on) From the total peak intensity B of Zn ₂ TiO ₄ etc.), the abundance ratio of the composite oxide is calculated by the following formula.
Absence ratio of composite oxide (%) = B / (A + B) × 100

Next, the method for manufacturing the oxide sputtering target according to the present embodiment will be described with reference to the flow chart of FIG.

(Sintered raw material powder forming step S01)
First, raw material powder such as zinc oxide powder is prepared. For example, when Ga and Ti are contained in addition to Zn, gallium oxide powder and titanium oxide powder are prepared in addition to zinc oxide powder, weighed so as to have a predetermined ratio, and mixed with a ball mill or the like. By mixing using an apparatus, a sintered raw material powder is obtained.

(Temporary firing step S02)
Next, the sintered raw material powder is tentatively fired. In the present embodiment, the sintered raw material powder is inserted into the carbon crucible and temporarily fired in a vacuum atmosphere. In this temporary firing step S02, the entire sintered raw material powder is slightly reduced. _In the temporary firing step S02, the sintered raw material powder may be temporarily fired in a reducing atmosphere such as CO gas or H2 gas.
Here, the degree of vacuum in the temporary firing step S02 is within the range of 15 Pa or less, the firing temperature is within the range of 600 ° C. or higher and 1000 ° C. or lower, and the holding time at the firing temperature is within the range of 2 hours or more and 6 hours or less. ing.

(Crushing step S03)
Next, the sintered raw material powder temporarily fired in the temporary firing step S02 is crushed using a ball mill device or the like.

(Sintering step S04)
The crushed sintered raw material powder is filled in a molding die, pressed and heated to be sintered, and a sintered body is obtained. In this embodiment, sintering is performed by a hot press device.
The sintering temperature at this time shall be in the range of 900 ° C. or higher and 1100 ° C. or lower, the holding time at the sintering temperature shall be in the range of 2 hours or longer and 6 hours or lower, and the pressurizing pressure shall be in the range of 10 MPa or higher and 35 MPa or lower. Is preferable. The atmosphere is preferably a vacuum atmosphere (15 Pa or less).
A sufficient density can be obtained by setting the sintering temperature to 900 ° C. or higher. On the other hand, by setting the sintering temperature to 1100 ° C. or lower, sublimation of zinc oxide can be suppressed, and composition deviation and occurrence of cracking of the sintered body can be suppressed.

(Machining process S05)
Next, the obtained sintered body is machined. As a result, the oxide sputtering target according to the present embodiment is manufactured.

The oxide sputtering target of the present embodiment having the above configuration is composed of an oxide sintered body containing Zn as a main component as a metal component, and the coefficient of variation of the specific resistance value in the thickness direction is 0. Since it is suppressed to 20 or less, it is possible to suppress variations in the film resistance of the formed oxide film even when sputtering progresses, and to stably form a uniform oxide film. Is possible.

Further, in the present embodiment, assuming that the total of the metal components is 100 atomic%, Ga is 10.0 atomic% or more and 20.0 atomic% or less, Ti is 0.5 atomic% or more and 5.0 atomic% or less, and the balance is Zn. When the oxide film is composed of an oxide contained in a proportion of an unavoidable impurity metal element, an oxide film can be stably formed by a normal sputtering method such as a DC (DC) sputtering method. In addition, an oxide film having excellent environmental resistance and alkali resistance can be formed.

In addition to Zn, Ga, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, B, Al, In, Si, Ge, Sn, Pb, Sb, The total of at least one or two or more additive elements selected from the element group consisting of Bi and lanthanoid series elements, and the total of the metal components is 100 atomic%, and the range is 0.01 atomic% or more and 10.0 atomic% or less. When it is contained inside, an oxide film having higher environmental resistance and a lower resistance value can be formed.

Further, in the present embodiment, when the composite oxide is contained and the abundance ratio of the composite oxide is 15% or more, the oxide sintered body becomes dense and cracks and cracks are more surely generated during sputtering. Can be suppressed.

The method for producing an oxide sputtering target according to the present embodiment includes a tentative firing step S02 for tentatively firing the sintered raw material powder, in which the degree of vacuum in the tentative firing step S02 is within the range of 15 Pa or less and the firing temperature is 600. Since the holding time at the firing temperature is within the range of 2 hours or more and 6 hours or less within the range of ° C. or higher and 1000 ° C. or lower, the sintering raw material powder can be slightly reduced in advance, and in the subsequent sintering step. The local reduction reaction can be suppressed. As a result, at least the difference in the degree of reduction in the thickness direction of the sputtered surface becomes small, and the variation in the specific resistance value in the thickness direction can be suppressed.

Further, in the present embodiment, the degree of vacuum in the sintering step S04 is within the range of 15 Pa or less, the sintering temperature is within the range of 900 ° C. or higher and 1100 ° C. or lower, and the holding time at the sintering temperature is 2 hours or longer and 6 hours or lower. When it is within the range, the composite oxide can be sufficiently produced and a dense oxide sintered body can be obtained.

Although the embodiments of the present invention have been described above, the present invention is not limited to this, and can be appropriately changed without departing from the technical idea of the invention.
For example, in the present embodiment, the description is given as a flat plate-shaped sputtering target, but the present invention is not limited to this, and a cylindrical-shaped sputtering target may be used. In this case, the thickness direction is the radial direction of the cylinder.

Further, in the present embodiment, a protective film for an optical recording medium, a steam barrier film for various devices such as a liquid crystal display element, an organic EL element, and a solar cell, and a wiring film for an electronic device such as a touch panel, a solar cell, and an organic EL display. Although it has been described as being used when forming an oxide film as a protective film for an electrode, the present invention is not limited to this, and a film used for other purposes may be formed.

The results of the evaluation test for evaluating the action and effect of the present invention will be described below.

As raw material powder, zinc oxide (ZnO) powder with an average particle size of 1 μm and a purity of 99.50 mass% or more, gallium oxide (Ga ₂ O ₃ ) powder with an average particle size of 2 μm and a purity of 99.99 mass% or more, and an average particle size of 15 μm. Titanium oxide (TiO ₂ ) powder having a purity of 99.00 mass% or more was prepared.
These raw material powders were weighed so as to have the composition shown in Table 1 and mixed uniformly with a ball mill device to obtain sintered raw material powders.

The obtained sintered raw material powder was filled in a carbon crucible, and temporary firing (vacuum firing) was carried out under the conditions shown in Table 1. Then, the calcined raw material powder that had been calcined was crushed by a ball mill device.
The sintered raw material powder after crushing was charged into a hot press device in a state of being filled in a carbon mold, and hot-pressed under the conditions of atmosphere: vacuum, pressure 25 MPa, sintering temperature and holding time time shown in Table 1. ..
By grinding the obtained sintered body, Examples 1 to 8 and Comparative Examples 1 to 5 of the present invention having the same composition as the compounding composition of Table 1 having a diameter of 178 × 126 × 6 mm. Oxide sputtering target was prepared.

The obtained oxide sputtering targets of Examples 1 to 14 of the present invention and Comparative Examples 1 to 5 were evaluated for the following items. The evaluation results are shown in Table 2.

(Abundance ratio of composite oxide)
Observation samples were taken from the oxide sputtering targets of Examples 1 to 14 of the present invention and Comparative Examples 1 to 5, X-ray diffraction measurement (XRD) was performed, and the intensity of the main peak of each phase was according to the procedure described in the embodiment. The abundance ratio of the composite oxide was calculated from. The X-ray diffraction measurement (XRD) conditions are shown below.
Equipment: Made by Rigaku Denki Co., Ltd. (RINT-Ultima / PC)
Tube: Cu
Tube voltage: 40kV
Tube current: 40mA
Scanning range (2θ): 10 to 90 degrees Slit: Divergence (DS) 2/3 degree, Scattering (SS) 2/3 degree,
Light receiving (RS) 0.8 mm
Measurement step width: 0.04 degrees at 2θ Scan speed: 2 degrees per minute Sample table rotation speed: 30 rpm

The main peaks of each measured phase are shown below.
ZnO: (101) ICDD 01-080-0074
TiO ₂ : (110) ICDD 01-076-1939
Ga ₂ O ₃ : (111) ICDD 01-087-1901
ZnGa ₂ O ₄ : (311) ICDD 01-086-0410
ZnTIO ₃ : (104) ICDD 00-026-1500
Zn ₂ TiO ₄ : (311) ICDD 00-025-1164

(Specific resistance)
The specific resistance values were measured on the sputtered surface of the oxide sputtering targets of Examples 1 to 14 of the present invention and the surface ground by 1 mm from the sputtered surface, the surface grinded by 2 mm, and the surface grinded by 3 mm, respectively. The specific resistance value was measured by a four-probe method using a low resistivity meter (Loresta-GP) manufactured by Mitsubishi Chemical Corporation. The temperature at the time of measurement was 23 ± 5 ° C., and the humidity was 50 ± 20%.
The mean value and standard deviation were obtained from the measurement results of four points, and the coefficient of variation of the specific resistance value in the thickness direction was calculated by acid.

(Membrane resistance of oxide film)
Using the oxide sputtering targets of Examples 1 to 14 of the present invention and Comparative Examples 1 to 5, an oxide film having a film thickness of 40 nm was sputtered onto a glass substrate under the following conditions.
Power supply: DC
Power: 300W
Total pressure: 0.67Pa
Gas: Ar: 50.0sccm

The film resistance of the oxide film formed at the initial stage of spatter film formation and the oxide film formed 2 hours after the start of spatter film formation was measured as follows.
The film resistance was measured by a four-probe method using a low resistivity meter (Loresta-GP) manufactured by Mitsubishi Chemical Corporation.

(Presence / absence of cracks / cracks after spattering)
The presence or absence of cracks and cracks in the oxide sputtering target after the sputtering deposition was carried out for 2 hours under the above conditions was evaluated.
On the surface of the sputtering target, those having cracks and cracks having a length of 2 mm or more are evaluated as having cracks / cracks, and those having no cracks / cracks having a length of 2 mm or more are evaluated as having cracks / cracks. evaluated.

In Comparative Example 1, the firing temperature in the temporary firing step was 400 ° C., and the coefficient of variation of the specific resistance value of the oxide sputtering target was as large as 0.210. As a result, the film resistance changed significantly between the oxide film formed at the initial stage of sputter film formation and the oxide film formed 2 hours after the start of sputter film formation.

In Comparative Example 2, the holding time at the firing temperature in the temporary firing step was set to 1 hour, and the coefficient of variation of the specific resistance value of the oxide sputtering target was as large as 0.220. As a result, the film resistance changed significantly between the oxide film formed at the initial stage of sputter film formation and the oxide film formed 2 hours after the start of sputter film formation.

In Comparative Example 3, the temporary firing step was not carried out, and the coefficient of variation of the specific resistance value of the oxide sputtering target became as large as 0.270. As a result, the film resistance changed significantly between the oxide film formed at the initial stage of sputter film formation and the oxide film formed 2 hours after the start of sputter film formation.

In Comparative Examples 4 and 5, the temporary firing step was not carried out, and the coefficient of variation of the specific resistance value of the oxide sputtering target became as large as 0.240 and 0.310, respectively. As a result, the film resistance changed significantly between the oxide film formed at the initial stage of sputter film formation and the oxide film formed 2 hours after the start of sputter film formation. Further, in Comparative Examples 4 and 5, the contents of Ga and Ti were smaller than those in Comparative Example 3, and the composite oxide was not sufficiently produced. Therefore, cracks having a length of 2 mm or more were confirmed after the sputtering film formation.

On the other hand, in Examples 1 to 14 of the present invention, the firing temperature in the temporary firing step is within the range of 600 ° C. or higher and 1000 ° C. or lower, and the holding time at the firing temperature is within the range of 2 hours or more and 6 hours or less. The fluctuation coefficient of the specific resistance value of the oxide sputtering target was 0.20 or less. As a result, the amount of change in film resistance was suppressed between the oxide film formed at the initial stage of sputter film formation and the oxide film formed 2 hours after the start of sputter film formation.

In addition, Example 7 of the present invention in which the holding time at the sintering step was 1 hour in the sintering step, Example 8 of the present invention in which the sintering temperature was 750 ° C. in the sintering step, and the firing temperature of 600 in the temporary firing step. In Example 11 of the present invention set at ° C. and Example 13 of the present invention in which the holding time at the firing temperature was 2 hours in the calcination step, the composite oxide was not sufficiently formed and the length was 2 mm or more after the sputter film formation. Crack was confirmed.

From the above results, according to the example of the present invention, an oxide sputtering target capable of stably forming a uniform oxide film with little variation in characteristics at the initial / middle / final stage of sputtering deposition, and an oxide thereof. It was confirmed that it is possible to provide a method for manufacturing a sputtering target.

Claims (6)

It consists of an oxide sintered body whose main component is Zn as a metal component.
An oxide sputtering target characterized in that the coefficient of variation of the specific resistance value in the thickness direction is 0.20 or less. Assuming that the total of the metal components is 100 atomic%, Ga is 10.0 atomic% or more and 20.0 atomic% or less, Ti is 0.5 atomic% or more and 5.0 atomic% or less, and the balance is Zn and unavoidable impurity metal elements. The oxide sputtering target according to claim 1, which comprises an oxide contained in a proportion thereof. Further, it is composed of elements of the Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe, Co, Ni, B, Al, In, Si, Ge, Sn, Pb, Sb, Bi and lanthanoid series. It is characterized by containing at least one or two or more additive elements selected from the element group in the range of 0.01 atomic% or more and 10.0 atomic% or less, with the total metal component as 100 atomic%. The oxide sputtering target according to claim 2. The oxide sputtering target according to any one of claims 2 or 3, wherein the oxide sputtering target has a composite oxide and the abundance ratio of the composite oxide is 15% or more. The method for manufacturing an oxide sputtering target for manufacturing the oxide sputtering target according to any one of claims 1 to 4.
A temporary firing step of temporarily firing the sintered raw material powder, a crushing step of crushing the fired sintered raw material powder, and a sintering step of sintering the crushed sintered raw material powder to obtain a sintered body. Equipped with
It is characterized in that the degree of vacuum in the temporary firing step is within the range of 15 Pa or less, the firing temperature is within the range of 600 ° C. or higher and 1000 ° C. or lower, and the holding time at the firing temperature is within the range of 2 hours or more and 6 hours or less. A method for manufacturing an oxide sputtering target. The degree of vacuum in the sintering step is within the range of 15 Pa or less, the sintering temperature is within the range of 900 ° C. or higher and 1100 ° C. or lower, and the holding time at the sintering temperature is within the range of 2 hours or more and 6 hours or less. The method for producing an oxide sputtering target according to claim 5.

Images