JPH09209134A - Target and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a target capable of stably forming a transparent conductive film in which the sheet resistance is approximately regulated to 800 to 10kΩ/square by a d.c. sputtering method and to provide a method for producing the same. SOLUTION: Indium (In) and at least one kind of metallic elements selected from the groups consisting of titanium(Ti), iridium(Ir), yttrium(Y), chromium(Cr), zirconium(Zr), hafnium(Hf), tantalum(Ta), cobalt(Co), bismuth(Bi) and manganese(Mn), and oxygen(O) are used as constituting elements. Then, the atomic ratio of the total content of the metallic elements selected from this group (total metallic atoms/(In + total metallic atoms) is regulated to 2.0 to 40at%, and the volume resistivity is regulated to >=5×10<-2> Ω.cm is used as a target.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sputtering target (hereinafter, simply referred to as "target") used when forming a transparent conductive film by a sputtering method, and a method for manufacturing the same, and more particularly to oxide firing. The present invention relates to a target composed of a unit and a method for manufacturing the target.

[0002]

2. Description of the Related Art In recent years, a touch panel (including a touch screen, the same applies hereinafter), a tablet, a digitizer as an input device for inputting data to a computer main body (main storage device) such as a personal computer, a word processor, and an electronic notebook. A coordinate input device such as is used.

There are various principles of this coordinate input device. For example, in a touch panel of a method called an analog type, a transparent base material and a transparent electrode film (resistor formed in a flat film on the transparent base material are used. 2) transparent electrode substrate with
The transparent electrode films are arranged so as to face each other at a predetermined interval by a spacer or the like.
One of the transparent electrode substrates is located on the input surface side. Then, when a load is applied from the outside of the transparent electrode substrate located on the input surface side and the transparent electrode films are electrically connected to each other, a portion where the above-mentioned electrical connection is generated from a predetermined end portion of one transparent electrode film is A circuit is so constructed that a current flows to a predetermined end of the other transparent electrode film. Since the electric resistance value in this circuit changes according to the position coordinates of the place where the conduction occurs, that is, the position where the load is applied, based on the change in the electric resistance value,
The position coordinates of the place where the load is applied are detected by the coordinate detecting means.

Therefore, the transparent electrode film used in the analog type touch panel has a higher electric resistance and is excellent in the sheet resistance uniformity than the transparent electrode film used in the coordinate input device according to another method. Is required. With the recent demand for improved input accuracy and lower power consumption, transparent electrode films used in analog touch panels have excellent transparency as well as sheet resistance of 800Ω / □ to 10 kΩ. / □
It has come to be required to have a high degree of electrical resistance.

Conventionally, an ITO film formed by a physical vapor deposition method has been widely used as a transparent electrode film, but the specific resistance of an ITO film formed by a physical vapor deposition method is generally 5 × 10 ⁻⁴ Ω · cm. Less than Therefore, in order to obtain a transparent electrode film having a sheet resistance of 800Ω / □ by using such an ITO film, the film thickness of the ITO film is 6n.
It is necessary to make it very thin, about m. However, such an extremely thin film does not go out of the region of an island structure ("Basic Technology of Thin Film" (The University of Tokyo Press) Nos. 90-9).
(See page 1) Therefore, it is not practically usable. Therefore, for a transparent electrode film used particularly for an analog type touch panel, development of a new high electric resistance film replacing the ITO film is desired.

As a film having a higher electric resistance than the ITO film,
A transparent conductive film is known in which indium oxide is doped with tin oxide together with silicon oxide and / or aluminum oxide in a predetermined amount (see Japanese Patent Laid-Open No. 4-206403). According to the above-mentioned publication, this transparent conductive film can be produced by an electron beam vapor deposition method, a sputter vapor deposition method, an ion plating method or the like, and it is most preferable that the transparent conductive film is produced by the sputter vapor deposition method from the viewpoint of uniformity. It is a conductive film. This transparent conductive film is suitable as a transparent electrode film of an analog type touch panel in terms of sheet resistance, light transmission and environment resistance.

[0007]

However, when a target made of an oxide is used when the transparent conductive film disclosed in the above publication is formed by the sputtering method, both silicon oxide and aluminum oxide are electrical insulators. Therefore, the volume resistivity of the target becomes high. When DC sputtering is performed using a target having a high volume resistivity, abnormal discharge is induced during film formation, and it is difficult to obtain a target film with good reproducibility. Moreover, when a target having a high volume resistivity is used,
The target is easily cracked. The induction of abnormal discharge due to the high volume resistivity of the target can be prevented by forming the film by the high frequency sputtering method, but the high frequency sputtering method has a slower film forming rate than the direct current sputtering method. Become.

By performing reactive sputtering using an alloy target, it is possible to form a target transparent conductive film while preventing induction of abnormal discharge and cracking of the target even during film formation by the DC sputtering method. Is. However, in the reactive sputtering method using an alloy target, it is necessary to control the amount of oxygen introduced at the time of film formation with extremely high precision as compared with a normal sputtering method or a reactive sputtering method using an oxide target. However, it is not suitable as a method for obtaining the target transparent conductive film with good reproducibility.

The object of the present invention is to have a sheet resistance of approximately 800.
An object of the present invention is to provide a target capable of stably forming a transparent conductive film having an Ω / □ to 10 kΩ / □ by a DC sputtering method, and a method for manufacturing the target.

[0010]

Means for Solving the Problems As a result of intensive studies for achieving the above-mentioned object, the present inventors have found that direct-current sputtering can be performed by using an oxide sintered body having a specific composition and electrical characteristics as a target. It was found that a transparent conductive film having a sheet resistance of approximately 800Ω / □ to 10 kΩ / □ can be stably formed by the method as well.

The present invention has been completed based on the above findings, and the target of the present invention is indium (I).
n) and titanium (Ti), iridium (Ir), yttrium (Y), chromium (Cr), zirconium (Z
r), hafnium (Hf), tantalum (Ta), cobalt (Co), bismuth (Bi) and manganese (Mn)
At least one metal element selected from the group consisting of and oxygen (O) as constituent elements, and the atomic ratio of the total amount of metal elements selected from the group (total metal atoms) / (In + total metal atoms) Is 2.0 to 40 at%, and the summary is that the volume resistivity is 5 × 10 ⁻² Ω · cm or less (hereinafter, this target is referred to as “target T”).
1 ”. ).

Other targets of the present invention include indium (In) and tin (Sn), titanium (Ti), iridium (Ir), yttrium (Y), chromium (C).
r), zirconium (Zr), hafnium (Hf), tantalum (Ta), cobalt (Co), bismuth (Bi)
And at least one metal element selected from the group consisting of manganese (Mn) and oxygen (O) as constituent elements, and the atomic ratio of the indium (In) is In / (In + S
n + total metal atoms) is 60 to 95 at%, and the atomic ratio Sn / (In + Sn + total metal atoms) of the tin (Sn) is 2.8 to 2
0 at%, the atomic ratio (In + Sn) / (In + Sn + total metal atoms) of the total amount of the indium (In) and the tin (Sn) is 62.8 to 98 at%, and the total amount of the metal elements selected from the group is Atomic ratio (total metal atoms) / (In + Sn + total metal atoms) is 2.0 to 37.2 at% and is made of an oxide sintered body, and the volume resistivity is 5 × 10 ⁻² Ω · cm or less. This is the gist (hereinafter, this target is referred to as "target T2").

On the other hand, the target manufacturing method of the present invention is
Indium (In) oxide and titanium (Ti), iridium (Ir), yttrium (Y), chromium (Cr),
Mixed oxidation with an oxide of at least one metal element selected from the group consisting of zirconium (Zr), hafnium (Hf), tantalum (Ta), cobalt (Co), bismuth (Bi) and manganese (Mn). Indium (In) includes a raw material preparation step for obtaining a product, a molding step for molding the mixed oxide obtained in the raw material preparation step, and a sintering step for sintering the molded article obtained in the molding step.
And titanium (Ti), iridium (Ir), yttrium (Y), chromium (Cr), zirconium (Zr), hafnium (Hf), tantalum (Ta), cobalt (C).
o), at least one metal element selected from the group consisting of bismuth (Bi) and manganese (Mn), and oxygen (O) as constituent elements, and the atomic ratio of the total amount of the metal elements selected from the group (All metal atoms) / (In + all metal atoms) is 2.0 to 40 at%, and volume resistivity is 5 × 10 ⁻² Ω
-The gist is to obtain a target composed of an oxide sintered body having a size of cm or less (hereinafter, this method is referred to as "method I").

Another method of manufacturing a target of the present invention is to use indium (In) oxide and tin (Sn) oxide, titanium (Ti), iridium (Ir), yttrium (Y), and chromium (Cr). , Zirconium (Zr), hafnium (Hf), tantalum (Ta), cobalt (C
o), a raw material preparation step of obtaining a mixed oxide with an oxide of at least one metal element selected from the group consisting of bismuth (Bi) and manganese (Mn), and the mixture obtained in the raw material preparation step The method includes a forming step of forming an oxide and a sintering step of sintering the formed product obtained in the forming step, and includes indium (In) and tin (Sn), titanium (Ti), iridium (Ir), Yttrium (Y), Chromium (Cr), Zirconium (Zr), Hafnium (Hf), Tantalum (Ta), Cobalt (C
o), at least one metal element selected from the group consisting of bismuth (Bi) and manganese (Mn) and oxygen (O) as constituent elements, and the atomic ratio of the indium (In) is In / (In + Sn + total) Metal atom) is 60 to 95 at
%, The atomic ratio Sn / (In + Sn + total metal atoms) of the tin (Sn) is 2.8 to 20 at%, and the indium (In) is
And the total atomic ratio of the tin (Sn) (In + Sn) /
(In + Sn + total metal atoms) is 62.8 to 98 at%, and the atomic ratio (total metal atoms) / (In + Sn + total metal atoms) of the total amount of metal elements selected from the above group is 2.0 to 37.2.
The gist is to obtain a target composed of an oxide sintered body having a volume resistivity of 5 × 10 ⁻² Ω · cm or less at at% (hereinafter, this method is referred to as “method II”).

[0015]

Embodiments of the present invention will be described below in detail. First, the target T1 of the present invention will be described. The target T1 includes, as described above, indium (In), titanium (Ti), iridium (Ir), yttrium (Y), chromium (Cr), zirconium (Zr). , Hafnium (Hf), tantalum (T
a), at least one metal element selected from the group consisting of cobalt (Co), bismuth (Bi) and manganese (Mn) and oxygen (O) as constituent elements, and a metal selected from the above group Atomic ratio of total amount of elements (all metal atoms)
/ (In + total metal atoms) is an oxide sintered body having a content of 2.0 to 40 at%.

Here, the reason why the atomic ratio of the total amount of the metal elements selected from the above group in the oxide sintered body is limited as described above is that the atomic ratio deviates from the above range.
The specific resistance of the transparent conductive film obtained by the sputtering method using the oxide sintered body as a target is 9.6 ×.
This is because it tends to be less than 10 ⁻⁴ Ω · cm, or it becomes difficult to set the volume resistivity of the oxide sintered body to 5 × 10 ⁻² Ω · cm or less.

The specific resistance of the obtained transparent conductive film is 9.6 × 1.
If it is less than 0 ⁻⁴ Ω · cm, the sheet resistance of the transparent conductive film is less than 800 Ω / □ even if the thickness of the transparent conductive film is the minimum film thickness (about 12 nm) that can be practically used, and the sheet resistance is 800 Ω / □.
If it is less than □, the electrical characteristics required for a high resistance electrode film for obtaining an analog touch panel with improved input accuracy cannot be satisfied. Also, the volume resistivity is 5 × 10 ^-2 Ω ・
If the oxide sintered body having a diameter of more than cm is used as a target for direct-current sputtering using the oxide sintered body as a target, defects such as abnormal discharge are induced and the target is cracked are likely to occur. In addition, "all metal atoms" in the formula representing the above-mentioned atomic ratio means the total number of atoms (relative value) of the metal elements selected from the above group (target T2, method I and The same applies to Method II).

When the above-mentioned oxide sintered body is used as a target, the composition and film forming conditions of the target are adjusted to thereby obtain about 9.6 × 10 ^{−4 to} 2.0 × 1.
It is possible to form a transparent conductive film having various specific resistances within the range of 0 ⁻¹ Ω · cm. Therefore, the composition of the oxide sintered body can be appropriately selected according to the electrical characteristics of the target transparent conductive film as long as the oxide sintered body satisfies the conditions for the volume resistivity described later. .

For example, in order to obtain an analog touch panel with improved input accuracy, the sheet resistance is approximately 800.
Ω / □ to 10 kΩ / □, preferably 800 to 5000 Ω
/ □, more preferably 1000 to 3000 Ω / □, further preferably 2000 to 3000 Ω / □, and a specific resistance of 9.
6 × 10 ^{−4 to} 2 × 10 ⁻¹ Ω · cm, more preferably 3 ×
10 ^{−3 to} 9 × 10 ⁻³ Ω · cm, more preferably 6 × 10
Since it is desirable to obtain a transparent electrode film having a density of ^{−3 to} 9 × 10 ⁻³ Ω · cm, in order to obtain such a transparent electrode film (transparent conductive film), the sputtering rate of each component, film forming conditions, etc. Taking into consideration, the composition of the oxide sintered body is appropriately adjusted. Further, in order to obtain a transparent conductive film having a high electric resistance with high stability over time,
The atomic ratio (total metal atoms) / (In + total metal atoms) of the total amount of the metal elements in the above oxide sintered body is 2.5 to 3
It is preferably 0 at%, particularly preferably 3.0 to 15 at%.

In the present invention, the volume resistivity of the above oxide sintered body is limited to 5 × 10 ⁻² Ω · cm or less as described above. The reason is that the oxide sintered body has a volume resistivity of 5 × 10 5.
This is because if it exceeds ⁻² Ω · cm, abnormal discharge is likely to be induced or the target is likely to be cracked when DC sputtering is performed using the oxide sintered body as a target. The volume resistivity of the oxide sintered body is 2 x 1
It is preferably 0 ⁻² Ω · cm or less, and 1 × 10 ⁻² Ω
-It is particularly preferable that it is not more than cm.

The volume resistivity of the oxide sintered body is 5 × 10 ^-2 Ω
-From the standpoint of making cm or less, it is preferable to obtain an oxide sintered body having a relative density of 80% or more using a raw material having a purity of 99% or more. The purity of the raw material is more preferably 99.9% or more, further preferably 99.99% or more. The relative density of the oxide sintered body is more preferably 90% or more, further preferably 95% or more. When the volume resistivity of the oxide sintered body after sintering exceeds 5 × 10 ^-2 Ω · cm, the oxide sintered body is annealed in a vacuum or a reducing atmosphere after sintering. The oxide sintered body having a volume resistivity of 5 × 10 ⁻² Ω · cm or less can be obtained by reducing the.

It is preferable that the relative density of the oxide sintered body is 80% or more in order to secure a sufficient film forming speed and to obtain a transparent conductive film having high light transmittance. Is. Here, the relative density refers to the actual density of the sintered body with respect to the theoretical density calculated from the composition of the oxide in terms of surface fraction (the same applies to the target T2 described later).

The target T1 of the present invention comprising an oxide sintered body having the above-mentioned composition and the above-mentioned volume resistivity.
Has a volume resistivity of the target T1 of 5 × 10 ^-2 Ω.
Since it is less than or equal to cm, even when it is used as a target for forming a transparent conductive film by a DC sputtering method, abnormal discharge is unlikely to be induced during the film formation or a crack is generated in the target, which is stable. It is possible to form a film. Further, stable film formation is possible even when the transparent conductive film is formed by a sputtering method other than the DC sputtering method, for example, a high frequency sputtering method.

The film obtained by the sputtering method using the target T1 of the present invention is indium (In).
And a metal element selected from the above group and oxygen (O)
As the constituent elements, and the atomic ratio (total metal atoms) / (In + total metal atoms) of the total amount of the metal elements is approximately 2.2 to 40 at.
% Oxide film. Since the visible light transmittance of this oxide film is approximately 85% or more when the film thickness is 200 nm, the oxide film has a film thickness of 200 nm.
It becomes possible to use suitably as a transparent conductive film by setting it as the following.

The specific resistance of the transparent conductive film is adjusted by appropriately adjusting the composition thereof including oxygen, in other words, by appropriately adjusting the composition and film forming conditions of the target T1 of the present invention. When the thickness is 12 nm, it is approximately 9.6 × 10 ^{−4 to} 1.2 × 10 ⁻² Ω · cm, and the film thickness is 20.
At 0 nm, it is approximately 1.6 × 10 ^{-2 to} 2.0 × 10 ^-1 Ω.
・ Since it can be set to cm, the film thickness is 12 to
Sheet resistance at 200 nm is approximately 800 Ω / □ to 1
It can be set to 0 kΩ / □. Such a transparent conductive film having a high electric resistance is particularly suitable as a transparent electrode film for obtaining an analog touch panel with improved input accuracy, and is also suitable as an electromagnetic wave shielding material or the like. The target T1 of the present invention can be manufactured by various methods, but it is preferable to manufacture it by the method I of the present invention described later.

Next, the target T2 of the present invention will be described. As described above, the target T2 of the present invention includes indium (In) and tin (Sn), and titanium (T).
i), iridium (Ir), yttrium (Y), chromium (Cr), zirconium (Zr), hafnium (H
f), at least one metal element selected from the group consisting of tantalum (Ta), cobalt (Co), bismuth (Bi) and manganese (Mn), and oxygen (O) as constituent elements, and the indium ( In) atomic ratio In / (I
60 to 95 at% of n + Sn + all metal atoms, tin (S
The atomic ratio Sn / (In + Sn + all metal atoms) of n) is 2.
8 to 20 at%, the indium (In) and the tin (S)
n) total atomic ratio (In + Sn) / (In + Sn +
The total metal atoms) is 62.8 to 98 at%, the atomic ratio of the total amount of metal elements selected from the above group (total metal atoms) / (In
+ All metal atoms) is an oxide sintered body having 2.0 to 37.2 at%.

Here, the atomic ratio of indium (In), the atomic ratio of tin (Sn), the atomic ratio of the total amount of indium (In) and tin (Sn) in the oxide sintered body, and from the above group The reason for limiting the atomic ratio of the total amount of the selected metal elements respectively as described above is that when these atomic ratios deviate from the above range, the transparent obtained by the sputtering method using the oxide sintered body as a target. The specific resistance of the conductive film tends to be less than 9.6 × 10 ⁻⁴ Ω · cm, or the volume resistivity of the oxide sintered body is 5 × 10 5.
^This is because it becomes difficult to reduce it to ⁻² Ω · cm or less.

Even when the above oxide sintered body is used as a target, it can be adjusted to about 9.6 × 10 ^{−4 to} 2.0 × 1 by adjusting the composition of the target and film forming conditions.
It is possible to form a transparent conductive film having various specific resistances within the range of 0 ⁻¹ Ω · cm. Therefore, the composition of the above-mentioned oxide sintered body is not limited as long as the oxide sintered body satisfies the conditions for volume resistivity described later.
As described in the description of (1), it can be appropriately selected according to the electrical characteristics of the target transparent conductive film. From the standpoint of obtaining a transparent conductive film having a high electrical resistance with high temporal stability, the atomic ratio In / (In + Sn + total metal atoms) of indium (In) in the above oxide sintered body is 60 to 95 at%,
Tin (Sn) atomic ratio Sn / (In + Sn + all metal atoms)
Is particularly preferably 2.8 to 20 at%.

The target T2 of the present invention is composed of the above oxide sintered body in terms of composition, and its volume resistivity is 5 × 10 ⁻² Ω for the same reason as in the above-mentioned target T1.
・ Limited to cm or less, the volume resistivity is 2 × 10 ^-2 Ω
・ It is preferably less than or equal to cm, and 1 × 10 ^-2 Ω · cm
It is particularly preferred that:

The volume resistivity of the oxide sintered body is 5 × 10 ^-2 Ω
・ From the viewpoint of making it less than or equal to cm, the above target T1
Similarly to the above, it is preferable to obtain an oxide sintered body having a relative density of 80% or more by using a raw material having a purity of 99% or more. The purity of the raw material is more preferably 99.9% or more, further preferably 99.99% or more. The relative density of the oxide sintered body is more preferably 90% or more, further preferably 95% or more. Volume resistivity of the oxide sintered body after sintering is 5 ×
When it exceeds 10 ⁻² Ω · cm, as in the case of obtaining the target T1 described above, an annealing treatment is performed in a vacuum or a reducing atmosphere after sintering to reduce the oxide sintered body. , Volume resistivity is 5 × 10 ^-2 Ω · c
It is possible to obtain an oxide sintered body of m or less. Note that setting the relative density of the oxide sintered body to 80% or more is suitable from the viewpoint of securing a sufficient film-forming rate and also from the viewpoint of obtaining a transparent conductive film having high light transmittance.

The target T2 of the present invention comprising an oxide sintered body having the above-mentioned composition and the above-mentioned volume resistivity.
The target T2 has a volume resistivity of 5 × 10 ^-2 Ω.
Since it is less than or equal to cm, even when it is used as a target for forming a transparent conductive film by a DC sputtering method, abnormal discharge is unlikely to be induced during the film formation or a crack is generated in the target, which is stable. It is possible to form a film. Further, stable film formation is possible even when the transparent conductive film is formed by a sputtering method other than the DC sputtering method, for example, a high frequency sputtering method.

The film obtained by the sputtering method using the target T2 of the present invention has indium (In) and tin (Sn), a metal element selected from the above group, and oxygen (O) as constituent elements. , Indium (In)
The atomic ratio of In / (In + Sn + all metal atoms) is about 60
~ 95 at%, atomic ratio of tin (Sn) Sn / (In + Sn +
2.5 to 20 at% of all metal atoms and indium (I
n) and the total atomic ratio of tin (Sn) (In + Sn) /
(In + Sn + all metal atoms) is approximately 62.5 to 98.2.
at%, the atomic ratio (total metal atoms) / (In + total metal atoms) of the total amount of metal elements selected from the above group is approximately 1.8 to
The oxide film is 37.5 at%. Since the visible light transmittance of this oxide film is approximately 85% or more when the film thickness is 200 nm, the oxide film is preferably used as a transparent conductive film by setting the film thickness to 200 nm or less. It becomes possible to do.

The specific resistance of the transparent conductive film is adjusted by appropriately adjusting the composition of the transparent conductive film, including oxygen, in other words, by adjusting the composition and film forming conditions of the target T2 of the present invention. When the thickness is 12 nm, it is approximately 9.6 × 10 ^{−4 to} 1.2 × 10 ⁻² Ω · cm, and the film thickness is 20.
At 0 nm, it is approximately 1.6 × 10 ^{-2 to} 2.0 × 10 ^-1 Ω.
・ Since it can be set to cm, the film thickness is 12 to
Sheet resistance at 200 nm is approximately 800 Ω / □ to 1
It can be set to 0 kΩ / □. Such a transparent conductive film having a high electric resistance is particularly suitable as a transparent electrode film for obtaining an analog touch panel with improved input accuracy, and is also suitable as an electromagnetic wave shielding material or the like. The target T2 of the present invention can be manufactured by various methods, but it is preferable to manufacture it by the method II of the present invention described later.

Next, the method I of the present invention will be described.
As described above, the method I of the present invention is performed by using indium (I
n) oxide, titanium (Ti), iridium (Ir),
Yttrium (Y), Chromium (Cr), Zirconium (Zr), Hafnium (Hf), Tantalum (Ta), Cobalt (Co), Bismuth (Bi) and Manganese (M
n), a raw material preparation step of obtaining a mixed oxide with an oxide of at least one metal element selected from the group consisting of n), a molding step of molding the mixed oxide obtained in the raw material preparation step, And a sintering step of sintering the molded product obtained in the molding step. Hereinafter, the raw material preparation step, the molding step, and the sintering step will be described in this order.

(1) Raw Material Preparation Step In this step, indium (In) oxide, titanium (Ti), iridium (Ir), yttrium (Y),
Oxidation for at least one metal element selected from the group consisting of chromium (Cr), zirconium (Zr), hafnium (Hf), tantalum (Ta), cobalt (Co), bismuth (Bi) and manganese (Mn). A mixed oxide with a substance is obtained. The average particle size of the mixed oxide is 0.01 to 10 μm when the granulation treatment described below is not performed.
Is preferable, and 0.1 to 5 μm is more preferable. If the average particle size of the mixed oxide is less than 0.01 μm, coagulation tends to occur unless the granulation treatment described below is performed, and if the average particle size exceeds 10 μm, the mixing property decreases and it is difficult to obtain a dense sintered body. become.

In obtaining the above mixed oxide, oxides, chlorides, inorganic acid salts, and hydroxides of each component (indium (In) and a metal element selected from the above group) except oxygen are obtained. Etc. can be used as a raw material.
The purity of each raw material is preferably 99% or more, more preferably 99.9% or more, particularly preferably 99.9.
It is 9% or more. If the purity of the raw material is less than 99%, it becomes difficult to obtain a dense oxide sintered body or an oxide sintered body having a target volume resistivity.

When an oxide is used as a raw material for each component, a powder of each oxide (raw material) is divided into predetermined amounts by a ball mill so that a target T1 having a desired composition can be obtained.
The target mixed oxide can be obtained by putting it in a mixer such as a jet mill or a pearl mill and pulverizing and mixing them. At this time, crushing and mixing time is 1 to 10
It is preferably 0 hours, more preferably 5 to 50 hours, particularly preferably 10 to 50 hours. If it is less than 1 hour, mixing tends to be insufficient, and if it exceeds 100 hours, it is not economical. There are no special restrictions on the temperature during crushing and mixing,
Room temperature is preferred.

When a substance other than an oxide is used as the raw material of each component, the target T of the target composition is used.
In order to obtain 1, the above raw materials were put into a mixer such as a ball mill, a jet mill or a pearl mill in a predetermined amount, pulverized and mixed to obtain a mixture, and then the mixture was calcined to obtain the calcined product. The desired mixed oxide can be obtained by pulverizing with the above mixer or the like. The calcination temperature and calcination time at this time depend on the type of raw material,
Approximately 800 to 1600 ° C. and 1 to 100 hours are preferable.
If the temperature is lower than 800 ° C. or lower than 1 hour, thermal decomposition of the raw material tends to be insufficient, and if the temperature exceeds 1600 ° C. or higher than 100 hours, the raw material tends to sinter and coarsening of particles tends to occur. More preferable calcining temperature and calcining time are 1000 to 1300 ° C. and 2 to 50 hours.

The above-mentioned calcination / crushing treatment may be carried out once, or the mixed oxide obtained by crushing the calcined product may be further calcined / crushed a desired number of times. Further, the target mixed oxide may be obtained by performing the above-mentioned calcination / pulverization treatment using an oxide as a raw material of each component.

When the object to be calcined is a mixed oxide once obtained or an oxide as a raw material, the calcining temperature and calcining time are preferably about 800 to 1600 ° C. for 1 to 100 hours. If the temperature is lower than 800 ° C. or lower than 1 hour, thermal decomposition of the raw material tends to be insufficient, and if the temperature exceeds 1600 ° C. or higher than 100 hours, the raw material tends to sinter and coarsening of particles tends to occur. More preferable calcining temperature and calcining time are 1000 to 1300 ° C. and 2 to 50 hours.

The target mixed oxide can be prepared by granulating the mixed oxide obtained as described above or by granulating the raw materials of the respective components. . This granulation can be performed by a conventional method such as a spray dry method. When the granulation is performed by a spray dry method, a solution obtained by adding a binder such as polyvinyl alcohol to an aqueous solution or alcohol solution of the above mixed oxide or raw material is used. Granulation conditions vary depending on the solution concentration and the amount of binder added, but the average particle size of the granulated product is 1 to 100 μm, preferably 5
It is adjusted to be -100 μm, particularly preferably 10-100 μm. By performing this granulation, it is possible to improve the fluidity and filling properties during molding, but if the average particle size of the granulated product exceeds 100 μm, the fluidity and filling properties during molding will be poor, and granulation Has no effect.

(2) Forming Step In this step, the mixed oxide obtained in the above-mentioned raw material preparing step is formed into a desired shape prior to sintering. Molding can be performed by die molding, casting molding, injection molding, pressure molding, etc., but from the viewpoint of obtaining a sintered body with a high relative density, C
It is preferable to perform pressure molding by a method such as IP (cold isostatic pressure) and HIP (hot isostatic pressure). The shape of the molded body can be various shapes suitable as a target. Further, polyvinyl alcohol, methyl cellulose, polywax, oleic acid or the like may be used as a molding aid. The molding pressure is preferably 10 kg / cm ^{2 to} 100 t / cm ² , and more preferably 100 kg / cm ^{2 to} 100 t / cm ² . The molding time is preferably 10 minutes to 10 hours. If the molding pressure is less than 10 kg / cm ² or the molding time is 1
If it is less than 0 minutes, it becomes difficult to obtain a sintered body having a high relative density.

(3) Sintering Step In this step, the molded product obtained in the above molding step is sintered to obtain an oxide sintered body. As a sintering method, HIP sintering, hot press sintering, atmospheric pressure sintering or the like can be applied, but atmospheric pressure sintering is preferable from the viewpoint of economy. The sintering temperature is preferably 1200 to 1600 ° C, more preferably 12
50 to 1550 ° C., more preferably 1300 to 1500
° C. If the temperature is lower than 1200 ° C., it is difficult to obtain an oxide sintered body having a sufficient relative density. Therefore, it is difficult to obtain an oxide sintered body having a desired volume resistivity even if annealing described later is performed. Further, if the temperature exceeds 1600 ° C., compositional deviation easily occurs. Although the sintering time depends on the sintering temperature, it is preferably 1 to 50 hours, more preferably 2 hours.
-30 hours, particularly preferably 3-20 hours. If it is less than 1 hour, the sintering is not sufficiently performed, and if it exceeds 50 hours, it is not economical. The atmosphere during sintering is air or a reducing atmosphere. Examples of the reducing atmosphere include reducing gas atmospheres such as H ₂ , methane and CO, and inert gas atmospheres such as Ar and N ₂ .

The volume resistivity of the oxide sintered body obtained through the above-mentioned raw material preparation step, molding step and sintering step is 5 ×.
When it exceeds 10 ⁻² Ω · cm, the volume resistivity is 5 × 1 by performing the annealing process described below.
It is possible to obtain an oxide sintered body of 0 ⁻² Ω · cm or less.

Annealing Step In this step, when the volume resistivity of the oxide sintered body obtained in the above sintering step exceeds 5 × 10 ⁻² Ω · cm, the oxide sintered body is To reduce the volume resistivity thereof, and obtain an oxide sintered body having a target volume resistivity. Annealing is performed in a furnace such as a sintering furnace or a hot press reduction furnace under vacuum or in a reducing atmosphere. Examples of the reducing atmosphere include reducing gas atmospheres such as H ₂ , methane and CO, and inert gas atmospheres such as Ar and N ₂ .

When the annealing is performed in vacuum, the annealing temperature is preferably 200 to 1000 ° C, more preferably 200 to 700 ° C, and further preferably 200 to 50 ° C.
0 ° C. If the temperature is less than 200 ° C, sufficient reduction is not performed,
If it exceeds 1000 ° C., the indium oxide or zinc oxide in the sintered body is sublimated, resulting in a composition shift. The annealing time is preferably 1 to 50 hours, more preferably 2 to 30 hours, and further preferably 3 to 20 hours. If it is less than 1 hour, sufficient reduction is not performed, and if it exceeds 50 hours, it is not economical.

The annealing temperature in the case of performing the annealing in a reducing atmosphere is preferably 200 to 1000 ° C, more preferably 300 to 1000 ° C, further preferably 400 to 1000 ° C. If it is less than 200 ° C, sufficient reduction is not carried out, and if it exceeds 1000 ° C, it is not economical.
Similar to the above, the annealing time is preferably 1 to 50 hours, more preferably 2 to 30 hours, and further preferably 3 to.
20 hours. The color of the sintered body after annealing as described above becomes blacker than that before annealing.

By carrying out the above-mentioned raw material preparing step, forming step and sintering step, or by performing the above-mentioned annealing step if necessary after performing the above-mentioned sintering step, the objective of the present invention can be obtained. The target T1 can be obtained. Since this target T1 has a volume resistivity of 5 × 10 ⁻² Ω · cm or less, abnormal discharge is induced or cracking occurs even when it is used as a target for film formation by the DC sputtering method. It is difficult to do. Further, the target T1 is a target capable of stably forming a transparent conductive film having a sheet resistance of 800 Ω / □ to 10 kΩ / □ by a sputtering method such as a DC sputtering method or a high frequency sputtering method.

Next, the method II of the present invention will be described.
The method II of the present invention, as described above, uses indium (I
n) oxide and tin (Sn) oxide, and titanium (T
i), iridium (Ir), yttrium (Y), chromium (Cr), zirconium (Zr), hafnium (H
f) a raw material preparation step for obtaining a mixed oxide with an oxide of at least one metal element selected from the group consisting of tantalum (Ta), cobalt (Co), bismuth (Bi) and manganese (Mn) A molding step of molding the mixed oxide obtained in the raw material preparing step and a sintering step of sintering the molded product obtained in the molding step.

In Method II, the mixed oxide obtained in the raw material preparation step is tin (Sn) oxidation in addition to indium (In) oxide and oxide for at least one metal element selected from the above group. Although it differs from the above-mentioned method I in that it contains a substance, the raw material preparing step, the molding step and the sintering step are performed in the same manner as the above-mentioned method I except for this point. Therefore, only the newly added tin (Sn) oxide will be described in detail here, and details of other points in the raw material preparation step and the molding step, the sintering step, and the annealing step performed as necessary will be omitted.

In Method II, the mixed oxide containing the above tin (Sn) oxide is obtained in the raw material preparation step. In obtaining the mixed oxide, the indium (In) oxide In addition to the raw material and the raw material of the oxide of at least one metal element selected from the above group, the tin, the oxide, the chloride, the inorganic acid salt, the hydroxide and the like of tin (Sn) are added to the tin. These (Sn) oxides are used as raw materials, and each of these raw materials is used in a predetermined amount so that a target T2 having a desired composition can be obtained. The purity of each raw material used in Method II is preferably 99% or more, more preferably 99.9% or more, and particularly preferably 99.99% or more for the same reason as in Method I described above.

The volume resistivity of the oxide sintered body obtained through the raw material preparation step, the molding step and the sintering step is 5 × 10 ⁻² Ω · c.
If it exceeds m, an oxide sinter having a volume resistivity of 5 × 10 ⁻² Ω · cm or less can be obtained by performing the annealing step as in the method I described above. This annealing step can be performed as in Method I.

The target T2 of the present invention is obtained by performing the raw material preparing step, the forming step and the sintering step, or by performing the above-mentioned annealing step if necessary after the sintering step. be able to.
Since this target T2 has a volume resistivity of 5 × 10 ⁻² Ω · cm or less like the target T1 described above, abnormal discharge occurs even when it is used as a target for film formation by the DC sputtering method. It is difficult to induce or crack. Further, the target T2 is a target capable of stably forming a transparent conductive film having a sheet resistance of 800 Ω / □ to 10 kΩ / □ by a sputtering method such as a DC sputtering method or a high frequency sputtering method.

[0054]

Embodiments of the present invention will be described below. Example 1 (1) Preparation of Raw Material As shown in Table 1, 268 g of indium oxide (In ₂ O ₃ ) powder (average particle size 1 μm) having a purity of 99.8% and a purity of 9
9.5% titanium oxide (TiO ₂ ) powder (average particle size 1μ
m) 32 g was used as a raw material, and these were put together with ethanol and alumina balls in a pot made of polyimide and mixed for 2 hours with a planetary ball mill. The obtained mixed powder was calcined at 1000 ° C. for 5 hours in an air atmosphere, and then the obtained fired product was put into a polyimide pot together with ethanol and alumina balls, and pulverized with a planetary ball mill for 2 hours. Water and polyvinyl alcohol were added to the powder obtained as described above, mixed, and then granulated with a spray dryer to obtain a mixed oxide of indium oxide and titanium oxide having an average particle size of 10 μm. It was

(2) Molding The above mixed oxide powder was put into a mold, pre-molded by a mold press molding machine at a pressure of 100 kg / cm ² , and then 4 t / cm by a cold isostatic press molding machine. ^It was consolidated under a pressure of ² to obtain a disk-shaped molded product having a diameter of 4.1 inches and a thickness of 5.3 mm.

(3) Sintering The above-mentioned molded product was put into a sintering furnace, and 1500 ° C. in an air atmosphere.
And pressure-sintered for 4 hours to obtain an oxide sintered body. Next, the surface of this oxide sintered body was polished to reduce its size to a diameter of 4 mm.
An inch and a thickness of 5 mm were used to obtain a target (relative density 95%; one of the targets T1) made of an intended oxide sintered body. 20m from the above target
A test piece of m × 40 mm × 5 mm was cut out and its volume resistivity was measured by the four-terminal method. Also, using this test piece, SPS manufactured by Seiko Denshi Kogyo Co., Ltd.
The composition was analyzed by ICP analysis (inductively coupled plasma optical emission spectroscopy) using -1500VR, and based on this result, the atomic ratio In / (In + T) of indium (In) was calculated.
i) and the atomic ratio of titanium (Ti) Ti / (In + T
i) was calculated. Table 2 shows the results.

(4) Target Life Test Same as (1) to (3) above, with a diameter of 4 inches and a thickness of 5
A target made of an oxide sintered body having a disk shape of mm was prepared, and DC magnetron sputtering using this target was continuously performed for 100 hours under the condition that the target applied power was 5 W / cm ² , and abnormal discharge was induced during this period. The presence or absence of cracks and the presence of cracks in the target were observed. At this time, the backing plate of the target was made of copper, and the bonding material was indium metal. The presence or absence of the induction of abnormal discharge was visually observed from the view port of the chamber. In addition, the presence or absence of cracking of the target is confirmed by visually inspecting the target immediately after the abnormal discharge is induced and visually inspecting the target after the life test if the abnormal discharge is not induced. And Table 3 shows the results.

(5) Formation of transparent conductive film Diameter 4 inches and thickness 5 in the same manner as in the above (1) to (3).
A target (one of targets T1) made of an oxide sintered body having a disk shape of mm was prepared, and this target was used to perform DC magnetron sputtering under the following conditions: 5 cm (length) × 5 cm (width) × 1 mm Alkali-free glass (thickness) (# 705 manufactured by Corning Incorporated)
9) A transparent conductive film having a film thickness of 15 nm was formed on the film.

Sputtering device: HSM552 (manufactured by Shimadzu Corporation) Target size: 4 inches in diameter, 5 mm in thickness Discharge form: DC magnetron Discharge current: 0.2 A Background pressure: 5 × 10 ⁻⁴ Pa Introduced gas (atmosphere) Gas): 97 vol% Ar + 3 vol% O ₂ mixed gas Gas flow rate: 10 SCCM Pre-sputtering pressure: 2 × 10 ⁻¹ Pa Pre-sputtering time: 5 minutes Sputtering pressure: 2 × 10 ⁻¹ Pa Sputtering time: 10 seconds Substrate temperature: Room temperature

The sheet resistance and the specific resistance of the transparent conductive film obtained under the above conditions were determined. Table 3 also shows these results. The film thickness of the transparent conductive film is measured by the stylus method using DEKTAK3030 manufactured by Sloan, and the sheet resistance is measured by the four-terminal method using Loresta FP manufactured by Mitsubishi Petrochemical Co., Ltd. It was calculated by multiplying the sheet resistance by the film thickness. Further, the above transparent conductive film was subjected to a heat resistance test under the conditions of 130 ° C. and 400 hours in the atmosphere, and the value R / R ₀ of the sheet resistance R after the test with respect to the sheet resistance R ₀ before the test was obtained. The results are also shown in Table 3.

Examples 2 to 14 Example 1 except that the raw materials shown in Table 1 were used.
Preparation of raw materials, molding, and sintering are performed in the same manner as in (1) to (3), and a total of two targets (one target T1) made of the target oxide sintered body are prepared for each example. Obtained. ◎ With respect to these targets, the volume resistivity was measured and the composition analysis was performed in the same manner as in Example 1 using one of the two targets for each example, and the life test and A transparent conductive film is formed using a target in Example 1 (4) or (5).
The same items as those obtained in Example 1 were obtained for each transparent conductive film in the same manner as in Example 1. The results are shown in Table 2 or Table 3.

Example 15 Preparation of raw materials, molding and sintering were carried out in the same manner as in Examples 1 (1) to (3) except that calcination / pulverization treatment and granulation treatment with a spray dryer were omitted. Thus, a total of two targets (one of the targets T1) made of the target oxide sintered body were obtained. Using one of these targets, the volume resistivity was measured and the composition was analyzed in the same manner as in Example 1, the other target was used for the life test, and the transparent conductive film was manufactured using the target. The film was formed in the same manner as in Example 1 (4) or (5), and the same items as those obtained in Example 1 for the transparent conductive film were obtained in the same manner as in Example 1. The results are shown in Table 2 or Table 3.

Example 16 Examples 1 (1) to 1) except that the sintering temperature was 1200 ° C.
Preparation of raw materials, molding and sintering are performed in the same manner as in (3), and after sintering, annealing is performed by heat treatment in a vacuum sintering furnace at 950 ° C. for 2 hours to obtain the target oxide. Two targets (one target T1) made of a sintered body were obtained in total. Using one of these targets, the volume resistivity was measured and the composition was analyzed in the same manner as in Example 1, the other target was used for the life test, and the transparent conductive film was manufactured using the target. The film was formed in the same manner as in Example 1 (4) or (5), and the same items as those obtained in Example 1 for the transparent conductive film were obtained in the same manner as in Example 1. The results are shown in Table 2 or Table 3.

Example 17 As shown in Table 1, 250 g of indium oxide (In ₂ O ₃ ) powder (average particle size 1 μm) having a purity of 99.8% and a purity of 9
9.5% titanium oxide (TiO ₂ ) powder (average particle size 1μ
m) 20 g and tin oxide (SnO ₂ ) powder having a purity of 99.5% (average particle size 1 μm) 30 g were used as raw materials, and the other raw materials were prepared in the same manner as in Examples 1 (1) to (3). Then, molding and sintering were performed to obtain a total of two targets (one of targets T2) made of the target oxide sintered body. Using one of these targets, the volume resistivity was measured and the composition was analyzed in the same manner as in Example 1, the other target was used for the life test, and the transparent conductive film was manufactured using the target. The film was formed in the same manner as in Example 1 (4) or (5), and the same items as those obtained in Example 1 for the transparent conductive film were obtained in the same manner as in Example 1. The results are shown in Table 2 or Table 3.

Comparative Example 1 As shown in Table 1, indium oxide (In ₂ O ₃ ) powder having a purity of 90.5% was used.
The raw materials were prepared, molded, and sintered in the same manner as in (3) to obtain a total of two oxide sintered targets.
Using one of these targets, the volume resistivity was measured and the composition was analyzed in the same manner as in Example 1. As a result, as shown in Table 2, the volume resistivity was out of the limit range of the present invention. there were. Table 2 shows the measurement results of the volume resistivity and the composition analysis results. Further, the life test of the other target and the film formation of the transparent conductive film using the target were performed in the same manner as in Example 1 (4) or (5), and the transparent conductive film in Example 1 was used. The same items as obtained were obtained in the same manner as in Example 1. Table 3 shows these results.
Shown in

Comparative Example 2 Example 1 (1) to Example 1 except that the sintering temperature was 800 ° C.
Raw materials were prepared, molded and sintered in the same manner as in (3) to obtain a total of two oxide sintered targets. When one of these targets was used to measure the volume resistivity and analyze the composition in the same manner as in Example 1, the target obtained as described above had a relative density of 75% (see Table 2). ), The volume resistivity was out of the limit range of the present invention as shown in Table 2. Table 2 shows the measurement results of the volume resistivity and the composition analysis results.
In addition, the life test was performed using the other target and the transparent conductive film was formed using the target in Example 1.
The same procedure as in (4) or (5) was performed, and the same items as those in Example 1 were determined for the transparent conductive film in the same manner as in Example 1. Table 3 shows the results.

Comparative Example 3 As shown in Table 1, the amount of indium oxide (In ₂ O ₃ ) powder used was 298 g, and the amount of titanium oxide (TiO ₂ ) powder used was 2 g. The raw materials were prepared, molded and sintered in the same manner as in 1) to (3) to obtain a total of two targets made of an oxide sintered body. Using one of these targets, the volume resistivity was measured and the composition was analyzed in the same manner as in Example 1. As shown in Table 2, the targets obtained as described above had volume resistivity. The atomic ratios of titanium and titanium (Ti) were both outside the limits of the present invention. Table 2 shows the measurement results of the volume resistivity and the composition analysis results. Further, the life test of the other target and the film formation of the transparent conductive film using the target were performed in the same manner as in Example 1 (4) or (5), and the transparent conductive film in Example 1 was used. The same items as obtained were obtained in the same manner as in Example 1. Table 3 shows the results.

Comparative Example 4 As shown in Table 1, the amount of indium oxide (In ₂ O ₃ ) powder used was 191 g, and the amount of titanium oxide (TiO ₂ ) powder used was 109 g. 1) ~
Raw materials were prepared, molded and sintered in the same manner as in (3) to obtain a total of two oxide sintered targets. Using one of these targets, the volume resistivity was measured and the composition was analyzed in the same manner as in Example 1. As shown in Table 2, the target obtained as described above was titanium (Ti The atomic ratio of) was outside the range of the present invention. Table 2 shows the measurement results of the volume resistivity and the composition analysis results. Further, the life test of the other target and the film formation of the transparent conductive film using the target are performed in the same manner as in Example 1 (4) or (5),
Regarding the transparent conductive film, the same items as those obtained in Example 1 were obtained in the same manner as in Example 1. Table 3 shows the results.

[0069]

[Table 1]

[0070]

[Table 2]

[0071]

[Table 3]

As shown in Table 3, Example 1 to Example 1
Each of the targets prepared in 7 is unlikely to induce abnormal discharge or crack the target even when used as a target for forming a transparent conductive film by DC magnetron sputtering. This is because the volume resistivity of each target is 0.8 × 10 ^{−2 to} 3.9 × 10 ⁻² Ω · c.
This is because it is as low as m (see Table 2).

The transparent conductive films formed in Examples 1 to 17 have a specific resistance of 1.0 × 1 as shown in Table 3.
It is as high as 0 ^{−3 to} 9.4 × 10 ⁻³ Ω · cm, and its sheet resistance is also as high as 0.8 kΩ / □ to 8.2 kΩ / □. Each of the transparent conductive films of Examples 1 to 17 having such electrical characteristics has a low resistance change rate R / R ₀ of 1.1 to 1.3 (see Table 3). It is suitable as a transparent electrode film or a material thereof for obtaining an analog touch panel with improved input accuracy.

On the other hand, as shown in Table 3, each of the targets prepared in Comparative Example 1 and Comparative Example 3 was used after being sputtered for 18 hours or 50 hours continuously when used as a target for DC magnetron sputtering. Abnormal discharge is induced and the target cracks, and it cannot withstand long-term film formation. Therefore, when a transparent conductive film is formed by DC magnetron sputtering using these targets, it is necessary to frequently replace the targets, which is inefficient in production.

In the DC magnetron sputtering using the targets produced in Comparative Example 1 and Comparative Example 3, the abnormal discharge is induced and the target is cracked because the volume resistivity of these targets is 20.0 × 10.
^This is due to the high value of ⁻² Ω · cm or 7.3 × 10 ⁻² Ω · cm. The volume resistivity of the target produced in Comparative Example 1 is as high as 20.0 × 10 ⁻² Ω · cm.
It is presumed that this is because the purity of the indium oxide (In ₂ O ₃ ) powder used as the raw material was as low as 90.5%, and the volume resistivity of the target produced in Comparative Example 3 was 7.3 ×. It is speculated that the high value of 10 ^-2 Ωcm is due to the low atomic ratio of titanium (Ti) of 1.2 at%.

The target produced in Comparative Example 2 has a volume resistivity of 61.3 × 10 ⁻² Ω · cm, which is extremely high.
The C discharge itself did not occur. The volume resistivity of the target produced in Comparative Example 2 was as high as 61.3 × 10 ^-2 Ω · cm, and the relative density thereof was as low as 75% because the sintering temperature was as low as 800 ° C. It is presumed that this is due to this.

The target produced in Comparative Example 4 has a low volume resistivity of 0.2 × 10 ⁻² Ω · cm and is unlikely to induce abnormal discharge and crack the target even when used as a target for DC magnetron sputtering. However, the specific resistance of the transparent conductive film obtained by using this target is as low as 0.6 × 10 ⁻³ Ω · cm. Therefore, in order to obtain a transparent conductive film having a sheet resistance of 800 Ω / □ or more, its film thickness needs to be 8 nm or less,
Such a thin film is not practical because it does not leave the island structure region. Further, as is clear from the value of the resistance change rate R / R ₀ shown in Table 3, the transparent conductive film is a film having low heat resistance and is not practical from this point as well.

[0078]

As described above, according to the present invention, a transparent conductive film having a high sheet resistance of about 800Ω / □ to 10 kΩ / □ can be stably formed by a DC sputtering method which is advantageous in production. become.

Claims (9)

[Claims] 1. Indium (In) and titanium (T
i), iridium (Ir), yttrium (Y), chromium (Cr), zirconium (Zr), hafnium (H
f), tantalum (Ta), cobalt (Co), bismuth (Bi) and manganese (Mn), and at least one metal element selected from the group consisting of oxygen (O) as a constituent element. The atomic ratio (total metal atoms) / (In + total metal atoms) of the total amount of the selected metal elements is 2.0 to 4
It consists of an oxide sintered body of 0 at% and has a volume resistivity of 5 ×.
A target characterized by being 10 ⁻² Ω · cm or less. 2. Indium (In) and tin (Sn)
And titanium (Ti), iridium (Ir), yttrium (Y), chromium (Cr), zirconium (Zr), hafnium (Hf), tantalum (Ta), cobalt (C).
o), at least one metal element selected from the group consisting of bismuth (Bi) and manganese (Mn) and oxygen (O) as constituent elements, and the atomic ratio of the indium (In) is In / (In + Sn + total) Metal atom) is 60 to 95 at
%, The atomic ratio Sn / (In + Sn + total metal atoms) of the tin (Sn) is 2.8 to 20 at%, and the indium (In) is
And the total atomic ratio of the tin (Sn) (In + Sn) /
(In + Sn + total metal atoms) is 62.8 to 98 at%, and the atomic ratio (total metal atoms) / (In + Sn + total metal atoms) of the total amount of metal elements selected from the above group is 2.0 to 37.2.
It consists of oxide sintered body with at% and volume resistivity is 5 × 1.
A target characterized by being 0 ⁻² Ω · cm or less. 3. Indium (In) oxide and titanium (Ti), iridium (Ir), yttrium (Y),
Oxidation for at least one metal element selected from the group consisting of chromium (Cr), zirconium (Zr), hafnium (Hf), tantalum (Ta), cobalt (Co), bismuth (Bi) and manganese (Mn). Including a raw material preparation step of obtaining a mixed oxide with a product, a molding step of molding the mixed oxide obtained in the raw material preparation step, and a sintering step of sintering the molded product obtained in the molding step. , Indium (In) and titanium (Ti), iridium (Ir), yttrium (Y), chromium (Cr), zirconium (Zr), hafnium (Hf), tantalum (T)
a), at least one metal element selected from the group consisting of cobalt (Co), bismuth (Bi) and manganese (Mn) and oxygen (O) as constituent elements, and a metal element selected from the above group Atomic ratio of total amount of (total metal atoms) /
A method for producing a target, which comprises obtaining a target composed of an oxide sintered body having (In + total metal atoms) of 2.0 to 40 at% and a volume resistivity of 5 × 10 ⁻² Ω · cm or less. 4. Indium (In) oxide and tin (S
n) oxide, titanium (Ti), iridium (Ir),
Yttrium (Y), Chromium (Cr), Zirconium (Zr), Hafnium (Hf), Tantalum (Ta), Cobalt (Co), Bismuth (Bi) and Manganese (M
n), a raw material preparation step of obtaining a mixed oxide with an oxide of at least one metal element selected from the group consisting of n), a molding step of molding the mixed oxide obtained in the raw material preparation step, And a sintering step of sintering the molded product obtained in the molding step, including indium (In) and tin (Sn), and titanium (T
i), iridium (Ir), yttrium (Y), chromium (Cr), zirconium (Zr), hafnium (H
f), at least one metal element selected from the group consisting of tantalum (Ta), cobalt (Co), bismuth (Bi) and manganese (Mn), and oxygen (O) as constituent elements, and the indium ( In) atomic ratio In / (I
60 to 95 at% of n + Sn + all metal atoms, tin (S
The atomic ratio Sn / (In + Sn + all metal atoms) of n) is 2.
8 to 20 at%, the indium (In) and the tin (S)
n) total atomic ratio (In + Sn) / (In + Sn +
62.8 to 98 at% of all metal atoms, the atomic ratio of the total amount of metal elements selected from the above group (all metal atoms) / (In +
Sn + total metal atoms) is 2.0 to 37.2 at% and the volume resistivity is 5 × 10 ⁻² Ω · cm or less. . 5. The method according to claim 3, wherein in the raw material preparation step, a mixed oxide is obtained by using a raw material having a purity of 99% or more. 6. A calcining / grinding process and / or a predetermined process for obtaining a powdery mixed oxide after calcination of a predetermined raw material composition to obtain a calcined product in the raw material preparation step. The method according to any one of claims 3 to 5, wherein the raw material composition is granulated to obtain a granular mixed oxide. 7. The sintering temperature in the sintering step is 1200 to 16
The method according to any one of claims 3 to 6, which is 00 ° C. 8. The method according to claim 3, further comprising an annealing step of annealing the sintered body obtained in the sintering step. 9. The method according to claim 8, wherein the annealing temperature in the annealing step is 200 to 1000 ° C.