TW201900581A - Sn-Zn-O based oxide sintered body and method for producing same - Google Patents

Abstract

Provided are an Sn-Zn-O-based oxide sintered body of high density and low resistance that can be used in such applications as barrier films and protective films, and a production method therefor. This Sn-Zn-O-based oxide sintered body has zinc (Zn) and tin (Sn) as components, and additionally contains at least germanium (Ge), tantalum (Ta), and gallium (Ga) as components, the metal atom number ratios being between 0.1 and 0.3 inclusive for Sn/(Zn+Sn), between 0.0005 and 0.01 inclusive for Ge/(Zn + Sn + Ge + Ta + Ga), between 0.0005 and 0.01 inclusive for Ta/(Zn + Sn + Ge + Ta + Ga), and between 0.001 and 0.1 inclusive for Ga/(Zn + Sn + Ge + Ta + Ga), the specific resistance thereof being between 5 [Omega].cm and 12,000 [Omega].m inclusive, and the relative density thereof being 94% or greater.

Description

Sn-zn-O series oxide sintered body and manufacturing method thereof

The invention relates to Sn-Zn used as a sputtering target when manufacturing a transparent conductive film suitable for solar cells, liquid crystal surface elements, touch panels, and the like by a sputtering method of direct current sputtering and high frequency sputtering. -O-based oxide sintered body and its production method. This application claims priority based on Japanese Patent Application No. 2017-095982 filed in Japan on May 12, 2017, and its application content is incorporated herein by reference.

Transparent conductive films having high conductivity and high transmittance in the visible light region are used in surface elements such as solar cells, liquid crystal display elements, organic electroluminescence and inorganic electroluminescence, and electrodes for touch panels, etc. It is also used as various anti-fog transparent heating elements such as heat ray reflection film, antistatic film, refrigerated display cabinet, protective film, etc. for automobile windows or buildings.

As the transparent conductive film, tin oxide (SnO ₂ ) containing antimony or fluorine as a dopant, zinc oxide (ZnO) containing aluminum or gallium as a dopant, and indium oxide (tin oxide) containing tin as a dopant are known. In ₂ O ₃ ). In particular, an indium oxide (In ₂ O ₃ ) film containing tin as a dopant, that is, an In-Sn-O-based film system is called an ITO (Indium tin oxide) film, because it is a film with low resistance that is easy to obtain. And is widely used.

As a method for manufacturing the transparent conductive film, a sputtering method using direct current sputtering and high frequency sputtering is often used. The sputtering method is an effective method when film formation of a material having a low vapor pressure or precise film thickness control is necessary. Since the operation is very simple, it is widely used industrially.

In order to manufacture the transparent conductive film, conventionally, an indium oxide-based material such as ITO has been widely used. However, indium metal is a rare metal on the earth and is toxic. Therefore, it is necessary to have a non-indium-based material because of doubts about adverse effects on the environment or human body.

As the non-indium-based material, as described above, a zinc oxide (ZnO) -based material containing aluminum or gallium as a dopant and a tin oxide (SnO ₂ ) -based material containing antimony or fluorine as a dopant are known. material. In addition, the transparent conductive film of the zinc oxide (ZnO) -based material is industrially manufactured by a sputtering method, but has disadvantages such as lack of chemical resistance (alkali resistance, acid resistance) and the like. On the other hand, although a transparent conductive film of a tin oxide (SnO ₂ ) -based material is excellent in chemical resistance, it is difficult to manufacture a high-density and durable tin oxide-based sintered body target. Therefore, it is accompanied by difficulty in using sputtering. Disadvantages of manufacturing the above-mentioned transparent conductive film.

Therefore, as a material for improving these disadvantages, a sintered body having zinc oxide and tin oxide as main components has been proposed. For example, Patent Document 1 describes a Zn-Sn-O-based oxide sintered body which does not contain a crystalline phase of tin oxide or a crystalline phase of tin oxide in which zinc is solid-dissolved, but uses a zinc oxide phase and tin A zinc acid compound phase or a zinc stannate compound phase.

Further, Patent Document 2 describes a sintered body having an average crystal grain size of 4.5 μm or less and a (222) plane in a Zn ₂ SnO ₄ phase using X-ray diffraction using CuKα rays, ( When the cumulative intensity of the 400) plane is set to I ₍₂₂₂₎ and I ₍₄₀₀₎ , the orientation degree represented by I ₍₂₂₂₎ / [I ₍₂₂₂₎ + I ₍₄₀₀₎ ] is greater than the standard (0.44) 0.52 or more. Furthermore, Patent Document 2 also describes a method for forming a sintered body as a method of producing a sintered body having the above-mentioned characteristics by the following steps. This step is to include oxygen in a firing furnace in a firing furnace. In the environment of 800 ° C to 1400 ° C, firing the compact; and after the holding at the highest firing temperature is completed, the firing furnace is cooled to an inert environment such as Ar gas for cooling. step. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2007-277075 [Patent Document 2] Japanese Patent Laid-Open No. 2013-036073

[Problems to be Solved by the Invention]

However, in these methods, although the strength of a sintered body capable of withstanding mechanical strength can be obtained in a Sn-Zn-O-based oxide sintered body containing Zn and Sn as main components, it is difficult to obtain sufficient density or conductivity. The performance is not sufficient as a characteristic necessary for sputtering film formation at a mass production site. That is, in the normal pressure sintering method, there is still a problem in terms of achieving high density or conductivity of the sintered body.

The Sn-Zn-O based oxide sintered body containing Zn and Sn as main components is made of a material which is difficult to have both characteristics of high density and low resistance. Even if the blending ratio of Sn and Zn is changed, it is difficult to produce a high density An oxide sintered body having excellent conductivity. Although the density of the sintered body varies slightly depending on the blending ratio, it exhibits a very high specific resistance value of 1 × 10 ⁶ Ω ･ cm or more for conductivity, and lacks conductivity.

In the production of Sn-Zn-O based oxide sintered bodies with Zn and Sn as the main components, Zn ₂ SnO ₄ compounds start to be generated near 1100 ° C, and the volatilization of Zn starts at around 1400 ° C, starting from around 1450 ° C. Volatilization of Zn becomes apparent. If the firing is performed at a high temperature in order to increase the density of the Sn-Zn-O-based oxide sintered body, the volatilization of Zn progresses, so the grain boundary diffusion or the combination of grains is weak, and high density oxide sintering cannot be obtained. body.

Regarding conductivity, since Zn ₂ SnO ₄ , ZnO, and SnO ₂ are substances lacking conductivity, even if the blending ratio is adjusted to adjust the amount of the compound phase or the amount of ZnO and SnO ₂ , the conductivity cannot be significantly improved.

The sintered body of ITO used in the past has a specific resistance value of 2 to 3 × 10 ^-4 Ω ･ cm. The sintered body is used as a target for sputtering, and it is suitable to be used as a transparent conductive film such as a liquid crystal or a solar cell. . On the other hand, in recent years, although the conductivity is lower than that of ITO, there are applications in which it can be used as a barrier film such as a gas barrier film, a water vapor barrier film, or a protective film to protect it from damage or impact. The value is about 10Ω ･ cm ～ × 10 ⁴ Ω ･ cm. Therefore, a Sn-Zn-O-based oxide sintered body suitable for these conditions is required.

Therefore, an object of the present invention is to provide a Sn-Zn-O-based oxide sintered body with high density and low resistance, which can be used in applications such as barrier films and protective films, and a method for producing the same. [Means to solve the problem]

The present inventors have found that in order to solve the above-mentioned problems, Sn is contained in a ratio of Sn / (Sn + Zn) of 0.1 to 0.3 as an atomic ratio, and Ge, Ta, and Ga are contained in a specific ratio as an additive element. Three kinds of Sn-Zn-O-based oxide sintered bodies having a specific resistance value of about 10Ω ･ cm ～ × 10 ⁴ Ω ･ cm suitable for applications such as a barrier film or a protective film can be obtained. invention.

That is, the homogeneous system of the present invention is a Sn-Zn-O-based oxide sintered body having zinc (Zn) and tin (Sn) as components, and further containing at least germanium (Ge), tantalum (Ta), and gallium. (Ga) as a component, and the metal atomic ratio Sn / (Zn + Sn) is 0.1 or more and 0.3 or less, Ge / (Zn + Sn + Ge + Ta + Ga) is 0.0005 or more and 0.01 or less, and Ta / (Zn + Sn + Ge + Ta + Ga) is 0.0005 or more and 0.01 or less, Ga / (Zn + Sn + Ge + Ta + Ga) is 0.001 or more and 0.1 or less, the specific resistance is 5Ω ･ cm or more and 12000Ω ･ cm or less, and the relative density is 94% or more. .

According to the state of the present invention, three types of germanium (Ge), tantalum (Ta), and gallium (Ga) are used as an additive element such that Sn / (Sn + Zn) is at a ratio of 0.1 to 0.3, In addition, it can be a Sn-Zn-O-based oxide sintered body which can be used in applications such as a barrier film or a protective film with high density and low resistance.

At this time, in the state of the present invention, the metal atomic ratio system Sn / (Zn + Sn) can be set to be 0.16 or more and 0.23 or less, the specific resistance is 5Ω ･ cm or more and 110Ω ･ cm or less, and the relative density is 98% or more. .

As such, by further limiting Sn / (Zn + Sn), a Sn-Zn-O-based oxide sintered body having a high density and a low resistance can be further realized.

In the aspect of the present invention, in the Sn-Zn-O-based oxide sintered body, the wurtzite-type crystal structure of the ZnO phase may be 5 to 70% of the whole (in this specification, "~ ”Means a range that means the lower limit is greater than the upper limit, and the same applies below), or the Zn ₂ SnO ₄ phase with a spinel crystal structure is in a range of 30 to 95% of the total.

By setting the metal atomic ratio as in the present invention, a Sn-Zn-O-based oxide sintered body having the above-mentioned crystal structure is obtained.

Also, another aspect of the present invention is a method for producing a sintered body of Sn-Zn-O oxide having zinc (Zn) and tin (Sn) as components, which includes the following steps: powder of zinc oxide, tin A granulation process for preparing a granulated powder by mixing an oxide powder and an oxide powder containing an additive element; a forming step of pressing the granulated powder to obtain a formed body; and firing the formed body In the firing step of obtaining an oxide sintered body, the aforementioned additional elements are at least germanium (Ge), tantalum (Ta), and gallium (Ga) so that the metal atomic ratio becomes Sn / (Zn + Sn) of 0.1 or more and 0.3 or less. Below, Ge / (Zn + Sn + Ge + Ta + Ga) is 0.0005 or more and 0.01 or less, Ta / (Zn + Sn + Ge + Ta + Ga) is 0.0005 or more and 0.01 or less, Ga / (Zn + Sn + Ge + Ta + Ga) is 0.001 or more and 0.1 or less to mix the zinc oxide powder, the tin oxide powder, and the additive element-containing oxide powder.

According to another aspect of the present invention, three types of germanium (Ge), tantalum (Ta), and gallium (Ga) are used as an additive element so that Sn / (Zn + Sn) becomes a ratio of 0.1 to 0.3. By mixing in a specific ratio, a high density and low resistance Sn-Zn-O based oxide sintered body can be produced which can be used in applications such as barrier films and protective films.

At this time, in another aspect of the present invention, it is preferable that the temperature is raised to 1300 ° C or higher and 1400 ° C or lower at a heating rate of 0.3 to 1.0 ° C / min under a firing furnace atmosphere in the atmosphere in the firing step. The formed body is fired under conditions of 15 hours to 25 hours.

By firing the molded body under the above conditions, a Sn-Zn-O-based oxide sintered body with higher density and low resistance can be produced. [Inventive effect]

According to the present invention, it becomes a Sn-Zn-O-based oxide sintered body which can be used as a barrier film, a protective film, or the like with high density and low resistance.

Hereinafter, the Sn-Zn-O-based oxide sintered body and the method for producing the same according to the present invention will be described in the following order with reference to the drawings. The present invention is not limited to the following examples, and can be arbitrarily changed without departing from the gist of the present invention. 1.Sn-Zn-O based oxide sintered body 2.Sn-Zn-O based oxide sintered body manufacturing method 2-1. Granulation step 2-2. Molding step 2-3. Sintering step

<1. Sn-Zn-O-based oxide sintered body> First, the Sn-Zn-O-based oxide sintered body of the present invention will be described. The Sn-Zn-O-based oxide sintering system according to an embodiment of the present invention contains Sn as a ratio of the atomic ratio Sn / (Sn + Zn) of 0.1 or more and 0.3 or less, as a total amount relative to the total metal element. The ratio of the number of atoms Ge / (Sn + Zn + Ge + Ta + Ga) is 0.0005 or more and 0.01 or less. The first additive element Ge is included, and the ratio of the number of atoms to the total metal elements is Ta / (Sn + Zn + Ge + Ta + Ga) contains 0.002 or more and 0.01 or less and contains the second additive element Ta, and the atomic ratio Ga / (Sn + Zn + Ge + Ta + Ga) as the total amount of the total metal elements is given by The third additive element Ga is contained at a ratio of 0.001 to 0.1. As such, the specific resistance of the Sn-Zn-O-based oxide sintering system according to one embodiment of the present invention is 5 Ω ･ cm or more and 12000 Ω ･ cm or less, and the relative density is 94% or more.

Tin oxide and zinc oxide which are the main raw materials of the Sn-Zn-O based oxide sintered body according to an embodiment of the present invention will be only zinc oxide tin compounds, or raw material powders containing a mixed powder of tin oxide and zinc oxide. Sn is contained in such a proportion that the atomic ratio Sn / (Sn + Zn) is 0.1 or more and 0.3 or less.

Due to the Sn content, a difference was observed in the crystal structure of the sintered body after sintering. When Sn is contained at a ratio of Sn / (Sn + Zn) of 0.1 to 0.3, the ZnO phase of the wurtzite crystal structure and the Zn ₂ SnO ₄ phase of the spinel crystal structure become the main components . In a case where the ratio exceeds 0.3, 0.9 or less contained, Zn spinel type crystal structure of SnO ₂ SnO ₄ phase and a rutile type crystal structure mainly composed of ₂ complementary. When the main component of the SnO ₂ phase of the rutile crystal structure increases, the resistance value increases. Also, the transmittance will decrease.

The atomic ratio Sn / (Sn + Zn) is more preferably 0.16 to 0.23. In this range, the desired resistance value is obtained, and the density is preferably 98% or more, which is more preferable.

When manufacturing a Sn-Zn-O-based oxide sintered body, as described above, during sintering, Zn ₂ SnO ₄ compounds start to be formed from around 1100 ° C, and the volatilization of Zn begins to exceed 1400 ° C, and Zn starts from around 1450 ° C. The volatility becomes apparent. If the firing is performed at a high temperature in order to increase the density of the Sn-Zn-O-based oxide sintered body, the volatilization of Zn progresses, so the grain boundary diffusion or the combination of grains is weak, and high density oxide sintering cannot be obtained. body. On the other hand, regarding conductivity, since Zn ₂ SnO ₄ , ZnO, and SnO ₂ are substances lacking conductivity, even if the blending ratio is adjusted to adjust the amount of the compound phase or the amount of ZnO and SnO ₂ , the conductivity cannot be greatly increased. improve.

(Additive element) Therefore, in the present invention, in order to improve the above-mentioned conductivity, the first to third additive elements are added. That is, by adding germanium (Ge) as the first additive element, tantalum (Ta) as the second additive element, and gallium (Ga) as the third additive element, high density and low resistance Sn-Zn can be obtained. -O-based oxide sintered body.

[First Additive Element] In order to densify the oxide sintered body, the effect of high density can be obtained by adding the first additive element Ge. The first additive element, Ge, promotes grain boundary diffusion, and helps the crystal necks of the grains grow, so that the grains are strongly bonded to each other, thereby contributing to densification. Here, the reason why the atomic ratio Ge / (Sn + Zn + Ge + Ta + Ga) of the first additive element Ge to the total metal element is set to 0.0005 or more and 0.01 or less is because the atomic ratio Ge When (Sn + Zn + Ge + Ta + Ga) is less than 0.0005, the effect of high density cannot be exhibited (see Comparative Example 10). Even when the atomic ratio Ge / (Sn + Zn + Ge + Ta + Ga) exceeds 0.01, the effect of high density cannot be exhibited (see Comparative Example 9). And other compounds, such as Zn ₂ Ge ₃ O ₈ compounds, are formed.

However, when only the first additive element Ge is added, although the density of the oxide sintered body is increased, the conductivity is not improved.

[Second additive element] 烧结 Sn-Zn-O-based oxide to which the first additive element Ge is added is sintered under the condition that Sn is contained in a ratio of Sn / (Sn + Zn) of 0.1 to 0.3 in terms of atomic ratio. Although the density of the system is increased as described above, there is a problem in the conductivity.

Therefore, the second addition element Ta is added. The addition of the second additive element Ta improves the conductivity while maintaining the high density of the oxide sintered body. The second additive element Ta is an element having a valence of 5 or more.

The amount of addition must be such that the atomic ratio Ta / (Sn + Zn + Ge + Ta + Ga) of the second additive element Ta to the total metal element is 0.0005 or more and 0.01 or less. When the atomic ratio Ta / (Sn + Zn + Ge + Ta + Ga) is less than 0.0005, the conductivity cannot be improved (see Comparative Example 12). On the other hand, when the atomic ratio Ta / (Sn + Zn + Ge + Ta + Ga) exceeds 0.01, other compound phases such as compound phases such as Ta ₂ O ₅ and ZnTa ₂ O ₆ are generated. Therefore, the conductivity is deteriorated (see Comparative Example 11).

[Third Additive Element] As described above, the addition of the second additive element Ta improves the conductivity. However, Ta is replaced with Sn and SnO _{2 in the} Zn ₂ SnO ₄ phase to perform solid solution. Therefore, the desired conductivity may not be obtained in some cases.

Therefore, the third addition element Ga is added. The addition of the third additive element Ga is expected to improve the conductivity of Zn in the Zn and Zn ₂ SnO ₄ phases.

The amount of addition must be such that the atomic ratio Ge / (Sn + Zn + Ge + Ta + Ga) of the third additive element Ge to the total metal element is 0.001 or more and 0.1 or less. When the atomic ratio Ga / (Sn + Zn + Ge + Ta + Ga) is less than 0.001, the conductivity cannot be improved. (Refer to Comparative Example 14). On the other hand, when the above-mentioned atomic ratio Ga / (Sn + Zn + Ge + Ta + Ga) exceeds 0.1, other compound phases such as a compound phase such as Ga ₂ O _{3 may} be formed, and thus conductive. Sexual deterioration (see Comparative Example 13).

In addition, as long as the characteristics of the Sn-Zn-O-based oxide sintered body as one embodiment of the present invention are not impaired, it can be used in applications such as barrier films or protective films, and has a high density (relative density of 94% or more) and Those having low resistance (specific resistance is 5 Ω ･ cm or more and 12000 Ω ･ cm or less) may further include an additive element. Examples of further additional element systems include Si, Ti, Bi, Ce, Al, Nb, W, Mo, and the like.

(X-ray diffraction peak) In the Sn-Zn-O-based oxide sintered body according to an embodiment of the present invention, when the atomic ratio Sn / (Sn + Zn) is 0.1 or more and 0.3 or less, wurtzite-type crystals The ZnO phase of the structure and the Zn ₂ SnO ₄ phase of the spinel-type crystal structure become the main components. In addition, appropriate amounts of the first additive element Ge, the second additive element Ta, and the third additive element Ga will interact with Zn in the ZnO phase. Zn or Sn in the Zn ₂ SnO ₄ phase and Sn in the SnO ₂ phase for solid solution replacement. Therefore, ZnO phase with wurtzite type crystal structure and Zn ₂ SnO ₄ phase with spinel type crystal structure. No other compound phases will form.

(Specific resistance) The specific resistance of the Sn-Zn-O-based oxide sintered body according to an embodiment of the present invention is 5 Ω ･ cm or more and 12000 Ω ･ cm or less. As described above, the specific resistance of the oxide sintered body of Sn—Zn—O has a specific resistance value of 1 × 10 ⁶ Ω 为 cm or more in the past. In the present invention, the specific resistance value is reduced by doping Ge, Ta, and Ga as the first to third additive elements.

The sintered body of ITO used in the past has a specific resistance value of 2 to 3 × 10 ^-4 Ω ･ cm. The sintered body is used as a target for sputtering, and it is suitable to be used as a transparent conductive film for liquid crystal or solar electronics. . A transparent conductive film obtained by sputtering using a Sn-Zn-O oxide sintered body according to an embodiment of the present invention has a specific resistance of about 10 Ω ･ cm to 1 × 10 ⁴ Ω ･ cm. It is inferior to ITO, but can be used in applications such as gas barrier films, water vapor barrier films, or barrier films that protect against damage or impact. The oxide sintering system of Sn-Zn-O according to one embodiment of the present invention is suitable for the specific resistance of sputtering of a film having a specific resistance of about 10 Ω ･ cm to 1 × 10 ⁴ Ω ･ cm.

The specific resistance value of the sputtered film will also be affected by the film formation conditions during sputtering, especially the oxygen concentration during sputtering. However, if the productivity during sputtering, the uniformity of the film, and the like are considered, it is preferable that the specific resistance value of the film is consistent with the specific resistance value of the crystal.

Since the specific resistance value depends on the film formation speed during sputtering, the smaller the specific resistance value, the better. Since the specific resistance of the Sn-Zn-O-based oxide sintered body according to an embodiment of the present invention is 5 Ω ･ cm or more and 12000 Ω ･ cm or less, it is an oxide sintered body suitable for sputtering. In the case where the specific resistance is less than 5 Ω 由于 cm, the resistance value of the obtained film becomes low, so that leakage from a nearby electrode becomes a problem. In addition, if the specific resistance value exceeds 12000 Ω ･ cm, it becomes difficult to perform discharge, and film formation cannot be performed stably with respect to DC sputtering, which is a problem.

Furthermore, in one embodiment of the present invention, by setting the metal atomic ratio to Sn / (Zn + Sn) to be 0.16 or more and 0.23 or less, the specific resistance value can be set to a range of 5Ω ･ cm to 110Ω ･ cm. (Refer to Examples 1, 8, and 9). By setting the specific resistance value to be 5 Ω ･ cm or more and 110 Ω ･ cm or less, the film formation speed is increased, and it is more preferable.

(Relative density) The relative density of the Sn-Zn-O-based oxide sintered body according to an embodiment of the present invention is 94% or more. As shown in Patent Document 1, in an oxide sintered body of Sn-Zn-O blended at a ratio of Sn / (Sn + Zn) of 0.23 to 0.5, the relative density is due to sintering. When Zn is volatilized, crystals with high relative density cannot be obtained. In the present invention, the relative density can be increased by blending the aforementioned additional elements in a specific amount.

The relative density can be increased to 98% or more by setting the metal atomic ratio Sn / (Zn + Sn) to 0.16 or more and 0.23 or less. When the relative density is 98% or more, the strength of the target is increased and the film formation speed during sputtering is increased. At the same time, the outgassing of the target is reduced, and it becomes a stable film formation.

<2. Manufacturing method of Sn-Zn-O-based oxide sintered body> Next, the manufacturing method of the Sn-Zn-O-based oxide sintered body of the present invention will be described. An embodiment of the present invention is a method for producing a sintered body of Sn-Zn-O oxide having zinc (Zn) and tin (Sn) as components, which includes the following steps: oxidizing zinc oxide powder and tin A granulation step S1 for preparing a granulated powder by mixing an object powder and an oxide powder containing an additive element; a forming step S2 in which the granulated powder is pressure-molded to obtain a formed body; and the formed body is fired Then, a firing step S3 of the oxide sintered body is obtained. For example, the Sn-Zn-O oxide sintering system according to an embodiment of the present invention is blended with a specific ratio of raw material powder containing only zinc tin oxide compounds or mixed powders of tin oxide and zinc oxide. Germanium oxide with 1 added element, tantalum oxide with 2nd added element, and gallium oxide with 3rd added element are granulated, and the granulated powder is formed by cold equal pressure, etc., and the formed body is fired in a firing furnace. To obtain a sintered body. Hereinafter, each step will be described individually.

(2-1. Granulation step) First, in a granulation step S1, a main raw material is prepared. The tin oxide and zinc oxide system that will be the main raw materials will be only zinc tin oxide compounds, or raw material powders containing mixed powders of tin oxide and zinc oxide, with an atomic ratio Sn / (Sn + Zn) of 0.1 to 0.3. The ratio contains Sn. The main raw material is preferably a mixed powder of tin oxide and zinc oxide, which can be easily adjusted. For example, the raw material powders are SnO ₂ powder and ZnO powder. In addition, an oxide containing the first additive element to the third additive element is prepared and added to the main raw material to prepare it. For example, a GeO ₂ powder as the first additive element Ge and a Ta ₂ O ₅ powder as the second additive element Ta and a Ga ₂ O ₃ powder as the third additive element Ga are prepared and added to the main raw material for blending.

In the granulation step S1, the metal atomic ratio is set such that Sn / (Zn + Sn) is 0.1 or more and 0.3 or less, Ge / (Zn + Sn + Ge + Ta + Ga) is 0.0005 or more and 0.01 or less, and Ta / (Zn + Sn + Ge + Ta + Ga) is 0.0005 or more and 0.01 or less, and Ga / (Zn + Sn + Ge + Ta + Ga) is 0.001 or more and 0.1 or less, so that zinc oxide powder, tin oxide powder, and The oxide powder containing the additive element is mixed. In this manner, the three kinds of germanium (Ge), tantalum (Ta), and gallium (Ga) are specified as the additive elements so that Sn / (Zn + Sn) becomes a ratio of 0.1 to 0.3, as described above. By mixing the ratios, a Sn-Zn-O-based oxide sintered body having a high density and a low resistance, which can be used in applications such as a barrier film or a protective film, can be produced.

Next, the prepared raw material powder and pure water or ultrapure water, an organic binder, a dispersant, and an antifoaming agent are mixed in a mixing tank so that the concentration of the raw material powder becomes a specific concentration. Then, the raw material powder is wet-pulverized using a bead mill or the like in which hard ZrO ₂ balls are put, and then mixed and stirred to obtain a slurry. A granulated powder can be obtained by spraying and drying the obtained slurry with a spray-drying device or the like.

(2-2. Molding step) The molding step S2 is a step of press-molding the granulated powder obtained in the granulation step S1 to obtain a compact. In the forming step S2, in order to remove voids between the particles of the granulated powder, for example, pressure forming is performed at a pressure of about 294 MPa (3.0 ton / cm ² ). Although the method for pressure forming is not particularly limited, for example, it is preferable that a rubber mold is filled with the granulated powder obtained in the granulation step S1, and a cold equalizing pressure (CIP: Cold Isostatic Press) capable of applying high pressure is preferably used. .

(2-3. Firing step) (1) The firing step S3 is based on a specific temperature rise rate in the firing furnace, and fires the formed body obtained in the above-mentioned forming step S2 under the conditions of a specific temperature and a specific time. , And the step of obtaining a sintered body. The firing step S3 is performed, for example, in an atmosphere inside a firing furnace. The method for producing a Sn-Zn-O-based oxide sintered body according to an embodiment of the present invention is also characterized by these firing conditions, and will be described in detail below.

[Heating rate] The heating rate in the sintering furnace from 700 ° C to a specific sintering temperature is preferably at a rate of 0.3 to 1.0 ° C / min, and the molded body is fired. It has the effect of promoting the diffusion of ZnO, SnO ₂ or Zn ₂ SnO ₄ compounds, improving sinterability, and improving conductivity. Moreover, by setting such a temperature increase rate, it is also effective in suppressing volatilization of ZnO or Zn ₂ SnO ₄ in a high temperature region.

In addition, in the method for manufacturing a Sn-Zn-O-based oxide sintered body according to an embodiment of the present invention, SnO _{2 may be present} during sintering (lower temperature range). However, Sn / (Zn + Sn) is 0.1 or more and 0.3 or less. When the sintering at the specified temperature is completed, the SnO ₂ phase disappears, and the diffraction peak of the SnO ₂ phase cannot be measured by X-ray diffraction analysis.

In the case where the temperature rise rate in the sintering furnace is less than 0.3 ° C / min, the diffusion of the compound will decline. When the temperature exceeds 1.0 ° C./min, the temperature rise rate is rapid, so that the formation of the compound is incomplete, and a dense sintered body cannot be produced. (See Comparative Examples 3 and 4).

[Sintering temperature] The sintering temperature is preferably set to 1300 ° C or higher and 1400 ° C or lower. When the sintering temperature is less than 1300 ° C (see Comparative Example 5), the temperature is too low, and the sintered grain boundary diffusion in the ZnO, SnO ₂ , and Zn ₂ SnO ₄ compounds does not proceed. On the other hand, even when the temperature exceeds 1400 ° C (see Comparative Example 6), although grain boundary diffusion is promoted and sintering proceeds, the volatilization of the Zn component cannot be suppressed, and a large number of voids remain in the sintered body.

[Hold time] The hold time is preferably set to 15 hours or more and 25 hours or less. If it is less than 15 hours, the sintering will be incomplete. Therefore, the sintered body will be deformed or warped, and the grain boundary diffusion will not proceed, and the sintering will not proceed. As a result, a dense sintered body cannot be produced (see Comparative Example 7). On the other hand, when it exceeds 25 hours, the volatilization of ZnO or Zn ₂ SnO ₄ increases, which results in a decrease in density, deterioration in work efficiency, and high cost (see Comparative Example 8).

The Sn-Zn-O-based oxide sintered body according to one embodiment of the present invention, which has Zn and Sn as main components, obtained under such conditions, has improved conductivity, and is therefore a film capable of DC sputtering. Moreover, since no special manufacturing method is used, it can also be applied to a cylindrical target. [Example]

Hereinafter, the present invention will be described in more detail using examples. However, the present invention is not limited to the following examples.

(Example 1) In Example 1, a SnO ₂ powder, a ZnO powder, a GeO ₂ powder as a first additive element Ge, a Ta ₂ O ₅ powder as a second additive element Ta, and a Ga as a third additive element were prepared. Ga ₂ O ₃ powder.

Next, the SnO ₂ powder and ZnO powder are blended so that the atomic ratio of Sn and Zn Sn / (Sn + Zn) is 0.2, so that the atomic number ratio of the first additive element Ge is Ge / (Sn + Zn + Ge + Ta + Ga) is 0.004, the atomic ratio of the second additive element Ta is Ta / (Sn + Zn + Ge + Ta + Ga) is 0.002, and the atomic ratio of the third additive element Ga is Ga / ((Sn + Zn + Ge + Ta + Ga) was adjusted to 0.02 to mix GeO ₂ powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder.

Next, the prepared raw material powder and pure water or ultrapure water, an organic binder, a dispersant, and an antifoaming agent are mixed in a mixing tank so that the concentration of the raw material powder becomes 55 to 65% by mass. Next, using a bead mill device (type LMZ, manufactured by Ashizawa Finetech Co., Ltd.) with hard ZrO ₂ balls, wet grinding was performed until the average particle diameter of the raw material powder became 1 μm or less, and the mixture was stirred for more than 10 hours to obtain a slurry. body. In addition, in order to measure the average particle diameter of the raw material powder, a laser diffraction type particle size distribution measuring device (SALD-2200, manufactured by Shimadzu Corporation) was used.

The obtained slurry was spray-dried with a spray-drying device (manufactured by Ogawara Chemical Machinery Co., Ltd., ODL-20 type) to obtain granulated powder.

Next, the obtained granulated powder was filled in a rubber mold, and formed by applying a pressure of 294 MPa (3ton / cm ² ) under cold equalizing pressure, and the formed body having a diameter of about 250 mm was put into a normal-pressure firing furnace, and the sintering furnace was used. Air was introduced into it until 700 ° C. After confirming that the temperature in the firing furnace was 700 ° C, oxygen was introduced, the temperature was raised to 1350 ° C, and the temperature was maintained at 1350 ° C for 20 hours. The temperature increase rate at this time was set to 0.7 ° C / min.

After the holding time was over, the introduction of oxygen was stopped and cooling was performed to obtain a Sn-Zn-O-based oxide sintered body of Example 1.

Next, the Sn-Zn-O-based oxide sintered body of Example 1 was processed into a diameter of 200 mm and a thickness of 5 mm using a surface grinder and a grinding center.

As a result of measuring the density of this processed body by the Archimedes method, the relative density was 99.0%. The specific resistance measured by the four-probe method was 5.5 Ω ･ cm.

In addition, a part of this processed body was cut and pulverized by a mortar to obtain a powder. This powder was analyzed using an X-ray diffraction device [X'Pert-PRO (manufactured by PANalytical)] with CuKα rays, and the spinel-type crystal structure had a Zn ₂ SnO ₄ phase of 66% and fiber zinc. The ZnO phase of the ore-type crystal structure has an overall diffraction of 34%, and the diffraction peaks of other compound phases have not been measured. These results are shown in Table 1.

(Example 2) In Example 2, the ratio of the atomic ratio of Sn and Zn Sn / (Sn + Zn) was set to 0.1, and other than that, an example was obtained in the same manner as in Example 1. 2 of Sn-Zn-O based oxide sintered body. As a result of X-ray diffraction analysis of the powder as in Example 1, the wurtzite-type ZnO phase was 70% and the spinel-type crystal structure of the Zn ₂ SnO ₄ phase was 30% diffraction. No diffraction peak was measured for the other compound phases. The relative density was 96.0%, and the specific resistance value was 1780 Ω ･ cm. These results are shown in Table 1.

(Example 3) In Example 3, blending was performed at a ratio of Sn / Zn atomic ratio Sn / (Sn + Zn) to 0.3. Except that, Example 1 was obtained in the same manner as in Example 1. Sn-Zn-O-based oxide sintered body of 3. As a result of X-ray diffraction analysis of the powder in the same manner as in Example 1, the wurtzite-type ZnO phase was 5%, and the spinel-type crystal structure of the Zn ₂ SnO ₄ phase was 95% diffraction. No diffraction peak was measured for the other compound phases. The relative density was 95.5%, and the specific resistance was 7100 Ω ･ cm. These results are shown in Table 1.

(Example 4) In Example 4, the ratio of the atomic ratio of Sn and Zn Sn / (Sn + Zn) was set to 0.1 so that the atomic ratio of the first additive element Ge was Ge / (Sn + Zn). + Ge + Ta + Ga) is 0.0005, the atomic ratio of the second additive element Ta is Ta / (Sn + Zn + Ge + Ta + Ga) is 0.0005, and the atomic ratio of the third additive element Ga is Ga / ( Sn + Zn + Ge + Ta + Ga) was set to 0.001 to prepare GeO ₂ powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder. Except that, the same method as in Example 1 was used to obtain an example. 4 of Sn-Zn-O based oxide sintered body. As in Example 2, the wurtzite-type ZnO phase was 70%, and the spinel-type crystal structure of the Zn ₂ SnO ₄ phase was 30% diffraction. No diffraction peak was measured for the other compound phases. The relative density was 95.0%, and the specific resistance was 5300 Ω ･ cm. These results are shown in Table 1.

Example 5 In Example 5, the ratio of the atomic ratio Sn / (Sn + Zn) of Sn and Zn to 0.1 was adjusted so that the atomic ratio of the first additive element Ge was Ge / (Sn + Zn). + Ge + Ta + Ga) is 0.01, the atomic ratio of the second additive element Ta is Ta / (Sn + Zn + Ge + Ta + Ga) is 0.01, and the atomic ratio of the third additive element Ga is Ga / ( Sn + Zn + Ge + Ta + Ga) was set to 0.1 so that GeO ₂ powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder were blended. Except that, Example 1 was obtained in the same manner as in Example 1. 5 of Sn-Zn-O based oxide sintered body. As in Example 2, the wurtzite-type ZnO phase was 70%, and the spinel-type crystal structure of the Zn ₂ SnO ₄ phase was 30% diffraction. No diffraction peak was measured for the other compound phases. The relative density was 96.0%, and the specific resistance value was 980 Ω980cm. These results are shown in Table 1.

(Example 6) In Example 6, the ratio of the atomic ratio Sn / (Sn + Zn) of Sn and Zn to 0.3 was adjusted so that the atomic ratio of the first additive element Ge was Ge / (Sn + Zn). + Ge + Ta + Ga) is 0.0005, the atomic ratio of the second additive element Ta is Ta / (Sn + Zn + Ge + Ta + Ga) is 0.0005, and the atomic ratio of the third additive element Ga is Ga / ( Sn + Zn + Ge + Ta + Ga) was set to 0.001 to prepare GeO ₂ powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder. Except that, the same method as in Example 1 was used to obtain an example. Sn-Zn-O-based oxide sintered body of 6. As in Example 3, the wurtzite-type ZnO phase was 5%, and the spinel-type crystal structure of the Zn ₂ SnO ₄ phase was 95% diffraction. No diffraction peak was measured for the other compound phases. The relative density was 94.7%, and the specific resistance was 10,000 Ω10000cm. These results are shown in Table 1.

(Example 7) In Example 7, the ratio of the atomic ratio Sn / (Sn + Zn) of Sn and Zn to 0.3 was adjusted so that the atomic ratio of the first additive element Ge was Ge / (Sn + Zn). + Ge + Ta + Ga) is 0.01, the atomic ratio of the second additive element Ta is Ta / (Sn + Zn + Ge + Ta + Ga) is 0.01, and the atomic ratio of the third additive element Ga is Ga / ( Sn + Zn + Ge + Ta + Ga) was set to 0.1 so that GeO ₂ powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder were blended. Except that, Example 1 was obtained in the same manner as in Example 1. Sn-Zn-O-based oxide sintered body of 7. As in Example 3, the wurtzite-type ZnO phase was 5%, and the spinel-type crystal structure of the Zn ₂ SnO ₄ phase was 95% diffraction. No diffraction peak was measured for the other compound phases. The relative density was 95.0%, and the specific resistance was 9500 Ω ･ cm. These results are shown in Table 1.

(Example 8) In Example 8, the ratio of the atomic ratio of Sn and Zn Sn / (Sn + Zn) was set to 0.16, and the sintering holding temperature was set to 1300 ° C. In the same manner as in Example 1, a Sn-Zn-O-based oxide sintered body of Example 8 was obtained. As a result of X-ray diffraction analysis of the powder as in Example 1, the Zn ₂ SnO ₄ phase of the spinel type crystal structure was 54%, and the ZnO phase of the wurtzite type crystal structure was 46% The diffraction peaks of other compound phases were not measured. The relative density was 98.0%, and the specific resistance value was 60 Ω ･ cm. These results are shown in Table 1.

(Example 9) In Example 9, the ratio of the atomic ratio of Sn and Zn Sn / (Sn + Zn) was 0.23, and the sintering holding temperature was set to 1400 ° C. In the same manner as in Example 1, a Sn-Zn-O-based oxide sintered body of Example 9 was obtained. As a result of X-ray diffraction analysis of the powder in the same manner as in Example 1, the Zn ₂ SnO ₄ phase of the spinel crystal structure was 74%, and the ZnO phase of the wurtzite crystal structure was 26% of the whole. The diffraction peaks of other compound phases were not measured. The relative density was 98.5%, and the specific resistance was 105Ω ･ cm. These results are shown in Table 1.

(Example 10) In Example 10, the ratio of the atomic ratio Sn / (Sn + Zn) of Sn and Zn to 0.3 was adjusted so that the atomic ratio of the first additive element Ge was Ge / (Sn + Zn). + Ge + Ta + Ga) is 0.0005, the atomic ratio of the second additive element Ta is Ta / (Sn + Zn + Ge + Ta + Ga) is 0.0005, and the atomic ratio of the third additive element Ga is Ga / ( Sn + Zn + Ge + Ta + Ga) was set to 0.001 to mix GeO ₂ powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder, and the sintering retention time was 15 hours. In the same manner, the Sn-Zn-O-based oxide sintered body of Example 10 was obtained. As in Example 6, the wurtzite-type ZnO phase was 5%, and the spinel-type crystal structure of the Zn ₂ SnO ₄ phase was 95% diffraction. No diffraction peak was measured for the other compound phases. The relative density was 94.0%, and the specific resistance value was 12000 Ω ･ cm. These results are shown in Table 1.

(Example 11) In Example 11, the ratio of the atomic ratio Sn / (Sn + Zn) of Sn and Zn to 0.3 was adjusted so that the atomic ratio of the first additive element Ge was Ge / (Sn + Zn). + Ge + Ta + Ga) is 0.01, the atomic ratio of the second additive element Ta is Ta / (Sn + Zn + Ge + Ta + Ga) is 0.01, and the atomic ratio of the third additive element Ga is Ga / ( Sn + Zn + Ge + Ta + Ga) was adjusted to 0.1 so that GeO ₂ powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder were prepared, and the sintering retention time was 25 hours. In the same manner, the Sn-Zn-O-based oxide sintered body of Example 11 was obtained. As in Example 3, the wurtzite-type ZnO phase was 5%, and the spinel-type crystal structure of the Zn ₂ SnO ₄ phase was 95% diffraction. No diffraction peak was measured for the other compound phases. The relative density was 95.5%, and the specific resistance value was 10,500 Ω ･ cm. These results are shown in Table 1.

(Example 12) In Example 12, the ratio of the atomic ratio of Sn and Zn Sn / (Sn + Zn) was set to 0.1 so that the atomic ratio of the first additive element Ge was Ge / (Sn + Zn). + Ge + Ta + Ga) is 0.01, the atomic ratio of the second additive element Ta is Ta / (Sn + Zn + Ge + Ta + Ga) is 0.01, and the atomic ratio of the third additive element Ga is Ga / ( Sn + Zn + Ge + Ta + Ga) is set to 0.1 so that GeO ₂ powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder are blended, and the heating rate is set to 0.3 ° C./min. In the same manner as in Example 1, a Sn-Zn-O-based oxide sintered body of Example 12 was obtained. As in Example 2, the wurtzite-type ZnO phase was 70%, and the spinel-type crystal structure of the Zn ₂ SnO ₄ phase was 30% diffraction. No diffraction peak was measured for the other compound phases. The relative density was 95.0%, and the specific resistance value was 1,320 Ω ･ cm. These results are shown in Table 1.

(Example 13) In Example 13, the ratio of the atomic ratio Sn / (Sn + Zn) of Sn and Zn to 0.1 was adjusted so that the atomic ratio of the first additive element Ge was Ge / (Sn + Zn). + Ge + Ta + Ga) is 0.0005, the atomic ratio of the second additive element Ta is Ta / (Sn + Zn + Ge + Ta + Ga) is 0.0005, and the atomic ratio of the third additive element Ga is Ga / ( Sn + Zn + Ge + Ta + Ga) was adjusted to 0.001 to mix GeO ₂ powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder, and the heating rate was set to 1.0 ° C./min. In the same manner as in Example 1, a Sn-Zn-O-based oxide sintered body of Example 13 was obtained. As in Example 2, the wurtzite-type ZnO phase was 70%, and the spinel-type crystal structure of the Zn ₂ SnO ₄ phase was 30% diffraction. No diffraction peak was measured for the other compound phases. The relative density was 94.5%, and the specific resistance was 6800 Ω ･ cm. These results are shown in Table 1.

(Comparative Example 1) In Comparative Example 1, a comparative example was obtained in the same manner as in Example 1 except that the atomic ratio of Sn and Zn was Sn / (Sn + Zn) at a ratio of 0.05. Sn-Zn-O-based oxide sintered body of No. 1. For the Sn-Zn-O-based oxide sintered body of Comparative Example 1, the results of X-ray diffraction analysis were performed in the same manner as in Example 1. The wurtzite-type ZnO phase was 90% and the spinel-type crystal structure was The Zn ₂ SnO ₄ phase is 10% diffraction. No diffraction peak was measured for the other compound phases. As a result of measuring the relative density and specific resistance, the relative density was 93.0%, and the specific resistance was 3510 Ω ･ cm. That is, it was confirmed that a relative density of 94% or more and a specific resistance of 5 Ω ･ cm or more and 12000 Ω ･ cm or less could not be achieved. The results are shown in Table 2.

(Comparative Example 2) In Comparative Example 2, a comparison example was obtained in the same manner as in Example 1 except that the atomic ratio Sn / (Sn + Zn) of Sn and Zn was adjusted to a ratio of 0.40. 2 of Sn-Zn-O based oxide sintered body. For the Sn-Zn-O-based oxide sintered body of Comparative Example 2, the results of X-ray diffraction analysis were performed in the same manner as in Example 1. The wurtzite-type ZnO phase was 0% and the rutile-type SnO ₂ phase was 14 %, And the spinel-type crystal structure of the Zn ₂ SnO ₄ phase is 86% diffraction. No diffraction peak was measured for the other compound phases. As a result of measuring the relative density and specific resistance value, the relative density was 89.0%, and the specific resistance value was 597,000 Ω ･ cm. That is, it was confirmed that it was impossible to achieve a relative density of 94% or more and a specific resistance of 5 Ω ･ cm or more and 12000 Ω 无法 cm or less. The results are shown in Table 2.

(Comparative Example 3) A Sn-Zn-O-based oxide sintered body of Comparative Example 3 was obtained in the same manner as in Example 1 except that the heating rate was set to 0.2 ° C / min in Comparative Example 3. . For the Sn-Zn-O-based oxide sintered body of Comparative Example 3, the results of X-ray diffraction analysis were performed in the same manner as in Example 1. The wurtzite-type ZnO phase was 34% and the spinel-type crystal structure was The Zn ₂ SnO ₄ phase is 66% diffracted. No diffraction peak was measured for the other compound phases. As a result of measuring the relative density and specific resistance, the relative density was 90.0%, and the specific resistance was 15000 Ω ･ cm. That is, it was confirmed that a relative density of 94% or more and a specific resistance of 5 Ω ･ cm or more and 12000 Ω ･ cm or less could not be achieved. The results are shown in Table 2.

(Comparative Example 4) A Sn-Zn-O-based oxide sintered body of Comparative Example 4 was obtained in the same manner as in Example 1 except that the heating rate was set to 1.2 ° C / min in Comparative Example 4. . For the Sn-Zn-O-based oxide sintered body of Comparative Example 4, the results of X-ray diffraction analysis were performed in the same manner as in Example 1. The wurtzite-type ZnO phase was 34% and the spinel-type crystal structure was the same. The Zn ₂ SnO ₄ phase is 66% diffracted. No diffraction peak was measured for the other compound phases. As a result of measuring the relative density and specific resistance, the relative density was 92.0%, and the specific resistance was 12500 Ω ･ cm. That is, it was confirmed that it was impossible to achieve a relative density of 94% or more and a specific resistance of 5 Ω ･ cm or more and 12000 Ω 无法 cm or less. The results are shown in Table 2.

(Comparative Example 5) A Sn-Zn-O-based oxide sintered body of Comparative Example 5 was obtained in the same manner as in Example 1 except that the sintering temperature was set to 1280 ° C. For the Sn-Zn-O-based oxide sintered body of Comparative Example 5, the results of X-ray diffraction analysis were performed in the same manner as in Example 1. The wurtzite-type ZnO phase was 34% and the spinel-type crystal structure was the same. The Zn ₂ SnO ₄ phase is 66% diffracted. No diffraction peak was measured for the other compound phases. As a result of measuring the relative density and specific resistance, the relative density was 91.0%, and the specific resistance was 14000 Ω ･ cm. That is, it was confirmed that it was impossible to achieve a relative density of 94% or more and a specific resistance of 5 Ω ･ cm or more and 12000 Ω 无法 cm or less. The results are shown in Table 2.

(Comparative Example 6) A Sn-Zn-O-based oxide sintered body of Comparative Example 6 was obtained in the same manner as in Example 1 except that the sintering temperature was set to 1,430 ° C in Comparative Example 6. For the Sn-Zn-O-based oxide sintered body of Comparative Example 6, the results of X-ray diffraction analysis were performed in the same manner as in Example 1. The wurtzite-type ZnO phase was 34% and the spinel-type crystal structure was The Zn ₂ SnO ₄ phase is 66% diffracted. No diffraction peak was measured for the other compound phases. As a result of measuring the relative density and specific resistance, the relative density was 93.0%, and the specific resistance was 12500 Ω ･ cm. That is, it was confirmed that it was impossible to achieve a relative density of 94% or more and a specific resistance of 5 Ω ･ cm or more and 12000 Ω 无法 cm or less. The results are shown in Table 2.

(Comparative Example 7) In Comparative Example 7, a Sn-Zn-O system of Comparative Example 7 was obtained in the same manner as in Example 1 except that the holding time of sintering at 1350 ° C was set to 10 hours. An oxide sintered body. The Sn-Zn-O-based oxide sintered body of Comparative Example 7 was subjected to X-ray diffraction analysis in the same manner as in Example 1. The wurtzite-type ZnO phase was 34% and the spinel-type crystal structure was the same. The Zn ₂ SnO ₄ phase is 66% diffracted. No diffraction peak was measured for the other compound phases. As a result of measuring the relative density and specific resistance value, the relative density was 90.0%, and the specific resistance value was 13,500 Ω ･ cm. That is, it was confirmed that it was impossible to achieve a relative density of 94% or more and a specific resistance of 5 Ω ･ cm or more and 12000 Ω 无法 cm or less. The results are shown in Table 2.

(Comparative Example 8) In Comparative Example 8, the Sn-Zn-O system of Comparative Example 8 was obtained in the same manner as in Example 1 except that the holding time of sintering at 1350 ° C was set to 30 hours. An oxide sintered body. For the Sn-Zn-O-based oxide sintered body of Comparative Example 8, the results of X-ray diffraction analysis were performed in the same manner as in Example 1. The wurtzite-type ZnO phase was 34% and the spinel-type crystal structure was the same. The Zn ₂ SnO ₄ phase is 66% diffracted. No diffraction peak was measured for the other compound phases. In addition, as a result of measuring the relative density and specific resistance value, there was volatilization of ZnO or Zn ₂ SnO ₄ , the relative density was 93.0%, and the specific resistance value was 13000 Ω ･ cm. That is, it was confirmed that it was impossible to achieve a relative density of 94% or more and a specific resistance of 5 Ω ･ cm or more and 12000 Ω 无法 cm or less. The results are shown in Table 2.

(Comparative Example 9) Comparative Example 9 was prepared in the same manner as in Example 1 except that Ge / (Sn + Zn + Ge + Ta + Ga) was adjusted to a ratio of 0.03, and Comparative Example 9 was obtained. Sn-Zn-O based oxide sintered body. For the Sn-Zn-O-based oxide sintered body of Comparative Example 9, the results of X-ray diffraction analysis were performed in the same manner as in Example 1. The wurtzite-type ZnO phase was 34% and the spinel-type crystal structure was the same. The Zn ₂ SnO ₄ phase is 66% diffracted. No diffraction peak was measured for the other compound phases. As a result of measuring the relative density and specific resistance, the relative density was 93.0%, and the specific resistance was 8500 Ω ･ cm. That is, it was confirmed that the relative density could not be achieved at 94% or more. The results are shown in Table 2.

(Comparative Example 10) Comparative Example 10 was prepared in the same manner as in Example 1 except that Ge / (Sn + Zn + Ge + Ta + Ga) became 0.0001, and Comparative Example 10 was obtained. Sn-Zn-O based oxide sintered body. For the Sn-Zn-O-based oxide sintered body of Comparative Example 10, the results of X-ray diffraction analysis were performed in the same manner as in Example 1. The wurtzite-type ZnO phase was 34% and the spinel-type crystal structure The Zn ₂ SnO ₄ phase is 66% diffracted. No diffraction peak was measured for the other compound phases. As a result of measuring the relative density and specific resistance, the relative density was 91.0%, and the specific resistance was 9800 Ω ･ cm. That is, it was confirmed that the relative density could not be achieved at 94% or more. The results are shown in Table 2.

(Comparative Example 11) Comparative Example 11 was prepared in the same manner as in Example 1 except that Ta / (Sn + Zn + Ge + Ta + Ga) was adjusted to a ratio of 0.03, and Comparative Example 11 was obtained. Sn-Zn-O based oxide sintered body. For the Sn-Zn-O-based oxide sintered body of Comparative Example 11, the results of X-ray diffraction analysis were performed in the same manner as in Example 1. The wurtzite-type ZnO phase was 34% and the spinel-type crystal structure The Zn ₂ SnO ₄ phase is 66% diffracted. No diffraction peak was measured for the other compound phases. As a result of measuring the relative density and specific resistance value, the relative density was 97.0%, and the specific resistance value was 16000 Ω ･ cm. That is, it was confirmed that the specific resistance could not be higher than 5 Ω ･ cm and lower than 12000 Ω ･ cm. The results are shown in Table 2.

(Comparative Example 12) Comparative Example 12 was prepared in the same manner as in Example 1 except that Ta / (Sn + Zn + Ge + Ta + Ga) was set to a ratio of 0.0001, and Comparative Example 12 was obtained. Sn-Zn-O based oxide sintered body. The Sn-Zn-O-based oxide sintered body of Comparative Example 12 was subjected to X-ray diffraction analysis in the same manner as in Example 1. The wurtzite-type ZnO phase was 34% and the spinel-type crystal structure was The Zn ₂ SnO ₄ phase is 66% diffracted. No diffraction peak was measured for the other compound phases. As a result of measuring the relative density and specific resistance value, the relative density was 96.7%, and the specific resistance value was 25000 Ω ･ cm. That is, it was confirmed that the specific resistance could not be higher than 5 Ω ･ cm and lower than 12000 Ω ･ cm. The results are shown in Table 2.

(Comparative Example 13) Comparative Example 13 was obtained in the same manner as in Example 1 except that Ga / (Sn + Zn + Ge + Ta + Ga) was set to a ratio of 0.2, and Comparative Example 13 was obtained. Sn-Zn-O based oxide sintered body. The Sn-Zn-O-based oxide sintered body of Comparative Example 13 was subjected to X-ray diffraction analysis in the same manner as in Example 1. The wurtzite-type ZnO phase was 34% and the spinel crystal structure The Zn ₂ SnO ₄ phase is 66% diffracted. No diffraction peak was measured for the other compound phases. As a result of measuring the relative density and specific resistance, the relative density was 97.3%, and the specific resistance was 14800 Ω ･ cm. That is, it was confirmed that the specific resistance could not be higher than 5 Ω ･ cm and lower than 12000 Ω ･ cm. The results are shown in Table 2.

(Comparative Example 14) Comparative Example 14 was prepared in the same manner as in Example 1 except that Ga / (Sn + Zn + Ge + Ta + Ga) was set to a ratio of 0.0008, and Comparative Example 14 was obtained. Sn-Zn-O based oxide sintered body. For the Sn-Zn-O-based oxide sintered body of Comparative Example 14, the results of X-ray diffraction analysis were performed in the same manner as in Example 1. The wurtzite-type ZnO phase was 34% and the spinel crystal structure The Zn ₂ SnO ₄ phase is 66% diffracted. No diffraction peak was measured for the other compound phases. As a result of measuring the relative density and specific resistance value, the relative density was 97.0%, and the specific resistance value was 22000 Ω ･ cm. That is, it was confirmed that the specific resistance could not be higher than 5 Ω ･ cm and lower than 12000 Ω ･ cm. The results are shown in Table 2.

In addition, as described above, one embodiment of the present invention and each embodiment have been described in detail, but those skilled in the art can easily understand that various modifications can be made without actually departing from the novel matters and effects of the present invention. Therefore, all such modifications are included in the scope of the present invention.

For example, in a description or a drawing, a term that is described at least once with a different term that is more broadly or synonymously is replaced with a different term anywhere in the description or the drawing. The structure of the Sn-Zn-O-based oxide sintered body and the method for producing the same are not limited to those described in one embodiment of the present invention and the examples, and various modifications can be made.

[Fig. 1] Fig. 1 is a schematic diagram showing a process of a method for producing a Sn-Zn-O-based oxide sintered body according to an embodiment of the present invention.

Claims (6)

A Sn-Zn-O-based oxide sintered body, which is a Sn-Zn-O-based oxide sintered body having zinc (Zn) and tin (Sn) as components, wherein ytterbium further contains at least germanium (Ge), Tantalum (Ta) and gallium (Ga) as components, the ratio of rhenium metal atomic ratio Sn / (Zn + Sn) is 0.1 or more and 0.3 or less, Ge / (Zn + Sn + Ge + Ta + Ga) is 0.0005 or more and 0.01 or less, Ta / (Zn + Sn + Ge + Ta + Ga) is 0.0005 or more and 0.01 or less, Ga / (Zn + Sn + Ge + Ta + Ga) is 0.001 or more and 0.1 or less, and specific resistance is 5Ω ･ cm or more and 12000Ω ･ cm or less. The relative density is above 94%. For example, the sintered body of Sn-Zn-O oxide according to claim 1, wherein the metal atomic ratio Sn / (Zn + Sn) is 0.16 or more and 0.23 or less, and the specific resistance is 5Ω ･ cm or more and 110Ω ･ cm or less, The aforementioned relative density is 98% or more. For example, the Sn-Zn-O-based oxide sintered body according to claim 1, wherein the ZnO phase having a wurtzite type crystal structure is in a range of 5 to 70% of the whole, or Zn ₂ SnO _{4 having a} spinel type crystal structure. The phase is constituted by a range of 30 to 95% of the whole. For example, the Sn-Zn-O-based oxide sintered body according to claim 2, wherein the ZnO phase with a wurtzite-type crystal structure is in a range of 5 to 70% of the whole, or Zn ₂ SnO _{4 with a} spinel-type crystal structure. The phase is constituted by a range of 30 to 95% of the whole. A method for manufacturing a Sn-Zn-O-based oxide sintered body, which is a method for manufacturing a Sn-Zn-O-based oxide sintered body having zinc (Zn) and tin (Sn) as components, which is characterized by having the following steps : A granulation step of preparing a granulated powder by mixing zinc oxide powder, tin oxide powder, and an oxide powder containing an additive element; press-forming the granulated powder to obtain a molded body A forming step; and a firing step of firing the formed body to obtain an oxide sintered body, the aforementioned additive element is at least germanium (Ge), tantalum (Ta), and gallium (Ga), and so that the metal atomic ratio is Sn / (Zn + Sn) is 0.1 or more and 0.3 or less, Ge / (Zn + Sn + Ge + Ta + Ga) is 0.0005 or more and 0.01 or less, Ta / (Zn + Sn + Ge + Ta + Ga) is 0.0005 or more and 0.01 Hereinafter, the zinc oxide powder, the tin oxide powder, and the additive element-containing oxide powder are mixed so that Ga / (Zn + Sn + Ge + Ta + Ga) is 0.001 or more and 0.1 or less. For example, the method for producing a Sn-Zn-O-based oxide sintered body according to claim 5, wherein the temperature in the firing furnace is in the atmosphere of a firing furnace in the aforementioned firing step, and the temperature is raised at a rate of 0.3 to 1.0 ° C / min. The molded body is fired to a temperature of 1300 ° C or higher and 1400 ° C or lower and within 15 hours to 25 hours.