TWI741154B - Sn-Zn-O series oxide sintered body and its manufacturing method - Google Patents

Abstract

The present invention provides a high-density and low-resistance Sn-Zn-O-based oxide sintered body that can be used in applications such as barrier films or protective films, and a method for manufacturing the same. The Sn-Zn-O-based oxide sintered system of the present invention has zinc (Zn) and tin (Sn) as the components of the Sn-Zn-O-based oxide sintered body, which further contains at least germanium (Ge), tantalum (Ta ), and gallium (Ga) as components, and the metal atom number 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 to 0.01, Ga/(Zn+Sn+Ge+Ta+Ga) is 0.001 to 0.1, specific resistance is 5Ω･cm to 12000Ω･cm, relative density It is more than 94%.

Description

Sn-Zn-O series oxide sintered body and its manufacturing method

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

Transparent conductive films with high conductivity and high transmittance in the visible light region are used in solar cells, liquid crystal display devices, organic electroluminescence, inorganic electroluminescence, and other surface elements, or touch panel electrodes, 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 for automobile windows or construction.

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 containing tin as a dopant ( In ₂ O ₃ ) and so on. In particular, an indium oxide (In ₂ O ₃ ) film containing tin as a dopant, that is, an In-Sn-O film system is called an ITO (Indium tin oxide) film, because it is easy to obtain a low-resistance film , And is widely used.

As the manufacturing method of the above-mentioned transparent conductive film, the sputtering method of direct current sputtering and high frequency sputtering is often used. When it is necessary to form a film of a material with a low vapor pressure or to control a precise film thickness, the sputtering method is an effective method. Since the operation is very simple, it is widely used industrially.

In order to manufacture the above-mentioned transparent conductive film, conventionally, indium oxide-based materials such as ITO have been widely used. However, indium metal is a rare metal on the earth and is toxic. Therefore, there is a concern about adverse effects on the environment or the human body, and non-indium-based materials are required.

As the aforementioned non-indium-based materials, as described above, zinc oxide (ZnO)-based materials containing aluminum or gallium as a dopant, and tin oxide (SnO ₂ )-based materials 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 the sputtering method, but it has disadvantages such as lack of chemical resistance (alkali resistance and acid resistance). On the other hand, _{although the transparent conductive film of tin oxide (SnO 2} )-based materials is excellent in chemical resistance, it is difficult to produce high-density and durable tin oxide-based sintered target materials. Therefore, it is difficult to use sputtering. Method to manufacture the above-mentioned shortcomings of the transparent conductive film.

Therefore, as a material to improve these shortcomings, a sintered body containing 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 crystal phase of tin oxide or a crystal phase of tin oxide in which zinc is dissolved, but a zinc oxide phase and tin oxide phase It is composed of zinc acid compound phase or zinc stannate compound phase.

Further, in Patent Document 2 describes a sintered body based average grain size of 4.5μm or less, and when using CuKα rays have an X-ray diffraction of Zn (222) ₂ SnO ₄ phase plane, ( When the cumulative intensity of 400) surface is set to I ₍₂₂₂₎ and I ₍₄₀₀₎ , the _{orientation degree expressed by I (222)} /[I ₍₂₂₂₎ +I ₍₄₀₀₎ ] is greater than the standard (0.44) 0.52 or more. Furthermore, Patent Document 2 also describes as a method of manufacturing a sintered body having the above-mentioned characteristics, a method of constructing a manufacturing step of the sintered body by the following steps: In the environment, the step of sintering the molded body under the condition of 800℃～1400℃; and after the holding at the highest sintering temperature, the inside of the sintering furnace is cooled by an inert environment such as Ar gas step. [Prior Technical Documents] [Patent Documents]

[Patent Document 1] Japanese Patent Application Publication No. 2007-277075 　　 [Patent Document 2] Japanese Patent Application Publication No. 2013-036073

[The problem to be solved by the invention]

However, in these methods, in the Sn-Zn-O-based oxide sintered body with Zn and Sn as the main components, although the strength of the sintered body that can withstand mechanical strength can be obtained, it is difficult to obtain sufficient density or electrical conductivity. As a characteristic required for sputtering film formation at the mass production site, it cannot be satisfied. That is, in the normal pressure sintering method, there are still problems in achieving high density or electrical conductivity of the sintered body.

The Sn-Zn-O series oxide sintered body with Zn and Sn as the main components is made of materials that are difficult to have the characteristics of high density and low resistance. Even if the blending ratio of Sn and Zn is changed, it is difficult to produce high density and An oxide sintered body with excellent conductivity. In the density of the sintered body, although there is a slight fluctuation in the density due to the blending ratio, the conductivity shows a ^{very high specific resistance value of 1×10 6} Ω･cm or more, and the conductivity is lacking.

In the production of Sn-Zn-O based oxide sintered body with Zn and Sn as the main components, Zn ₂ SnO ₄ compounds are formed from around 1100°C, and Zn volatilization starts at around 1400°C, starting at around 1450°C The volatilization of Zn becomes obvious. If the Sn-Zn-O-based oxide sintered body is fired at a high temperature in order to increase the density, the volatilization of Zn progresses, so the grain boundary diffusion or the bond between the grains is weak, and high-density oxide sintering cannot be obtained. body.

In addition, regarding conductivity, Zn ₂ SnO ₄ , ZnO, and SnO ₂ are poor in conductivity. Therefore, even if the blending ratio is adjusted to adjust the compound phase or _{the amount of ZnO and SnO 2} , the conductivity cannot be greatly improved.

The sintered body of ITO used in the past has a specific resistance value of 2 to 3×10 ^-4 Ω･cm. By sputtering the sintered body as a target, it is suitable for use as a transparent conductive film for liquid crystals, solar cells, etc. . On the other hand, in recent years, there have been applications in which the conductivity is worse than ITO, but can be used for gas barrier films, water vapor barrier films, and other barrier films or protective films for protection 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, the subject of the present invention is to provide a high-density and low-resistance Sn-Zn-O-based oxide sintered body that can be used in applications such as barrier films or protective films, and a method of manufacturing the same. [Means to solve the problem]

The inventors of the present invention have found that in order to solve the above-mentioned problems, Sn is contained in a ratio of Sn/(Sn+Zn) of 0.1 or more and 0.3 or less as the atomic ratio, and Ge, Ta, and Ga are contained in a specific ratio as an additive element. There are three types, and a high-density Sn-Zn-O oxide sintered body with a specific resistance value of about 10Ω･cm～×10 ^{4 Ω･cm suitable for barrier films or protective films can be obtained, thus completing this} invention.

That is, the same state of the present invention is a Sn-Zn-O-based oxide sintered body having zinc (Zn) and tin (Sn) as components, which further contains at least germanium (Ge), tantalum (Ta), and gallium (Ga) as a component, and the metal atom number ratio is Sn/(Zn+Sn) 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, specific resistance is 5Ω･cm or more and 12000Ω･cm or less, relative density is 94% or more .

According to the same aspect of the present invention, by making Sn/(Sn+Zn) a ratio of 0.1 or more and 0.3 or less, and using three kinds of germanium (Ge), tantalum (Ta), and gallium (Ga) as additional elements, Instead, it can be used as a high-density and low-resistance Sn-Zn-O-based oxide sintered body that can be used in applications such as barrier films and protective films.

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

In this way, by further limiting Sn/(Zn+Sn), a Sn-Zn-O-based oxide sintered body with high density and low resistance can be further realized.

In addition, in the same aspect of the present invention, in the Sn-Zn-O-based oxide sintered body, the ZnO phase that can be set as a wurtzite-type crystal structure is 5 to 70% of the total (in this specification, "~ It is set to mean the range above the lower limit and below the upper limit, the same below), or the Zn ₂ SnO ₄ phase of the spinel crystal structure is constituted in the 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 composed of the above-mentioned crystal structure is obtained.

In addition, another aspect of the present invention is a method for manufacturing a Sn-Zn-O-based oxide sintered body having zinc (Zn) and tin (Sn) as components, which includes the following steps: A granulation process of mixing the oxide powder and the oxide powder containing the added element to produce a granulated powder; a molding step of press-forming the granulated powder to obtain a molded body; and firing the molded body In the firing step to obtain the oxide sintered body, the aforementioned additional elements are at least germanium (Ge), tantalum (Ta), and gallium (Ga), so that the ratio of metal atoms is Sn/(Zn+Sn) of 0.1 or more and 0.3 Below, Ge/(Zn+Sn+Ge+Ta+Ga) is above 0.0005 and below 0.01, Ta/(Zn+Sn+Ge+Ta+Ga) is above 0.0005 and below 0.01, 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 oxide powder containing the additive element.

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

At this time, in another aspect of the present invention, it is preferable to raise the temperature in the firing step in the atmosphere of the firing furnace at a rate of temperature rise of 0.3-1.0°C/min to 1300°C or more and 1400°C or less , 15 hours to 25 hours, to sinter the aforementioned molded body.

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 manufactured. [Effects of the invention]

According to the present invention, a high-density and low-resistance Sn-Zn-O-based oxide sintered body can be used for applications such as barrier films or protective films.

Hereinafter, the Sn-Zn-O-based oxide sintered body of the present invention and its manufacturing method will be described in the following order with reference to the drawings. In addition, 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. Manufacturing method of Sn-Zn-O-based oxide sintered body 　　　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 sintered system of one embodiment of the present invention contains Sn as an atomic ratio Sn/(Sn+Zn) of 0.1 to 0.3 in proportion to the total amount of all metal elements. The atomic number ratio Ge/(Sn+Zn+Ge+Ta+ Ga) is 0.0005 or more and 0.01 or less, and the first additional element Ge is included, and the atomic number ratio Ta/(Sn+Zn +Ge +Ta+Ga) is 0.0005 or more and 0.01 or less, containing the second additional element Ta, and the atomic ratio Ga/(Sn+Zn+Ge+Ta+Ga) relative to the total amount of all metal elements is The third additive element Ga is contained in a ratio of 0.001 or more and 0.1 or less. In this way, the Sn-Zn-O-based oxide sintered system of one embodiment of the present invention has a specific resistance of 5Ω･cm or more and 12000Ω･cm or less, and a relative density of 94% or more.

The tin oxide and zinc oxide as the main raw materials of the Sn-Zn-O based oxide sintered body of one embodiment of the present invention will only be zinc oxide tin compounds, or raw material powders containing mixed powders of tin oxide and zinc oxide , Sn is contained in a ratio of Sn/(Sn+Zn) of 0.1 to 0.3 as the atomic ratio.

Due to the Sn content, a difference is observed in the crystal structure of the sintered body after sintering. When Sn is contained in a ratio of Sn/(Sn+Zn) of 0.1 to 0.3 as the atomic ratio, the ZnO phase of the wurtzite crystal structure and the Zn ₂ SnO ₄ phase of the spinel crystal structure are 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. If the main component of the SnO ₂ phase of the rutile crystal structure increases, the resistance value increases. In addition, the transmittance will also decrease.

The atomic ratio Sn/(Sn+Zn) is more preferably 0.16 or more and 0.23 or less. If it is in this range, it will become a desired resistance value, and it will become 98% or more with respect to density, and it is more preferable.

In the production of Sn-Zn-O-based oxide sintered bodies, as mentioned above, during sintering, Zn ₂ SnO ₄ compounds start to be generated from around 1100°C, volatilization of Zn starts after 1400°C, and Zn starts at around 1450°C. The volatilization becomes obvious. If the Sn-Zn-O-based oxide sintered body is fired at a high temperature in order to increase the density, the volatilization of Zn progresses, so the grain boundary diffusion or the bond between the grains is weak, and high-density oxide sintering cannot be obtained. body. On the other hand, with regard to conductivity, Zn ₂ SnO ₄ , ZnO, and SnO ₂ are materials that lack conductivity. Therefore, even if the blending ratio is adjusted to adjust the compound phase or _{the amount of ZnO and SnO 2} , the conductivity cannot be greatly improved. improve.

(Additional element) ”Therefore, in the present invention, the first to third additional elements are added in order to improve the above-mentioned conductivity. That is, by adding germanium (Ge) as the first additional element, tantalum (Ta) as the second additional element, and gallium (Ga) as the third additional element, it becomes possible to obtain Sn-Zn with high density and low resistance. -O-based oxide sintered body.

[First additional element] In order to densify the oxide sintered body, the addition of Ge as the first additional element has the effect of obtaining a higher density. The first additive element Ge promotes the diffusion of grain boundaries and helps the growth of crystal necks between grains, so that the bonds between grains become strong and contribute to densification. Here, the reason why the atomic ratio Ge/(Sn+Zn+Ge+Ta+Ga) of the first additive element Ge to the total amount of all metal elements is set to 0.0005 or more and 0.01 or less is that the above-mentioned atomic number ratio Ge When / (Sn+Zn+Ge+Ta+Ga) is less than 0.0005, the effect of increasing the density cannot be exhibited (see Comparative Example 10). When the atomic ratio Ge/(Sn+Zn+Ge+Ta+Ga) exceeds 0.01, the effect of increasing the density cannot be exhibited (see Comparative Example 9). And it will generate other compounds, such as Zn ₂ Ge ₃ O ₈ compounds.

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

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

Therefore, the second additional element Ta is added. With the addition of the second additional element Ta, the conductivity is improved while maintaining the high density of the oxide sintered body. In addition, the second additional element Ta is an element with a valence of 5 or higher.

The amount of addition must be such that the atomic ratio Ta/(Sn+Zn+Ge+Ta+Ga) of the second additional element Ta to the total amount of all metal elements 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 above-mentioned atomic ratio Ta/(Sn+Zn+Ge+Ta+Ga) exceeds 0.01, other compound phases such as Ta ₂ O ₅ , ZnTa ₂ O ₆ and the like will be formed. , Therefore, the conductivity deteriorates (see Comparative Example 11).

[Third additional element] As described above, the conductivity is improved by the addition of the second additional element Ta. However, Ta will replace with Sn and SnO _{2 in the Zn 2} SnO ₄ phase to be solid-soluted. Therefore, the conductivity of the desired resistance value may not be obtained in some cases.

Therefore, the third additional element Ga is added. The addition of the third additive element Ga is expected to improve the conductivity of Zn in _{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 additional element Ge to the total amount of all metal elements is 0.001 or more and 0.1 or less. In the case where 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 Ga ₂ O _3, etc. will be formed, which will lead to electrical conductivity. Sexual deterioration (refer to Comparative Example 13).

In addition, as long as it does not impair the characteristics of the Sn-Zn-O-based oxide sintered body as one of the embodiments of the present invention, it can be used in applications such as barrier films or protective films, with high density (relative density of 94% or more) and Those with a low resistance (specific resistance of 5Ω･cm or more and 12000Ω･cm or less) may further contain additional elements. 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 oxide sintered body of one embodiment of the present invention, when the atomic ratio Sn/(Sn+Zn) is 0.1 or more and 0.3 or less, the wurtzite type crystal The ZnO phase of the structure and the Zn ₂ SnO ₄ phase of the spinel crystal structure are the main components. In addition, the appropriate amount of the first additive element Ge, the second additive element Ta, and the third additive element Ga will be combined with the Zn in the ZnO phase. , Zn in the Zn ₂ SnO ₄ phase or Sn in the SnO ₂ phase is replaced by Sn in the SnO 2 phase for solid solution. Therefore, the ZnO phase of the wurtzite crystal structure and the Zn ₂ SnO ₄ phase of the spinel crystal structure are other than Other compound phases will not be formed.

(Resistivity) The specific resistance of the Sn-Zn-O-based oxide sintered body according to one 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 Sn-Zn-O oxide sintered body has conventionally been a very high specific resistance value of ^{1×10 6 Ω･cm or more.} In the present invention, the specific resistance value is lowered by blending Ge, Ta, and Ga as the first to third additional elements.

The sintered body of ITO used in the past has a specific resistance value of 2～3×10 ^-4 Ω･cm. By sputtering this sintered body as a target, it is suitable for use as a transparent conductive film for liquid crystal or solar electronics. . The specific resistance of the transparent conductive film obtained by sputtering the Sn-Zn-O based oxide sintered body of one embodiment of the present invention is about 10Ω･cm to 1×10 ⁴ Ω･cm. Therefore, the conductivity is It is inferior to ITO, but it can be used for gas barrier films, water vapor barrier films and other barrier films or protective films for protection from damage or impact. The Sn-Zn-O oxide sintered system of one embodiment of the present invention is suitable for sputtering specific resistance of films with a ^{specific resistance of about 10Ω･cm to 1×10 4 Ω･cm.}

The specific resistance value of the sputtered film will also be affected by the film forming conditions during the sputtering, especially the oxygen concentration during the sputtering. However, if considering the productivity during sputtering, the uniformity of the film, etc., it is better that the specific resistance value of the film is consistent with the specific resistance value of the crystal.

In addition, the specific resistance value depends on the film formation speed during sputtering. Therefore, the smaller the specific resistance value, the better. The Sn-Zn-O-based oxide sintered body according to one embodiment of the present invention has a specific resistance of 5Ω･cm or more and 12000Ω･cm or less, and therefore becomes an oxide sintered body suitable for sputtering. In the case where the specific resistance is less than 5Ω･cm, the resistance value of the resulting film will become low, so leakage from nearby electrodes becomes a problem. In addition, if the specific resistance value exceeds 12000 Ω·cm, it becomes difficult to discharge, and the film cannot be formed stably with respect to DC sputtering, which becomes a problem.

Furthermore, in one embodiment of the present invention, by making the ratio of the number of metal atoms of Sn/(Zn+Sn) 0.16 or more and 0.23 or less, the specific resistance value can be set in the range of 5Ω･cm or more and 110Ω･cm or less. (Refer to Examples 1, 8, 9). It is better to increase the film forming speed by making the specific resistance value 5Ω･cm or more and 110Ω･cm or less.

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

In addition, by making the metal atom number ratio Sn/(Zn+Sn) 0.16 or more and 0.23 or less, the aforementioned relative density can be increased to 98% or more. When the relative density is 98% or more, the strength of the target material increases and the film formation speed during sputtering increases. At the same time, the outgassing due to the target material decreases, resulting in 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 manufacturing a Sn-Zn-O-based oxide sintered body having zinc (Zn) and tin (Sn) as components, which includes the following steps: oxidizing zinc oxide powder and tin The granulation step S1 of mixing the powder and the oxide powder containing the additive element to produce a granulated powder; the molding step S2 of press-forming the granulated powder to obtain a molded body; and firing the molded body Then, the firing step S3 of the oxide sintered body is obtained. For example, the Sn-Zn-O-based oxide sintering system of one embodiment of the present invention is a raw material powder containing only a zinc tin oxide compound or a mixed powder of tin oxide and zinc oxide, and the second is blended at a specific ratio 1. The germanium oxide of the additional element, the tantalum oxide of the second additional element, and the gallium oxide of the third additional element are granulated, and the granulated powder is formed by cold equalizing pressure, etc., and the formed body is fired in a sintering furnace To obtain a sintered body. Hereinafter, each step will be described individually.

(2-1. Granulation step) First, in the granulation step S1, the main raw material is prepared. The main raw materials of tin oxide and zinc oxide are only zinc oxide tin compounds, or raw material powders containing mixed powder of tin oxide and zinc oxide, as the atomic ratio Sn/ (Sn+Zn) is 0.1 or more and 0.3 or less The ratio contains Sn. If the main raw material is mixed powder of tin oxide and zinc oxide, it is easier to adjust the blending ratio, which is better. For example, the raw material powder is SnO ₂ powder and ZnO powder. In addition, an oxide containing the first additional element to the third additional element is prepared, and is added to this main raw material for blending. _{For example, GeO 2} powder as the first additive element Ge _{, Ta 2} O ₅ powder as the second additive element Ta, and _{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 atom number ratio is 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 to combine zinc oxide powder, tin oxide powder, and The oxide powders containing added elements are mixed. In this way, so that the ratio of Sn/(Zn+Sn) is 0.1 or more and 0.3 or less, and as described above, three kinds of germanium (Ge), tantalum (Ta), and gallium (Ga) are specified as additional elements. By mixing in a proportion, it is possible to produce a high-density and low-resistance Sn-Zn-O-based oxide sintered body that can be used in applications such as barrier films and protective films.

Next, the prepared raw material powder, pure water or ultrapure water, organic binder, dispersant, and defoamer are mixed in a mixing tank so that the concentration of the raw material powder becomes a specific concentration. In addition, using _{a bead mill or the like in which hard ZrO 2} balls are introduced, the raw material powder is wet-pulverized, and then mixed and stirred to obtain a slurry. By spraying and drying the obtained slurry with a spray drying device or the like, granulated powder can be obtained.

(2-2. Forming step) The forming step S2 is a step of press-forming the granulated powder obtained in the granulating step S1 to obtain a molded body. In the forming step S2, in order to remove the 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 there is no particular limitation on the method of press molding, for example, it is preferable to fill the granulated powder obtained in the granulation step S1 in a rubber mold and use a cold isostatic press (CIP: Cold Isostatic Press) that can apply high pressure. .

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

[Rate of temperature rise] The rate of temperature rise from 700°C to a specific sintering temperature in the sintering furnace is preferably at a rate of 0.3 to 1.0°C/min to sinter the molded body. It has the effect of promoting _{the diffusion of ZnO, SnO 2} or Zn ₂ SnO ₄ compounds, improving sinterability, and improving conductivity. In addition, by setting such a heating rate, it also has the effect of _{suppressing the volatilization of ZnO or Zn 2} SnO _{4 in the high temperature range.}

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

When the heating rate in the sintering furnace is less than 0.3°C/min, the diffusion of the compound will decline. In addition, if it exceeds 1.0° C./min, since the rate of temperature rise is rapid, compound formation may be incomplete, and a dense sintered body cannot be produced. (Refer to Comparative Examples 3 and 4).

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

[Holding time] The holding time is preferably set to 15 hours or more and within 25 hours. If it is less than 15 hours, the sintering will be incomplete, so it becomes a sintered body with large deformation or warpage, and grain boundary diffusion does not proceed, and sintering does not proceed. As a result, a dense sintered body could not be produced (see Comparative Example 7). On the other hand, if it exceeds 25 hours, _{the volatilization of ZnO or Zn 2} SnO ₄ will increase, resulting in a decrease in density, deterioration of work efficiency, and high cost (see Comparative Example 8).

The Sn-Zn-O-based oxide sintered body of one embodiment of the present invention having Zn and Sn as main components obtained under such conditions also has improved conductivity, and therefore becomes a film that can be formed by DC sputtering. In addition, since no special manufacturing method is used, it can also be applied to cylindrical targets. [Example]

Hereinafter, the present invention will be explained in more detail using examples, but the present invention is not limited at all by the following examples.

(Example 1) In Example 1, SnO ₂ powder, ZnO powder, GeO _{2 powder as the first additional element Ge, Ta 2} O ₅ powder as the second additional element Ta, and Ga as the third additional element were prepared The Ga ₂ O ₃ powder.

_{Next, SnO 2} powder and ZnO powder are blended so that the atomic ratio of Sn to Zn Sn/(Sn+Zn) becomes 0.2, so that the atomic ratio of the first additional element Ge is Ge/(Sn+Zn+Ge +Ta+Ga) becomes 0.004, the atomic ratio Ta/(Sn+Zn+Ge+Ta+Ga) of the second additional element Ta is 0.002, and the atomic ratio of the third additional element Ga Ga/((Sn +Zn+Ge+Ta+Ga) becomes 0.02 to prepare GeO ₂ powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder.

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

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

Then, the obtained granulated powder was filled in a rubber mold, and a pressure of 294 MPa (3 ton/cm ² ) was applied by cold equalization to form. The obtained formed body with a diameter of about 250 mm was put into an atmospheric sintering furnace and placed in the sintering furnace. Introduce air to 700°C. After confirming that the temperature in the firing furnace became 700°C, oxygen was introduced, the temperature was raised to 1350°C, and the temperature was maintained at 1350°C for 20 hours. The heating rate at this time is set to 0.7°C/min.

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

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 (GRINDING CENTER).

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

In addition, a part of the processed body was cut and crushed with a mortar to form a powder. For this powder, the result of analysis using an X-ray diffraction device [X'Pert-PRO (manufactured by PANalytical)] with CuKα rays showed that the spinel crystal structure of the Zn ₂ SnO ₄ phase is 66% and wurtzite The ZnO phase of the mineral crystal structure is 34% diffraction of the whole, and the diffraction peaks of other compound phases are not measured. The results are shown in Table 1.

(Example 2) In Example 2, the Sn and Zn atomic ratio Sn/(Sn+Zn) was prepared at a ratio of 0.1, except that the same method as in Example 1 was used to obtain an example 2 Sn-Zn-O series oxide sintered body. In the same manner as in Example 1, the powder X-ray diffraction analysis showed that 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 peaks of other compound phases were measured. In addition, the relative density is 96.0%, and the specific resistance value is 1780Ω･cm. The results are shown in Table 1.

(Example 3) In Example 3, the atomic ratio of Sn to Zn, Sn/(Sn+Zn), was blended at a ratio of 0.3, except that the same method as Example 1 was used to obtain an example 3 Sn-Zn-O series oxide sintered body. In the same manner as in Example 1, as a result of X-ray diffraction analysis of the powder, the wurtzite-type ZnO phase is 5%, and the spinel-type crystalline structure of the Zn ₂ SnO ₄ phase is 95% diffraction. No diffraction peaks of other compound phases were measured. In addition, the relative density is 95.5%, and the specific resistance value is 7100Ω･cm. The results are shown in Table 1.

(Example 4) In Example 4, the ratio of the atomic number of Sn to Zn, Sn/(Sn+Zn) was 0.1, so that the atomic ratio of the first additional element Ge was Ge/(Sn+Zn). +Ge+Ta+Ga) becomes 0.0005, the atomic number ratio Ta/(Sn+Zn+Ge+Ta+Ga) of the second additional element Ta is 0.0005, and the atomic number ratio of the third additional element Ga Ga/( _{GeO 2} powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder were prepared so that Sn+Zn+Ge+Ta+Ga) became 0.001, except that the same method as in Example 1 was used to obtain an example 4 Sn-Zn-O series oxide sintered body. As in Example 2, the wurtzite type ZnO phase is 70%, and the spinel crystal structure of the Zn ₂ SnO ₄ phase is 30% diffraction. No diffraction peaks of other compound phases were measured. In addition, the relative density is 95.0%, and the specific resistance value is 5300Ω･cm. The results are shown in Table 1.

(Example 5) In Example 5, the ratio of the atomic number of Sn to Zn, Sn/(Sn+Zn) was 0.1, so that the atomic ratio of the first additional element Ge was Ge/(Sn+Zn). +Ge+Ta+Ga) is set to 0.01, the atomic number ratio Ta/(Sn+Zn+Ge+Ta+Ga) of the second additional element Ta is set to 0.01, and the atomic number ratio of the third additional element Ga Ga/( _{GeO 2} powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder were prepared so that Sn+Zn+Ge+Ta+Ga) became 0.1, except that the same method as in Example 1 was used to obtain an example 5 Sn-Zn-O series oxide sintered body. As in Example 2, the wurtzite type ZnO phase is 70%, and the spinel crystal structure of the Zn ₂ SnO ₄ phase is 30% diffraction. No diffraction peaks of other compound phases were measured. In addition, the relative density is 96.0%, and the specific resistance value is 980Ω･cm. The results are shown in Table 1.

(Example 6) In Example 6, the atomic ratio of Sn to Zn, Sn/(Sn+Zn) was 0.3, so that the atomic ratio of Ge as the first additional element Ge/(Sn+Zn) +Ge+Ta+Ga) becomes 0.0005, the atomic number ratio Ta/(Sn+Zn+Ge+Ta+Ga) of the second additional element Ta is 0.0005, and the atomic number ratio of the third additional element Ga Ga/( _{GeO 2} powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder were prepared so that Sn+Zn+Ge+Ta+Ga) became 0.001, except that the same method as in Example 1 was used to obtain an example 6 Sn-Zn-O series oxide sintered body. As in Example 3, the wurtzite type ZnO phase is 5%, and the spinel type crystal structure of the Zn ₂ SnO ₄ phase is 95% diffraction. No diffraction peaks of other compound phases were measured. In addition, the relative density is 94.7%, and the specific resistance value is 10000Ω･cm. The results are shown in Table 1.

(Example 7) In Example 7, the atomic ratio of Sn to Zn, Sn/(Sn+Zn) was 0.3, so that the atomic ratio of Ge/(Sn+Zn) +Ge+Ta+Ga) is set to 0.01, the atomic number ratio Ta/(Sn+Zn+Ge+Ta+Ga) of the second additional element Ta is set to 0.01, and the atomic number ratio of the third additional element Ga Ga/( _{GeO 2} powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder were prepared so that Sn+Zn+Ge+Ta+Ga) became 0.1, except that the same method as in Example 1 was used to obtain an example 7 Sn-Zn-O series oxide sintered body. As in Example 3, the wurtzite type ZnO phase is 5%, and the spinel type crystal structure of the Zn ₂ SnO ₄ phase is 95% diffraction. No diffraction peaks of other compound phases were measured. In addition, the relative density is 95.0%, and the specific resistance value is 9500Ω･cm. The results are shown in Table 1.

(Example 8) In Example 8, the atomic ratio of Sn to Zn, Sn/(Sn+Zn), was blended at a ratio of 0.16, and the sintering holding temperature was set to 1300°C. In the same manner as in Example 1, the Sn-Zn-O-based oxide sintered body of Example 8 was obtained. In the same manner as in Example 1, the powder X-ray diffraction analysis showed that the Zn ₂ SnO ₄ phase of the spinel crystal structure was 54%, and the ZnO phase of the wurtzite crystal structure was 46% of the total winding. No diffraction peaks of other compound phases were measured. In addition, the relative density is 98.0%, and the specific resistance value is 60Ω･cm. The results are shown in Table 1.

(Example 9) In Example 9, the atomic ratio of Sn to Zn, Sn/(Sn+Zn), was blended at a ratio of 0.23, and the sintering holding temperature was set to 1400°C. In the same manner as in Example 1, the Sn-Zn-O-based oxide sintered body of Example 9 was obtained. In the same manner as in Example 1, the powder X-ray diffraction analysis showed that 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 total winding. No diffraction peaks of other compound phases were measured. In addition, the relative density is 98.5%, and the specific resistance value is 105Ω･cm. The results are shown in Table 1.

(Example 10) In Example 10, the ratio of the atomic number of Sn to Zn, Sn/(Sn+Zn) was 0.3, so that the atomic ratio of the first additional element Ge was Ge/(Sn+Zn). +Ge+Ta+Ga) becomes 0.0005, the atomic number ratio Ta/(Sn+Zn+Ge+Ta+Ga) of the second additional element Ta is 0.0005, and the atomic number ratio of the third additional element Ga Ga/( _{GeO 2} powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder were prepared so that Sn+Zn+Ge+Ta+Ga) became 0.001, and the sintering retention time was 15 hours. In addition, the same as in Example 1 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 is 5%, and the spinel crystal structure of the Zn ₂ SnO ₄ phase is 95% diffraction. No diffraction peaks of other compound phases were measured. In addition, the relative density is 94.0%, and the specific resistance value is 12000Ω･cm. The results are shown in Table 1.

(Example 11) In Example 11, the ratio of the atomic number of Sn to Zn, Sn/(Sn+Zn) was 0.3, so that the atomic ratio of the first additional element Ge was Ge/(Sn+Zn). +Ge+Ta+Ga) is set to 0.01, the atomic number ratio Ta/(Sn+Zn+Ge+Ta+Ga) of the second additional element Ta is set to 0.01, and the atomic number ratio of the third additional element Ga Ga/( _{GeO 2} powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder were prepared so that Sn+Zn+Ge+Ta+Ga) became 0.1, and the sintering retention time was 25 hours. In addition, the same as in Example 1 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 is 5%, and the spinel type crystal structure of the Zn ₂ SnO ₄ phase is 95% diffraction. No diffraction peaks of other compound phases were measured. In addition, the relative density is 95.5%, and the specific resistance value is 10500Ω･cm. The results are shown in Table 1.

(Example 12) In Example 12, the ratio of the atomic number of Sn to Zn, Sn/(Sn+Zn) was 0.1, so that the atomic ratio of the first additional element Ge was Ge/(Sn+Zn). +Ge+Ta+Ga) is set to 0.01, the atomic number ratio Ta/(Sn+Zn+Ge+Ta+Ga) of the second additional element Ta is set to 0.01, and the atomic number ratio of the third additional element Ga Ga/( Sn+Zn+Ge+Ta+Ga) becomes 0.1 to prepare GeO ₂ powder, Ta ₂ O ₅ powder, and Ga ₂ O ₃ powder, and set the heating rate to 0.3°C/min. In the same manner as in Example 1, the Sn-Zn-O-based oxide sintered body of Example 12 was obtained. As in Example 2, the wurtzite type ZnO phase is 70%, and the spinel crystal structure of the Zn ₂ SnO ₄ phase is 30% diffraction. No diffraction peaks of other compound phases were measured. In addition, the relative density is 95.0%, and the specific resistance value is 1320Ω･cm. The results are shown in Table 1.

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

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

(Comparative Example 2) In Comparative Example 2, the ratio of the atomic number of Sn to Zn, Sn/(Sn+Zn) was 0.40, and except that the ratio was prepared in the same manner as in Example 1, a comparative example was obtained. 2 Sn-Zn-O series oxide sintered body. For the Sn-Zn-O-based oxide sintered body of Comparative Example 2, the results of X-ray diffraction analysis in the same manner as in Example 1 showed that the wurtzite-type ZnO phase was 0% and the rutile-type SnO ₂ phase was 14 %, and the spinel crystal structure of Zn ₂ SnO ₄ phase is 86% diffraction. No diffraction peaks of other compound phases were measured. In addition, as a result of measuring the relative density and the specific resistance value, the relative density was 89.0%, and the specific resistance value was 597000Ω･cm. That is, it was confirmed that a relative density of 94% or more and a specific resistance of 5Ω･cm or more and 12000Ω･cm or less could not be achieved. The results are shown in Table 2.

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

(Comparative Example 4) In Comparative Example 4, except that the temperature increase rate was set to 1.2°C/min, the Sn-Zn-O-based oxide sintered body of Comparative Example 4 was obtained in the same manner as in Example 1 . With regard to the Sn-Zn-O-based oxide sintered body of Comparative Example 4, the result of X-ray diffraction analysis performed in the same manner as in Example 1 showed that the wurtzite-type ZnO phase is 34%, and the spinel-type crystal structure is The Zn ₂ SnO ₄ phase is 66% diffraction. No diffraction peaks of other compound phases were measured. In addition, as a result of measuring the relative density and the specific resistance value, the relative density was 92.0%, and the specific resistance value was 12500Ω･cm. That is, it was confirmed that a relative density of 94% or more and a specific resistance of 5Ω･cm or more and 12000Ω･cm or less could not be achieved. The results are shown in Table 2.

(Comparative Example 5) In Comparative Example 5, except that the sintering temperature was 1280° C., in the same manner as in Example 1, a Sn-Zn-O-based oxide sintered body of Comparative Example 5 was obtained. For the Sn-Zn-O-based oxide sintered body of Comparative Example 5, the results of X-ray diffraction analysis performed in the same manner as in Example 1 showed that the wurtzite-type ZnO phase is 34%, and the spinel-type crystal structure is The Zn ₂ SnO ₄ phase is 66% diffraction. No diffraction peaks of other compound phases were measured. In addition, as a result of measuring the relative density and the specific resistance value, the relative density was 91.0%, and the specific resistance value was 14000Ω･cm. That is, it was confirmed that a relative density of 94% or more and a specific resistance of 5Ω･cm or more and 12000Ω･cm or less could not be achieved. The results are shown in Table 2.

(Comparative Example 6) In Comparative Example 6, except that the sintering temperature was set to 1430°C, in the same manner as in Example 1, a Sn-Zn-O-based oxide sintered body of Comparative Example 6 was obtained. With regard to the Sn-Zn-O-based oxide sintered body of Comparative Example 6, X-ray diffraction analysis was 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% diffraction. No diffraction peaks of other compound phases were measured. In addition, as a result of measuring the relative density and the specific resistance value, the relative density was 93.0%, and the specific resistance value was 12500Ω･cm. That is, it was confirmed that a relative density of 94% or more and a specific resistance of 5Ω･cm or more and 12000Ω･cm or less could not be achieved. The results are shown in Table 2.

(Comparative Example 7) In Comparative Example 7, the retention time of sintering at 1350°C was set to 10 hours, except that the Sn-Zn-O system of Comparative Example 7 was obtained in the same manner as in Example 1. Oxide sintered body. For the Sn-Zn-O-based oxide sintered body of Comparative Example 7, X-ray diffraction analysis was 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% diffraction. No diffraction peaks of other compound phases were measured. Also, as a result of measuring the relative density and the specific resistance value, the relative density was 90.0%, and the specific resistance value was 13500Ω･cm. That is, it was confirmed that a relative density of 94% or more and a specific resistance of 5Ω･cm or more and 12000Ω･cm or less could not be achieved. 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 retention time of sintering at 1350°C was 30 hours. Oxide sintered body. For the Sn-Zn-O-based oxide sintered body of Comparative Example 8, X-ray diffraction analysis was 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% diffraction. No diffraction peaks of other compound phases were measured. In addition, as a result of measuring the relative density and specific resistance, ZnO or Zn ₂ SnO ₄ was volatilized, and the relative density was 93.0%, and the specific resistance was 13000Ω･cm. That is, it was confirmed that a relative density of 94% or more and a specific resistance of 5Ω･cm or more and 12000Ω･cm or less could not be achieved. The results are shown in Table 2.

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

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

(Comparative Example 11) In Comparative Example 11, except that the ratio of Ta/(Sn+Zn+Ge+Ta+Ga) was 0.03, it was prepared in the same manner as in Example 1, and Comparative Example 11 was obtained. The Sn-Zn-O series oxide sintered body. For the Sn-Zn-O-based oxide sintered body of Comparative Example 11, X-ray diffraction analysis was 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% diffraction. No diffraction peaks of other compound phases were measured. Furthermore, as a result of measuring the relative density and the specific resistance value, the relative density was 97.0%, and the specific resistance value was 16000Ω･cm. That is, it was confirmed that the specific resistance could not be achieved at 5Ω･cm or more and 12000Ω･cm or less. The results are shown in Table 2.

(Comparative Example 12) In Comparative Example 12, the ratio of Ta/(Sn+Zn+Ge+Ta+Ga) was 0.0001, except that it was prepared in the same manner as in Example 1, and Comparative Example 12 was obtained. The Sn-Zn-O series oxide sintered body. For the Sn-Zn-O based oxide sintered body of Comparative Example 12, X-ray diffraction analysis was 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% diffraction. No diffraction peaks of other compound phases were measured. In addition, as a result of measuring the relative density and the specific resistance value, the relative density was 96.7%, and the specific resistance value was 25000Ω･cm. That is, it was confirmed that the specific resistance could not be achieved at 5Ω･cm or more and 12000Ω･cm or less. The results are shown in Table 2.

(Comparative Example 13) In Comparative Example 13, the ratio of Ga/(Sn+Zn+Ge+Ta+Ga) was 0.2. Except that, in the same manner as in Example 1, Comparative Example 13 was obtained. The Sn-Zn-O series oxide sintered body. For the Sn-Zn-O-based oxide sintered body of Comparative Example 13, X-ray diffraction analysis was 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% diffraction. No diffraction peaks of other compound phases were measured. Also, as a result of measuring the relative density and the specific resistance value, the relative density was 97.3%, and the specific resistance value was 14800Ω･cm. That is, it was confirmed that the specific resistance could not be achieved at 5Ω･cm or more and 12000Ω･cm or less. The results are shown in Table 2.

(Comparative Example 14) In Comparative Example 14, Ga/(Sn+Zn+Ge+Ta+Ga) was prepared at a ratio of 0.0008. In the same manner as in Example 1, except that Ga/(Sn+Zn+Ge+Ta+Ga) was blended, Comparative Example 14 was obtained. The Sn-Zn-O series oxide sintered body. For the Sn-Zn-O-based oxide sintered body of Comparative Example 14, X-ray diffraction analysis was 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% diffraction. No diffraction peaks of other compound phases were measured. Furthermore, as a result of measuring the relative density and the specific resistance value, the relative density was 97.0%, and the specific resistance value was 22000Ω･cm. That is, it was confirmed that the specific resistance could not be achieved at 5Ω･cm or more and 12000Ω･cm or less. 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. However, various modifications that do not actually deviate from the novel matters and effects of the present invention can be easily understood by the industry. Therefore, all such modifications are included in the scope of the present invention.

For example, in the specification or the drawings, the terms that are recorded at least once with the broader or synonymous different terms can be replaced with the different terms anywhere in the specification or the drawings. In addition, the structure of the Sn-Zn-O-based oxide sintered body and its manufacturing method are not limited to those described in one embodiment of the present invention and each example, and various modifications can be implemented.

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

Claims (5)

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, characterized in that it further contains at least germanium (Ge), Tantalum (Ta) and gallium (Ga) are the components, and the metal atom number ratio is Sn/(Zn+Sn) 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 above 0.0005 and below 0.01, Ga/(Zn+Sn+Ge+Ta+Ga) is above 0.001 and below 0.1, and the specific resistance is 5Ω. 12000Ω above cm. cm or less, the relative density is 94% or more. For example, the Sn-Zn-O based oxide sintered body of claim 1, wherein the ratio of metal atoms Sn/(Zn+Sn) is 0.16 or more and 0.23 or less, and the specific resistance is 5Ω. 110Ω above cm. cm or less, the aforementioned relative density is 98% or more. Such as the Sn-Zn-O oxide sintered body of claim 1, wherein the ZnO phase of the wurtzite crystal structure is in the range of 5 to 70% of the total, or the Zn ₂ SnO _{4 of the spinel crystal structure} The phase is composed of the range of 30~95% of the whole. Such as the Sn-Zn-O based oxide sintered body of claim 2, wherein the ZnO phase of the wurtzite crystal structure is in the range of 5 to 70% of the total, or the Zn ₂ SnO _{4 of the spinel crystal structure} The phase is composed of the range of 30~95% 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 with zinc (Zn) and tin (Sn) as components, characterized by having the following steps : A granulation step of mixing zinc oxide powder, tin oxide powder, and oxide powder containing additional elements to produce granulated powder; pressing the aforementioned granulated powder to obtain a molded body A forming step; and a firing step of firing the aforementioned formed body to obtain an oxide sintered body, wherein in the aforementioned firing step, in the atmosphere of the firing furnace environment, the heating rate is 0.3~1.0 The temperature is raised to 1300°C or more and 1400°C or less, 15 hours or more and 25 hours or less to sinter the formed body. The additive elements are at least germanium (Ge), tantalum (Ta), and gallium (Ga) , So that the ratio of metal atom number is Sn/(Zn+Sn) 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 The method is to mix the zinc oxide powder, the tin oxide powder, and the additive element-containing oxide powder.

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