KR101748017B1

KR101748017B1 - Oxide sintered compact, oxide sputtering target, conductive oxide thin film having high refractive index, and method for producing the oxide sintered compact

Info

Publication number: KR101748017B1
Application number: KR1020147033838A
Authority: KR
Inventors: 아츠시 나라
Original assignee: 제이엑스금속주식회사
Priority date: 2013-10-24
Filing date: 2014-01-08
Publication date: 2017-06-15
Also published as: JP5968462B2; JP5913523B2; KR20150059136A; TWI608111B; TW201516168A; WO2015059938A1; CN104736497A; JPWO2015059938A1; JP2015107910A; CN104736497B; JP2015107909A

Abstract

(In) and titanium (Ti) or chromium (Cr) and zinc (Zn) or tin (Sn) and oxygen (O) and contains 2 to 65 mol% of In in terms of In ₂ O ₃ (Atomic percent) of Ti or Cr in terms of TiO ₂ or Cr ₂ O ₃ , 2 to 65 mol% of Ti or Cr in terms of TiO ₂ or Cr ₂ O ₃ , A / B? 5 and 0 <C / (A + B) <10, wherein the atomic ratio of Sn is C (at%). It is possible to form a thin film which is low in bulk resistance, is capable of DC sputtering, and is transparent and has a high refractive index.

Description

FIELD OF THE INVENTION [0001] The present invention relates to an oxide sintered compact, an oxide sputtering target, a conductive oxide thin film having a high refractive index, and a method for manufacturing the oxide sintered compact.

The present invention relates to an oxide-sintered body, an oxide sputtering target, a conductive oxide thin film having a high refractive index, and a method for producing the oxide-sintered body, and more particularly, to a sintered body sputtering target having a low bulk resistance and capable of DC sputtering and a high- .

When visible light is used in various optical devices such as a display and a touch panel, the material to be used needs to be transparent. Particularly, it is preferable that the material has a high transmittance throughout the visible light region. In addition, in various optical devices, light loss due to a refractive index difference at the interface between the film material and the substrate may occur, and as a method for improving the optical loss, There is a method of introducing a film. Since the refractive index required for the optical adjusting film differs depending on the structure of various devices, a wide range of refractive index is required. Depending on the place where it is used, conductivity may be required.

As materials which are generally transparent and conductive, there are known ITO (indium oxide-tin oxide), IZO (indium oxide-zinc oxide), GZO (gallium oxide-zinc oxide), AZO (aluminum oxide-zinc oxide) (Patent Documents 1 to 3). However, these materials can not be used as a high refractive index material (n> 2.05) or a low refractive index material (n <1.95) for optical adjustment because the refractive index at a wavelength of 550 nm falls within a range of about 1.95 to 2.05. In addition, ITO has a problem that it is difficult to use ITO for plastic substrate or organic EL device which can not be heated because the substrate is heated at the time of film formation or annealing is required after film formation in order to increase the transmittance. Further, since IZO has absorption at a short wavelength side, there is a problem that it becomes a yellowish film.

Japanese Patent Application Laid-Open No. 2007-008780 JP-A-2009-184876 Japanese Patent Application Laid-Open No. 2007-238375

An object of the present invention is to provide a sintered body capable of obtaining a conductive thin film capable of realizing high transmittance and high refractive index of visible light. This thin film is useful as a thin film for optical devices such as a display and a touch panel, and particularly as an optical adjusting thin film because of its high transmittance and high refractive index. Another object of the present invention is to provide a sputtering target which has a high relative density, a low bulk resistance and is capable of DC sputtering. An object of the present invention is to improve characteristics of an optical device, reduce facility cost, and dramatically improve film forming characteristics.

Means for Solving the Problems In order to solve the above problems, the present inventors have conducted intensive studies and, as a result, it has become possible to obtain a conductive thin film having a high transmittance and a high refractive index by employing the material system described below, , It is possible to perform stable film formation by DC sputtering, and it is possible to improve the characteristics of the optical device using the thin film and improve the productivity.

The present invention provides the following invention based on this finding.

1) indium (In), and titanium (Ti) or chromium (Cr), and zinc (Zn) or tin (Sn) and is made of the oxygen (O), the In to In ₂ O ₃ in terms of 2 ~ 65 ㏖% (Atomic%), Ti (atomic%) or Cr (atomic ratio) is B (at%), and Ti or Cr is in the range of 2 to 65 mol% in terms of TiO ₂ or Cr ₂ O ₃ , A / B? 5 and 0 <C / (A + B) <10, wherein the atomic ratio of Zn or Sn is C (at%

2) In contains 2 to 30 mol% in terms of In ₂ O ₃ , Ti or Cr in terms of TiO ₂ or 3 to 30 mol% in terms of Cr ₂ O ₃ , Zn or Sn in terms of ZnO or SnO _By mass of the sintered body according to the above 1)

3) The sintered body according to 1) or 2) above, wherein 0 <C / (A + B) <5,

4) The sintered body according to any one of 1) to 3) above, wherein the relative density is 90% or more,

5) The sintered body according to any one of 1) to 4) above, wherein the bulk resistance is 10 Ω · cm or less,

6), indium (In), and titanium (Ti) or chromium (Cr), and zinc (Zn) or tin (Sn) and is made of the oxygen (O), the In to In ₂ O ₃ in terms of 2 ~ 65 ㏖% (Atomic%), Ti (atomic%) or Cr (atomic ratio) is B (at%), and Ti or Cr is in the range of 2 to 65 mol% in terms of TiO ₂ or Cr ₂ O ₃ , A / B? 5 and 0 <C / (A + B) <10, wherein the atomic ratio of Zn or Sn is C (at%

7) The thin film according to 6) above, wherein the refractive index at a wavelength of 550 nm is 2.05 or more,

(8) The thin film according to (6) or (7) above, wherein an extinction coefficient at a wavelength of 450 nm is 0.05 or less,

9) The thin film according to any one of the above 6) to 8), wherein the resistivity is 1 M? 占㎝ m or less,

(10) A method for producing a sintered body according to any one of (1) to (5), wherein the raw material powder is pressed and sintered at 900 ° C. or higher and 1500 ° C. or lower in an inert gas or vacuum atmosphere, or the raw material powder is press- Is sintered under normal pressure at a temperature of 1000 ° C or more and 1500 ° C or less under an inert gas or a vacuum atmosphere.

According to the present invention, it is possible to obtain a conductive film having a high transmittance and a high refractive index by employing the material system described above, thereby securing desired optical characteristics. Further, the present invention has an excellent effect of remarkably improving the productivity by improving various optical device characteristics, reducing the equipment cost, and improving the film forming speed.

The present invention is indium (In), and titanium (Ti) or chromium (Cr), and zinc (Zn) or tin (Sn) and is made of the oxygen (O), 2 ~ 65 ㏖ the In to In ₂ O ₃ in terms of (Atomic%) of Ti or Cr in terms of TiO ₂ or 2 to 65 mol% in terms of Cr ₂ O ₃ , the atomic ratio of In is A (at%), the atomic ratio of Ti or Cr is B , A / B? 5 and 0 <C / (A + B) <10, wherein the atomic ratio of Zn or Sn is C (at%). Thereby, a conductive film having a high transmittance and a high refractive index can be obtained.

The material of the present invention contains indium (In) and titanium (Ti) or chromium (Cr), zinc (Zn), tin (Sn) and oxygen (O) as constituent elements, Impurities are also included.

The material system of the present invention is a material system having a composition represented by the following formula: M ¹ M ² O ₃ (M ³ O) _m (M ¹ : first component, M ² : second component, M ³ : third component, In or Fe as a first component and Ti, Cr, In, Fe or Sn as a second component, and a rare earth element such as As the three components, Zn, Sn, Cu, Mn, Fe or Co may be mentioned. However, Fe, Cu, Mn, and Co are not preferable because they have small band gaps and cause absorption in the visible light region.

Therefore, it is determined that In is adopted as the first component. It is determined that Zn or Sn is adopted for the third component. Further, since In or Sn can not be used as the second component in order to increase the refractive index, it is determined that Ti or Cr is adopted as the second component.

In the present invention, the content of In is 2 to 65 mol% in terms of In ₂ O ₃ . And more preferably 2 to 30 mol%. The content of Ti or Cr is 3 to 65 mol% in terms of TiO ₂ or Cr ₂ O ₃ , respectively. And more preferably 3 to 30 mol%. The content of Zn or Sn as the third component can be derived from the content of In and the content of Ti or Cr and the C / (A + B) atomic ratio defined above, but is preferably 40 mol% or more in terms of ZnO or SnO . Thereby, it is possible to realize a conductive film having a desired high transmittance and a high refractive index.

In the present invention, the A / B atomic ratio is 0.5 A / B 5. Exceeding this range is not preferable because desired optical characteristics can not be obtained. Particularly, when A / B is 5 or more, there is a problem that the content of the high refractive index material (Ti or Cr) is reduced and the refractive index is lowered. In the present invention, the atomic ratio C / (A + B) is 0 <C / (A + B) <10, and more preferably 0 <C / (A + B) <5. Exceeding this range leads to a problem that the content of the high refractive index material is reduced in the same manner as described above, and a desired high refractive index can not be obtained.

When used as a sputtering target, the sintered body of the present invention preferably has a relative density of 90% or more. The improvement in density has the effect of enhancing the uniformity of the sputter film and suppressing the generation of particles at the time of sputtering. The relative density of 90% or more can be realized by a manufacturing method of a sintered body of the present invention to be described later.

When the sintered body of the present invention is used as a sputtering target, the bulk resistance is preferably 10 Ω · cm or less. It is possible to form the film by the DC sputtering due to the lowering of the bulk resistance. The DC sputtering has a higher film forming speed than the RF sputtering, has excellent sputtering efficiency, and can improve the throughput. Further, RF sputtering may be carried out depending on the manufacturing conditions, but in this case also, the film forming speed is improved.

The thin film produced by the sputtering of the present invention can achieve a refractive index of 2.05 or more at a wavelength of 550 nm. Further, the thin film of the present invention can attain an extinction coefficient of 0.05 or less at a wavelength of 450 nm. In addition, the thin film of the present invention can achieve a specific resistance of 1 M? 占 이하 m or less. Such a conductive thin film having a high refractive index and a high transmittance is useful as an optical adjusting thin film for an optical device such as a display or a touch panel. Particularly, the present invention can provide a high-refractive-index film having an extinction coefficient of 0.01 or less at a wavelength of 450 nm and having no absorption at a short wavelength, and thus can be regarded as an excellent material system for obtaining desired optical characteristics.

In the thin film of the present invention, there are those which become the crystallization film and the amorphous film in the above-mentioned composition range. In addition, some of them are partially crystallized to coexist with each other. In the present invention, the crystallinity of such a film is not particularly limited, but it is possible to adjust the composition in accordance with desired crystallinity. The crystallinity of the film (crystallized film, amorphous film, or partially crystallized film) can be evaluated by the presence or absence of a diffraction peak by the X-ray diffraction method.

The sintered body of the present invention can be obtained by press-sintering (hot pressing) the raw powder composed of the oxide powder of each constituting metal under an inert gas atmosphere or a vacuum atmosphere, or by press molding the raw powder, can do. At this time, the sintering temperature is preferably 900 ° C or more and 1500 ° C or less. If the temperature is lower than 900 占 폚, a high-density sintered body can not be obtained. On the other hand, if it exceeds 1500 占 폚, compositional deviation and density decrease due to evaporation of the material occur.

Example

The following is a description based on examples and comparative examples. Note that this embodiment is merely an example, and is not limited at all by this example. That is, the present invention is limited only by the claims, and includes various modifications other than the embodiments included in the present invention.

The evaluation methods in Examples and Comparative Examples are as follows.

(About composition of ingredients)

Apparatus: SPS3500DD manufactured by SII

Method: ICP-OES (high frequency inductively coupled plasma emission spectrometry)

(Relative to relative density)

The density of the sintered body was calculated from the volume and the measured weight by measuring the dimensions of the sintered body with a vernier caliper.

The theoretical density is obtained by summing up values obtained by multiplying each of the single densities of the oxides of the starting materials by the mixing mass ratio, as shown below. The relative density was obtained by dividing the density of the oxide-sintered body by the theoretical density and multiplying by 100.

Theoretical density = SIGMA {(mass density of each oxide x mixed mass ratio) + (mass density of each oxide x mixed weight ratio) + }

Relative density = {(density of sintered body) / (theoretical density)} x 100

(For bulk resistance [resistivity, sheet resistance]),

Apparatus: Resistivity measuring instrument manufactured by NPS Σ-5 +

Method: DC 4 probe method

(For refractive index, extinction coefficient)

Apparatus: Spectrophotometer UV-2450 manufactured by SHIMADZU

Method: Calculated from transmittance and surface reflectance

(About film forming method, condition)

Device: ANELVA SPL-500

Substrate: Φ4 inch

Substrate temperature: room temperature

(Example 1)

In ₂ O ₃ powder, TiO ₂ powder and ZnO powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. Next, the mixed powder was hot-pressed and sintered under the conditions of an argon atmosphere at a temperature of 1150 DEG C and a pressure of 250 kgf / cm < 2 >. Thereafter, the sintered body was machined and finished in a target shape.

Next, sputtering was carried out using the finishing-processed target having a diameter of 6 inches. The sputtering conditions were a DC sputtering, a sputtering power of 500 W, an Ar gas pressure of 0 to 2 vol% containing oxygen at 0.5 Pa, and a film thickness of 5000 angstroms. Further, the substrate was not heated during sputtering or annealed after sputtering.

The results are shown in Table 1. As shown in Table 1, the sputtering target had a relative density of 98.9% and a bulk resistance of 2.9 x 10 < ~ ³ > The thin film formed by sputtering has a refractive index of 2.10 (wavelength: 550 nm), an extinction coefficient of 0.01 (wavelength: 450 nm), a resistance value of 2.3 x 10 ^-2 Ω · cm or more, a high refractive index, I was able to get a film. The resistance value is slightly fluctuated by the amount of oxygen at the time of sputtering, and when the amount of oxygen is increased, the resistance value tends to increase. Therefore, the lower limit value is described.

(Example 2)

In ₂ O ₃ powder, TiO ₂ powder and ZnO powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. Next, the mixed powder was hot-pressed and sintered under the conditions of an argon atmosphere at a temperature of 1150 DEG C and a pressure of 250 kgf / cm < 2 >. Thereafter, the sintered body was machined and finished in a target shape. Next, sputtering was carried out under the same conditions as in Example 1 using the finishing target having a diameter of 6 inches. As a result, the sputtering target had a relative density of 100.3% and a bulk resistance of 8.7 x 10 < ^-3 > OMEGA .cm, which enabled stable DC sputtering. The thin film formed by sputtering has a refractive index of 2.15 (wavelength: 550 nm), an extinction coefficient of less than 0.01 (wavelength: 450 nm) and a resistance value of 1.8 x 10 ⁺ .

(Example 3)

In ₂ O ₃ powder, TiO ₂ powder and ZnO powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. Next, this mixed powder was subjected to hot press sintering under the conditions of an argon atmosphere at a temperature of 1100 DEG C and a pressure of 250 kgf / cm < 2 >. Thereafter, the sintered body was machined and finished in a target shape. Next, sputtering was carried out under the same conditions as in Example 1 using the finishing target having a diameter of 6 inches. As a result, the sputtering target had a relative density of 99.5% and a bulk resistance of 3.5 x 10 < ^-3 > OMEGA .cm, which enabled stable DC sputtering. The thin film formed by sputtering has a refractive index of 2.22 (wavelength: 550 nm), an extinction coefficient of less than 0.01 (wavelength: 450 nm) and a resistance value of 1.2 x 10 ⁺ .

(Example 4)

In ₂ O ₃ powder, Cr ₂ O ₃ powder and ZnO powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. Next, the mixed powder was hot-pressed and sintered under the conditions of an argon atmosphere at a temperature of 1100 占 폚 and a pressure of 350 kgf / cm2. Thereafter, the sintered body was machined and finished in a target shape. Next, sputtering was carried out under the same conditions as in Example 1 using the finishing target having a diameter of 6 inches. As a result, the sputtering target had a relative density of 100.2% and a bulk resistance of 8.0 x 10 < ~ ⁴ > The thin film formed by sputtering has a refractive index of 2.10 (wavelength: 550 nm), an extinction coefficient of 0.02 (wavelength: 450 nm), a resistance value of 2.8 x 10 ^-2 ? 占㎝ m or more, a high refractive index, .

(Example 5)

In ₂ O ₃ powder, TiO ₂ powder and ZnO powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. Next, the mixed powder was hot-pressed and sintered under the conditions of an argon atmosphere at a temperature of 1150 DEG C and a pressure of 250 kgf / cm < 2 >. Thereafter, the sintered body was machined and finished in a target shape. Next, sputtering was carried out under the same conditions as in Example 1 using the finishing target having a diameter of 6 inches. As a result, the sputtering target had a relative density of 100.1% and a bulk resistance of 9.6 x 10 < ~ ⁴ > The thin film formed by sputtering has a refractive index of 2.12 (wavelength: 550 nm), an extinction coefficient of less than 0.01 (wavelength: 450 nm), a resistance value of 8.7 x ^10-3 ? I was able to get a film.

(Example 6)

In ₂ O ₃ powder, TiO ₂ powder and ZnO powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. Next, this mixed powder was subjected to hot press sintering under the conditions of an argon atmosphere at a temperature of 1100 DEG C and a pressure of 250 kgf / cm < 2 >. Thereafter, the sintered body was machined and finished in a target shape. Next, sputtering was carried out under the same conditions as in Example 1 using the finishing target having a diameter of 6 inches. As a result, the sputtering target had a relative density of 99.8% and a bulk resistance of 8.4 x 10 < ~ ⁴ > The thin film formed by sputtering has a refractive index of 2.05 (wavelength: 550 nm), an extinction coefficient of less than 0.01 (wavelength: 450 nm), a resistance value of 9.3 x ^10-3 ? I was able to get a film.

(Example 7)

In ₂ O ₃ powder, Cr ₂ O ₃ powder and ZnO powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. Next, this mixed powder was subjected to hot press sintering under the conditions of an argon atmosphere at a temperature of 1150 DEG C and a pressure of 350 kgf / cm < 2 >. Thereafter, the sintered body was machined and finished in a target shape. Next, sputtering was carried out under the same conditions as in Example 1 using the finishing target having a diameter of 6 inches. As a result, the sputtering target had a relative density of 98.2% and a bulk resistance of 5.2 x 10 < ^-3 > OMEGA. Cm, which enabled stable DC sputtering. The thin film formed by sputtering has a refractive index of 2.07 (wavelength: 550 nm), an extinction coefficient of 0.03 (wavelength: 450 nm) and a resistance value of 3.6 x 10 ^-2 ? 占㎝ m or more, .

(Example 8)

In ₂ O ₃ powder, TiO ₂ powder and SnO ₂ powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. Next, after the mixed powder was press molded, the formed body was sintered at room temperature under a condition of 1300 캜 under an argon atmosphere. Thereafter, the sintered body was machined and finished in a target shape. Next, sputtering was carried out under the same conditions as in Example 1 using the finishing target having a diameter of 6 inches. As a result, the sputtering target had a relative density of 97.8% and a bulk resistance of 8.7 x 10 < ^-2 > The thin film formed by sputtering has a refractive index of 2.08 (wavelength: 550 nm), an extinction coefficient of 0.01 (wavelength: 450 nm) and a resistance value of 3.1 x 10 ¹ ? · Cm or more to obtain a conductive film of high refractive index and high transmittance I could.

(Comparative Example 1)

In ₂ O ₃ powder, Fe ₂ O ₃ powder and ZnO powder were prepared, and these powders were combined and mixed at the compounding ratios shown in Table 1. Next, this mixed powder was hot-pressed and sintered under the conditions of an argon atmosphere at a temperature of 1050 DEG C and a pressure of 350 kgf / cm < 2 >. Thereafter, the sintered body was machined and finished in a target shape. Next, sputtering was carried out under the same conditions as in Example 1 using the finishing target having a diameter of 6 inches. As a result, in the thin film formed by sputtering, light absorption occurred in the low wavelength region with an extinction coefficient of 0.16 (wavelength: 450 nm), and a desired high transmittance film could not be obtained.

(Comparative Example 2)

In ₂ O ₃ powder, TiO ₂ powder and CuO powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. Next, this mixed powder was hot-pressed and sintered under the conditions of an argon atmosphere at a temperature of 1050 DEG C and a pressure of 350 kgf / cm < 2 >. Thereafter, the sintered body was machined and finished in a target shape. Next, sputtering was carried out under the same conditions as in Example 1 using the finishing target having a diameter of 6 inches. As a result, the thin film formed by sputtering had an extinction coefficient of 0.2 or more (with a wavelength of 450 nm), absorption of light occurred in a low wavelength region, and a desired high transmittance film could not be obtained.

(Comparative Example 3)

In ₂ O ₃ powder, TiO ₂ powder and ZnO powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. At this time, the atomic ratio of In / Ti was increased to 8.0. Next, the mixed powder was hot-pressed and sintered under the conditions of an argon atmosphere at a temperature of 1150 DEG C and a pressure of 250 kgf / cm < 2 >. Thereafter, the sintered body was machined and finished in a target shape. Next, sputtering was carried out under the same conditions as in Example 1 using the finishing target having a diameter of 6 inches. As a result, the thin film formed by sputtering had a refractive index of 2.01 (wavelength: 550 nm), the refractive index was lowered, and a desired high refractive index film could not be obtained.

(Comparative Example 4)

In ₂ O ₃ powder, TiO ₂ powder and ZnO powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. At this time, the atomic ratio of Zn / (In + Ti) was increased to 15. Next, this mixed powder was hot-pressed and sintered under the conditions of an argon atmosphere at a temperature of 1050 DEG C and a pressure of 250 kgf / cm < 2 >. Thereafter, the sintered body was machined and finished in a target shape. Next, sputtering was carried out under the same conditions as in Example 1 using the finishing target having a diameter of 6 inches. As a result, the thin film formed by sputtering had a refractive index of 2.02 (wavelength: 550 nm), the refractive index was lowered, and a desired high refractive index film could not be obtained.

Industrial availability

The thin film formed by the sputtering of the present invention forms a part of a thin film for optical adjustment or an optical disk structure in a display or a touch panel, and has an effect of having very excellent characteristics in terms of transmittance, refractive index and conductivity.

In addition, the sputtering target made of the sintered body of the present invention has a low bulk resistance value and high density, which makes stable DC sputtering possible. The controllability of the sputter, which is a feature of this DC sputtering, is facilitated, and the sputtering efficiency can be improved by increasing the deposition rate. In addition, the quality of the film can be improved by reducing the particles generated during sputtering at the time of film formation.

Claims

(2), wherein the oxide film contains 2 to 20 mol% of In in terms of In ₂ O ₃ , 2 to 15.4 mol% of Ti in terms of TiO ₂ , (Atomic%) of Ti, B (at%) and C (at%) of the atomic ratio of Zn, wherein the atomic ratio of In is at least 60% , 0.5? A / B? 5, 0 <C / (A + B) <10, and a bulk resistance of 8.7 m? · Cm or less.

(2), wherein the alloy contains 2 to 20 mol% of In in terms of In ₂ O ₃ , 2 to 15.4 mol% of Ti in terms of TiO ₂ , 2 to 20 mol% of In, Ti, (Atomic%) of Ti, atomic ratio of B (at%), and atomic ratio of Sn to C (at%), wherein the atomic ratio of In is at least 80% by mole in terms of SnO ₂ 0.5? A / B? 5, 0 <C / (A + B) <10, and a bulk resistance of 8.7 m? · Cm or less.

3. The method according to claim 1 or 2,
Ti in an amount of 3 to 15.4 mol% in terms of TiO ₂ .

3. The method according to claim 1 or 2,
0 < C / (A + B) < 5.

3. The method according to claim 1 or 2,
And a relative density of 90% or more.

(2), wherein the oxide film contains 2 to 20 mol% of In in terms of In ₂ O ₃ , 2 to 15.4 mol% of Ti in terms of TiO ₂ , (Atomic%) of Ti, B (at%) and C (at%) of the atomic ratio of Zn, wherein the atomic ratio of In is at least 60% , 0.5? A / B? 5 and 0 <C / (A + B) <10, a refractive index at a wavelength of 550 nm of 2.05 or more, and an extinction coefficient at a wavelength of 450 nm of 0.05 or less Thin film for optical adjustment.

(2), wherein the alloy contains 2 to 20 mol% of In in terms of In ₂ O ₃ , 2 to 15.4 mol% of Ti in terms of TiO ₂ , 2 to 20 mol% of In, Ti, (Atomic%) of Ti, atomic ratio of B (at%), and atomic ratio of Sn to C (at%), wherein the atomic ratio of In is at least 80% by mole in terms of SnO ₂ , Wherein 0.5? A / B? 5 and 0 <C / (A + B) <10, a refractive index at a wavelength of 550 nm is 2.05 or more, and an extinction coefficient at a wavelength of 450 nm is 0.05 or less A thin film for optical adjustment.

A method for producing a sintered body according to any one of claims 1 to 3, wherein the raw material powder is sintered under pressure in an inert gas or a vacuum atmosphere at a temperature of 900 ° C to 1500 ° C or press- And sintering at atmospheric pressure at a temperature of 1000 ° C or more and 1500 ° C or less in a vacuum atmosphere.

Indium (In), chromium (Cr), zinc (Zn) or tin (Sn), and is made of the oxygen (O), In the In ₂ O ₃ in terms of 2 ~ 65 ㏖%-containing and, Cr ₂ O to Cr to ₃ in terms of containing 2 ~ 65 ㏖% (however, in an atomic ratio to the total metal content of components excluding unavoidable impurities, Cr: except when 8.0 at% 11.0 at%, Zn :: 81.0 at%, in) A / B &le; 5 and 0 &le; 2, where A (at%), C / (A + B) < 10.

10. The method of claim 9,
And Cr in an amount of 2 to 30 mol% in terms of In ₂ O ₃ and 3 to 30 mol% of Cr in terms of Cr ₂ O ₃ (provided that the atomic ratio to the total amount of the metal components other than inevitable impurities is Cr: 11.0 at%, Zn: 81.0 at%, and In: at 8.0 at%), Zn or Sn in an amount of at least 40 mol% in terms of ZnO or in terms of SnO ₂ , respectively.

11. The method according to claim 9 or 10,
0 < C / (A + B) < 5.

11. The method according to claim 9 or 10,
And a relative density of 90% or more.

11. The method according to claim 9 or 10,
And a bulk resistance of 10 Ω · cm or less.

15. The method of claim 14,
Wherein the refractive index at a wavelength of 550 nm is 2.05 or more.

16. The method according to claim 14 or 15,
Wherein an extinction coefficient at a wavelength of 450 nm is 0.05 or less.

16. The method according to claim 14 or 15,
And a specific resistance of 1 M? 占㎝ m or less.

The method for producing a sintered body according to any one of claims 9 to 10, wherein the raw material powder is pressed and sintered at 900 ° C or more and 1500 ° C or less under an inert gas or a vacuum atmosphere, or the raw material powder is press- And sintering at atmospheric pressure at a temperature of 1000 ° C or more and 1500 ° C or less in a vacuum atmosphere.