KR20160041013A - Oxide sintered compact and method of producing same, oxide sputtering target, and conductive oxide film - Google Patents

Abstract

Provided is an oxide sintered body composed of indium (In), titanium (Ti), zinc (Zn), tin (Sn) and oxygen (O). More particularly, the oxide sintered body of the present invention has: an atomic number ratio of In to Ti satisfying an equation of 3.0 <= In/Ti <= 5.0; the atomic number ratio of Zn and Sn to In and Ti satisfying an equation of 0.2 <= (Zn+Sn)/(In+Ti) <= 1.5; and the atomic number ratio of Zn to Sn satisfying an equation of 0.5 <= Zn/Sn <= 7.0. The oxide sintered body of the present invention has low volume resistivity and is capable of DC sputtering. A transparent conductive film with high refractive index can be formed using the oxide sintered body of the present invention.

Description

FIELD OF THE INVENTION [0001] The present invention relates to an oxide sintered body, a method of manufacturing the same, an oxide sputtering target, and a conductive oxide thin film.

The present invention relates to an oxide-sintered body, an oxide-sputtering target, a conductive oxide thin film and a method of manufacturing the oxide-sintered body, and more particularly to an oxide-sintered material sputtering target suitable for forming a conductive oxide thin film of amorphous with a high transmittance and a high refractive index .

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, and in particular, it is desired to have a high transmittance throughout the visible light region. In addition, in various optical devices, there is a case where light loss due to the difference in refractive index between the film material and the substrate is generated, and as a method for improving the light loss, optical adjustment for adjusting the refractive index and optical film thickness 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. Also, depending on the place where it is used, conductivity may be required.

In recent years, in addition to the refractive index and the extinction coefficient (high transmittance), in addition to the refractive index and the extinction coefficient (high transmittance), the conductivity and the etching property Etching capability), water resistance, and amorphous film. In order to coexist such a plurality of characteristics, it is difficult to form a single oxide film, and a composite oxide film in which a plurality of oxides are mixed is required. Particularly, a composite oxide film in which oxides of three or more systems are mixed is effective.

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) . However, these materials converge in the range of about 1.95 to 2.05 at a wavelength of 550 nm, and can not be used as a high refractive index material (n> 2.05) for optical adjustment. In addition, since ITO has to be heated at the time of film formation or annealed after film formation in order to increase the transmittance, there is a problem that it is difficult to use ITO for plastic substrate or organic EL device which can not be heated. Further, since IZO has absorption at a short wavelength side, it has a problem that it becomes a yellowish film.

The present inventor has succeeded in forming a conductive amorphous thin film having a high transmittance and a high refractive index using the oxide-sintered product sputtering target whose composition has been previously adjusted (Patent Document 1). However, as a result of conducting the research, it has been found that such a crystallized film may not be suitable when used as a flexible device or when protection against moisture is required. Further, depending on the use of the thin film, a crystallized film may be preferable. In the case of the thin film transistor, a stable film can not be obtained as an amorphous film in Patent Document 2. In the past, although a wide range of composition as a transparent conductive film has been known (for example, Patent Document 3), there has been no case where the crystallinity of the film is particularly conscious.

Japanese Patent Application No. 2013-220805 International Publication WO2012 / 153507 Japanese Patent Publication No. 4994068 International Publication WO2010 / 058533

An object of the present invention is to provide a sintered body capable of realizing a high transmittance and a high refractive index of visible light and capable of obtaining a conductive thin film. This thin film is useful as a thin film for an optical device such as a display or a touch panel, particularly a thin film for optical adjustment, because it has a high transmittance and a high refractive index. Another object of the present invention is to provide a sputtering target that has a high relative density and a low volume resistivity and is capable of DC sputtering. An object of the present invention is to improve characteristics of an optical device, reduce facility cost, and significantly improve the characteristics of film formation.

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 using 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 inventors provide the following invention based on this finding.

(In), titanium (Ti), zinc (Zn), tin (Sn) and oxygen (O) The content of Zn and Sn in terms of atomic ratio to Ti satisfies the relation of 0.2? (Zn + Sn) / (In + Ti)? 1.5 and the content of Zn to Sn is 0.5? Zn / Sn? And an oxide sintered body.

2) The oxide-sintered body according to 1) above, wherein the relative density is 90% or more.

3) The oxide-sintered body according to 1) or 2), wherein the volume resistivity is 10 Ω cm or less.

(4) A thin film made of indium (In), titanium (Ti), zinc (Zn), tin (Sn) and oxygen (O), wherein the content of In with respect to Ti is 3.0 ≦ In / Ti ≦ 5.0, The content of Zn and Sn in terms of atomic ratio to Ti satisfies the relation of 0.2? (Zn + Sn) / (In + Ti)? 1.5 and the content of Zn to Sn is 0.5? Zn / Sn? &Lt; / RTI &gt;

5) The film according to 4) above, wherein the refractive index at a wavelength of 550 nm is 2.05 or more.

6) The film according to 4) or 5), wherein an extinction coefficient at a wavelength of 405 nm is 0.05 or less.

7) The membrane according to any one of 4) to 6) above, wherein the volume resistivity is 1 ㏁ or less.

(8) The membrane according to any one of (4) to (7) above, wherein the membrane is amorphous.

(9) A method for producing an oxide-sintered body according to any one of (1) to (3), wherein the raw material powder is pressed and sintered at 900 ° C. or higher and 1300 ° C. or lower in an inert gas or vacuum atmosphere, And sintering the molded body under atmospheric pressure in an inert gas or a vacuum atmosphere at a temperature of 1000 ° C or higher and 1500 ° C or lower.

According to the present invention, it is possible to obtain a conductive film (particularly, an amorphous film) having a high transmittance and a high refractive index by employing the material system described above, thereby securing a desired optical characteristic, And high temperature and high humidity resistance can be ensured. Further, the present invention has an excellent effect of remarkably improving the productivity by improving the characteristics of various optical devices, reducing the equipment cost, and improving the film forming speed.

1 is an X-ray diffraction spectrum of a film formed by sputtering of the present invention.

The oxide sintered body of the present invention is made of indium (In), titanium (Ti), zinc (Zn), tin (Sn) and oxygen (O), and the content of In with respect to Ti is 3.0? (Zn + Sn) / (In + Ti) &lt; / = 1.5, and the content of Zn to Sn is 0.5? Zn / Sn? Of the first and second regions.

By using a sputtering target made of this oxide-sintered body, a conductive oxide film of amorphous can be obtained with a high transmittance and a high refractive index. The material of the present invention contains indium (In), titanium (Ti), zinc (Zn), tin (Sn), and oxygen (O) as constituent elements. Inevitable impurities are also contained in the material.

The film of In-Ti-Zn-O (indium oxide-titanium oxide-zinc oxide) tends to be crystallized in a composition region having good conductivity and also has a high transmittance and low resistance at the time of sputtering And there is a problem that it is difficult to adjust the characteristics. When the content of ZnO is large, the conductivity due to the oxygen deficiency of ZnO is predominant. This oxygen deficiency causes the occurrence of light absorption (low transmittance) while developing conductivity (lowering resistance). However, it is desired to form (crystallize) a homologous structure of IZTO by adding a predetermined ratio of tin (Sn) to this system, but it can be amorphous without being crystallized under the quench film such as sputtering. Further, the addition of such tin makes it possible to achieve both a high transmittance and a low resistance, so that it is easy to adjust the characteristics. It is considered that this is because the above-described conductive mechanism is changed by the addition of tin.

In addition, the addition of a predetermined proportion of tin has a secondary effect that gives good etching property and high temperature and high humidity resistance.

In the present invention, the content of In with respect to Ti is determined so as to satisfy the relation of 3.0? In / Ti? 5.0 by atomic number ratio. When the atomic ratio In / Ti is less than 3.0, high resistance is obtained. On the other hand, when the atomic ratio In / Ti exceeds 5.0, the light absorption becomes large , There is a problem that a high refractive index can not be obtained. However, even if it exceeds the above range, comparatively good optical and electrical characteristics can be obtained when the content of In relative to Ti is 2.5? In / Ti? 7.0 in atomic number ratio.

In the present invention, the total content of Zn and Sn relative to the total content of In and Ti satisfies the relationship of 0.1? (Zn + Sn) / (In + Ti)? Exceeding this range is not preferable because desired optical and electrical characteristics can not be obtained. In particular, when the atomic ratio (Zn + Sn) / (In + Ti) is less than 0.1, there is a problem of high resistance. On the other hand, There is a problem in that the light absorption is increased. If the total content of Zn and Sn relative to the total content of In and Ti is 0.1? (Zn + Sn) / (In + Ti)? 3.5 in terms of atomic ratio, even if it exceeds the above range, , And electrical characteristics are obtained.

Further, in the present invention, the content of Zn to Sn is satisfied with the relation of 0.5? Zn / Sn? 7.0 by atomic number ratio. Exceeding this range is not preferable because desired optical and electrical characteristics can not be obtained. In particular, when the atomic ratio Zn / Sn is less than 0.5, high resistance is obtained. On the other hand, when the atomic ratio Zn / Sn exceeds 7.0, the film is crystallized and the light absorption becomes large. However, even if it exceeds the above range, relatively good optical and electrical characteristics can be obtained when the content of Zn with respect to Sn is 0.1? Zn / Sn? 10.0 in atomic number ratio.

Sintered body of the present invention, indium (In), titanium (Ti), zinc (Zn), and tin (Sn), but characterized in that satisfies the defensive the atom, the content of each component is, the In content of In ₂ It is preferable that the Ti content is 4 to 40 mol% in terms of TiO ₂ , the Zn content is 4 to 60 mol% in terms of ZnO, and the Sn content is 5 to 40 mol% in terms of SnO in terms of O ₃ Do. The sintered body target having such a composition range is effective for obtaining a conductive thin film having excellent optical characteristics and electrical characteristics. In the above description, the content of each metal in the sintered body is expressed in terms of oxide, which is suitable for adjusting the blending of the raw materials with oxides. Further, in a conventional analyzer, the content (wt.%) Of each metal element, not the oxide, can be specified. Therefore, in order to specify each composition of the target, the content of each metal element may be specified by the amount (mol%) converted on the assumption of each oxide.

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 volume resistivity is preferably 10 cm or less. Due to the lowering of the volume resistivity, film formation by DC sputtering becomes possible. DC sputtering has a higher film forming speed and sputtering efficiency than RF sputtering, and can improve throughput. Depending on the manufacturing conditions, RF sputtering may be carried out. In this case, however, the film forming speed is improved.

The thin film produced by the sputtering of the present invention is characterized by being amorphous. The amorphous film is particularly suitable as a material for a flexible device and a material having a low water permeability (moisture protection). Further, the thin film 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 405 nm. Further, the thin film of the present invention can achieve a volume resistivity of 1 M OMEGA or less. Such a conductive thin film having a high refractive index and a high transmittance is a thin film for optical adjustment and is useful for an optical device such as a display or a touch panel. Particularly, in the present invention, a film having a high refractive index with almost no absorption in a short wavelength range of visible light can be obtained with an extinction coefficient of 0.05 or less at a wavelength of 405 nm, and therefore, it is an excellent material system for obtaining desired optical characteristics .

The sintered body of the present invention is obtained by pressing and sintering raw material powder composed of oxide powder of each constituting metal in an inert gas atmosphere or a vacuum atmosphere at a temperature of 900 DEG C or more and 1300 DEG C or less or press molding the raw material powder, It is preferable to perform the normal pressure sintering in a gas or vacuum atmosphere at a temperature of 1000 ° C or higher and 1500 ° C or lower. Density sintered body can not be obtained when the pressure sintering is performed at a temperature of less than 900 ° C and atmospheric pressure sintering is less than 1000 ° C. On the other hand, when the pressure sintering exceeds 1,300 ° C and the normal pressure sintering exceeds 1,500 ° C, The density is lowered, which is undesirable. In addition, if pressure sintering is performed at a temperature higher than 1300 DEG C, there is a possibility of reacting with a mold made of carbon. The press pressure is preferably 150 to 500 kgf / cm 2. In Patent Document 4, two-stage sintering is performed in order to precipitate an In ₂ O ₃ phase containing both Zn and Sn, thereby lowering the volume resistivity. In the present invention, however, So that such two-step sintering is not carried out.

Further, in order to improve the density, it is effective to weigh and mix the raw material powder, then calcine (synthesize) the mixed powder, and then finely pulverize the powder to use as the sintering powder. By performing synthesis and finely pulverizing in advance in this way, a uniform fine raw material powder can be obtained and a dense sintered body can be produced. The average particle diameter after fine pulverization is 5 mu m or less, preferably, the average particle diameter is 2 mu m or less. The firing temperature is preferably 800 ° C or higher and 1200 ° C or lower. By setting this range, the sinterability is improved, and further high density can be achieved.

The evaluation methods in the present invention (including 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)

(For density measurement)

Dimensional measurement (Nogis), weighing

(Relative to relative density)

Next, the theoretical density is calculated.

Relative density (%) = dimensional density / theoretical density x 100

The theoretical density is calculated from the compounding ratio of oxide of each metal element.

A (wt%) in terms of In ₂ O ₃ in In, b (wt%) in terms of TiO ₂ conversion of Ti,

C (wt%) in terms of ZnO converted to Zn, d (wt%) in terms of SnO ₂ converted to Sn,

, &Lt; / RTI &

Theoretical density = 100 / (a / 7.18 + b / 4.26 + c / 5.61 + d / 7.0)

The oxide-equivalent density of each metal element is given by the following value.

_{In 2 O 3: 7.18 g /} ㎤, TiO 2: 4.26 g / ㎤, ZnO: 5.61 g / ㎤, SnO 2: 7.0 g / ㎤,

(For volume resistivity, surface resistivity)

Apparatus: Resistivity meter manufactured by NPS Σ-5 +

Method: DC 4 probe method

For the film, the surface resistivity is measured, and the volume resistivity is calculated by the following equation.

Volume resistivity (? Cm) = surface resistivity (? / Sq) 占 film thickness (cm)

(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: φ 4 inch

Substrate temperature: room temperature

(About crystallinity evaluation)

(UltimaIV, manufactured by Rigaku Corporation, Cu-K? Ray, tube voltage: 40 kV, current: 30 mA, 2? -? Reflection method, scanning speed: 8.0 DEG / min, sampling interval: 0.02 DEG). The crystallinity is evaluated by the value of the ratio I _MAX / I _{BG to} the background intensity I _BG for the maximum peak intensity I _MAX detected at 2? = 10 to 60 degrees. With respect to the background intensity, the use of (2θ = 1 ° ~ 10 ° as a range), low angle side and the average intensity of the high angle side peak region is not observed in the I _MAX. For example, I _BG = {(average intensity at 10 ° to 20 °) + (average intensity at 50 ° to 60 °)} / 2. As the judgment of the amorphous film, when it is I _MAX / I _BG ? 10, it is judged as the amorphous film.

(For the etching property)

The film-forming sample is evaluated as?, Which can be etched by the etching liquid (various kinds of acids), and?, Which is not etched or is excessively dissolved.

(For high temperature and high humidity resistance)

The sample was stored under the conditions of a temperature of 80 DEG C and a humidity of 80% for 48 hours, and then the optical constant and resistance were measured. When the characteristic difference was less than 10%

Example

The following is a description based on examples and comparative examples. Note that this embodiment is merely an example, and is not limited 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.

(Example 1)

In ₂ O ₃ powder, TiO ₂ powder, ZnO powder and SnO ₂ powder were prepared, and these powders were combined at the blending ratios shown in Table 1 and mixed. Was then subjected to the atmosphere of the mixed powder, and then calcining at a temperature of 1050 ℃, wet fine pulverization after (ZrO ₂ beads used) pulverized to less than the average particle size of 2 ㎛, and dried, sieve fractionation body of the scale 150 ㎛ . Thereafter, the pulverized powder was hot-pressed and sintered under the conditions of an argon atmosphere at a temperature of 1100 占 폚 and a pressure of 250 kgf / cm2. Thereafter, the sintered body was machined and finished in a target shape. Further, the composition of the sputtering target was analyzed, and it was confirmed that the sputtering target was equivalent to the blending ratio of the raw material powder.

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, and an Ar gas pressure of 0.5 Pa containing 2 vol% of oxygen. Further, the substrate was not heated during sputtering or annealed after sputtering.

Table 1 shows the above results. As shown in Table 1, the sputtering target had a relative density of 97.5% and a volume resistivity of 6.3 m? Cm, which enabled stable DC sputtering. Then, the thin film formed is sputtered, and a refractive index of 2.11 (wavelength 550 ㎚), the extinction coefficient is 0.03 (wavelength: 405 ㎚), a volume resistivity of 4.9 × 10 ^-1 Ω㎝, high refractive index, yet also electrically conductive film of high transmittance was obtained . As a result of the crystallization evaluation, it was confirmed that the film was an amorphous film with I _MAX / I _BG = 4 as shown in Fig.

(Example 2)

In ₂ O ₃ powder, TiO ₂ powder, ZnO powder and SnO ₂ powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. Was then subjected to the atmosphere of the mixed powder, and then calcining at a temperature of 1050 ℃, wet fine pulverization after (ZrO ₂ beads used) pulverized to less than the average particle size of 2 ㎛, and dried, sieve fractionation body of the scale 150 ㎛ . Thereafter, this fine pulverized 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 / 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.

Table 1 shows the above results. As shown in Table 1, the sputtering target had a relative density of 97.7% and a volume resistivity of 4.4 m? Cm, which enabled stable DC sputtering. The thin film formed by sputtering had a refractive index of 2.11 (wavelength: 550 nm), an extinction coefficient of 0.02 (wavelength: 405 nm), a volume resistivity of 9.8 Ω cm, and a conductive film having a high refractive index and a high transmittance. As a result of the crystallization evaluation, it was confirmed that the film was an amorphous film with I _MAX / I _BG = 4 as shown in Fig.

(Example 3)

In ₂ O ₃ powder, TiO ₂ powder, ZnO powder and SnO ₂ powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. Was then subjected to the atmosphere of the mixed powder, and then calcining at a temperature of 1050 ℃, wet fine pulverization after (ZrO ₂ beads used) pulverized to less than the average particle size of 2 ㎛, and dried, sieve fractionation body of the scale 150 ㎛ . Thereafter, this fine pulverized 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 / 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.

Table 1 shows the above results. As shown in Table 1, the sputtering target had a relative density of 99.5% and a volume resistivity of 3.7 m? Cm, which enabled stable DC sputtering. The thin film formed by sputtering had a refractive index of 2.10 (wavelength: 550 nm), an extinction coefficient of 0.02 (wavelength: 405 nm), a volume resistivity of 3.8 x 10 ² ? Cm, and a conductive film of high refractive index and high transmittance. As a result of the crystallization evaluation, I _MAX / I _BG = 4 was confirmed to be an amorphous film.

(Example 4)

In ₂ O ₃ powder, TiO ₂ powder, ZnO powder and SnO ₂ powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. Was then subjected to the atmosphere of the mixed powder, and then calcining at a temperature of 1050 ℃, wet fine pulverization after (ZrO ₂ beads used) pulverized to less than the average particle size of 2 ㎛, and dried, sieve fractionation body of the scale 150 ㎛ . Thereafter, this fine pulverized 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 / 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.

Table 1 shows the above results. As shown in Table 1, the sputtering target had a relative density of 100.9% and a volume resistivity of 1.5 m? Cm, which enabled stable DC sputtering. The thin film formed by sputtering had a refractive index of 2.11 (wavelength: 550 nm), an extinction coefficient of 0.02 (wavelength: 405 nm), a volume resistivity of 1.6 x 10 ³ ? Cm, and a conductive film of high refractive index and high transmittance. As a result of the crystallization evaluation, I _MAX / I _BG = 4 was confirmed to be an amorphous film.

(Example 5)

In ₂ O ₃ powder, TiO ₂ powder, ZnO powder and SnO ₂ powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. Was then subjected to the atmosphere of the mixed powder, and then calcining at a temperature of 1050 ℃, wet fine pulverization after (ZrO ₂ beads used) pulverized to less than the average particle size of 2 ㎛, and dried, sieve fractionation body of the scale 150 ㎛ . Thereafter, this fine pulverized 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 / 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.

Table 1 shows the above results. As shown in Table 1, the sputtering target had a relative density of 100.3% and a volume resistivity of 1.7 m? Cm, which enabled stable DC sputtering. The thin film formed by sputtering had a refractive index of 2.11 (wavelength: 550 nm), an extinction coefficient of 0.02 (wavelength: 405 nm), a volume resistivity of 3.6 x 10 ³ ? Cm, and a conductive film having a high refractive index and a high transmittance. As a result of the crystallization evaluation, I _MAX / I _BG = 4 was confirmed to be an amorphous film.

(Comparative Example 1)

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. Further, ZnO powder was not added. Next, the mixed powder was hot-pressed and sintered under an argon atmosphere at a temperature of 1050 DEG C and a pressure of 350 kgf / cm &lt; 2 &gt;. 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. However, in Comparative Example 1, the volume resistivity of the target (sintered body) was as high as 500 k? Cm and DC sputtering was impossible. Therefore, sputtering was performed using an RF sputter. The conditions of power and the like were the same as those of DC sputtering. As a result, the thin film formed by sputtering had a high volume resistivity of more than 1 MΩ cm, and a desired conductive film was not obtained.

(Comparative 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. Further, the SnO ₂ powder was not added. Next, the mixed powder was hot-pressed and sintered under an argon atmosphere at a temperature of 1050 DEG C and a pressure of 350 kgf / cm &lt; 2 &gt;. 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, as shown in Fig. 1, the thin film formed by sputtering has I _MAX / I _BG = 101, which is not an amorphous film, and has an extinction coefficient exceeding 0.05 (wavelength: 405 nm) Absorption of light occurs, and a desired high transmittance film can 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. Further, the SnO ₂ powder was not added. Next, this 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 &lt; 2 &gt;. 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 high volume resistivity of more than 1 M? Cm, and a desired conductive film could not be obtained. As a result of the crystallization evaluation, it was confirmed that the amorphous film was the amorphous film.

(Comparative Example 4)

In ₂ O ₃ powder, TiO ₂ powder, ZnO powder and SnO ₂ powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. Further, the content of In relative to Ti was more than specified. Next, the mixed powder was hot-pressed and sintered under an argon atmosphere at a temperature of 1050 DEG C and a pressure of 350 kgf / cm &lt; 2 &gt;. 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 more than 0.05 (wavelength: 405 nm), and a film with a desired transmittance was not obtained.

(Comparative Example 5)

In ₂ O ₃ powder, TiO ₂ powder, ZnO powder and SnO ₂ powder were prepared, and these powders were combined and mixed at the blending ratios shown in Table 1. Further, the total content of Zn and Sn relative to In and Ti was more than specified. Next, the mixed powder was hot-pressed and sintered under an argon atmosphere at a temperature of 1050 DEG C and a pressure of 350 kgf / cm &lt; 2 &gt;. Thereafter, the sintered body was machined and finished in a target shape. Next, using the finishing-processed target having a diameter of 6 inches, sputtering was carried out under the same conditions as in Example 1. As a result, the thin film formed by sputtering did not become an amorphous film, and had an extinction coefficient of more than 0.05 (wavelength: 405 nm), so that light absorption occurred in a low wavelength region and a desired high transmittance film was not obtained.

The thin film formed by the sputtering of the present invention forms a part of a thin film or optical disk structure for optical adjustment 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 volume resistivity value and a high density, which makes it possible to make a stable DC sputtering. It has a remarkable effect that the controllability of the sputter, which is a feature of the DC sputtering, can be facilitated, the deposition rate can be increased, and the sputtering efficiency can be improved. In addition, the quality of the film can be improved by reducing the particles generated during sputtering at the time of film formation.

Claims (12)

(In), titanium (Ti), zinc (Zn), tin (Sn) and oxygen (O) The content of Zn and Sn in the atomic ratio is 0.2? (Zn + Sn) / (In + Ti)? 1.5, and the content of Zn with respect to Sn satisfies the relation of 0.5? Zn / Sn? . The method according to claim 1,
And a relative density of 90% or more. The method according to claim 1,
And a volume resistivity of 10? Cm or less. 3. The method of claim 2,
And a volume resistivity of 10? Cm or less. (In), titanium (Ti), zinc (Zn), tin (Sn) and oxygen (O) The content of Zn and Sn in the atomic ratio is 0.2? (Zn + Sn) / (In + Ti)? 1.5, and the content of Zn with respect to Sn satisfies the relation of 0.5? Zn / Sn? . 6. The method of claim 5,
Wherein the refractive index at a wavelength of 550 nm is 2.05 or more. 6. The method of claim 5,
Wherein an extinction coefficient at a wavelength of 405 nm is 0.05 or less. The method according to claim 6,
Wherein an extinction coefficient at a wavelength of 405 nm is 0.05 or less. 9. The method according to any one of claims 5 to 8,
And a volume resistivity of 1 ㏁ or less. 9. The method according to any one of claims 5 to 8,
A membrane characterized by being amorphous. 10. The method of claim 9,
A membrane characterized by being amorphous. The method for producing a sintered body according to any one of claims 1 to 4, wherein the raw material powder is sintered under pressure in an inert gas or a vacuum atmosphere at a temperature of 900 ° C or higher and 1300 ° C or lower, or after press molding the raw material powder, Is sintered under normal pressure in an inert gas or a vacuum atmosphere at a temperature of 1000 ° C or higher and 1500 ° C or lower.

Images