KR20200019654A - Indium zinc oxide (izo) based sputtering target, and method for producing same - Google Patents

Abstract

The disclosed sputtering target is a sputtering target composed of In, Zn, and O, and an atomic ratio of Zn and In satisfies 0.05 <= Zn/(In + Zn) <= 0.30. Moreover, according to the present invention, standard deviation of bulk resistivity on the sputtering surface of the target is equal to or less than 0.1 mΩ·cm. The present invention provides a manufacturing method of an indium oxide-zinc oxide-based oxide (IZO) sintered body target, which has less warpage of a sintered body and wherein in-plane deviation of the bulk resistivity rate due to grinding for reducing the warpage is suppressed.

Description

Indium oxide-zinc oxide (IZO) sputtering target and manufacturing method thereof {INDIUM ZINC OXIDE (IZO) BASED SPUTTERING TARGET, AND METHOD FOR PRODUCING SAME}

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to an indium zinc oxide-based (IZO) sputtering target and a method for producing the same, and particularly, to a sputtering target suitable for formation of a film having a small difference in bulk resistivity in the sputtering surface of the target and a method for producing the same. will be.

Since the transparent conductive film which consists of several metal composite oxides has high electrical conductivity and visible light transmittance, it is a liquid crystal display device, a thin film electroluminescence display device, organic electroluminescence, a radiation detection apparatus, the transparent tablet of terminal equipment, and the dew condensation prevention of window glass. It is used for the various uses, such as a heat generating film, an antistatic film, the selective permeable film for solar collectors, and an electrode of a touch panel. Among the transparent conductive films made of such a metal composite oxide, the most prevalent one is a transparent conductive film made of indium tin oxide-tin oxide called ITO.

On the other hand, the demand for the transparent conductive film whose main component is a complex oxide of indium and zinc (called "IZO") which is larger than an ITO film is increasing. When manufacturing an IZO film | membrane, although the sintered compact sputtering target is used, this IZO sintered compact had the problem that a curvature generate | occur | produced in the sintering process. It is necessary to grind both sides of the target to be warped so as to have a flat surface in order to prepare the product shape, but the bulk resistivity in the target surface is greatly changed by the grinding process, and abnormal discharge or the like occurs during sputtering. There was a problem.

Next, the prior art regarding IZO sintered compact sputtering is demonstrated. Patent Literature 1 discloses mixing indium oxide and zinc oxide, and molding them by cold press and hydrostatic cold compression, and then heating and sintering at 1300 to 1500 ° C. in an oxygen atmosphere or in the atmosphere. In addition, Patent Document 2 discloses calcining only ZnO powder prior to mixing In ₂ O ₃ and the powder of ZnO.

Patent Document 3 describes that the indium oxide powder and the zinc oxide powder have specific properties. Moreover, when sintering IZO, patent document 4 makes it oxygen content 21% or more until reaching 1200 degreeC, and in 1200-1450 degreeC, it sinters in the atmosphere of less than 21% capacity of oxygen concentration, it is described. have. Patent Literature 5 describes controlling the grain size of the target by finely pulverizing the raw material powder.

However, under these conventional manufacturing processes, warpage occurred in the produced sintered compact with thermal expansion and thermal contraction by heating at the time of sintering. When processing the sintered compact with large warpage to a target shape, the difference in resistivity in the sputter | spatter surface of a target may become large. Such variation in resistivity in the target surface causes arcing (abnormal discharge) or the like at the time of sputtering, and has a problem of lowering the production yield of the product. In particular, with the recent large area of the sputtering target, the above problems have become remarkable.

Japanese Laid-Open Patent Publication 2001-131736 Japanese Patent Laid-Open No. 9-111444 Japanese Unexamined Patent Publication No. 2007-8780 Japanese Unexamined Patent Publication No. 2007-8772 International Publication No. 2001/038599

This invention is made | formed in order to solve the said subject, Comprising: It aims at providing the sputtering target and the manufacturing method which are small in the difference of the bulk resistivity in the sputter surface which can suppress generation | occurrence | production of arcing at the time of sputtering. . In particular, the object is to provide a sputtering target having a small in-plane difference in bulk resistivity even in a large area.

MEANS TO SOLVE THE PROBLEM As a result of earnestly researching in order to solve the said subject, as a result, when IZO shrinkage is started or started, it maintains temperature once, and makes small temperature distribution in a sintered compact, and can suppress a curvature amount of a sintered compact significantly by this. I found out. As a result, even if both surfaces were ground so that it might become a planar surface in order to prepare to a target shape, the knowledge that the sputtering target with a small difference of the in-plane bulk resistivity was acquired was obtained.

Based on such knowledge, this application provides the following invention.

1) As a sputtering target consisting of In, Zn and O, the atomic ratio of Zn and In satisfies 0.05 ≦ Zn / (In + Zn) ≦ 0.30, and the standard deviation of the bulk resistivity on the sputtering surface of the target is 1.0 mΩ. A sputtering target, which is cm or less.

2) The bulk resistivity is 1.0-10 mΩ * cm, The sputtering target as described in said 1) characterized by the above-mentioned.

3) The sputtering target according to the above 1) or 2), wherein the relative density is 98% or more.

4) The sputtering target according to any one of 1) to 3) above, wherein the area of the sputter face is 60000 mm 2 to 400000 mm 2.

5) A sintered body composed of In, Zn and O, wherein an atomic ratio between Zn and In satisfies 0.05 ≦ Zn / (In + Zn) ≦ 0.30, and the warpage amount is within 2.0 mm.

6) A method for producing a sputtering target made of an IZO sintered body, which is produced by sintering a molded body press-molded with a raw material powder, and in the step of raising the temperature from room temperature to the sintering temperature, the intermediate holding temperature is set to 600 to 800 ° C, It consists of the process which hold | maintains for 10 hours, the process of heating up at 0.2-2.0 degreeC / min from the holding temperature to the sintering temperature in this middle, the process of making sintering temperature into 1350-1500 degreeC, and sintering holding time in 1 to 100 hours. The manufacturing method of the sputtering target characterized by the above-mentioned.

7) Sintering temperature is 1380-1420 degreeC, The manufacturing method of the sputtering target as described in said 6) characterized by the above-mentioned.

8) Sintering holding time is sintered for 5 to 30 hours, The manufacturing method of the sputtering target as described in said 6) or 7) characterized by the above-mentioned.

9) The method for producing a sputtering target according to any one of 6) to 8), wherein the temperature is decreased to 1.0 to 5.0 ° C / min.

10) The method for producing a sputtering target according to any one of 6) to 9), wherein the temperature is raised from 0.5 to 1.5 ° C / min from the holding temperature to the sintering temperature.

In the manufacturing method of an indium zinc oxide type | system | group oxide (IZO) sintered compact, this invention finds that it is effective to reduce curvature to hold | maintain at a specific temperature among manufacturing conditions different from the conventional, ie, sintering conditions, and sputter surface It is possible to produce a target having a small difference in bulk resistivity in the interior, and as a result, there is little occurrence of arcing and the like, thereby enabling excellent sputtering and improving the characteristics of the formed film. The present invention is particularly effective in a large-area IZO sputtering target.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the measuring point of the bulk resistivity of the sputtering target (square) of this invention.
It is a figure which shows the measuring point of the bulk resistivity of the sputtering target (disk type) of this invention.
It is a schematic diagram which shows the measurement of the curvature amount of the sputtering target of this invention.

The component composition of the sputtering target of this invention consists of indium (In), zinc (Zn), and oxygen (O), and satisfy | fills the conditions which the atomic ratio of Zn and In is 0.05 <= Zn / (In + Zn) <= 0.30. will be. The target of the present invention is mainly composed of a complex oxide of indium and zinc, but may contain an oxide of indium oxide or zinc oxide alone. Moreover, you may contain another element in the range which does not impair the characteristic of this invention. The atomic ratio of Zn is determined from the viewpoint of conductivity and the like of the film formed by using the target, and when it exceeds this range, desired characteristics are not obtained.

The present invention is characterized in that the standard deviation of the bulk resistivity on the sputtering surface of the sputtering target is 1.0 mΩ · cm or less. In the case where the warpage of the sintered body is large, the variation in the bulk resistivity of the sputter face of the target becomes large, and thus there is a problem of inhibiting the uniformity of the formed film properties (particularly film resistance). In this invention, curvature of a sintered compact is remarkably reduced by adjusting sintering conditions, thereby making it possible to reduce the standard deviation of the bulk resistivity in sputter surface to 1.0 m (ohm) * cm or less. In addition, a sputter surface means the surface sputtered by a sputter apparatus as a result of grinding a sintered compact and processing into a sputtering target.

The bulk resistivity of the present invention is preferably 1.0 mΩ · cm or more and 10 mΩ · cm or less. When bulk resistivity is high, sputter discharge may become unstable. The bulk resistivity of the present invention measures at least 16 points (for square targets) or 9 points or more (for discoid targets) at equal intervals on the sputter face of the target by four probe method, and the average value and standard deviation are measured. Calculate. For example, as shown to FIG. 1, 2, the site | part of 15 mm in length and width is measured 3 times at equal intervals of 50 mm-60 mm from the target part 20 mm or more inside, and the average of the site | part Let it be bulk resistivity. However, when the area of a target is small, a measurement score is secured 9 or more points or 16 points or more by narrowing a measurement space | interval. In addition, when measuring the bulk resistivity of a target, you may grind as needed.

In general, the larger the area of the sintered body, the larger the amount of warpage. This invention can suppress the curvature amount within 2.0 mm even if it is a sintered compact of large area. It is characterized by the above-mentioned. This invention is especially excellent in the point which can make the resistivity difference in a sputter surface fall in the said range, even if the area in the sputter surface of a target is 60000 mm <2> -400000 mm <2>. Here, a laser displacement sensor is used for the measurement of the warp, and the height is measured while scanning one surface of the sintered body with a laser as shown in FIG. 2 in accordance with the size of the sintered body using the laser as a probe. . And the difference of the maximum height and minimum height in surface inside is made into the largest deflection amount.

Moreover, the sputtering target of this invention is a relative density being 98% or more, It is characterized by the high density. A high density target can reduce the particle | grains at the time of sputtering, and can form the film | membrane with favorable characteristic. The relative density is represented by (the actual density of the sintered body measured by the Archimedes method) / (theoretical density calculated from the composition of the oxide) x 100 = relative density (%). Here, the theoretical density calculated from the composition of the oxide is, the theoretical density calculated from the elements constituting the material, for example indium oxide (In ₂ O ₃₎ powder, a zinc oxide (ZnO) powder as a raw material oxide and oxide When the weight ratio of indium: zinc oxide is 90 wt%: 10 wt%, the theoretical density calculated from the composition of the oxide = (theoretical density of indium oxide x 90 + theoretical density of zinc oxide x 10) / 100 (g / cm 3) Calculated by

The indium oxide-zinc oxide-based oxide (IZO) sintered compact target of this invention can be produced through the processes of mixing, grinding | pulverizing, shaping | molding, and sintering a raw material hereafter.

(Conditions for Mixing, Grinding, Granulating, and Forming Raw Materials)

Indium oxide (In ₂ O ₃ ) powder and zinc oxide (ZnO) powder are prepared as raw material powders. It is preferable to use a raw material powder whose specific surface area is about 5 m <2> / g.

Specifically, indium oxide powder has a bulk density of 0.5 to 0.7 g / cm 3, median diameter (D ₅₀ ) of 1.0 to 2.1 μm, specific surface area of 4.0 to 5.7 m 2 / g, and zinc oxide powder of 0.2 to 0.2 m. 0.6 g / ㎤, median diameter _{(D 50): 1.0 ~ 2.5} ㎛, specific surface area: use 3.0 ~ 6.0 ㎡ / g.

Next, after mixing each raw material powder to a desired composition ratio, mixed grinding is performed. There are various methods for the pulverization method depending on the particle size and the material to be pulverized, but a wet medium stirring mill such as a bead mill is suitable. This is forcibly stirring the slurry which disperse | distributed the powder body to water with the grinding media, such as zirconia and alumina which are high hardness materials, and can obtain a grinding powder with high efficiency. However, at this time, since the grinding medium also wears, the grinding powder itself is mixed as impurities in the grinding powder, so that a long time treatment is not preferable.

When the grinding amount is defined as the difference of the specific surface area before and after grinding, in the wet medium stirring mill, the grinding amount is almost proportional to the input energy to the powder. Therefore, when carrying out grinding | pulverization, it is important for a wet medium stirring mill to manage integration power. The difference (ΔBET) of the specific surface area before and after grinding is 0.5 to 3.0 m 2 / g, and the median diameter (D ₅₀ ) after grinding is set to 1.0 µm or less.

Next, the finely ground slurry is granulated. This is to improve the fluidity of the powder by granulation, so that the powder is uniformly filled in the mold during press molding of the next step, and a homogeneous molded body is obtained. Although there are various methods of granulation, one method of obtaining granulated powder suitable for press molding is a method of using a spray drying apparatus (spray dryer). This can continuously obtain a 10-500 micrometer spherical granulated powder by making a powder into a slurry, disperse | distributing as a droplet in hot air, and instantaneously drying.

In the drying furnace by the spray dryer, it is important to manage the inlet temperature and the outlet temperature of the hot air. If the temperature difference between the inlet and the outlet is large, the amount of drying per unit time increases and productivity is improved. However, if the inlet temperature is too high, the powder and the added binder may be deteriorated by heat, and desired characteristics may not be obtained. Moreover, when an exit temperature is too low, granulated powder may not dry enough.

Moreover, molded body strength can be improved by adding a binder, such as polyvinyl alcohol (PVA), to a slurry and containing it in granulated powder. The addition amount of PVA adds 50-250 cc / kg of PVA 6 wt% containing aqueous solution with respect to raw material powder. In addition, by adding a plasticizer suitable for the binder, the crush strength of the granulated powder during press molding can be adjusted. Moreover, there also exists a method of improving a molded object strength by adding a small amount of water to the granulated powder obtained, and making it wet.

Next, press molding is performed. The granulated powder is filled into a mold, and the pressure of 400-1000 kgf / cm <2> is hold | maintained for 1-3 minutes and shape | molding. If the pressure is less than 400 kgf / cm 2, a molded product having sufficient strength and density cannot be obtained, and at a pressure of 1000 kgf / cm 2 or more, when the molded body is taken out of the mold, the molded body itself may be destroyed due to deformation due to release from pressure. It is not preferable in production.

(Sintering process)

Using an electric furnace, the molded body is sintered in an oxygen atmosphere to obtain a sintered body. It raises to sintering temperature 1350-1500 degreeC. During the temperature increase, a holding step is introduced in order to reduce the temperature distribution in the sintered compact. The holding temperature may be introduced at a temperature of 600 to 800 ° C. in order to reduce the temperature distribution in the sintered body in the temperature range before the reaction starts. If it is less than 600 degreeC, temperature is too low and an effect does not appear, and when it is higher than 800 degreeC, since reaction has already advanced to some extent, the effect of curvature reduction is not acquired. The holding time is 1 to 10 hours, preferably 4 to 6 hours. If the holding time is too short, the progress of the reaction cannot be sufficiently suppressed. On the other hand, if the holding time is too long, the productivity is lowered, which is not preferable.

And it raises at 0.2-2.0 degreeC / min from the holding temperature to the sintering temperature in the middle. If the temperature increase rate from the holding temperature to the sintering temperature is smaller than 0.2 ° C / min, the time may be unnecessarily required to reach a predetermined temperature, the density may not increase, and the temperature increase rate is higher than 2.0 ° C / min. The temperature distribution in the sintered compact does not become small, and nonuniformity occurs or the sintered compact cracks. Preferably, it is 0.5-1.5 degreeC / min.

Sintering temperature shall be 1350-1500 degreeC, hold | maintain for about 1 to 100 hours, and it temperature-falls at a furnace cooling or temperature-fall rate 1.0-5.0 degreeC / min after that. If the sintering temperature is lower than 1350 ° C., a high density sintered body cannot be obtained. Moreover, at the sintering temperature of 1500 degreeC or more, since the zinc oxide volatilizes, there also exists a cost problem that a sinter density decreases and a composition deviation arises, and furnace heater lifetime falls, so it is preferable to set an upper limit to 1500 degreeC. Do. Preferably, it is 1380-1420 degreeC. When the holding time at the sintering temperature is shorter than 1 hour, the sintering does not proceed sufficiently, and the density of the sintered compact does not sufficiently increase or the sintered compact is bent. Even if the holding time exceeds 100 hours, unnecessary energy and time inefficiency occur, which is undesirable in production. Preferably it is 5 to 30 hours.

Example

Next, the Example of this invention is described. In Examples and Comparative Examples, the step of producing a molded article press-molded the raw material powder of the indium zinc oxide-based oxide (IZO) sintered body is carried out under the conditions described in the above identification numbers, Further, the sintering step was carried out by appropriately set within the range of the conditions described in the identification number-identification number. The composition of each sintered compact is as showing in Table 1.

In the arcing test in Examples and the like, a magnetron sputtering device (model number: BSC7011) manufactured by Cyntron was used in an argon atmosphere under the conditions of DC power density: 2.3 W / cm 2, gas pressure: 0.6 Pa, and a gas flow rate of 300 sccm. Sputtering was performed continuously for 35 hours to investigate the state of occurrence of arcing. As for the detection of arcing, the number of times of arcing (micro arc) occurrence (times) was measured using a landmark technology micro arc monitor (MAM genesis). The arcing criterion counts arcing with a detection voltage of 100 V or more and emission energy (sputtering voltage at the time of arc discharge x sputter current x generation time) of 20 mJ or less, and if it is 10 times or less, ○ It was made into x.

(Example 1)

In Example 1, maximum sintering temperature was 1400 degreeC, sintering holding time was 10 hours, and middle holding temperature was 800 degreeC. As a result, the density of the sintered compact was 98.41%, and the maximum deflection value was 1.39 mm. Moreover, in order to prepare the sintered compact in target shape, both surfaces were ground so that it might become planar, As a result, the bulk resistivity of the target was 2.43 m (ohm) * cm, and the standard deviation was 0.78 m (ohm) * cm. In Example 1, favorable results were obtained that the warpage amount of the sintered compact was small and the variation in the bulk resistivity of the target was small. Moreover, as a result of sputtering the target produced in this way, generation | occurrence | production of arcing was hardly seen. The above results are shown in Table 1.

(Examples 2 to 15)

In Examples 2-15, the conditions of the composition of a sintered compact, maximum sintering temperature, sintering holding time, middle holding temperature, middle holding time, intermediate holding temperature to sintering holding temperature, and the conditions of the area of a sintered compact were changed, respectively. As a result, as shown in Table 1, all the sintered bodies had a density of 98% or more, and the maximum warpage value was within 2.0 mm. Moreover, in order to prepare the sintered compact in target shape, both surfaces were ground so that it might become planar, As a result, the bulk resistivity of the target was 1.0-10.0 m (ohm) -cm, The standard deviation was within 1.0 m (ohm) * cm. In Examples 2-15, the favorable result that the curvature amount of a sintered compact was small and the variation of the bulk resistivity of a target is small was obtained. Moreover, as a result of sputtering these targets, generation | occurrence | production of arcing was hardly seen.

(Comparative Example 1)

In Comparative Example 1, the maximum sintering temperature was 1400 ° C., the sintering holding time was 10 hours, and the middle holding was not performed. As a result, the maximum curvature value of the sintered compact became 2.30 mm. Moreover, in order to prepare the sintered compact in target shape, both surfaces were ground so that it might become a flat surface, and as a result, the standard deviation of the bulk resistivity of a target was 1.40 m (ohm) * cm. In Comparative Example 1, a result was obtained in which the amount of warpage of the sintered body was large and the variation in the bulk resistivity of the target was large. Moreover, as a result of sputtering the target thus produced, there were many occurrences of arcing.

(Comparative Example 2)

In Comparative Example 2, the maximum sintering temperature was 1400 ° C, the sintering holding time was 10 hours, and the middle holding temperature was lowered to 500 ° C. As a result, the maximum curvature value of the sintered compact was 2.06 mm. Moreover, in order to prepare the sintered compact in target shape, both surfaces were ground so that it might become a flat surface, and as a result, the standard deviation of the bulk resistivity of the target was 1.18 mΩ * cm. In Comparative Example 2, a result was obtained in which the amount of warpage of the sintered body was large and the variation in the bulk resistivity of the target was large. Moreover, as a result of sputtering the target thus produced, there were many occurrences of arcing.

(Comparative Example 3)

In Comparative Example 3, the maximum sintering temperature was 1400 ° C, the sintering holding time was 10 hours, and the middle holding temperature was high at 900 ° C. As a result, the maximum curvature value of the sintered compact became 2.14 mm. Moreover, in order to prepare the sintered compact in target shape, both surfaces were ground so that it might become planar, and the standard deviation of the bulk resistivity of a target was 1.24 m (ohm) * cm. In Comparative Example 3, a result was obtained in which the amount of warpage of the sintered body was large and the variation in the bulk resistivity of the target was large. Moreover, as a result of sputtering the target thus produced, there were many occurrences of arcing.

(Comparative Example 4)

In Comparative Example 4, the maximum sintering temperature was 1400 ° C, the sintering holding time was 10 hours, and the middle holding temperature was high at 1100 ° C. As a result, the maximum curvature value of the sintered compact became 2.11 mm. Moreover, in order to prepare the sintered compact in target shape, both surfaces were ground so that it might become a flat surface, and as a result, the standard deviation of the bulk resistivity of the target was 1.11 mΩ * cm. In Comparative Example 4, a result was obtained in which the amount of warpage of the sintered body was large and the variation in the bulk resistivity of the target was large. Moreover, as a result of sputtering the target thus produced, there were many occurrences of arcing.

(Comparative Example 5)

In Comparative Example 5, the maximum sintering temperature was 1400 ° C, the sintering holding time was 10 hours, the middle holding temperature was 800 ° C, and the temperature increase rate from the middle holding temperature to the maximum sintering temperature was accelerated to 5 ° C / min. As a result, the maximum curvature value of the sintered compact became 2.23 mm. Moreover, in order to prepare the sintered compact in target shape, both surfaces were ground so that it might become a flat surface, and as a result, the standard deviation of the bulk resistivity of the target was 1.26 mΩ * cm. In Comparative Example 5, a result was obtained in which the amount of warpage of the sintered body was large and the variation in the bulk resistivity of the target was large. Moreover, as a result of sputtering the target thus produced, there were many occurrences of arcing.

(Comparative Example 6)

In Comparative Example 6, the maximum sintering temperature was 1400 ° C., the sintering holding time was 10 hours, the middle holding temperature was 800 ° C., and the middle holding time was shortened to 1 hour. As a result, the maximum curvature value of the sintered compact became 2.31 mm. Moreover, in order to prepare the sintered compact in target shape, both surfaces were ground so that it might become planar, and the standard deviation of the bulk resistivity of a target was 1.31 m (ohm) * cm. In Comparative Example 6, a result was obtained in which the amount of warpage of the sintered body was large and the variation in the bulk resistivity of the target was large. Moreover, as a result of sputtering the target thus produced, there were many occurrences of arcing.

(Comparative Example 7)

In the comparative example 7, the holding | maintenance temperature was 800 degreeC and the highest sintering temperature was made high at 1600 degreeC. As a result, the maximum curvature amount of the sintered compact was 2.33 mm, and the relative density was 97.5%. Moreover, in order to prepare the sintered compact in target shape, both surfaces were ground so that it might become a flat surface, and as a result, the standard deviation of the bulk resistivity of the target was 1.42 mΩ * cm. In Comparative Example 7, thus, a large amount of warpage of the sintered compact and a large variation in the bulk resistivity of the target were obtained. Moreover, as a result of sputtering the target thus produced, there were many occurrences of arcing.

(Comparative Example 8)

In the comparative example 8, middle hold | maintenance temperature was 800 degreeC and the highest sintering temperature was made high at 1500 degreeC. As a result, the maximum curvature amount of the sintered compact was 2.37 mm. Moreover, in order to prepare the sintered compact in target shape, both surfaces were ground so that it might become planar, and the standard deviation of the bulk resistivity of a target was 1.53 m (ohm) * cm. In Comparative Example 8, a result was obtained in which the amount of warpage of the sintered body was large and the variation in the bulk resistivity of the target was large. Moreover, as a result of sputtering the target thus produced, there were many occurrences of arcing.

As mentioned above, this invention has the outstanding effect that a sintered compact with a small curvature can be manufactured in a favorable yield according to the sintering conditions different from the past, and this can improve productivity remarkably. Moreover, this invention has the outstanding effect that the dispersion | variation in the bulk resistivity of the sputter | spatter surface of the target after processing the sintered compact can be made small by reducing the curvature of the sintered compact, and can form a film | membrane with a uniform characteristic. The sputtering target of this invention is useful for formation of the transparent conductive film used for a liquid crystal display device, a thin film electroluminescence display device, organic EL, etc.

Claims (3)

As a sputtering target consisting of In, Zn, O,
The atomic ratio of Zn and In satisfies 0.05 ≦ Zn / (In + Zn) ≦ 0.30, the area of the sputter face of the target is 60000 mm 2 or more, and the standard deviation of the bulk resistivity on the sputter face is 1.0 mΩ · cm or less The relative density is 98% or more, the sputtering target characterized by the above-mentioned. The method of claim 1,
The bulk resistivity is 1.0-10 mΩ * cm, The sputtering target characterized by the above-mentioned. The method according to claim 1 or 2,
The sputtering target is characterized in that the area of the sputter face is 60000 mm 2 to 400000 mm 2.

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