Sputtering target and oxide thin film

Abstract

The present invention provides an indium gallium zinc (IGZO) oxide-based sputtering target and an oxide thin film formed therefrom, wherein the sputtering target can ensure a fine and uniform grain diameter due to the precise control of metal dopant components and the amounts thereof, and has excellent surface profile characteristics even after usage of a predetermined range.

Description

Sputtering targets and oxide films

[0001] The present invention relates to a sputtering target and an oxide thin film used in a TFT structure of an LCD and / or an OLED, and more specifically, to an indium gallium zinc oxide (IGZO)-based sputtering target and an oxide thin film formed therefrom, which can secure a fine and uniform crystal grain size by precisely controlling the components and content of a metal dopant and have excellent surface roughness characteristics even after using a certain amount of the target.

[0002]

[0003] Currently, thin-film transistors (TFTs) are manufactured using oxide semiconductors, and their application in electronic and optical devices is attracting attention. For example, oxide thin films containing indium, gallium, and zinc are used as the active layers of thin-film transistors. However, high indium content in the thin film can lead to reduced device stability. While reducing the indium content or increasing the amounts of gallium and zinc can improve device stability, exceeding these thresholds results in target resistivity that is too high, making DC sputtering impossible.

[0004]

[0005] Meanwhile, the inventors of the present invention have discovered that when a metal dopant of a specific component is included in an optimal content in an indium gallium zinc (IGZO) oxide sintered body, not only can an oxide sputtering target having a fine and uniform average grain size be secured, but also an indium gallium zinc (IGZ)-based oxide sputtering target having excellent surface roughness characteristics can be formed even after a certain amount of the target is consumed.

[0006] Accordingly, the present invention has as a technical object the provision of an IGZO-based oxide sputtering target having an optimization of the crystal grain size within the target and an ability to suppress the growth of surface roughness even after consuming a predetermined range, and an oxide thin film formed therefrom.

[0007] Other objects and advantages of the present invention can be more clearly explained by the detailed description of the invention and the claims below.

[0008]

[0009] In order to achieve the above-mentioned technical task, the present invention provides a sputtering target including a sintered body of an oxide containing indium (In), gallium (Ga), zinc (Zn), and a metal (M), wherein the metal (M) includes at least one selected from the group consisting of Al, Sn, Hf, Ti, and Zr, the content of the metal (M) is less than 5 wt% based on 100 wt% of the total metal excluding oxygen, and the surface roughness of the consumed surface of the target is 1.2 times or less compared to the grain size of the non-consumed target based on a sputtering target consumed by 30 volume%.

[0010] In one embodiment of the present invention, the metal may be included in an amount of 3 wt% or less relative to 100 wt% of the total metal excluding oxygen.

[0011] In one embodiment of the present invention, the average grain size included in the sintered body may be 1 to 25 μm.

[0012] In one embodiment of the present invention, based on a target consumed by 30% by volume, the surface roughness of the consumed surface of the target may be 30 μm or less.

[0013] In one embodiment of the present invention, the sputtering target is 3.0 × 10 -3 4.99 × 10 -3 It can have a resistivity of Ωcm and a relative density of 98.0 to 99.9%.

[0014] In one embodiment of the present invention, when the sputtering target is deposited by applying DC power of 200 W under an inert atmosphere, the current generated in the sputtering target is 0.30 A / cm 2 It may be less than.

[0015] In one embodiment of the present invention, the sputtering target does not generate cracks or fractures when deposited by applying DC power of 200 W under an inert atmosphere.

[0016] The present invention also provides an oxide thin film formed from the aforementioned sputtering target.

[0017] In one embodiment of the present invention, the atomic % ratio of indium (In): gallium (Ga): zinc (Zn) in the oxide thin film may be in the range of 1:1:1.

[0018] In one embodiment of the present invention, the average particle size of the crystal phase included in the oxide thin film may be 5 to 30 μm.

[0019] In one embodiment of the present invention, the thickness of the oxide thin film may be 5 to 50 nm.

[0020] In one embodiment of the present invention, the oxide thin film may have an average reflectivity of 25% or less at a wavelength of 360 to 740 nm, and a sheet resistance of 300 to 1,300 Ω / sq at a thickness of 100 to 500 Å.

[0021] In addition, the present invention provides a thin film transistor including the above-described oxide thin film.

[0022]

[0023] According to one embodiment of the present invention, by adopting a specific metal dopant and precisely controlling the content thereof within a predetermined range, a fine and uniform crystal grain size within a target can be secured, and even after the target is consumed within a predetermined range, growth of surface roughness can be suppressed, thereby providing an indium gallium zinc (IGZO) oxide sputtering target having excellent surface roughness characteristics and an oxide thin film formed therefrom.

[0024] Accordingly, the indium gallium zinc (IGZO) sputtering target according to the present invention can simultaneously implement excellent thin film properties, low resistance, and low reflection properties, and thus can be usefully applied to the formation of electrodes or wiring used in TFT structures of LCDs and OLEDs.

[0025] The effects according to the present invention are not limited to those exemplified above, and more diverse effects are included in this specification.

[0026]

[0027] Figure 1 is a photograph of the oxide sputtering targets of Example 1 and Comparative Examples 1 to 3 after consuming 30% or more of the volume of each.

[0028]

[0029] Hereinafter, the present invention will be described in detail.

[0030] All terms (including technical and scientific terms) used in this specification may be used with meanings commonly understood by those of ordinary skill in the technical field to which the present invention pertains. Furthermore, terms defined in commonly used dictionaries should not be interpreted ideally or excessively unless explicitly and specifically defined otherwise.

[0031] Furthermore, throughout the specification, when a part is said to "include" a component, unless otherwise specifically stated, this does not exclude other components but rather means that other components may be included. Furthermore, throughout the specification, the terms "above" or "on" include not only cases where the target part is located above or below it, but also cases where there is another part in between, and do not necessarily mean that the target part is located above it in the direction of gravity. In addition, terms such as "first" and "second" in the specification do not indicate any arbitrary order or importance, but are used to distinguish between components.

[0032]

[0033] <IGZO계 산화물 소결체 및 스퍼터링 타겟>

[0034] An example of the present invention is an IGZO-based oxide sintered body used in a TFT structure of an LCD and / or OLED and a sputtering target including the same.

[0035] For example, the sputtering target comprises a sintered body of an oxide containing indium (In), gallium (Ga), zinc (Zn), and a metal (M), wherein the specific metal (M) is contained in a predetermined amount.

[0036] The sputtering target according to the present invention is an oxide containing indium-gallium-zinc (IGZO) as its main component. The components, content, and composition of this oxide are not particularly limited and can be appropriately adjusted within a conventional range known in the art. For example, the atomic % ratio of indium (In): gallium (Ga): zinc (Zn) is preferably substantially in the range of 1:1:1.

[0037] In addition, the metal component included in the sputtering target according to the present invention includes at least one selected from the group consisting of Al, Sn, Hf, Ti, and Zr. Specifically, it is preferable to use at least one of Al and Sn.

[0038] The above metal (M) may be included in an amount of less than 5 wt% based on 100 wt% of the total metal excluding oxygen, specifically 3% or less, and more specifically 1.5% or less. For example, the formula for the metal (M) content based on 100 wt% of the total metal excluding oxygen, for example (In+Ga+Zn+M) / (In+Ga+Zn), may be less than 5 wt%, or 3% or less, or 1.05% or less.

[0039] When the aforementioned specific metal is included in a predetermined amount, the sputtering target of the present invention can secure a fine and uniform crystal grain size within the IGOZ target, and can secure excellent surface roughness characteristics by suppressing the growth of surface roughness even after the target is consumed within a predetermined range. In addition, the addition of the specific metal can enhance the high-density, chemical resistance, and heat resistance characteristics of the oxide thin film.

[0040] In particular, the sputtering target of the present invention composed of the aforementioned composition has a finer average grain size (D50) compared to a conventional control group not including a metal (M) dopant and a control group including the same metal (M) dopant but having a content value outside the aforementioned range, and has a smaller difference in surface roughness before and after sputtering of the target, thereby enabling uniform surface characteristics and excellent thin film characteristics. That is, the growth of grains within a sintered body is suppressed by the metal (M) dopant included in a specific content range, thereby ensuring homogeneity and high quality of the thin film.

[0041] For example, the average grain size (D50) included in the sintered body of the sputtering target may be 1 to 25 μm, specifically 3 to 20 μm, and more specifically 5 to 15 μm.

[0042] As another specific example, based on a 30 volume % consumed target, the surface roughness of the consumed side of the target may be 1.2 times (e.g., 120%) or less than the grain size of the unconsumed target, more specifically 1.1 times or less, and more specifically 0.9 times or less.

[0043] In another specific example, the difference in surface roughness (Ra) of the oxide sintered target before and after sputtering may be 3 μm or less, and more specifically 0.5 to 3 μm. For example, the surface roughness (Ra) of the consumed surface of the 30 volume% consumed target may be 30 μm or less, and specifically 20 μm or less, and more specifically 15 μm or less.

[0044] In addition, the sputtering target according to the present invention promotes composition optimization, so that when the IGZO target is deposited by applying a predetermined range of power (e.g., DC power of 200 W) under an inert atmosphere, the current generated in the sputtering target is controlled to be below the predetermined range, thereby suppressing the growth of surface roughness without generating separate nodules or foreign substances, thereby securing excellent surface roughness characteristics. In addition, since cracks or defects on the surface do not occur, uniform surface characteristics can be secured.

[0045] For example, when the sputtering target is deposited by applying DC power of 200 W under an inert atmosphere, the current generated in the sputtering target is 0.30 A / cm 2 less than, more specifically, 0.1 to 0.29 A / cm 2 It could be.

[0046] As another specific example, the sputtering target can maintain fine uniform surface characteristics without cracks or defects occurring during deposition by applying DC power of 200 W under an inert atmosphere.

[0047] The aforementioned sputtering target is based on when 50 wt% of the total target weight (e.g., 100 wt%) is consumed, or when 30 vol% of the total 100 volume% of the target is consumed.

[0048] As another specific example, the sputtering target has a relative density of 98% or more and a density of 1×10 -3 1×10 -4 It can have resistivity characteristics of Ωcm, and specifically, a relative density of 98.0 to 99.9% and a specific gravity of 3.0 × 10 -3 4.99 × 10 -3 It can have a resistivity characteristic of Ωcm.

[0049] Meanwhile, the present invention specifically exemplifies the aforementioned components as metal (M) components, but is not limited thereto, and the use of conventional metals capable of implementing fine grain size optimization characteristics also falls within the scope of the present invention.

[0050] <IGZO 타겟의 제조 방법>

[0051] Hereinafter, a method for manufacturing an IGZO-based sputtering target according to one embodiment of the present invention will be described. However, the present invention is not limited to the following manufacturing method, and each process step may be modified or selectively combined and performed as needed.

[0052] The present invention relates to the manufacture of a sputtering target, wherein raw material powders of metal or ceramic are heat-treated to form a single mass. For example, when manufacturing an oxide sintered body and a sputtering target, the raw material powders of metal or ceramic are made of indium oxide powder, gallium oxide powder, and zinc oxide powder as base materials, and at least one type of metal (M) dopant is added in a specific content range, mixed, and then the final sputtering target is formed.

[0053] One example of the above manufacturing method may comprise the steps of (i) preparing and mixing raw material powders containing indium oxide, gallium oxide, zinc oxide, and at least one metal according to a target composition ('step S10'); (ii) manufacturing a molded body using the mixed raw material powders ('step S20'); and (iii) heat-treating the molded body at 1,400 to 1,600°C for 10 to 40 hours under atmospheric pressure or an oxygen atmosphere to manufacture a sintered body ('step S30').

[0054] Hereinafter, the above manufacturing method is explained in detail by each process step.

[0055] (i) Preparation of raw powder ('Step S10')

[0056] In the above step S10, a spheroidized raw material powder containing indium oxide, tin oxide, zinc oxide, and at least one metal ion is prepared.

[0057] Here, the metal ion may be at least one of Al, Sn, Hf, Ti, and Zr. Specifically, powders containing each element are weighed to match the target composition, then placed in a mixer and ground and mixed with a bead mill to produce a slurry.

[0058] When mixing the respective raw material powders, conventional additives known in the art, such as binders, dispersants, and antifoaming agents, may be additionally included as needed. At this time, the amount of additives used may be appropriately adjusted within a conventional range known in the art, and for example, 0.01 to 10 wt% may be used relative to the total weight of powders in the slurry (e.g., 100 wt%).

[0059] Here, a dispersant is added to finely disperse the crushed raw material particles while maintaining a stable dispersion within the solution. A usable dispersant is polyacrylic acid (PAA), and can be used in an amount of 0.5 to 3.0 wt% relative to the powder weight in the slurry.

[0060] Additionally, silicone oil may be used as a defoaming agent to remove bubbles within the slurry. The defoaming agent may be used in an amount of 0.001 to 0.1 wt% relative to the total weight of the raw material powder.

[0061] Mixing and grinding of raw material powders are not particularly limited and can be performed using a conventional ball mill, attraction mill, bead mill, etc. known in the art. For example, a slurry prepared by mixing indium oxide, tin oxide, zinc oxide, one or more types of metal powders, and conventional additives as needed is milled and dried to prepare a dry powder.

[0062] The viscosity of the slurry obtained from the bead mill is preferably maintained at 200 to 500 cps, but is not limited thereto. Furthermore, the slurry obtained from the bead mill can be spray-dried using a powder spheroidizing (spray dryer) device to obtain a spheroidized dry powder.

[0063] If necessary, sieving may be performed to homogenize the spheroidized powder to obtain the final powder. For example, sieving may be performed using a sieve with a mesh size of 120 or less.

[0064] (ii) Manufacturing of molded body ('Step S20')

[0065] The above step S20 is a step of manufacturing a molded body using the prepared raw material powder. More specifically, the raw material powder is fed into a molding machine and molded to manufacture a molded body having a predetermined specification or shape.

[0066] To increase the density of the molded body, the molding process can be performed at least once, or more specifically, twice. For example, the first molding process may involve feeding spheroidized powder into a single-axis press to produce the primary molded body, while the second molding process may utilize a hydrostatic press (CIP) machine.

[0067] The conditions in the above first molding process are not particularly limited and can be appropriately adjusted within the range of common conditions known in the art. For example, the pressurization conditions in the first molding step are performed in the range of 50 to 100 MPa per unit area. In addition, the molding density of the molded body obtained in the first molding step can be adjusted to 45 to 55%. If the molding density is low, the sintering driving force is low, which increases the sintering time or temperature, and if the molding density is high, cracks may occur in the molded body.

[0068] Afterwards, the secondary molding process is performed by molding the molded body formed in the primary mold using an isotropic pressing (CIP) machine, thereby obtaining a molded body having uniform isotropy. The pressurizing conditions in the secondary molding step can be appropriately controlled within the range of typical conditions known in the art. For example, the pressurizing conditions in the secondary molding step can be in the range of 2,000 to 2,500 MPa per unit area. The molding density of the molded body produced in the secondary molding step can be 60 to 65%.

[0069] (iii) Manufacturing of sintered body ('S30 stage')

[0070] In the above step S30, the manufactured secondary molded body is sintered under predetermined conditions to manufacture an oxide semiconductor sintered body.

[0071] At this time, sintering conditions are not particularly limited and can be appropriately adjusted within the range of commonly known conditions in the art. For example, a temperature of 1400 to 1600°C can be maintained for 10 to 40 hours in an air or oxidizing atmosphere. At this time, the atmosphere gas is air or oxygen, which serves to prevent the oxide from vaporizing during the sintering step.

[0072] The oxide sintered body manufactured through the above-mentioned process has a relative density of 98% or more and 1x10 -3 1x10 -4 It can have resistivity characteristics of Ωcm, and specifically, a relative density of 98.0 to 99.9% and a specific gravity of 3.0 × 10 -3 4.99 × 10 -3 It can have a resistivity characteristic of Ωcm.

[0073] (iv) Sputtering target manufacturing

[0074] Next, the sintered body is removed and processed. For example, after removing the sintered body, the surface of the target can be polished by processing the upper and lower parts of the target by at least 1 mm.

[0075] Afterwards, a commercial sputtering target is manufactured through diffusion bonding and final processing commonly known in the industry.

[0076] Specifically, the oxide sintered body obtained in step S30 is bonded to a backing plate. Indium may be used as an adhesive, and a bonding rate of 95% or higher is preferably achieved. Subsequently, machining is performed using machining equipment to reach the final target thickness, and the backing plate surface is subjected to bead and / or arc spray treatment to obtain the final sputtering target.

[0077]

[0078] <Oxide thin film>

[0079] Another example of the present invention is a metal oxide thin film deposited using the aforementioned IGZO dendritic oxide semiconductor sputtering target. Such a metal oxide thin film can be formed by performing sputtering using the aforementioned sintered body as a target material.

[0080] Although the above oxide thin film may exhibit slight differences in composition depending on the deposition atmosphere, it is manufactured by sputtering the aforementioned oxide target and thus has substantially the same composition as the target. Accordingly, an oxide thin film having excellent relative density, electrical conductivity and resistance characteristics, and low reflection characteristics can be formed.

[0081] For example, the average grain size of the crystal phase included in the oxide thin film may be 5 to 30 μm, and the thickness of the oxide thin film may be 5 to 50 nm. However, the present invention is not particularly limited thereto.

[0082] As another specific example, the oxide thin film may have an average reflectivity of 25% or less at a wavelength of 360 to 740 nm, and a sheet resistance of 300 to 1,300 Ω / sq at a thickness of 100 to 500 Å.

[0083] This thin film evaluation is not particularly limited and can be appropriately performed under common conditions known in the art. For example, a bonded target is deposited with a thin film using DC sputtering, and the thin film deposition conditions are a power density of 0.5 to 1.5 w / cm. 2 , Ar Gas atmosphere, and substrate temperature are evaluated at room temperature. In order to observe the roughness of the target surface according to the amount of target used (consumption), the roughness of the target surface, specifically the roughness of the consumption surface, is measured using a roughness meter when 50 wt% of the total 100 wt% of the target is consumed or 30 vol% of the total 100 volume% is consumed. If the surface roughness of the consumed target is high at this time, it can be seen that a large number of nodules have been generated in the area where the plasma discharge occurs. If a large number of nodules are generated in this way, they fall as foreign substances in the glass, which causes an increase in the defect rate of the final product.

[0084] In view of the above, it can be confirmed that the present invention is an optimized composition capable of deriving a fine and uniform grain size of an IGZO-based sputtering target by controlling the surface roughness of a certain consumed target to a predetermined range compared to the average grain size of an unused target, and at the same time suppressing grain growth and surface roughness growth within a sintered body, thereby ensuring homogeneity and high quality of a thin film.

[0085] The metal oxide thin film according to the present invention can be formed (deposited) using a conventional sputtering method known in the art. One example of the manufacturing method includes a step of mounting the aforementioned IGZO-based sputtering target and then depositing the film at room temperature in an oxygen and / or argon atmosphere in a vacuum chamber. In this case, sputtering can be performed using DC sputtering.

[0086] The substrate and sputtering device used can be any of those known in the art without limitation. Specifically, the film can be formed by supplying oxygen or oxygen and high-purity argon gas at a rate of 80 to 110 sccm (standard cubic centimeters per minute) in a vacuum chamber, and specifically, by supplying at a rate of 95 to 105 sccm, and the film can be deposited at room temperature (RT) without applying temperature to the substrate on which the film is to be formed. In addition, the power density of the DC sputter is 200±30 W / cm 2 The thickness of the metal oxide thin film may be 5 to 50 nm, but is not particularly limited thereto.

[0087] The oxide thin film obtained as described above can be used in various ways in the manufacture of semiconductor devices, and for example, can be applied for forming wiring or electrodes in the manufacture of semiconductors. In particular, the metal oxide thin film can be used as at least one of a gate layer, a source layer, and a drain layer of a thin film transistor (TFT). When the thin film of the present invention is used as a barrier layer of the source and drain electrodes included in a thin film transistor, the contact resistance can be reduced, and the physical properties of the thin film transistor can be improved by having excellent transparency and a low refractive index.

[0088] The IGZO sputtering target according to the present invention described above and the oxide thin film formed therefrom can suppress the connection resistance with the TFT structure of LCD and OLED or the electron injection layer of an organic electroluminescent device to a low level. Accordingly, the oxide thin film described above can be applied without limitation to various display devices such as liquid crystal displays or organic electroluminescent displays; information transmission devices such as flat panel displays such as LCDs, PDPs, OLEDs, and LEDs; surface light source lighting devices such as OLEDs and LEDs; touch panels; mobile phones, tablets, and / or information transmission devices using the same.

[0089] Hereinafter, the present invention will be described in detail through examples. However, the following examples are only illustrative of the present invention, and the present invention is not limited to the following examples.

[0090]

[0091] [Example 1]

[0092] Al and Sn were used as metals (M), and each metal oxide powder was weighed so that the weight % (wt%) ratio of (In+Ga+Zn+M) / (In+Ga+Zn) was 1.0%, and then wet mixed with a bead mill. The mixture was spray-dried using a spray dryer, and the spheroidized powder obtained was used for molding. The molding process was performed by first performing uniaxial pressing molding, and secondly, a molded body was manufactured through an isotropic molding machine. The molded density of the final molded body was 60-65%. Sintering was performed using the molded body, and the sintering conditions were maintained at 1,430°C for 10 hours, and 40 L of oxygen was injected per minute as gas. The relative density of the oxide sintered body target of Example 1 manufactured as described above was 98.5%, and the target resistivity was 5.0×10 -3 It was measured in Ωcm. After surface processing the manufactured target, indium bonding was performed on a backing plate to secure a bonding rate of 95% or higher.

[0093] The bonded target was mounted on a DC Sputter, and thin film deposition was performed under a power of 200 W, Ar Gas of 100 sccm, working pressure of 1.2 Pa, and room temperature atmosphere. The thin film thickness was deposited as 500 Å, and the thin film composition was measured in atomic % using XPS to confirm the content ratio of InGaZn, which is the main composition of the target. The content was detected to be In:Ga:Zn = 1:1:1, which is the same as the element % of the target (see Table 1 below).

[0094] In addition, a thin film was deposited until 30 volume% of the initial weight of the target was consumed. After a certain amount of consumption, the surface roughness of the consumed surface of the target was measured using a roughness meter (Mitutoyo, SJ210). As a result, the target surface roughness was 12-14 ㎛, which was approximately 20% higher than the grain size of the oxide sintered target, and a trace amount of foreign matter in the plasma discharge region was normal (see Table 1 below).

[0095]

[0096] [Comparative Example 1]

[0097] An oxide sintered sputtering target of Comparative Example 1 was manufactured in the same manner as Example 1, except that Al and Sn were not used as metal (M) components.

[0098]

[0099] [Comparative Example 2]

[0100] An oxide sintered sputtering target of Comparative Example 2 was manufactured in the same manner as in Example 1, except that the weight % (wt%) ratio of (In+Ga+Zn+M) / (In+Ga+Zn) was changed to 5.0% instead of 1.0%.

[0101]

[0102] [Comparative Example 3]

[0103] An oxide sintered sputtering target of Comparative Example 3 was manufactured in the same manner as in Example 1, except that the weight % (wt%) ratio of (In+Ga+Zn+M) / (In+Ga+Zn) was changed to 10.0% instead of 1.0%.

[0104]

[0105] [Experimental Example 1] Evaluation of the physical properties of a sputtering target

[0106] The properties of each sputtering target manufactured in Example 1 and Comparative Examples 1 to 3 and the oxide thin films manufactured therefrom were measured as follows, and the results are shown in Table 1 below.

[0107] (1) Measurement of physical properties of sputtering targets

[0108] The relative density, resistivity, and grain size of each oxide sintered sputtering target were measured.

[0109] (2) Measurement of physical properties during sputtering consumption

[0110] Thin films were deposited on each sputtering target until 30% by volume of the initial weight of the target was consumed, and the surface roughness of the target's consumed surface was measured after a certain amount of consumption. In addition, the current generated in the sputtering target was measured when a DC power density of 200 W was applied.

[0111] Here, Fig. 1(a) is a photograph after the sputtering target of Example 1 was consumed by about 30% by volume, and Figs. 1(b) to 1(d) are photographs after the sputtering targets of Comparative Examples 1 to 3 were consumed under the same conditions.

[0112] (3) Measurement of physical properties of oxide thin films

[0113] After thin film deposition was performed on each sputtering target under predetermined conditions, the thin film composition was measured in atomic % using XPS to confirm the content ratio of InGaZn, which is the main composition of the target.

[0114] Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Metal (Al+Sn) (wt%) 1.00 5.0 10.0 Relative density (%) 99.0 98.5 99.2 99.3 Target resistivity (Ωcm) 4.5×10 -3 5.0×10 -3 5.5×10 -3 8.0×10 -3 Grain size (㎛) 13 ㎛ 10 ㎛ 30 ㎛ 200 ㎛ Applied current (200 W) 0.27 A 0.30 A 0.52 A 0.65 A Main component Thin film composition (In : Ga : Zn at%) 1 : 1 : 11 : 1 : 11 : 1 : 11.2 : 1 : 0.8 Surface roughness of the target after consumption (㎛) 10-12 ㎛ 12-14 ㎛ 40-55 ㎛ 235-260 ㎛ Sintering temperature (℃) 1,450 1,430 1,480 1,530

[0115] As shown in Table 1 above, in the case of Example 1 manufactured using 1.0 wt% of metal (M) dopant, it was found that the relative density of the oxide sintered body equivalent to those of Comparative Examples 2 and 3 was secured, and the resistivity characteristics were better than those of Comparative Examples 1 to 3. In addition, it was found that the average grain size present in the sintered body had a finer and more uniform grain size than that of Comparative Example 1 which did not contain the metal dopant. In addition, as a result of checking the surface roughness when the sputtering target was consumed, in the case of Comparative Example 2 using 5 wt% of metal dopant, the grain size of the sintered body within the target was 30 ㎛, whereas the surface roughness of the consumed surface was 40-55 ㎛, which was an increase of 133 to 183%. In contrast, in the case of Example 1 using 1.0 wt% of metal dopant, it was found that the fine surface roughness was reduced compared to the grain size of the sintered body. And it was found that the applied current generated at the target also had a lower applied current than Comparative Examples 1 to 3.

[0116] In addition, as a result of measuring the composition of the oxide thin film in atomic % through XPS, it was confirmed that the main composition of In:Ga:Zn was maintained in the case of Example 1.

[0117]

[0118] [Experimental Example 2] Composition Evaluation

[0119] The main composition of each sputtering target manufactured in Example 1 and Comparative Examples 1 to 3 was confirmed as follows, and the results are shown in Table 2 below.

[0120] Composition (wt%)Example 1Comparative Example 1Comparative Example 2Comparative Example 3In45.4845.9443.6441.35Ga27.6227.9026.5125.11Zn25.9026.1624.8523.54Metal (Al+Sn)1.0-5.010.0Total metal in sintered body (wt%)100100100100

Claims

1. A sputtering target comprising a sintered body of an oxide containing indium (In), gallium (Ga), zinc (Zn), and metal (M), The above metal (M) includes at least one selected from the group consisting of Al, Sn, Hf, Ti, and Zr, The content of the above metal (M) is less than 5 wt% based on 100 wt% of the total metal excluding oxygen, A sputtering target, wherein the surface roughness of the consumed surface of the target is 1.2 times or less compared to the crystal grain size of the target, based on a sputtering target that has been consumed by 30 volume%.

2. In paragraph 1, A sputtering target, wherein the above metal is contained in an amount of 3 wt% or less relative to 100 wt% of the total metal excluding oxygen.

3. In paragraph 1, A sputtering target having an average grain size of 1 to 25 ㎛ contained in the above sintered body.

4. In paragraph 1, A sputtering target having a surface roughness of a consumed surface of the target of 30 ㎛ or less, based on a target consumed by 30 volume%.

5. In paragraph 1, The resistivity is 3.0 × 10 -3 4.99 × 10 -3 Ωcm, A sputtering target having a relative density of 98.0 to 99.9%.

6. In paragraph 1, When deposited under an inert atmosphere with 200 W of DC power, the current generated in the sputtering target was 0.30 A / cm. 2 Sputtering target less than .

7. In paragraph 1, The above sputtering target is a sputtering target that does not generate cracks when deposited by applying 200 W of DC power in an inert atmosphere.

8. An oxide thin film formed from a sputtering target described in any one of claims 1 to 7.

9. In paragraph 8, An oxide thin film in which the atomic % ratio of indium (In): gallium (Ga): zinc (Zn) in the above oxide thin film is in the range of 1:1:

1.

10. In paragraph 8, An oxide thin film, wherein the average grain size of the crystal phase contained in the oxide thin film is 5 to 30 ㎛.

11. In paragraph 8, An oxide thin film having a thickness of 5 to 50 nm.

12. In paragraph 8, The above oxide film is, The average reflectance at a wavelength of 360 to 740 nm is less than 25%, An oxide thin film having a sheet resistance of 300 to 1,300 Ω / sq at a thickness of 100 to 500 Å.

13. A thin film transistor comprising the oxide thin film described in claim 8.

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