KR20100052714A - High density zinc oxide based sputtering target - Google Patents

Abstract

PURPOSE: A high-density zinc oxide sputtering target is provided to improve weather and corrosion resistances by adding trivalent fluoride. CONSTITUTION: A high-density zinc oxide sputtering target comprises a first oxide of 001~05 weight%, a second oxide of 05~10 weight%, and the rest zinc oxide. The first oxide whose metallic ion is bivalent includes CaO, SrO, and BaO. The second oxide whose metallic ion is trivalent includes Al_2O_3, Ga_2O_3, and In_2O_3. The number of kinds of second oxide is two or more.

Description

High density zinc oxide based sputtering target

The present invention relates to a high-density zinc oxide-based sputtering target material used for forming a transparent conductive film having a low resistance characteristic by a sputtering method, and more specifically, zinc oxide as a main component and a metal ion of an additive O oxide having a high density as oxidation, characterized in that the density produced by an oxide and a fluoride with a trivalent atom is added to the same time variance of 5.6 ~ 5.74 g / cm ³ relates to a sputtering target associated material.

       The transparent conductive film is an essential material for securing conductivity and transparency by coating a panel used in a liquid crystal display (LCD), a plasma display panel (PDP), an organic light emitting device, and a solar cell. The method of forming this transparent conductive film is usually performed by means which are generally referred to as physical vapor deposition, such as vacuum deposition or sputtering. In particular, a large-area uniform thin film can be mass-produced in most cases by the direct current magnetron sputtering method because of its operability and film stability.

A transparent conductive film used for an information display device such as a liquid crystal display (LCD), a PDP, etc. is mainly formed by molding a mixed powder of indium tin oxide (hereinafter referred to as ITO) and processing a sintered body sintered at a temperature of 1500 ° C. or higher. Target materials are used representatively.

In recent years, the liquid crystal display (LCD) and plasma display panel (PDP) markets have expanded rapidly, and the flat panel display (FPD) market is rapidly expanding, and a transparent conductive film that is transparent to visible light and conductive is essential. Representative material is ITO and has been used as a representative material of a transparent conductive film for a long time. However, there has been a resource problem with indium metal, which is a raw material of ITO, as a rare metal, and as demand increases, it is expected to deplete the indium resources in excess of the mineable reserves in 2018. It is emerging. Against this background, the need for low resistance and high functional transparent conductive materials that can replace ITO is rapidly increasing. The sputtering method is applied to the formation method of an ITO thin film, since the FPD manufacturing line requires uniform film formation of a large area. For this reason, the film formation method of an ITO substitute material should also be a material suitable for sputtering method, and it should be available only by replacing a target.

As a substitute material for indium of the transparent conductive ITO target material, zinc oxide is a target material mainly composed of zinc oxide, and has been continuously researched and developed since the late 1980s due to the ease of supply and availability of rich zinc resources. .

As such a zinc oxide-based target material, in order to add conductivity, one or more kinds of oxides of an element having a trivalent valence are added, and a method of producing a sputtering target material sintered at 1300 ° C. or higher at an addition amount of 0.5-20% or more. Have been studied. In addition, a method of forming and adding a spinel phase by complexing a metal oxide having a trivalent or higher valence with zinc oxide in advance has been patented in Japan, and has a central particle diameter of a sintered body and a powder having improved crystal orientation and improved electrical conductivity. The sputtering characteristics of the target material and the thin film produced by simultaneously adding oxides, nitrides and composite oxides having valences of three or more to the aluminum oxide addition composition known to have excellent conductivity Advancing in technology to increase the characteristics.

Target materials represented by these techniques may be represented by aluminum zinc oxide (hereinafter referred to as AZO, or ZAO), gallium zinc oxide (GZO), tin zinc oxide (TZO), silicon zinc oxide (SZO), zinc zinc oxide (BZO), and the like. In addition, elements, such as Al, Ga, In, Ge, Si, Sn, Ti, are typical as an element added simultaneously. However, unlike ITO, when the thin film is manufactured by the sputtering method using a zinc oxide-based target, the thin film obtained is a characteristic of the transparent conductive film when it is contacted with an alkaline peeling liquid used in a high humidity and temperature environment or during a liquid crystal display (LCD) process. Due to the disadvantage of high resistance and peeling or being easily destroyed by chemicals penetrated into the microstructure of the thin film, the function may be impaired. In the LCD manufacturing environment in which a multilayer thin film is formed and patterned like a liquid crystal display device, the device is formed through patterning. It has a disadvantage of poor durability of the thin film. In addition, in the case of the sintered body in which the trivalent or higher element added to add conductivity to the zinc oxide is added at a temperature of 1300 ° C. or less, densification is not performed completely, resulting in a decrease in sintering density and sintering at a temperature of 1300 ° C. or more. After solid solution is dissolved within the solid solution limit by reaction with zinc oxide, it precipitates as a crystalline phase containing excess additive element known as secondary phase, and zinc oxide lacking additive element is volatilized to regenerate pores in the sintered compact, resulting in a sintered density of 5.6. Due to the problem that the density decreases to a limit value of g / cm ³ , the produced sintered body is processed into a sputtering target material to discharge the target during deposition of the thin film by sputtering due to the influence of trace gas remaining in the pores during manufacturing the thin film. There are problems of poor stability and increased resistance.

In the present invention, the zinc oxide-based sputtering target material used to form the transparent conductive film by the sputtering method in order to solve the problems of the prior art as described above, an oxide having a trivalent valence of a conductive additive function added for low resistance and At the same time, a high density target material can be prepared by introducing an oxide having a bivalent valence that suppresses the precipitation of the secondary phase produced by the reaction between the trivalent element and zinc oxide, and additionally forms a trivalent fluoride containing the fluorine element. A high density zinc oxide based target material was developed to provide a thin film having excellent environmental resistance and corrosion resistance by using a target prepared by simultaneous addition.

In order to achieve the above object, the present invention adds 0.01 to 0.5% of one of the oxides specified as CaO, SrO, and BaO, in which the metal ion has a divalent valence, and the Al ₂ O having a trivalent valence. ₃ , Ga ₂ O ₃ , In ₂ O ₃ specified in the amount of two or more of the added amount of the oxide is co-dispersed at a weight ratio of 0.5 to 10%, the remainder is zinc oxide, the density is 5.6 ~ 5.74g / cm ³ The present invention relates to a zinc oxide-based sintered body having a specific resistance of 1 × 10 ⁻³ Ωcm or less. Specifically, the present invention relates to a zinc oxide-based sintered compact, which is prepared by adding an oxide added to the sintered compact in the same weight ratio in the form of fluoride. In addition, the average particle size of the mixed powder of the zinc oxide powder and the additive is 0.2 ~ 3㎛, the average granule size of the dry granulated powder after mixing is 40 ~ 100㎛ 1450 after the press molding the molded article formed under cold constant pressure The air filtered at the temperature of ~ 1550 ℃ is introduced at a flow rate of 5 ~ 50L per minute to maintain a uniform temperature distribution and atmosphere of 20% oxygen concentration in the atmosphere even at high temperature, and to sinter by maintaining at less than 2 hours at the sintering temperature And a sputtering target material, wherein the sintered body is subjected to a planar polishing process, cut, and then ultrasonically cleaned, dried at a temperature of 100 ° C., and attached to a cooling plate made of copper or titanium with an indium as an adhesive. It is about. In addition, the sputtering target material, characterized in that used to form a transparent conductive thin film excellent in low resistance characteristics, moisture resistance and chemical resistance by mounting the target prepared in the direct current magnetron sputtering apparatus.

According to the present invention, in the zinc oxide-based sputtering target material used for forming the transparent conductive film by the sputtering method, an oxide having a trivalent valence of a trivalent valence of conductive addition function added for low resistance, and a trivalent element and zinc oxide, A high density target material can be prepared by introducing an oxide having a bivalent valence that suppresses the precipitation of a secondary phase generated by the reaction of a compound, or by additionally introducing a fluoride of a trivalent element. When manufacturing the transparent conductive film by the DC magnetron sputtering method utilized, it is possible to provide stable thin film properties excellent in discharge resistance of the target, low resistance properties, environmental resistance and corrosion resistance of the thin film.

Hereinafter, the present invention will be described in more detail. Addition elements for reducing the resistance of the ZnO-based transparent conductive material have been reported, such as Al, B, Ga, In, Ge, Si, Sn, Ti. In particular, many studies have been made in the case of a material to which elements of Al and Ga are added. Such conductivity-enhancing additive elements have a solid solution limit in the crystal structure of zinc oxide, so that even if the amount of addition is increased, they are not introduced into the crystal structure and the additional elements are precipitated in a secondary phase with zinc oxide having an excessive structure. The precipitated secondary phase is present in a spinel structure in the form of ZnAl ₂ O ₄ , ZnGa ₂ O _4, etc., so that the additive element is present in the grain boundary or grains between the zinc oxide system and the crystal grains of the solid solution so as to reduce the electrical conductivity of the sintered body. Becomes In addition, even if the addition element within the limit of the solid solution rate, there was a problem that the secondary phase is precipitated according to the sintering temperature and sintering conditions. The problem of precipitation of the secondary phase may occur during the manufacture of the sintered compact, and as a result, the discharge stability by plasma is poor when used as a sputtering target for obtaining a transparent conductive thin film under vacuum in a state of densification and uniform composition. Zinc oxide-based transparent conductive sputtering may cause problems such as arcing or nodule originating from regions where microstructures with excessively formed second phases are accumulated, which may reduce service life and increase foreign matter on the surface of the thin film on which the transparent conductive film is formed. It acts as an important factor to lower the characteristics of the target material. Secondary phase formation with zinc oxide in the form of granules of conductive additive elements consists of a composition similar to that of the secondary phase or the crystal structure around the microstructure in which the secondary phase is present, or as a zinc oxide with no additional element introduced. Due to the problem of nonuniformity, the zinc oxide is promoted to be volatilized at a high temperature, which may cause a decrease in pore density. Therefore, suppressing the precipitation of the secondary phase due to the introduction of conductive additive elements, and increasing the amount of the additive elements to increase the conductivity of the sintered body, increases the discharge stability during film formation and produces a zinc oxide-based transparent conductive target material that can be used stably. In order to be essential. In the present invention, in order to control the problem of the generation of the secondary phase by the conductive additive element, as a result of approaching and developing various areas such as controlling the sintering temperature condition, improving the uniform dispersibility with the additive element, the added metal ion is 2 Add one kind of oxides designated as CaO, SrO, and BaO having a valence of 0.01 to 0.5%, and specify metal ions as Al ₂ O ₃ , Ga ₂ O ₃ , or In ₂ O ₃ having a trivalent valence. It was invented that the production of high density zinc oxide-based sintered compacts was excellent because the effect of suppressing secondary phase formation was excellent when manufacturing a sintered compact in which two or more kinds of oxides were simultaneously introduced in a weight ratio of 0.5 to 10%. In addition, Ba among the elements having a valence of divalent has a role of stably solidifying in ZnO to solve the instability of the lattice formed through the substitution of Zn in the crystal structure of the trivalent element, which is a conductive addition element, to suppress the formation of the secondary phase. Invented very good. In addition, when the zinc oxide-based sintered body is manufactured by simultaneous addition of divalent and trivalent, the secondary phase inhibiting effect is excellent at high temperature, so that the sintered body of zinc oxide containing trivalent conductive element can be densified, and ultimately the lattice lacking additional elements. A zinc oxide-based sputtering target having a controllable volatilization of zinc oxide in the inside and having a uniform composition can be produced. In addition, when Sr and Ca are added simultaneously with the trivalent element, the same effect by the addition of Ba and the driving force in the low temperature region required for ZnO grain growth are increased to induce a higher density of the additive composition of trivalent elements such as Al and Ga. The effect is excellent. In the case of a deposited thin film made of a high density zinc oxide-based sintered body by simultaneously adding a divalent element and a trivalent or higher conductive additive element as a stuttering target, defects in the fine grain boundaries of the thin film grown on the c-axis To increase the film density and increase the heat resistance and humidity resistance in high humidity and high temperature environments, and additionally produce a sintered body in the form of a fluoride containing fluorine element in a trivalent element. The thin film obtained when used shows excellent corrosion resistance even when contacted with an alkaline liquid.

As described above, when divalent elements such as Ca, Sr, and Ba are introduced, they can be introduced in the form of oxides, and when trivalent elements are introduced in the form of oxides and fluorides. In addition, a method for mixing and dispersing the added element and zinc oxide is generally used as a bead mill using beads of zirconia, which is dispersed in deionized water or methyl in the case of an element capable of reacting with water. , Ethyl, isopropyl alcohol, etc. can be used as a dispersion solvent. Conditions for dispersion vary depending on the element and the type introduced, and uniform dispersion was obtained by adjusting the concentration, viscosity and temperature of the mixed powder slurry. The slurry mixed with the prepared zinc oxide and the compound of the additive element is made into a powder granulated by spray drying, filled into a mold and shaped, and then filtered air at a temperature of 1450-1550 ° C. at a flow rate of 5-50 L / min. The mixture was sintered by maintaining a 20% oxygen concentration in the atmosphere even at a high temperature and a uniform temperature distribution, and maintained at a sintering temperature for 1 hour or less. The prepared sintered body was plane polished and cut into a high-density sintered body having a density of 5.6 to 5.54 g / cm ³ , and then ultrasonically cleaned, dried at a temperature of 100 ° C., and attached to a cold plate made of copper or titanium as an adhesive. After it was mounted on a direct current magnetron sputtering device to form a uniform transparent conductive thin film was confirmed excellent thin film application characteristics of the sputtering target material prepared.

Hereinafter, the embodiment of the present invention will be described in more detail. However, the following examples are illustrative of the present invention, and the content of the present invention is not limited by the examples.

Example 1

     Zinc oxide powder having an average particle size of 1.0 μm, calcium oxide powder of 1.0 μm, aluminum oxide powder of 0.1 μm, and gallium oxide powder of 1.5 μm were weighed in the ratio shown in Table 1 by weight, and then mixed. The 55% phosphorus wet mixed slurry was dispersed into 0.1 mm zirconia beads in bead mill media. After spray drying the dispersed slurry, the center particle diameter of the granulated powder was measured to be 40 탆, and the obtained granulated powder was press-molded and sintered at 1550 ° C. for 3 hours while introducing air at a flow rate of 25 L / min. The sintered density of the zinc oxide-based target thus obtained was 5.69 g / cm 3.

     The obtained sintered compact was analyzed with an X-ray diffraction analyzer and a microstructure, and the high density sintered compact in which a secondary phase does not exist was confirmed. The resistivity of the sintered body was measured to obtain the results as shown in Table 1, and the conductive properties that could be formed with a direct current magnetron were confirmed. Cut and sinter the sintered body into 210X200, clean it, dry it, dry it, and attach it in 4 divisions as shown in Fig. 1 with indium as an adhesive on a copper cooling plate, and make it as a sputtering target material made of 420x400. After mounting, a transparent conductive thin film having a thickness of 1500 Pa was produced at a substrate temperature of 150 ° C. under an argon flow rate of 100 sccm under high vacuum, and the cross section of the thin film was observed with a high magnification electron scanning microscope as shown in FIG. 4. The sheet resistance of the fabricated thin film was measured and maintained for 24 hours in a constant temperature and humidity atmosphere at a temperature of 60 ° C. and 80% humidity. Further, the sheet resistance of the changed thin film was measured by immersing in a KOH 1.0% stripping solution at room temperature for 1 hour and then washing and drying. As a result of fabricating and evaluating the thin film, as shown in Table 1, the thin film characteristic showed excellent resistance characteristics, environmental resistance, and corrosion resistance.

[Example 2]

Zinc oxide powder having an average particle size of 1.0 μm, barium oxide powder of 0.5 μm, aluminum oxide powder of 0.1 μm, and gallium oxide powder of 1.5 μm were weighed in the ratio shown in Table 1 by weight, and then mixed. A slurry mixed with 55% ethyl alcohol was dispersed, spray-dried, press-molded and sintered as in Example 1. The sintered density of the zinc oxide-based target thus obtained was 5.74 g / cm 3. The obtained sintered body was analyzed by X-ray diffractometer as shown in FIG. 2 to analyze the crystal structure which does not exist in the secondary phase, and the specific resistance was measured in the same manner as in Example 1, processed into a target material, mounted on a direct current magnetron device, and the transparent conductive thin film was As a result of evaluating the sheet resistance and environmental resistance and chemical resistance at high temperature and high humidity of the fabricated and manufactured thin film, it showed excellent thin film characteristics as shown in Table 1 and excellent in environmental and corrosion resistance.

[ Example  3]

      Zinc oxide powder having an average particle size of 1.0 μm, strontium oxide powder of 1.5 μm, aluminum oxide powder of 0.1 μm, and gallium oxide powder of 1.5 μm were weighed in the proportions shown in Table 1 by weight, and then mixed. 55% phosphorus mixed slurry was dispersed, spray dried, pressure molded, and sintered as in Example 1. The sintered density of the zinc oxide-based target thus obtained was 5.71 g / cm 3. The resultant sintered body was analyzed for the presence of a secondary phase and the specific resistance as in Example 1, processed into a target material, mounted on a direct current magnetron device to fabricate a transparent conductive thin film, and evaluated the sheet resistance and environmental resistance and chemical resistance under high temperature and high humidity. As a result, as shown in Table 1, it showed excellent thin film properties with excellent resistance characteristics, environmental resistance and corrosion resistance.

Example 4

Zinc oxide powder having an average particle size of 1.0 μm, calcium oxide powder of 1.0 μm, aluminum oxide powder of 0.1 μm, gallium oxide powder of 1.5 μm, and indium oxide powder of 1.5 μm in weight ratios as shown in Table 1 After weighing, the mixture was mixed into a wet mixed slurry having a concentration of 55%, dispersed and spray dried as in Example 1, and pressed and sintered. The sintered density of the zinc oxide-based target thus obtained was 5.71 g / cm 3. The resultant sintered body was analyzed for the presence of a secondary phase and the specific resistance as in Example 1, processed into a target material, mounted on a direct current magnetron device to fabricate a transparent conductive thin film, and evaluated the sheet resistance and environmental resistance and chemical resistance under high temperature and high humidity. As a result, as shown in Table 1, it showed excellent thin film properties with excellent resistance characteristics, environmental resistance and corrosion resistance.

Example 5

Zinc oxide powder having an average particle size of 1.0 μm, barium oxide powder of 0.5 μm, aluminum oxide powder of 0.1 μm, gallium oxide powder of 1.5 μm, and indium oxide powder of 1.5 μm in weight ratios as shown in Table 1 After weighing, the mixture was mixed with 55% ethyl alcohol and dispersed in a slurry as in Example 1, spray-dried, and pressure molded to sinter. The sintered density of the zinc oxide-based target thus obtained was 5.69 g / cm 3. The resultant sintered body was analyzed for the presence of a secondary phase and the specific resistance as in Example 1, processed into a target material, mounted on a DC magnetron device to fabricate a transparent conductive thin film, and evaluated the sheet resistance and environmental resistance and chemical resistance under high temperature and high humidity. As a result, as shown in Table 1, it showed excellent thin film properties with excellent resistance characteristics, environmental resistance and corrosion resistance.

Example 6

Zinc oxide powder having an average particle size of 1.0 μm, strontium oxide powder of 0.5 μm, aluminum fluoride powder of 2.0 μm, gallium oxide powder of 1.5 μm, and indium oxide powder of 1.5 μm in weight ratios as shown in Table 1 After weighing, the mixture was dispersed, spray-dried, pressure-molded, and sintered as a wet mixed slurry having a concentration of 55% as in Example 1. The sintered density of the zinc oxide-based target thus obtained was 5.71 g / cm 3. The obtained sintered body was analyzed with the presence of a secondary phase and the specific resistance as in Example 1, processed into a target material, mounted on a direct current magnetron device to produce a transparent conductive thin film, and the sheet resistance of the manufactured thin film and the environmental resistance and chemical resistance under high temperature and high humidity were evaluated. As a result, as shown in Table 1, it showed excellent thin film properties with excellent resistance characteristics, environmental resistance and corrosion resistance.

[ Example  7]

     Zinc oxide powder having an average particle size of 1.0 μm, calcium oxide powder of 1.0 μm, aluminum oxide powder of 0.1 μm, gallium fluoride powder of 2.5 μm, and indium oxide powder of 1.5 μm in weight ratios as shown in Table 1 After weighing, the mixture was dispersed, spray-dried, pressure-molded, and sintered as a wet mixed slurry having a concentration of 55% as in Example 1. The zinc oxide-based target thus obtained had a sintered density of 5.67 g / cm 3. The resultant sintered body was analyzed for the presence of a secondary phase and the specific resistance as in Example 1, processed into a target material, mounted on a direct current magnetron device to fabricate a transparent conductive thin film, and evaluated the sheet resistance and environmental resistance and chemical resistance under high temperature and high humidity. As a result, as shown in Table 1, it showed excellent thin film properties with excellent resistance characteristics, environmental resistance and corrosion resistance.

Example 8

      Zinc oxide powder having an average particle size of 1.0 μm, barium oxide powder of 0.5 μm, aluminum oxide powder of 0.1 μm, gallium oxide powder of 1.5 μm, and indium fluoride powder of 3.0 μm in weight ratios as shown in Table 1 After weighing, the mixture was mixed with 55% ethyl alcohol and dispersed in a slurry as in Example 1, spray-dried, and pressure molded to sinter. The sintered density of the zinc oxide target thus obtained was 5.66 g / cm 3. The resultant sintered body was analyzed for the presence of a secondary phase and the specific resistance as in Example 1, processed into a target material, mounted on a direct current magnetron device to fabricate a transparent conductive thin film, and evaluated the sheet resistance and environmental resistance and chemical resistance under high temperature and high humidity. As a result, as shown in Table 1, it showed excellent thin film properties with excellent resistance characteristics, environmental resistance and corrosion resistance.

Comparative Example 1

      Zinc oxide powder having an average particle size of 1.0 μm and aluminum oxide powder of 0.1 μm were weighed in the ratio as shown in Table 1 by weight, and then mixed and dispersed as a wet mixed slurry having a concentration of 55% as in Example 1. And spray dried, pressure molded and sintered. The sintered density of the zinc oxide-based target thus obtained was 5.57 g / cm 3. The resultant sintered body was analyzed for the presence of a secondary phase and the specific resistance as in Example 1, processed into a target material, mounted on a direct current magnetron device to fabricate a transparent conductive thin film, and evaluated the sheet resistance and environmental resistance and chemical resistance under high temperature and high humidity. As a result, as shown in Table 1, the resistance was greatly increased, indicating the thin film characteristics of which the durability was lowered.

Comparative Example 2

      Zinc oxide powder having an average particle size of 1.0 μm and gallium oxide powder of 1.5 μm were weighed in the proportions as shown in Table 1 by weight, mixed, and dispersed in a wet mixed slurry having a concentration of 55% as in Example 1 And spray dried, pressure molded and sintered. The zinc oxide-based target thus obtained had a sintered density of 5.61 g / cm 3. The resultant sintered body was analyzed for the presence of a secondary phase and the specific resistance as in Example 1, processed into a target material, mounted on a direct current magnetron device to fabricate a transparent conductive thin film, and evaluated the sheet resistance and environmental resistance and chemical resistance under high temperature and high humidity. As a result, as shown in Table 1, the resistance was greatly increased to show the thin film characteristics of which the durability was lowered.

[ Comparative example  3]

      Wet mixed slurry having a concentration of 55% by weighing and mixing zinc oxide powder having an average particle size of 1.0 μm, aluminum oxide powder of 0.1 μm, and gallium oxide powder of 1.5 μm by weight in the same proportions as in Table 1 As in Example 1, the dispersion, spray drying, pressure molding and sintering. The sintered density of the zinc oxide-based target thus obtained was 5.57 g / cm 3. As a result of analyzing the presence of the secondary phase through the X-ray diffractometer, the obtained sintered body was confirmed that the secondary phase remained. As shown in Example 1, the specific resistance was analyzed and processed into a target material and mounted on a DC magnetron device. As a result of fabricating the transparent conductive thin film and evaluating the sheet resistance and environmental resistance and chemical resistance under high temperature and high humidity, as shown in Table 1, the resistance was greatly increased and the durability was reduced.

[ Comparative example  4]

      Wet mixed slurry having a concentration of 55% by weighing a zinc oxide powder having an average particle size of 1.0 μm, an aluminum oxide powder of 0.1 μm, and an indium oxide powder of 1.5 μm by weight in the same proportions as in Table 1, followed by mixing. As in Example 1, the dispersion, spray drying, pressure molding and sintering. The zinc oxide-based target thus obtained had a sintered density of 5.59 g / cm 3. The resultant sintered body was analyzed for the presence of a secondary phase and the specific resistance as in Example 1, processed into a target material, mounted on a direct current magnetron device to fabricate a transparent conductive thin film, and evaluated the sheet resistance and environmental resistance and chemical resistance under high temperature and high humidity. As a result, as shown in Table 1, the resistance was greatly increased, indicating the thin film characteristics of which the durability was lowered.

[ Comparative example  5]

       Zinc oxide powder having an average particle size of 1.0 μm, aluminum oxide powder of 0.1 μm, gallium oxide powder of 1.5 μm, and indium oxide powder of 1.5 μm were weighed in the proportions shown in Table 1 by weight, and then mixed. 55% phosphorus mixed slurry was dispersed, spray dried, pressure molded and sintered as in Example 1. The zinc oxide-based target thus obtained had a sintered density of 5.59 g / cm 3. The resultant sintered body was analyzed for the presence of a secondary phase and the specific resistance as in Example 1, processed into a target material, mounted on a direct current magnetron device to fabricate a transparent conductive thin film, and evaluated the sheet resistance and environmental resistance and chemical resistance under high temperature and high humidity. As a result, as shown in Table 1, the resistance was greatly increased to show the thin film characteristics of which the durability was lowered.

Hereinafter, Table 1 is an evaluation result of the said Example and a comparative example.

TABLE 1

1 is a view showing the appearance of a high density zinc oxide-based sputtering target having a sintered density of 5.69 g / cm ³ produced in Example 1 of the present invention.

FIG. 2 is a view showing a crystal structure in which a secondary phase in which a high density zinc oxide-based sputtering target having a sintered density of 5.74 g / cm ³ prepared in Example 2 of the present invention is analyzed by an X-ray diffraction analyzer does not exist.

FIG. 3 is a view showing a crystal structure in which a secondary phase of ZnGaO ₄ remains after analyzing a high-density zinc oxide-based sputtering target having a sintered density of 5.57 g / cm ³ produced by Comparative Example 3 of the present invention with an X-ray diffraction analyzer. .

4 is a high-density zinc oxide sputtering target having a sintered density of 5.69 g / cm ³ prepared in Example 1 of the present invention, mounted on a direct current magnetron sputtering apparatus, to prepare a thin film. It is a figure which observed the cross section.

Claims (5)

One of the oxides of which metal ions are designated CaO, SrO, or BaO having bivalent valences is added at a weight ratio of 0.01 to 0.5%, and the metal ions are Al ₂ O ₃ , Ga ₂ O ₃ , The resistivity characterized by the fact that two or more kinds of the oxides specified as In ₂ O ₃ are added and dispersed at a weight ratio of 0.5 to 10%, and the balance is made of zinc oxide to have a density of 5.6 to 5.54 g / cm ³ . Zinc oxide type sintered compact which is this 1x10 <^{-3> (} ohm) or less.       The method of claim 1,      The oxide added to the sintered compact is zinc oxide-based sintered compact, characterized in that the fluoride in the form of an added weight ratio. The average particle size of the mixed powder of zinc oxide powder and the additive was 0.2-3 μm, and the average granule size of the dry granulated powder after mixing was 40-100 μm. The air filtered at the temperature of ℃ is introduced at a flow rate of 5 ~ 50L per minute to maintain a uniform temperature distribution and atmosphere of 20% oxygen concentration in the atmosphere even at high temperature, and sintering by maintaining at less than 2 hours at the sintering temperature Sintered body. The sputtering target material of claim 3, wherein the sintered body according to claim 3 is subjected to planar polishing, cutting, and then ultrasonically cleaned, dried at a temperature of 100 ° C, and attached to a cooling plate made of copper or titanium with an indium as an adhesive. A sputtering target characterized in that the target prepared by the method of any one of claims 1 to 4 is mounted on a direct current magnetron sputtering apparatus to form a transparent conductive thin film having excellent low resistance, moisture resistance and chemical resistance. ashes.

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