KR20210044361A - Method of fabricating the metal oxide target and multi-dielectric layer manufactured thereby - Google Patents

Abstract

A method for manufacturing a metal oxide target comprises: a step of preparing mixed powder containing a first metal carbonated substance and a second metal carbonated substance; a step of reducing a particle size by ball-milling the mixed powder; a step of performing first heat treatment on the ball-milled mixed powder in an oxygen gas atmosphere to manufacture an intermediate oxide containing first metal and second metal; a step of manufacturing a preliminary target by forming the intermediate oxide; and a step of performing second heat treatment on the preliminary target in the oxygen gas atmosphere to manufacture a metal oxide target having a perovskite structure.

Description

Method of fabricating the metal oxide target and multi-dielectric layer manufactured by using the same

The present application relates to a method of manufacturing a metal oxide target, and a multi-dielectric thin film manufactured using the same, and more particularly, after ball milling a powder containing metal carbonate, it is removed at an oxygen concentration higher than the oxygen concentration in the atmosphere. A method of manufacturing a metal oxide target having a stoichiometric ratio of perovskite by sequentially performing 1 heat treatment and a second heat treatment, and a multi-dielectric thin film manufactured using the same.

In general, the metal oxide target is prepared by pre-sintering a metal precursor to prepare a pre-sintered body, and then performing main sintering. Through this sintering step, the density of the pre-sintered body can be increased, but at the same time, a metal oxide target that is contracted than the pre-sintered body can be manufactured. In addition, through a number of sintering processes, by-products may be generated, and accordingly, by-products may remain inside the finally manufactured metal oxide target.

Although a sintering aid may be added to lower the temperature or shorten the time of the sintering process, this may also remain inside the metal oxide target, thereby reducing the density of the manufactured metal oxide target.

Therefore, studies are being conducted to produce a metal oxide target having a high density by minimizing the addition of a sintering aid or the like. For example, in Korean Patent Publication 10-2011-0035239 (application number 10-2009-0092867), 10 to 35% by weight of ZnO, 5 to 20% by weight of SnO ₂ , the balance is characterized in that _{In 2} O ₃ high-density high-conductivity doped with ZnO, SnO ₂ firing a target composition in a furnace under an oxygen atmosphere for 5 hours to 1500 ~ 1640 ℃ and for producing a sintered compact by reducing treatment in a hydrogen atmosphere of _{600 ℃ in 2 O 3 -ZnO-} SnO _{2 A} target manufacturing method is disclosed.

One technical problem to be solved by the present application is to provide a method of manufacturing a high-density metal oxide target including strontium (Sr) and manganese (Mn), and a multi-dielectric thin film manufactured using the same.

Another technical problem to be solved by the present application is to provide a method of manufacturing a metal oxide target with improved oxidation degree by heat treatment in a peroxygen concentration atmosphere higher than the oxygen concentration in the atmosphere, and a multi-dielectric thin film manufactured using the same.

The technical problem to be solved by the present application is not limited to the above.

In order to solve the above technical problem, the present application provides a method of manufacturing a metal oxide target.

According to an embodiment, the method of manufacturing the metal oxide target includes: preparing a mixed powder including a first metal carbonate and a second metal carbonate, reducing a particle size by ball-milling the mixed powder, The ball-milled mixed powder is subjected to a first heat treatment in an oxygen gas atmosphere to prepare an intermediate oxide including a first metal and a second metal, forming a preliminary target by molding the intermediate oxide, and the preliminary target The second heat treatment in an oxygen gas atmosphere may include preparing a metal oxide target having a perovskite structure.

According to an embodiment, the second heat treatment of the preliminary target may include performing in an oxygen gas atmosphere having a concentration higher than the oxygen concentration in the atmosphere.

According to an embodiment, the second heat treatment of the preliminary target may include reacting the preliminary target and the oxygen gas to prepare the metal oxide target having an increased oxygen concentration than the preliminary target. have.

According to an embodiment, the second heat treatment of the preliminary target may include reacting the preliminary target and the oxygen gas to prepare the metal oxide target having a stoichiometric ratio of perovskite. I can.

According to an embodiment, the first heat treatment may be performed at a first temperature, and the second heat treatment may include a temperature higher than the first temperature.

According to an embodiment, the step of performing the first heat treatment may be performed for a first time, and the step of performing the second heat treatment may include being performed for a time longer than the first time.

According to an embodiment, the first heat treatment of the ball-milled mixed powder includes providing the ball-milled mixed powder to a crucible, a first side including a gas supply device, and a gas exhaust port spaced apart from the first side. Charging the crucible into a heat treatment apparatus including a tubular chamber including a second side surface, and a heating unit surrounding an outer circumferential surface of the tubular chamber, and raising the temperature of the heater unit, and supplying the gas into the tubular chamber. Providing oxygen gas through an apparatus to remove gaseous impurities generated by the reaction of the mixed powder and the oxygen gas through the gas exhaust port to prepare the intermediate oxide.

According to an embodiment, the impurities in a gaseous state may include those that are provided from the first side and move along the oxygen gas moving to the second side and do not remain in the intermediate oxide.

According to an embodiment, the first heat treatment of the ball-milled mixed powder may include removing a carbon element included in the ball-milled mixed powder by reaction with the oxygen gas, so that the intermediate oxide in which the carbon element does not remain. It may include the step of manufacturing.

According to an embodiment, the first metal may include strontium (Sr), and the second metal may include manganese (Mn).

In order to solve the above technical problem, the present application provides a method of manufacturing a multi-dielectric thin film.

According to an embodiment, the method of manufacturing the multi-dielectric thin film includes preparing the metal oxide target manufactured according to the method of manufacturing a metal oxide target according to the above-described embodiment in a chamber, and sputtering the metal oxide target. And epitaxially forming multiple dielectric thin films having multiple dielectric constants on the substrate.

A method of manufacturing a metal oxide target according to an embodiment of the present invention includes preparing a mixed powder including a first metal carbonate and a second metal carbonate, reducing a particle size by ball-milling the mixed powder, The ball-milled mixed powder is subjected to a first heat treatment in an oxygen gas atmosphere to prepare an intermediate oxide including a first metal and a second metal, forming a preliminary target by molding the intermediate oxide, and the preliminary target The second heat treatment in an oxygen gas atmosphere may include preparing a metal oxide target having a perovskite structure.

Ball milling the mixed powder may reduce the particle size of the mixed powder, thereby increasing the specific surface area of the mixed powder, and at the same time, making the particle distribution of the mixed powder uniform. Accordingly, reactivity may be increased in the first heat treatment step and the second heat treatment step, and the density of the metal oxide prepared through the first heat treatment step and the second heat treatment step may be improved. have.

The first heat treatment of the ball-milled mixed powder may include reacting a carbon element included in the ball-milled mixed powder with the oxygen gas to prepare the intermediate oxide from which the carbon element has been removed. That is, the intermediate oxide prepared as described above may not contain the carbon element or impurities formed by the reaction of the carbon element and the oxygen gas, and accordingly, the density of the intermediate oxide can be easily improved. .

After forming the intermediate oxide to prepare a preliminary target, the second heat treatment of the preliminary target may include heat treating the preliminary target under an oxygen concentration higher than the oxygen concentration in the atmosphere. The metal oxide target prepared accordingly may contain more oxygen elements than the preliminary target, and specifically, the metal oxide target may have a stoichiometric ratio of perovskite.

Accordingly, multiple dielectric thin films having multiple dielectric constants may be epitaxially formed on a substrate using the metal oxide target.

1 is a flowchart illustrating a method of manufacturing a metal oxide target according to an exemplary embodiment of the present invention.
2 to 4 are views for explaining a method of manufacturing a metal oxide target according to an embodiment of the present invention.
5 is a view showing a scanning electron microscope (SEM) image of mixed powder before and after a high-energy ball mill in a method of manufacturing a metal oxide target according to an embodiment of the present invention.
6 to 7 are diagrams showing BET analysis results of mixed powder before and after high-energy ball mill in the method of manufacturing a metal oxide target according to an exemplary embodiment of the present invention.
8 is a diagram illustrating an X-ray diffraction pattern (XRD) of an intermediate oxide manufactured through a first heat treatment step in a method of manufacturing a metal oxide target according to an exemplary embodiment of the present invention.
9 is a diagram illustrating an image photographed of a metal oxide target manufactured according to an embodiment of the present invention.
10 is a diagram illustrating an image of a metal oxide thin film manufactured using a metal oxide target according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the technical idea of the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed contents may be thorough and complete, and the spirit of the present invention may be sufficiently conveyed to those skilled in the art.

In the present specification, when a component is referred to as being on another component, it means that it may be formed directly on the other component or that a third component may be interposed therebetween. In addition, in the drawings, thicknesses of films and regions are exaggerated for effective description of technical content.

In addition, in various embodiments of the present specification, terms such as first, second, and third are used to describe various elements, but these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. Accordingly, what is referred to as a first component in one embodiment may be referred to as a second component in another embodiment. Each embodiment described and illustrated herein also includes its complementary embodiment. In addition, in the present specification,'and/or' is used to mean including at least one of the elements listed before and after.

In the specification, expressions in the singular include plural expressions unless the context clearly indicates otherwise. In addition, terms such as "comprise" or "have" are intended to designate the presence of features, numbers, steps, components, or a combination thereof described in the specification, and one or more other features, numbers, steps, or configurations. It is not to be understood as excluding the possibility of the presence or addition of elements or combinations thereof.

In addition, in the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted.

1 is a flowchart illustrating a method of manufacturing a metal oxide target according to an exemplary embodiment of the present invention, and FIGS. 2 to 4 are views illustrating a method of manufacturing a metal oxide target according to an exemplary embodiment of the present invention.

Referring to FIG. 1, a mixed powder 140 including a first metal carbonate and a second metal carbonate may be prepared (S110 ).

Specifically, for example, the first metal carbonate may be strontium carbonate (SrCO ₃ ), and the second metal carbonate may be manganese carbonate (MnCO ₃ ).

1 to 3, the mixed powder 140 may be ball-milled to reduce the particle size (S120).

According to an embodiment, the mixed powder 140 may be a high-energy ball mill, and accordingly, the particle size of the mixed powder 140 may be reduced from a micro size to a nano size.

For example, as shown in FIG. 2, the mixed powder 140 may be provided to the mechanical stirring device 110. The mechanical stirring device 110 may be connected to the high-energy ball mill device 130 through the pump 120, and accordingly, the mixed powder 140 stirred in the mechanical stirring device 110 is the high-energy It may be provided in the ball mill device 130. Specifically, for example, the high-energy ball mill device 130 may be rotated at 2,000 rpm or more.

In this case, the high-energy ball mill device 130 may be further provided with a ball 150 in addition to the mixed powder 140 provided by the mechanical stirring device 110, and accordingly, as shown in FIG. , The ball 150 and the mixed powder 140 collide with each other while rotating, so that the size of the mixed powder 140 may be easily reduced. Specifically, for example, the ball 150 may be at least one of a zirconia ball, an alumina ball, or a glass ball.

As shown in FIG. 2, the mixed powder 140 provided in the high-energy ball mill device 130 and pulverized may be provided to the mechanical stirring device 110 again. That is, the mixed powder 140 is alternately provided to the mechanical stirring device 110 and the high-energy ball mill device 130, and the particle size may be reduced.

As described above, the ball milled mixed powder 140 may have a smaller particle size than before the ball mill, and thus, a cross-sectional area of the particle surface may be increased. In addition, through a high-energy ball mill process including the mechanical stirring device 110 and the high-energy ball mill device 130, the ball-milled mixed powder 140 may have a uniform particle deviation than before the ball mill. Specifically, for example, the above-described ball mill process may be performed for 24 hours.

If, unlike the above, if the step of performing the first heat treatment described later without the step of ball milling the mixed powder 140, that is, immediately after preparing the mixed powder 140, the step of performing the first heat treatment described later When performed, the mixed powder 140 may have a larger particle size than the ball milled mixed powder 140. Therefore, the contact area between the mixed powder 140 and the oxygen gas may be reduced in the first heat treatment step described later, and thus, the reaction between the mixed powder 140 and the oxygen gas may not be easily performed. have.

However, as described above, when the mixed powder 140 is ball milled, the particle size of the mixed powder 140 can be easily reduced, and accordingly, the ball milled mixed powder 140 and the oxygen gas By increasing the contact area between the balls, the reactivity between the ball-milled mixed powder 140 and the oxygen gas may be improved.

1 and 4, an intermediate oxide including a first metal and a second metal may be manufactured by subjecting the ball-milled mixed powder to a first heat treatment in an oxygen gas atmosphere (S130).

According to an embodiment, the ball-milled mixed powder 140 may be provided to a heat treatment apparatus and may be subjected to a first heat treatment at a first temperature for a first time in an oxygen gas atmosphere. Accordingly, the ball-milled mixed powder 140 may be sintered to prepare an intermediate oxide including the first metal and the second metal. For example, the first temperature may be 800 to 1200°C, and the first time may be 10 hours.

Specifically, as shown in FIG. 4, the heat treatment apparatus includes a first side 300 including a gas supply device 310, and a gas exhaust port 410 spaced apart from the first side 300. A tubular chamber including a second side surface 400 and heating units 230a and 230b surrounding outer circumferential surfaces 200a and 200b of the tubular chamber may be included. Here, the ball-milled mixed powder 140 may be provided to the crucible 220, and the crucible 220 may be charged into the heat treatment apparatus. In this case, the bowled mixed powder 140 charged in the heat treatment apparatus may be provided at the location of the source 210.

After the ball-milled mixed powder 140 is charged into the tubular chamber of the heat treatment apparatus, the temperature of the heating units 230a and 230b may be increased, and at the same time, the gas supply device 310 in the tubular chamber Through the oxygen gas may be provided.

According to an embodiment, the oxygen gas may be provided in the tubular chamber at a higher concentration than the oxygen concentration in the atmosphere. Specifically, for example, the oxygen gas may be supplied into the tubular chamber at a flow rate of 3L/min.

As described above, the ball-milled mixed powder 140 may include the first metal carbonate and the second metal carbonate. That is, the ball-milled mixed powder 140 may include a carbon element included in the first metal carbonate and the second metal carbonate. Accordingly, the first heat treatment of the ball-milled mixed powder 140 includes forming a gaseous impurity by reacting the carbon element included in the ball-milled mixed powder 140 with the oxygen gas. can do. For example, the impurity may be carbon dioxide.

The gaseous impurities may be removed in the tubular chamber by using the oxygen gas transferred from the gas supply device 310 to the gas exhaust port 410 as a carrier gas.

Unlike the above, the oxygen gas may be provided in the tubular chamber at the same concentration as the oxygen concentration in the atmosphere. In this case, due to the lack of oxygen gas, carbon may remain in the intermediate oxide. In addition, most of the oxygen gas provided in the tubular chamber can be used in a process of forming the impurities in a gaseous state by reacting with the carbon element. Accordingly, the flow of the oxygen gas moving from the first side 300 to the second side 400 may not occur, and the impurities in the gaseous state generated as described above are not easily removed. , Carbon may remain in the intermediate oxide. Carbon remaining in the intermediate oxide may cause cracks in the metal oxide target described below, and it may not be easy to epitaxially grow a thin film on the substrate using a metal oxide target including carbon.

However, as described above, the oxygen gas may be provided in the tubular chamber at a higher concentration than the oxygen concentration in the atmosphere. In this case, some of the oxygen gas provided in the tubular chamber may be consumed by being used in the reaction with the carbon element, and the oxygen gas remaining in the tubular chamber not used for the above-described reaction is the A flow of the oxygen gas may be formed from the first side 300 to the second side 400 in the tubular chamber. That is, the impurities in a gaseous state can be easily removed in the tubular chamber along the flow of the oxygen gas, and accordingly, the intermediate oxide substantially not including the carbon can be prepared.

Referring to FIG. 1, a preliminary target may be manufactured by molding the intermediate oxide (S140).

According to an embodiment, after grinding the intermediate oxide, the preliminary target may be manufactured by providing it to a mold.

As described above, by the first heat treatment step, the ball-milled mixed powder 140 may be sintered to prepare the intermediate oxide. In this case, the intermediate oxide may have a reduced particle size uniformity compared to the ball-milled mixed powder 140.

Therefore, by pulverizing the intermediate oxide, the particle size of the intermediate oxide can be reduced, and at the same time, the uniformity of the particle size of the intermediate oxide can be increased. Accordingly, the density of the preliminary target manufactured by molding the pulverized intermediate oxide may be improved.

1 and 4, a metal oxide target having a perovskite structure may be manufactured by performing a second heat treatment on the preliminary target in an oxygen gas atmosphere (S150).

Specifically, the preliminary target may be subjected to the second heat treatment at a temperature higher than the first temperature for a time longer than the first time, thereby manufacturing the metal oxide target. For example, the step of performing the second heat treatment may be performed at a temperature of 1300° C. or higher for 24 hours.

According to an embodiment, the second heat treatment of the preliminary target may be performed using the same heat treatment apparatus as the first heat treatment of the ball-milled mixed powder 140. That is, as described above, the preliminary target may be provided at the location of the source 210 and subjected to a second heat treatment. In this case, the oxygen gas may be provided in the tubular chamber at a concentration higher than the oxygen concentration in the atmosphere. For example, the oxygen gas may be supplied into the tubular chamber at a flow rate of 3L/min.

4, the preliminary target provided in the crucible 220 may be combined with the oxygen gas provided in the tubular chamber through the gas supply device 310. Accordingly, the manufactured metal oxide target may have more oxygen elements than the preliminary target.

According to an embodiment, the metal oxide target may include the first metal, the second metal, and the oxygen element, and in this case, the metal oxide target may have a stoichiometric ratio of perovskite. have. That is, the metal oxide target may include the first metal, the second metal, and the oxygen element in a molar ratio of 1:1:3.

In addition, according to an embodiment, the flow rate of oxygen supplied in the first heat treatment and/or the second heat treatment process may be controlled according to the ball mill level (rpm or time) in the process of ball milling the mixed powder. Specifically, as the rpm and time for ball milling the mixed powder increase, the loss of oxygen in the mixed powder may increase, and accordingly, the oxygen flow rate supplied in the first heat treatment and/or the second heat treatment process increases. Can be. Accordingly, the metal oxide target of high density and high quality having a stoichiometric ratio of a perovskite structure can be manufactured.

As described above, after the metal oxide target ball-mills the mixed powder 140 including the first metal carbonate and the second metal carbonate, the first heat treatment is sequentially performed in an oxygen gas atmosphere in a heat treatment apparatus. And a second heat treatment step.

By the ball-milling step, the particle size of the mixed powder 140 may be reduced from a micro-size to a nano-size, and accordingly, the density of the metal oxide target may be improved.

The ball-milled mixed powder 140 may be subjected to a first heat treatment, so that the carbon element contained in the ball-milled mixed powder 140 may be removed by reaction with the oxygen gas. That is, the carbon element in the ball-milled mixed powder 140 is removed and sintered to prepare the intermediate oxide.

In other words, the intermediate oxide may include the first metal, the second metal, and an oxygen element. The intermediate oxide may be formed into a preliminary target, and the formed intermediate oxide may be manufactured by a second heat treatment process in an oxygen gas atmosphere to produce the metal oxide target in which the amount of the oxygen element is increased compared to the intermediate oxide. I can. That is, the metal oxide target having a stoichiometric ratio in which the first metal, the second metal, and the oxygen element has a perovskite structure may be manufactured through the second heat treatment process. In addition, as described above, the metal oxide target in which the density is improved and the occurrence of cracks is minimized may be provided.

Hereinafter, a method of manufacturing a metal oxide target according to a specific experimental example of the present invention and a characteristic evaluation result will be described.

Preparation of ball-milled mixed powder according to Experimental Example 1

A mixed powder was prepared by mixing strontium carbonate (SrCO ₃ ) and manganese carbonate (MnCO ₃ ) at a molar ratio of 1:1.

The mixed powder, zirconia balls, and ethanol were supplied to a high-energy ball mill device and ball milled at 2000 rpm for 24 hours to prepare a ball milled mixed powder according to Experimental Example 1.

As a comparative example of the ball milled mixed powder according to Experimental Example 1 described above, the mixed powder before the high-energy ball mill was defined as the ball milled mixed powder according to Comparative Example 1. Accordingly, the process conditions of the ball-milled mixed powder according to Experimental Example 1 and Comparative Example 1 were written in <Table 1> below.

High-energy ball mill process Comparative Example 1 X Experimental Example 1 O (2,000rpm)

Preparation of intermediate oxide according to Experimental Example 2

The ball-milled mixed powder according to Experimental Example 1 was dried at a temperature of 100° C. for 24 hours, and then provided to a crucible.

After loading the crucible into the heat treatment device, the temperature inside the heat treatment device was raised to 1000° C., and at the same time, oxygen gas was supplied into the heat treatment device at a flow rate of 3 L/min.

After the step of performing the first heat treatment for 10 hours, it was removed in the heat treatment apparatus to prepare an intermediate oxide according to Experimental Example 2.

Preparation of metal oxide target according to Experimental Example 3

After pulverizing the intermediate oxide according to Experimental Example 2, it was provided to a mold to prepare a 1 inch size preliminary target.

As in the method of manufacturing an intermediate oxide according to Experimental Example 2, the preliminary target was charged into the heat treatment apparatus.

The temperature inside the heat treatment device was raised to 1300°C, and at the same time, oxygen gas was provided in the heat treatment device at a flow rate of 3 L/min.

After the step of performing the second heat treatment for 24 hours, it was removed in the heat treatment apparatus to prepare a metal oxide target according to Experimental Example 3.

Preparation of metal oxide target according to Comparative Example 3

Manufacturing in the same manner as the metal oxide target according to Experimental Example 3, but in the step of performing the first heat treatment (preparation of the intermediate oxide according to Experimental Example 2), and in the step of performing the second heat treatment, instead of the oxygen gas atmosphere In turn, a metal oxide target according to Comparative Example 3 was prepared.

5 is a view showing a scanning electron microscope (SEM) image of mixed powder before and after a high-energy ball mill in a method of manufacturing a metal oxide target according to an embodiment of the present invention.

Referring to FIG. 5, surface images of the ball-milled mixed powder according to Experimental Example 1 and Comparative Example 1 of the present invention were measured. At this time, the average particle size of the ball-milled mixed powder according to Experimental Example 1 shown in FIG. 5(b) and the ball-milled mixed powder according to Comparative Example 1 shown in FIG. 5(a) was measured, and the following It was written in <Table 2> of.

Average particle size Comparative Example 1 (Fig. 5(a)) ~50μm Experimental Example 1 (Fig. 5(b)) ~50nm

As can be seen from <Table 2> and FIG. 5, _{the mixed powder including the strontium carbonate (SrCO 3} ) and the manganese carbonate (MnCO ₃ ) has a smaller average particle size after the ball mill than before the ball mill. I can. In addition, it was confirmed that the size variation between particles of the mixed powder was also reduced to 10% or less.

6 to 7 are views showing BET analysis results of mixed powders before and after a high-energy ball mill in a method of manufacturing a metal oxide target according to an exemplary embodiment of the present invention.

6 to 7, BET (Brunauer-Emett-Teller) is a numerical value representing the specific surface area of the object, and the distribution and size of the pores of the object are checked through adsorption and desorption of gas to the object. It can be expressed as the BET value. At this time, the BET values of the ball-milled mixed powder according to Comparative Example 1 (FIG. 6) and Experimental Example 1 (FIG. 7) of the present invention measured by the above analysis method were written in <Table 3> below.

BET specific surface area (m ² /g) Comparative Example 1 (Fig. 6) 1.1239 Experimental Example 1 (Fig. 7) 30.6634

As can be seen from <Table 3>, it can be seen that the specific surface area of the particles is increased by about 27 times in the mixed powder through the high-energy ball mill.

8 is a diagram illustrating an X-ray diffraction pattern (XRD) of an intermediate oxide manufactured through a first heat treatment step in a method of manufacturing a metal oxide target according to an exemplary embodiment of the present invention.

8, the crystal structure of the intermediate oxide according to Experimental Example 2 of the present invention was confirmed.

8, the intermediate oxides according to Experimental Example 2 are (012), (011), (013), (004), (022), (014), (023), (114), (015) ), (030), (123), (026), (022), and (102) planes were confirmed to have peaks. Accordingly, it can be seen that the intermediate oxide according to Experimental Example 2 is strontium manganite (SrMnOx).

9 is a diagram illustrating an image photographed of a metal oxide target manufactured according to an embodiment of the present invention.

Referring to FIG. 9, a metal oxide target according to Experimental Example 3 (FIG. 9(b)) and a metal oxide target according to Comparative Example 3 (FIG. 9(a)) were photographed.

As shown in (a) of FIG. 9, the metal oxide target according to Comparative Example 3 was manufactured in the same manner as the metal oxide target according to Experimental Example 3, but was manufactured in the atmosphere instead of a peroxygen atmosphere. Accordingly, it can be seen that cracks are generated in the manufactured metal oxide target during the cooling process after the second heat treatment step.

On the other hand, as shown in (b) of FIG. 9, it was confirmed that the metal oxide target according to Experimental Example 3 did not generate cracks in the cooling process after the second heat treatment step.

Accordingly, as described above with reference to FIGS. 1 to 4, when the metal oxide target is heat-treated in a peroxygen atmosphere, it can be seen that cracks on the surface and inside of the metal oxide target are minimized.

10 is a diagram illustrating an image of a metal oxide thin film manufactured using a metal oxide target according to an embodiment of the present invention.

Referring to FIG. 10, a metal oxide target according to Comparative Example 3 (FIG. 10(a)) and a metal oxide target according to Experimental Example 3 of the present invention (FIG. 10(b)) described above with reference to FIG. Each of the metal oxide thin films prepared by sputtering was photographed.

As shown in (a) of FIG. 10, the thin film prepared using the metal oxide target according to Comparative Example 3 generated powder, and it was confirmed that the thin film had opacity due to low uniformity.

On the other hand, as shown in (b) of FIG. 10, it was confirmed that the thin film manufactured using the metal oxide target according to Experimental Example 3 was relatively uniformly deposited.

As described above, the present invention has been described in detail using preferred embodiments, but the scope of the present invention is not limited to specific embodiments, and should be interpreted by the appended claims. In addition, those who have acquired ordinary knowledge in this technical field should understand that many modifications and variations are possible without departing from the scope of the present invention.

110: mechanical strring device
120: pump
130: high-energy ball mill device
140: powder
150: ball
200a, 200b: outer peripheral surface
210: source
220: crucible
230a, 230b: heating unit
300: first side
310: gas supply device
400: second aspect
410: gas exhaust port

Claims (11)

Preparing a mixed powder comprising a first metal carbonate and a second metal carbonate;
Ball-milling the mixed powder to reduce the particle size;
Preparing an intermediate oxide including a first metal and a second metal by subjecting the ball-milled mixed powder to a first heat treatment in an oxygen gas atmosphere;
Forming a preliminary target by molding the intermediate oxide; And
A method of manufacturing a metal oxide target comprising the step of producing a metal oxide target having a perovskite structure by performing a second heat treatment on the preliminary target in an oxygen gas atmosphere.
The method of claim 1,
The second heat treatment of the preliminary target comprises performing in an oxygen gas atmosphere having a concentration higher than the oxygen concentration in the atmosphere.
The method of claim 1,
The second heat treatment of the preliminary target comprises reacting the preliminary target and the oxygen gas to prepare the metal oxide target having an increased oxygen concentration than the preliminary target.
The method of claim 1,
The second heat treatment of the preliminary target comprises reacting the preliminary target and the oxygen gas to prepare the metal oxide target having a stoichiometric ratio of perovskite. .
The method of claim 1,
The step of performing the first heat treatment is performed at a first temperature,
The second heat treatment is performed at a temperature higher than the first temperature.
The method of claim 1,
The first heat treatment step is performed for a first time,
The second heat treatment is performed for a time longer than the first time.
The method of claim 1,
The first heat treatment of the ball-milled mixed powder,
Providing the ball-milled mixed powder to a crucible;
The crucible is charged into a heat treatment apparatus including a first side including a gas supply device and a tubular chamber comprising a second side spaced apart from the first side and including a gas exhaust port, and a heating unit surrounding the outer circumferential surface of the tubular chamber. The step of doing; And
The temperature of the heater unit is raised, oxygen gas is provided in the tubular chamber through the gas supply device to remove gaseous impurities generated by the reaction of the mixed powder and the oxygen gas through the gas exhaust port, and the A method of manufacturing a metal oxide target comprising the step of preparing an intermediate oxide.
The method of claim 7,
The method of manufacturing a metal oxide target comprising the impurities in a gaseous state being provided from the first side and moving along the oxygen gas moving to the second side and not remaining in the intermediate oxide.
The method of claim 1,
The first heat treatment of the ball-milled mixed powder includes removing a carbon element contained in the ball-milled mixed powder by reaction with the oxygen gas to prepare the intermediate oxide in which the carbon element is not left. Method for producing a metal oxide target.
The method of claim 1,
The first metal is strontium (Sr),
The second metal is a method of manufacturing a metal oxide target comprising manganese (Mn).
Preparing the metal oxide target manufactured according to the method of manufacturing a metal oxide target according to claim 1 in a chamber; And
And sputtering the metal oxide target to epitaxially form a multi-dielectric thin film having a multi-dielectric constant on a substrate.

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