WO2020250586A1

WO2020250586A1 - Sputtering target and sputtering target manufacturing method

Info

Publication number: WO2020250586A1
Application number: PCT/JP2020/017913
Authority: WO
Inventors: 優和田; 勝仁齋藤; 裕川越; 健太郎武末; 高橋　一寿
Original assignee: 株式会社アルバック
Priority date: 2019-06-10
Filing date: 2020-04-27
Publication date: 2020-12-17
Also published as: CN113508187A; TWI815011B; JP7016432B2; JPWO2020250586A1; KR102429251B1; KR20210118173A; CN113508187B; TW202102702A

Abstract

[Problem] To provide a sputtering target with which particles and abnormal discharge can be suppressed even if the sputtering target is long and cylindrical. [Solution] A sputtering target, wherein a target body comprises a plurality of target members that are arranged along the outer circumferential surface of a cylindrical backing tube, and that have a circular arc-shaped cross section. The plurality of target members are each disposed so as to be separated from each other around a central axis of the backing tube. A gap that is formed between the target members which are aligned around the central axis extends in the central axis direction of the backing tube. A bonding material is interposed between the backing tube and the target body so as to bond the backing tube and the plurality of target members to each other. A shielding member is provided between the bonding material and the target body so as to shield the gap from the bonding material side.

Description

Sputtering target and manufacturing method of sputtering target

The present invention relates to a sputtering target and a method for manufacturing the sputtering target.

With the increase in the screen size of flat-screen TVs, the size of the sputtering target used when manufacturing flat panel displays is increasing. Along with this, a large area oxide target has appeared. In particular, a film forming apparatus to which a long and cylindrical oxide target can be attached has been developed. A method of joining a plurality of cylindrical oxide sintered bodies to a cylindrical backing tube is provided in order to obtain a long cylindrical oxide target.

However, when a sputtering target is composed of a plurality of target members, adjacent target members may come into contact with each other due to thermal expansion of the target members, and the target members may crack. In order to prevent cracking due to this contact, a gap may be provided between adjacent target members (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2015-168832

However, particles are generated from the gaps, and abnormal discharge occurs when components other than oxides adhere to the gaps, which adversely affects the film formation process. In particular, in order to obtain a long cylindrical target, it is necessary to arrange a plurality of cylindrical target members in a row, and the number of gaps increases accordingly.

In view of the above circumstances, an object of the present invention is to provide a sputtering target in which particles and abnormal discharges are suppressed even if it is long and cylindrical, and a method for manufacturing the same.

In order to achieve the above object, the sputtering target according to one embodiment of the present invention includes a tubular backing tube, a target body, a bonding material, and a shielding member.
The target body includes a plurality of target members arranged side by side along the outer peripheral surface of the backing tube and having an arcuate cross section. Each of the plurality of target members is arranged so as to be separated from each other around the central axis of the backing tube. The gap formed between the target members arranged around the central axis extends in the central axis direction of the backing tube.
The joining material is provided between the backing tube and the target body, and joins the backing tube and each of the plurality of target members.
The shielding member is provided between the joining material and the target body, and shields the gap from the side of the joining material.

According to such a sputtering target, the target body includes a plurality of target members having an arcuate cross section, and each of the plurality of target members is arranged so as to be separated from each other around the central axis of the backing tube. The gap formed between the surrounding target members extends in the direction of the central axis of the backing tube. As a result, even if the sputtering target is long and cylindrical, the increase in the volume of the gap is suppressed, and particles and abnormal discharge are suppressed.

In the sputtering target, the target body surrounds the backing tube with a set of target members. When the set of target members is cut in a direction orthogonal to the central axis direction of the backing tube, the central axis of the backing tube is located between the pair of gaps formed between the set of target members. You may.

According to such a sputtering target, since the central axis of the backing tube is located in the pair of gaps formed between the set of target members, the volume of the gap is increased even if the sputtering target is long and cylindrical. Is suppressed, and particles and abnormal discharge are suppressed.

In the sputtering target, a plurality of target bodies may be arranged side by side in a row in the central axis direction of the backing tube.

According to such a sputtering target, the sputtering target is formed to be longer.

In the sputtering target, each of the plurality of target members may be composed of an oxide sintered body.

According to such a sputtering target, even if each of the plurality of target members is composed of an oxide sintered body, particles and abnormal discharge of the sputtering target are suppressed.

In the sputtering target, the sintered body may have In, Ga, and Zn.

According to such a sputtering target, since the sintered body has In, Ga, and Zn, a stable oxide semiconductor film is formed.

In order to achieve the above object, in the method for manufacturing a sputtering target according to one embodiment of the present invention, the outer peripheral surface orbiting the central axis is configured to have the same curvature as the outer peripheral surface of the backing tube, and protrudes outward from the outer peripheral surface. A columnar core rod having a convex portion, and when the outer peripheral surface is surrounded by a tubular mold, the space formed by the outer peripheral surface and the mold is formed around the central axis by the convex portion. The core rod defined in a plurality of spaces is prepared.
The plurality of space portions are formed by the core rod and the mold.
Powder is filled in each of the plurality of spaces.
By applying isotropic pressure to the powder through the mold, a molded product made of the powder is formed.
By heating the molded product, a sintered body in which the powder is sintered is formed.

According to such a method for manufacturing a sputtering target, even if the sputtering target is long and cylindrical, the increase in the volume of the gap is suppressed, and the sputtering target in which particles and abnormal discharge are suppressed can be reliably manufactured.

In the method for manufacturing a sputtering target, a pair of space portions that line up the space around the central axis may be defined by the convex portion.

According to such a method for manufacturing a sputtering target, since a pair of spaces in which the above spaces are arranged around the central axis are defined by the convex portion, the volume of the gap is increased even if the sputtering target is long and cylindrical. Sputtering target with suppressed particles and abnormal discharge is surely manufactured.

In the method for manufacturing a sputtering target, the support base is formed so that the longitudinal direction of the molded body formed by filling the pair of spaces is parallel to the support surface of the support base that supports the molded body. The above-mentioned molded product is placed on the
A support jig composed of the same components as the molded body is interposed between the contact surface where the molded body is in contact with the outer peripheral surface of the core rod and the support base.
The molded product may be fired while supporting the contact surface with the support jig.

According to such a method for manufacturing a sputtering target, the molded body is fired while the molded body is supported by a support jig composed of the same components as the molded body, so that the volume of the gap increases even if it is a cylindrical type. Sputtering targets that are suppressed, particles, and abnormal discharge are suppressed are reliably manufactured.

As described above, according to the present invention, there is provided a sputtering target in which particles and abnormal discharge are suppressed even if it is long and cylindrical, and a method for manufacturing the same.

FIG. (A) is a schematic perspective view of the sputtering target according to the present embodiment. FIG. (B) is a schematic cross-sectional view of the sputtering target according to the present embodiment. It is a schematic cross-sectional view which shows the cross-sectional structure of a shielding member. It is a schematic perspective view which shows the manufacturing jig used in the manufacturing method of a sputtering target. It is a schematic cross-sectional view which shows another manufacturing jig used in the manufacturing method of a sputtering target. FIG. (A) is a schematic perspective view showing a molded product that is a precursor of the target body. FIG. (B) is a schematic perspective view showing a state when the molded product is sintered. It is a schematic diagram which shows the state of filling the joint material between a target body and a backing tube. It is a schematic perspective view of the sputtering target which concerns on the modification 1 of this embodiment. It is a schematic sectional view of the sputtering target which concerns on the modification 2 of this embodiment. It is a schematic diagram which shows another state of filling a joint material between a target body and a backing tube.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. XYZ axis coordinates may be introduced in each drawing. Further, the same member or a member having the same function may be designated by the same reference numeral, and the description may be omitted as appropriate after the description of the member.

FIG. 1A is a schematic perspective view of the sputtering target according to the present embodiment. FIG. 1B is a schematic cross-sectional view of the sputtering target according to the present embodiment. FIG. 1 (b) shows a cross section in the XY axis plane of FIG. 1 (a).

The sputtering target 1 shown in FIGS. 1A and 1B is a cylindrical target assembly used for sputtering film formation. The sputtering target 1 includes a backing tube 10, a target main body 20, a bonding material 30, and a shielding member 40.

The backing tube 10 is a tubular body, and the inside thereof is hollow. The backing tube 10 extends in a uniaxial direction (for example, in the direction of the central axis 10c). The direction of the central axis 10c is the longitudinal direction of the backing tube 10. Further, since the backing tube 10 is the base material of the sputtering target 1, the central axis 10c is also the central axis of the sputtering target 1.

The backing tube 10 has an outer peripheral surface 101 that orbits around the central axis 10c, and an inner peripheral surface 102 that is located on the opposite side of the outer peripheral surface 101 and orbits around the central axis 10c. When the backing tube 10 is cut in a plane orthogonal to the central axis 10c (for example, an XY-axis plane), the shape thereof is, for example, an annular shape.

The material of the backing tube 10 has a material having excellent thermal conductivity, and is, for example, titanium (Ti), copper (Cu), or the like. A flow path through which the refrigerant flows may be appropriately formed inside the backing tube 10.

The target body 20 surrounds the outer peripheral surface 101 of the backing tube 10. The target body 20 is arranged concentrically with respect to the backing tube 10. The target body 20 has a plurality of target members. For example, in the examples of FIGS. 1A and 1B, the target body 20 has a set of

target members

20A and 20B.

Each of the

target members

20A and 20B surrounds the backing tube 10. For example, the

target members

20A and 20B are arranged side by side along the outer peripheral surface 101 of the backing tube 10. When each of the

target members

20A and 20B is cut along the XY axis plane, the shape thereof is, for example, an arc shape. For example, the cross-sectional shapes of the

target members

20A and 20B in the XY-axis plane have the same shape. Further, the lengths of the

target members

20A and 20B in the Z-axis direction are the same.

The

target members

20A and 20B are arranged so as to be separated from each other around the central axis 10c of the backing tube 10 without contacting each other. For example, the

target members

20A and 20B are arranged side by side around the central axis 10c of the backing tube 10. In other words, the target body 20 has a divided structure divided in a direction orthogonal to the central axis 10c. As a result, a gap (divided portion) 201 is formed between the target member 20A and the target member 20B.

For example, when the

target members

20A and 20B are cut in a direction orthogonal to the direction of the central axis 10c, a pair of gaps 201 are formed between the

target members

20A and 20B, respectively. Each of the pair of gaps 201 is parallel to each other and extends in the direction of the central axis 10c of the backing tube 10. Further, the central axis 10c of the backing tube 10 is located between the pair of gaps 201. For example, in the XY axis plane, the pair of gaps 201 and the central axis 10c are arranged in series.

The width of the gap 201 is not particularly limited, and is set so as not to come into contact with each other due to thermal expansion of the

target members

20A and 20B, for example.

The

target members

20A and 20B are made of the same material, for example, made of an oxide sintered body. As an example, the sintered body has In and Zn. For example, the sintered body is made of In—Ga—Zn—O (IGZO). For example, the sintered body may be an In—Ti—Zn—Sn—O (ITZTO) sintered body, an In—Ti—Zn—Sn—O (IGTO) sintered body, or the like.

The joining material 30 is interposed between the backing tube 10 and the target body 20. The joining material 30 is in close contact with the backing tube 10 and the target body 20. The joining material 30 joins the backing tube 10 and each of the plurality of

target members

20A and 20B. The bonding material 30 includes, for example, indium (In), tin (Sn), a solder material, and the like.

The shielding member 40 is provided between the joining material 30 and the target body 20. The shielding member 40 is located between the gap 201 and the joining member 30. The shielding member 40 shields the gap 201 from the side of the joining member 30. As a result, leakage of the bonding material 30 into the gap 201 is suppressed, and the bonding material 30 is less likely to enter the gap 201. Further, even if the gap 201 is exposed to plasma during sputtering, the bonding member 30 is shielded from the plasma by the shielding member 40. As a result, during sputtering, the component of the bonding material 30 (for example, In) is less likely to be mixed with the component of the target body 20.

The specific configuration of the shielding member 40 will be described below. 2 (a) and 2 (b) are schematic cross-sectional views showing a cross-sectional structure of a shielding member.

The shielding member 40 may be the shielding member 40A shown in FIG. 2A or the shielding member 40B shown in FIG. 2B.

The shielding member 40A shown in FIG. 2A has an adhesive sheet 401 having adhesiveness and a resin sheet 402 having plasma resistance. The resin sheet 402 is provided between the

target members

20A and 20B and the adhesive sheet 401. The resin sheet 402 is a shielding base material for the shielding member 40A. The adhesive sheet 401 is a sticking material for the shielding member 40A.

The resin sheet 402 straddles the gap 201, and a part of the resin sheet 402 is exposed in the gap 201. The resin sheet 402 is attached to each of the

target members

20A and 20B by the adhesive sheet 401 from the side of the bonding material 30. Each material of the pressure-sensitive adhesive sheet 401 and the resin sheet 402 includes, for example, polyimide, fluororesin, silicone resin, and the like.

The shielding member 40B shown in FIG. 2B has an adhesive sheet 401, a metal sheet 403, and an oxide layer 404. The shielding member 40B has a laminated structure in which the adhesive sheet 401 / metal sheet 403 / oxide layer 404 are arranged in this order from the bonding material 30 toward the

target members

20A and 20B. In the shielding member 40B, the metal sheet 403 joins the pressure-sensitive adhesive sheet 401 and the oxide layer 404 and functions as an intermediate layer for relieving the stress of each, and the oxide layer 404 functions as a shielding base material.

The oxide layer 404 straddles the gap 201, and a part of the oxide layer 404 is exposed in the gap 201. Further, the oxide layer 404 is attached to the

target members

20A and 20B from the side of the bonding material 30 by the adhesive sheet 401 via the metal sheet 403.

The metal sheet 403 contains, for example, titanium (Ti). The oxide layer 404 is made of the same material as the

target members

20A and 20B. As a result, even if the shielding member 40B is exposed to plasma during sputtering, components other than the components of the target body 20 are less likely to be mixed in the coating film.

The manufacturing method of the sputtering target 1 will be described.

FIG. 3 is a schematic perspective view showing a manufacturing jig used in a method for manufacturing a sputtering target.

First, the columnar core rod 5 shown in FIG. 3 is prepared. The core rod 5 extends in the direction of the central shaft 5c, and the direction of the central shaft 5c is the longitudinal direction of the core rod 5. In the core rod 5, the outer peripheral surface 51 orbits the central axis 5c, and the outer peripheral surface 51 has the same curvature as the outer peripheral surface 101 of the backing tube 10. Further, the core rod 5 is provided with a convex portion 52 protruding outward from the outer peripheral surface 51 on the outer peripheral surface 51. For example, a plurality of convex portions 52 are provided on the outer peripheral surface 51. For example, in the example of FIG. 3, a pair of convex portions 52 are provided around the central axis 5c at intervals of 180 degrees.

4 (a) and 4 (b) are schematic cross-sectional views showing another manufacturing jig used in the method for manufacturing a sputtering target. 4 (a) and 4 (b) show the XY-axis cross sections of the manufacturing jig.

Next, as shown in FIG. 4A, a tubular mold 6 is prepared. The mold 6 extends in the direction of the central axis 5c, and at least one of both ends thereof is closed. When the core rod 5 is surrounded by the tubular mold 6, a plurality of space portions 53 are formed between the core rod 5 and the mold 6. For example, when the outer peripheral surface 51 of the core rod 5 is surrounded by the mold 6, the pair of convex portions 52 abuts on the inner wall 6w of the mold 6. As a result, the space between the outer peripheral surface 51 and the mold 6 is defined by a plurality of space portions 53.

For example, in the example of FIG. 4A, the space between the outer peripheral surface 51 and the mold 6 is defined by the pair of convex portions 52 in the pair of space portions 53 around the central axis 5c. The pair of space portions 53 are arranged around the central axis 5c.

Next, as shown in FIG. 4B, each of the plurality of space portions 53 is filled with the powder 21 which is the raw material of the target main body 20. Subsequently, the powder 21 is isotropically pressed from the outside of the mold 6 by a method such as cold isostatic pressing (CIP) (see the arrow).

FIG. 5A is a schematic perspective view showing a molded product that is a precursor of the target body. FIG. 5B is a schematic perspective view showing a state when the molded product is sintered.

By isotropically applying pressure to the powder 21 via the mold 6, as shown in FIG. 5A, a pair of molded bodies 22 made of the powder 21 are formed.

Next, as shown in FIG. 5B, a support base 70 for supporting the molded body 22 is prepared. Subsequently, the molded body 22 is placed on the support base 70 so that the longitudinal direction of the molded body 22 is parallel to the support surface 71 of the support base 70.

Next, a support jig 72 composed of the same components as the molded body 22 is interposed between the contact surface (inner wall) 22w of the molded body 22 that is in contact with the outer peripheral surface 51 of the core rod 5 and the support base 70. Let me. The support jig 72 is in the form of a block, and at least one is prepared. Subsequently, the molded body 22 is heated while the contact surface 22w is supported by the support jig 72. As a result, sintered bodies in which the powder 21 is fired, that is,

target members

20A and 20B are formed. Here, since the support jig 72 is composed of the same components as the molded body 22, foreign matter does not enter the sintered body from the support jig 72.

FIG. 6 is a schematic view showing how the bonding material is filled between the target body and the backing tube.

Next, the

target members

20A and 20B are arranged around the backing tube 10 with the backing tube 10 leaning against it. Subsequently, the molten bonding material 30 is filled between the backing tube 10 and the

target members

20A and 20B from below the backing tube 10 (for example, 160 ° C., In). In filling of the bonding material 30, filling, press-fitting, etc. using the pressure (gravity) difference are used. At this time, since the gap 201 is shielded by the shielding member 40, the joining material 30 is less likely to leak into the gap 201.

After that, the joining material 30 is solidified between the backing tube 10 and the

target members

20A and 20B, and the backing tube 10 and the

target members

20A and 20B are joined by the joining material 30. After that, if necessary, a finishing process for adjusting the surface roughness of the

target members

20A and 20B is performed.

An example of the effect when the sputtering target 1 is used will be described.

In a cylindrical oxide target having a non-divided structure, when the molded body is fired, the molded body is placed in a high temperature environment, so that the molded body is distorted due to softening, shrinkage, etc. of the molded body. There is. For this reason, when producing a cylindrical oxide target having a non-divided structure, a method of firing in an upright cylindrical molded body may be adopted.

However, when firing the molded body in an upright position, the length of the sintered body (target member) formed is limited by the height of the firing furnace. Therefore, in order to obtain a sintered body having a length of 1 m or more, a new vertically long firing furnace must be newly introduced, which causes a cost problem. Further, if the molded product is fired in an upright state, the sintered body is more likely to be distorted or collapsed. For this reason, the yield is lowered in the cylindrical oxide target having an undivided structure.

On the other hand, in the present embodiment, the molded body 22 has a semi-cylindrical shape. As a result, when the molded body 22 is fired, the molded body 22 can be placed horizontally, the molded body 22 is less likely to be distorted, and the molded body 22 is less likely to collapse. As a result, the yield of the oxide target is greatly improved. Further, by placing the molded body 22 horizontally, a long target member can be obtained, and further, since the height of the firing furnace is not limited, it is not necessary to newly introduce a firing furnace. As a result, cost reduction is realized. In particular, the method of the present embodiment is effective when forming a sputtering target of IGZO (indium-gallium-zinc-oxide) or the like, which is an oxide semiconductor material.

Also, if multiple gaps are formed in the direction orthogonal to the central axis of the long sputtering target, the volume of the gaps exposed to plasma during sputtering will inevitably increase. Therefore, the component of the bonding material or the component of the backing tube may be mixed into the coating film through the gap. The inclusion of such impurities may lead to deterioration of the quality of the coating film in the future, or the characteristics of the coating film may vary.

On the other hand, in the present embodiment, since the gap 201 is formed in the longitudinal direction of the sputtering target 1, the volume of the gap exposed to plasma is reduced. In particular, by arranging the pair of

semi-cylindrical target members

20A and 20B around the backing tube 10, the volume of the gap exposed to plasma is greatly reduced. As a result, impurities are less likely to be mixed into the film, and a high-quality film can be formed. Further, the characteristics of the coating film are less likely to vary.

Further, since the gap 201 is shielded from the side of the bonding material 30 by the shielding member 40, leakage of the bonding material 30 into the gap 201 and plasma irradiation of the bonding material 30 are reliably suppressed.

(Modification example 1)

FIG. 7 is a schematic perspective view of the sputtering target according to the first modification of the present embodiment.

In the sputtering target 2, a plurality of target bodies 20 are arranged side by side in a row in the direction of the central axis 10c of the backing tube 10. Each of the plurality of target bodies 20 is arranged apart from each other in the direction of the central axis 10c. The length of the sputtering target 2 having the plurality of target bodies 20 in the direction of the central axis 10c is 2000 mm or more.

The gap 202 of the target main body 20 adjacent to each other in the direction of the central axis 10c may be narrower than the gap 201. As a result, even if a plurality of target bodies 20 are stacked in the direction of the central axis 10c, the volume of the gap does not become excessive.

According to such a configuration, in addition to the above-mentioned effect, the length of the sputtering target in the direction of the central axis 10c can be easily increased.

(Modification example 2)

8 (a) and 8 (b) are schematic cross-sectional views of the sputtering target according to the second modification of the present embodiment.

In the target body 20, a recess 203 communicating with the gap 201 may be provided inside the target body 20. The recess 203 is formed on the side of the backing tube 10. The shielding member 40A (FIG. 8A) or the shielding member 40B (FIG. 8B) is housed in the recess 203.

With such a configuration, the space between the shielding member 40A (or the shielding member 40B) and the backing tube 10 is surely secured. As a result, the molten bonding material 30 is evenly distributed between the backing tube 10 and the target body 20 without being loaded by the shielding member 40A (or the shielding member 40B).

FIG. 9 is a schematic view showing another state in which the bonding material is filled between the target body and the backing tube.

For example, when the bonding material 30 is injected from below between the backing tube 10 and the target body 20 with the backing tube 10 and the target body 20 placed horizontally, the molten bonding material 30 is formed. The backing tube 10 and the target main body 20 are evenly distributed without being loaded by the shielding member 40A (or the shielding member 40B).

[Target member]

(Example)

As raw materials, In ₂ O ₃ powder having an average particle size of primary particles of 1.1 μm, ZnO powder having an average particle size of primary particles of 0.5 μm, and an average particle size of primary particles of 1.3 μm. Ga ₂ O ₃ was weighed so that the molar ratio of oxides was 1: 2: 1. These raw material powders were pulverized and mixed with a wet ball mill. A zirconia ball having a diameter of 5 mm was used as the crushing medium. The pulverized and mixed slurry was dried and granulated with a spray dryer to obtain granulated powder.

The polyurethane mold 6 in which the metal core rod 5 was installed was filled with the granulated powder, the granulated powder was sealed, and then CIP molding was performed at a pressure of 98 MPa. As a result, two semi-cylindrical molded bodies (molded bodies) 22 were obtained. At the same time, the support jig 72 was molded. The dimensions of the support jig 72 are width 40 mm × height 77 mm.

The molded body 22 was left to stand sideways in a degreasing furnace and degreased at 600 ° C. After the degreasing treatment was completed, the molded body 22 was placed sideways on the support base 70 made of alumina, and the molded body 22 was supported by three support jigs 72 arranged in a row on the support base 70. As for the number of samples of the molded body 22, a total of 20 molded bodies (2 in one molding) were produced by performing molding 10 times.

Each of the molded bodies 22 was heat-treated at a maximum temperature of 1500 ° C. for 10 hours in a firing furnace to obtain

semi-cylindrical target members

20A and 20B having a length of 1050 mm. The average strain of the inner diameters of the 20 target members after firing was 1.1 mm.

(Comparative example 1)

The granulated powder produced under the same conditions as in the examples was filled between the round bar-shaped metal core rod and the mold 6 in which the convex portion 52 was not provided. After sealing the granulated powder, CIP molding was performed at a pressure of 98 MPa to obtain a cylindrical molded body having no gap 201. The obtained molded body (molded body) was degreased at 600 ° C. in a degreasing furnace in an upright state. As for the number of samples of the molded body, a total of 10 molded bodies (1 in one molding) were produced by performing the molding 10 times.

The molded product after the degreasing treatment was left standing on a support 70 and fired at a maximum temperature of 1500 ° C. for 10 hours in a firing furnace. As a result, a cylindrical target member having a length of 350 mm was obtained.

The average strain of the inner diameters of the 10 target members was 2 mm, which was larger than that of the examples. It is considered that one of the reasons for this is that the shrinkage during firing was hindered by the frictional resistance of the end face that was in contact with the support 70, and the difference in inner diameter from the upper end face became large. ..

(Comparative example 2)

The granulated powder produced under the same conditions as in Example 1 was CIP molded and degreased under the same conditions as in Comparative Example 1 to obtain a cylindrical molded body. The molded product after the degreasing treatment was allowed to stand sideways on the support 70 and fired at a maximum temperature of 1500 ° C. for 10 hours in a firing furnace to obtain a cylindrical target member having a length of 1050 mm. As for the number of samples of the molded body, a total of 10 molded bodies (1 in one molding) were produced by performing the molding 10 times.

Of the 10 target members, 4 target members were cracked. The average strain of the inner diameters of the remaining six target members without cracks was 10 mm, which was larger than that of Comparative Example 1. As one of the factors, it is considered that in the case of standing sideways, the strain becomes large due to its own weight when it shrinks during firing.

Table 1 summarizes the number of CIP-molded compacts in Examples 1 and 2, the number of target members that did not crack, and the distortion of the inner diameter.

[Sputtering target]

The

semi-cylindrical target members

20A and 20B obtained in the examples were machined so as to have an inner diameter of 135 mm, an outer diameter of 147 mm and a length of 1000 mm, and a set of

target members

20A and 20B was prepared. Further, a shielding member 40 having a width of 5 mm was produced by laminating an oxide layer 404 (IGZO layer) on a metal sheet 403 made of Ti having a thickness of 0.2 mm by plasma spraying.

A set of

target members

20A and 20B were opposed to each other so as to form a cylinder, and a shielding member 40 was attached to the gap 201 from the inside. Subsequently, the backing tube 10 was arranged inside the

cylindrical target members

20A and 20B (target body 20). The inner peripheral surface 102 of the backing tube 10 was pretreated by rubbing In while applying ultrasonic vibration with a trowel equipped with an ultrasonic transmitter.

After aligning the target body 20 and the backing tube 10 so as to be concentric, the molten In bonding material 30 was injected between the target body 20 and the backing tube 10. After that, the bonding material 30 was cooled and solidified.

The width of the gap 201 of the obtained sputtering target 1 was 0.3 mm. As a result of observing the gap 201 with a microscope, no leakage of the bonding material 30 was observed.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made. Each embodiment is not limited to an independent form and can be combined as technically possible as possible.

1, 2 ... Sputtering target 5 ... Core rod 5c ... Central axis 51 ... Outer surface 52 ... Convex 53 ... Space 6 ... Type 6w ... Inner wall 10 ... Backing tube 10c ... Central axis 101 ... Outer surface 102 ... Inner peripheral surface 20 ...

Target body

20A, 20B ...

Target member

201, 202 ... Gap 21 ... Powder 22 ... Molded body 22w ... Contact surface 30 ...

Bonding material

40, 40A, 40B ... Shielding member 401 ... Adhesive sheet 402 ... Resin sheet 403 ... Metal Sheet 404 ... Oxide layer 70 ... Support stand 71 ... Support surface 72 ... Support jig

Claims

With a tubular backing tube
A plurality of target members arranged side by side along the outer peripheral surface of the backing tube and having an arcuate cross section are included, and each of the plurality of target members is arranged so as to be separated from each other around the central axis of the backing tube. A target body in which a gap formed between target members arranged around the central axis extends in the central axis direction of the backing tube,
A joining material provided between the backing tube and the target body and joining the backing tube and each of the plurality of target members.
A sputtering target provided between the bonding material and the target main body and provided with a shielding member that shields the gap from the side of the bonding material.
In the sputtering target according to claim 1,
The target body surrounds the backing tube with a set of target members.
When the set of target members is cut in a direction orthogonal to the central axis direction of the backing tube, the central axis of the backing tube is located between the pair of gaps formed between the set of target members. Sputtering target.
In the sputtering target according to claim 1 or 2.
A plurality of target main bodies are arranged side by side in a row in the central axis direction of the backing tube.
In the sputtering target according to any one of claims 1 to 3.
Each of the plurality of target members is a sputtering target composed of an oxide sintered body.
In the sputtering target according to claim 4,
The sintered body is a sputtering target having In, Ga, and Zn.
A sputtering target having a tubular backing tube, a target body surrounding the backing tube, and a bonding material interposed between the backing tube and the target body and joining the backing tube and the target body. It ’s a manufacturing method,
A columnar core rod having an outer peripheral surface orbiting the central axis having the same curvature as the outer peripheral surface of the backing tube and having a convex portion protruding outward from the outer peripheral surface, and the outer peripheral surface is formed by a tubular mold. The core rod is prepared so that the space formed by the outer peripheral surface and the mold is defined by the convex portion in a plurality of space portions around the central axis when the outer peripheral surface and the mold are surrounded.
The plurality of space portions are formed by the core rod and the mold.
Each of the plurality of spaces is filled with powder, and
By applying isotropic pressure to the powder through the mold, a molded product made of the powder is formed.
A method for producing a sputtering target, which forms a sintered body in which the powder is sintered by heating the molded body.
In the method for manufacturing a sputtering target according to claim 6.
A method for manufacturing a sputtering target, in which the space is defined by the convex portion in a pair of space portions arranged around the central axis.
In the method for manufacturing a sputtering target according to claim 6 or 7.
The molded body is placed on the support so that the longitudinal direction of the molded body formed by filling the pair of spaces is parallel to the support surface of the support that supports the molded body.
A support jig composed of the same components as the molded body is interposed between the contact surface where the molded body is in contact with the outer peripheral surface of the core rod and the support base.
A method for manufacturing a sputtering target in which a molded product is fired while supporting the contact surface with the support jig.