WO2021084838A1

WO2021084838A1 - Gap-filling member

Info

Publication number: WO2021084838A1
Application number: PCT/JP2020/030212
Authority: WO
Inventors: 矢野　智泰; 打田　龍彦; 享祐寺村; 賢太郎廣藤
Original assignee: 三井金属鉱業株式会社
Priority date: 2019-11-01
Filing date: 2020-08-06
Publication date: 2021-05-06
Also published as: TWI813913B; TW202118887A

Abstract

Provided is a novel gap-filling member with a laminated structure that is hardly delaminated by heat.　When a plurality of target members are placed on the surface side of the substrate of a sputtering target (will be simply referred to as "substrate"), a gap-filling member is interposed between the target members and the substrate along gaps formed between adjacent targets. The gap-filling member is characterized by having a multilayered structure including at least three layers in the thickness direction, the multilayered structure including an intermediate layer between a layer on the target member side (also referred to as "front face layer") and a layer on the substrate side (also referred to as "reverse face layer"), the intermediate layer being made of a material having a linear expansivity between the linear expansivity of the material of the front face layer and the linear expansivity of the material of the reverse face layer.

Description

Gap placement member

The present invention relates to adjacent targets in a split target in which a plurality of target members are arranged on the surface side of a base material (simply referred to as "base material") of a sputtering target with a gap between the adjacent target members. The present invention relates to a gap arranging member that can be arranged along a gap between the members and can be interposed between the target member and the base material so that the base material is not exposed to the surface side in the gap.

Sputtering is a method of thin film forming technology. As an example, an inert gas such as Ar is introduced into a vacuum, a negative voltage is applied to the target member to generate a glow discharge, and the inert gas is turned into plasma by the glow discharge and ionized to form a gas ion. , This gas ion is made to collide with the surface of the target at high speed to eject the particles of the film-forming material constituting the target, and the particles are adhered and deposited on the surface of the base material forming the thin film to be dense and strong. Examples thereof include a method of forming a thin film on the surface of a base material.
According to such a sputtering method, it is possible to form a thin film having a large area with high accuracy, in addition to being able to form a film even on a material such as a refractory metal, an alloy, or a ceramic which is difficult to form a film by a vacuum vapor deposition method or the like. Therefore, the sputtering method is often used for manufacturing various electronic parts such as information devices, AV devices, and home appliances. Thin films such as ITO, IZO, and IGZO formed by the sputtering method are widely used as electrodes for display devices such as liquid crystal displays, touch panels, and EL displays.

In recent years, with the increase in size of display panels, it has become necessary to form a thin film having a large area, and it is also necessary to increase the size of target members. However, it is difficult to form the target member used for sputtering with a single target member having a large area. Therefore, a method is adopted in which a target member is divided into a plurality of target members and a plurality of target members are joined onto a base material to obtain a large-area sputtering target (see, for example, Patent Document 1).

In this way, the target divided into a plurality of target members (also referred to as “divided target”) is placed between adjacent target members on the base material in consideration of the difference in thermal expansion between the base material and the target member. It is generally arranged so as to form a gap, and the base material and each target member are generally joined by a low melting point solder having good thermal conductivity such as an In-based metal or a Sn-based metal.

In the split sputtering target in which a plurality of oxide semiconductor target members are joined together, a gap is provided between the target members as described above, so that the base material is exposed in the gap. There is a concern that the base material is also sputtered during sputtering and is mixed in the thin film of the oxide semiconductor to be formed. Therefore, a method has been proposed in which a protective member (corresponding to the gap arrangement member of the present invention) is provided in the gap between adjacent target members so that the base material is not exposed (see, for example, Patent Document 2).

Japanese Unexamined Patent Publication No. 2005-232580 International Publication No. 2012/0653524 Pamphlet

Patent Document 2 describes a two-layer structure as a protective member (corresponding to the gap arrangement member of the present invention) that protects the surface of the base material from sputtering by preventing the base material from being exposed in the gap between adjacent target members. Is disclosed. That is, a second protective member formed of a metal foil made of a metal such as Cu or an alloy, which is arranged on the base material side, and a kind of elements contained in the target member, which is arranged on the upper side thereof, that is, on the target member side. A protective member having a two-layer structure including a first protective member formed of a metal, alloy or ceramic material including the above is disclosed.
However, when such a protective member having a two-layer structure (corresponding to the gap arrangement member of the present invention) is heated by sputtering or the like, due to the difference in linear expansion coefficient between the second protective member and the material constituting the first protective member. Delamination may occur.

Therefore, in the present invention, regarding the gap arrangement member having a laminated structure, the protective member (corresponding to the gap arrangement member of the present invention) disclosed in Patent Document 2 is improved, and delamination is unlikely to occur even by heating such as sputtering. It is intended to provide a new gap arrangement member.

In the present invention, when a plurality of target members are arranged on the surface side of a base material (simply referred to as "base material") of a sputtering target, the target member and the base material are brought into contact with each other along a gap between adjacent target members. It is a gap arrangement member that is interposed between them.
It has a multi-layered structure in which three or more layers are laminated in the thickness direction, and is intermediate between the layer on the target member side (also referred to as "front surface layer") and the layer on the base material side (also referred to as "back surface layer"). The coefficient of linear expansion of the material provided with the layer and constituting the intermediate layer is within a range between the coefficient of linear expansion of the material constituting the front surface layer and the coefficient of linear expansion of the material constituting the back surface layer. We propose a featured gap arrangement member.

The gap arrangement member proposed by the present invention has a multi-layer structure in which three or more layers are laminated, and the linear expansion coefficient of the material constituting the intermediate layer is the linear expansion coefficient of the material constituting the front surface layer and the back surface. Since it is adjusted so as to be within the range of the coefficient of linear expansion of the material constituting the layer, the difference in the coefficient of linear expansion between each layer becomes small, and delamination is unlikely to occur even by heating such as sputtering. Can be done.

It is a top view perspective view which showed the outline of an example of a split target. It is a vertical cross-sectional view which showed a part of the example of the sputtering target which arranges the gap arrangement member which concerns on one example of this invention. It is sectional drawing which showed the outline of the gap arrangement member which concerns on an example of this invention.

Next, the present invention will be described based on an example embodiment. However, the present invention is not limited to the embodiments described below.

<This gap arrangement member>
As shown in FIGS. 1 and 2, the gap arranging member (referred to as “the present gap arranging member”) 1 according to an example of the embodiment of the present invention has a plurality of target members 3 adjacent to each other on the surface side of the base material 2. In a split target having a configuration in which a gap 4 is provided between the

matching target members

3 and 3, the target member 3 and the base material 2 are provided along the gap 4 between the

adjacent target members

3 and 3. It is a gap arranging member that is interposed between the target members 3, in other words, is arranged along the gap 4 between the

adjacent target members

3, 3 and is interposed between the target member 3 and the base material 2.

Since the gap arranging member 1 can cover the surface of the base material 2 along the gap 4 between the

adjacent target members

3 and 3, the surface of the base material 2 is sputtered in the gap 4 during sputtering. It is possible to effectively prevent the constituent material of the base material 2 from being mixed in the thin film to be formed.

As shown in FIG. 3, the gap arrangement member 1 may have a multilayer structure in which three or more layers are laminated in the thickness direction. That is, one layer or two or more intermediate layers 1B can be provided between the layer on the target member side, that is, the front surface layer 1A, and the layer on the base material 2 side, that is, the back surface layer 1C.

(Coefficient of linear expansion)
The coefficient of linear expansion of the material constituting the intermediate layer 1B is preferably within the range between the coefficient of linear expansion of the material constituting the front surface layer 1A and the coefficient of linear expansion of the material constituting the back surface layer 1C. In this case, "within the range" means that the coefficient of linear expansion of the material constituting the intermediate layer 1B is the same as the coefficient of linear expansion of the material constituting the surface layer 1A, or the coefficient of linear expansion of the material constituting the intermediate layer 1B is the back surface. This includes the case where the coefficient of linear expansion of the material constituting the layer 1C is the same.
For example, the gap arrangement member 1 has a three-layer structure in which the first protective layer (front surface layer 1A), the second protective layer (intermediate layer 1B), and the third protective layer (back surface layer 1C) are laminated in this order from the front surface side. In the case of, the coefficient of linear expansion of the material constituting each layer is preferably 1st protective layer ≤ 2nd protective layer ≤ 3rd protective layer, and among them, 1st protective layer <2nd protective layer <3rd protective layer. More preferably.
Further, the gap arrangement member 1 has a first protective layer (front surface layer 1A), a second protective layer (intermediate layer 1B), a third protective layer (intermediate layer 1B), and a fourth protective layer (back surface layer 1C) in this order. In the case of a four-layer structure formed by stacking, the linear expansion coefficient of the material constituting each layer is preferably 1st protective layer ≤ 2nd protective layer ≤ 3rd protective layer ≤ 4th protective layer, and among them, 1st protection. It is more preferable that the layer <second protective layer <third protective layer <fourth protective layer.

The difference in the coefficient of linear expansion of the materials constituting the intermediate layer 1B and the front surface layer 1A, and the intermediate layer 1B and the back surface layer 1C ^{is preferably 9.0 × 10 -6} / K or less, and 7.0 × 10 among them. ^-6 / K or less, further preferably 5.0 × 10 ^-6 / K or less therein.

Further, from the viewpoint of preferably ensuring the bonding between the gap arranging member 1 and the base material 2, the difference in linear expansion coefficient between the back surface layer 1C of the gap arranging member 1 and the materials constituting the base material 2 is 9.0. × but preferably not more than ^{10 -6 / K, 7.0 × 10} -6 / K or less among them, 5.0 × 10 ^-6 / K or less among them, 3.0 × 10 ^-6 / K among them Hereinafter, among them, ^{it is more preferably 1.0 × 10 -6} / K or less, and particularly preferably the same.

(shape)
Examples of the plan view shape of the gap arrangement member 1 include a rectangular shape, a band shape, a cross band shape, and a lattice frame shape. However, it is not limited to these plan-view shapes.

(Layer thickness)
The thickness of the back surface layer 1C is preferably the same as or larger than the thickness of the front surface layer 1A from the viewpoint of suppressing warpage due to the difference in thermal expansion coefficient and warping against stress during formation of the protective film. ..
At this time, the difference in thickness between the back surface layer 1C and the front surface layer 1A is preferably 0 mm or more and 1.0 mm or less, and more preferably 0.8 mm or less, and more preferably 0.5 mm or less.

The thickness of the back surface layer 1C is preferably the same as or larger than the thickness of the intermediate layer 1B from the viewpoint of warping due to the difference in the coefficient of thermal expansion and warping against stress during formation of the protective film.
At this time, the difference in thickness between the back surface layer 1C and the intermediate layer 1B is preferably 0 mm or more and 1.0 mm or less, and more preferably 0.8 mm or less, and more preferably 0.5 mm or less.

The thickness of the intermediate layer 1B is preferably the same as or larger than the thickness of the surface layer 1A from the viewpoint of obtaining the effect of alleviating the difference in thermal expansion between the front surface layer 1A and the back surface layer 1C.
At this time, the difference in thickness between the intermediate layer 1B and the surface layer 1A is preferably 0 mm or more and 0.5 mm or less, and more preferably 0.3 mm or less, and more preferably 0.1 mm or less.

Therefore, for example, the gap arrangement member 1 has a three-layer structure in which the first protective layer (front surface layer 1A), the second protective layer (intermediate layer 1B), and the third protective layer (back surface layer 1C) are laminated in this order. In this case, the thickness of each layer is preferably at least 1st protective layer ≤ 3rd protective layer, and more preferably 1st protective layer <3rd protective layer. Further, it is preferable that the first protective layer ≦ the second protective layer ≦ the third protective layer, and it is more preferable that the first protective layer <the second protective layer <the third protective layer.
Further, the gap arrangement member 1 has a first protective layer (front surface layer 1A), a second protective layer (intermediate layer 1B), a third protective layer (intermediate layer 1B), and a fourth protective layer (back surface layer 1C) in this order. In the case of a four-layer structure formed by stacking, the thickness of each layer is preferably at least the first protective layer ≤ the fourth protective layer, and among them, the first protective layer <the fourth protective layer is preferable. Further, it is preferable that the first protective layer ≤ the second protective layer ≤ the third protective layer ≤ the fourth protective layer, and among them, the first protective layer <the second protective layer <the third protective layer <the fourth protective layer. Is more preferable.

Further, since the surface layer 1A of the gap arrangement member 1 needs to withstand the collision of gas ions at least while the target member 3 is sputtering, the thickness of the surface layer 1A is the thickness of the target member 3. It is preferably 0.2% or more, and more preferably 0.5% or more, and more preferably 1.0% or more. On the other hand, from the viewpoint of the thickness of the bonder layer and the cooling efficiency, it is preferably 20% or less of the thickness of the target member 3, and more preferably 10% or less, and more preferably 5% or less.

The thickness of each layer itself is preferably set appropriately from the size of the target member 3 and the like.
As a guide, the thickness of the surface layer 1A may be, for example, 0.05 mm or more and 0.5 mm or less, particularly 0.1 mm or more or 0.3 mm or less, and particularly 0.2 mm or less.
Examples of the thickness of the back surface layer 1C include 0.2 mm or more and 1.0 mm or less, particularly 0.8 mm or less, and particularly 0.5 mm or less.
Examples of the thickness of the intermediate layer 1B include 0.05 mm or more and 0.5 mm or less, particularly 0.1 mm or more or 0.3 mm or less, and particularly 0.2 mm or less.
Further, as a guideline for the thickness of the entire gap arrangement member 1, 0.3 mm or more and 2 mm or less, particularly 0.4 mm or more or 1.5 mm or less, and 1.0 mm or less among them can be mentioned.

(material)
The surface layer 1A of the gap arranging member 1 is preferably made of a material that does not adversely affect the thin film to be formed or that can suppress the sputtering phenomenon.
As a material that does not adversely affect the thin film to be formed, for example, all or a part of the elements constituting the composition of the target member 3, alloys and oxides containing these elements, and the like can be used. ..
On the other hand, as a material capable of suppressing the sputtering phenomenon, for example, a substance having a volume resistance larger than that of the target member 3, that is, a high resistance substance can be used as a material of the gap arrangement member. When such a high resistance substance is used as a material for the gap arrangement member, it is preferable that the volume resistivity (Ω · cm) of the high resistance substance has a value of 10 times or more the volume resistivity of the target member 3. ..
More specifically, the surface layer 1A is preferably formed of a metal material, a ceramic material, a polymer material, or a composite material of two or more of these, which constitute the target member 3.
At this time, the ceramic material is a ceramic material having the same composition as the target member 3, a ceramic material having a part of the same composition as the target member 3, or a ceramic material having high resistance such as _{ZrO 2} and Al ₂ O _3. Is preferable. If the ceramic material has a high resistance, the invasion of plasma into the divided portion is suppressed during sputtering, and the sputtering of Zr or Al can be effectively prevented.

The material constituting the back surface layer 1C of the gap arrangement member 1 is preferably a material having a small difference in linear expansion coefficient from the base material 2 and does not react with the bonding material (for example, In solder).
From this point of view, the back surface layer 1C is preferably formed of a metal material, a ceramic material, or a composite material thereof.

The intermediate layer 1B of the gap arrangement member 1 may be a material that can be laminated with the front surface layer 1A and the back surface layer 1C, and the linear expansion coefficient can be adjusted within the above range.
Therefore, the intermediate layer 1B is preferably formed of a metal material, a ceramic material, or a composite material thereof.

Here, as the metal material constituting the target member 3, for example, if the target member 3 is IGZO (In—Ga—Zn—O), any one or more of In, Zn and Ga may be used. If the target member 3 is IZO (In—Zn—O), it is a metal material of In or Zn.

Examples of the ceramic material include a material made of an oxide or a nitride containing at least one of In, Zn, Al, Ga, Zr, Ti, Sn, and Mg. Specifically, for example, In ₂ O ₃ , ZnO, Al ₂ O ₃ , ZrO ₂ , TiO ₂ , IZO, IGZO and the like, ZrN, TiN, AlN, GaN, ZnN, InN and the like can be mentioned.

Examples of the polymer material include synthetic resin materials such as phenol resin, melamine resin, epoxy resin, urea resin, vinyl chloride resin, polyethylene and polypropylene, and general-purpose plastic materials such as polyethylene, polyvinyl chloride, polypropylene and polystyrene. Examples thereof include semi-general-purpose plastic materials such as polyvinyl acetate, ABS resin, AS resin, and acrylic resin. Further, engineering plastics such as polyacetal, polycarbonate, modified polyphenylene ether (PPE) and polybutylene terephthalate, and super engineering plastics such as polyarylate, polysulfone, polyphenylene sulfide, polyether ether ketone, polyimide resin and fluororesin can also be used. In particular, polyimide resin and the like are preferable because they also have a tape-like material and have high heat resistance and insulating properties.
Since such a polymer material is a high-resistance substance, the sputtering phenomenon in the gap 4 between the

target members

3 and 3 can be suppressed during sputtering, and an adverse effect on the thin film to be formed can be prevented.

For example, in the case of a three-layer structure in which the gap arranging member 1 is laminated in the order of the first protective layer (front surface layer 1A), the second protective layer (intermediate layer 1B), and the third protective layer (back surface layer 1C). The surface layer 1A is formed of a single metal or alloy or ceramic material containing one or more of the elements contained in the target member 3, the intermediate layer 1B is formed of a metal material or ceramic material, and the back surface layer 1C is also formed of a metal material or a metal material or It is preferable to adjust the linear expansion coefficient of the material formed from the ceramic material and constituting each layer so as to be within the above range.

(Manufacturing method of this gap arrangement member)
As an example of the method for manufacturing the gap arrangement member 1, a material for forming the back surface layer 1C, that is, a metal material, a ceramic material, or a tape, a sheet, a film, or a foil made of a composite material thereof is formed or prepared. Using a material for forming the intermediate layer 1B on the surface of the back surface layer 1C, the intermediate layer 1B is formed by using a known film forming method such as a vapor deposition method, a plating method, a sputtering method, a plasma spraying method, or a coating method. It may be formed and the surface layer 1A may be formed in the same manner as the intermediate layer 1B. However, it is not limited to these manufacturing methods.

<Target member>
It is preferable that the target member 3 to which the gap arranging member 1 is applied is arranged with a gap 4 provided between the

adjacent target members

3 and 3.
At this time, the gap 4 is usually about 0.2 mm to 0.5 mm.

The target member 3 preferably has a plate shape or a cylindrical shape having a square surface. However, it is not limited to these shapes.

The material of the target member 3 is not particularly limited. For example, a target for an oxide semiconductor composed of an oxide containing any one or more of Cu, Al, In, Sn, Ti, Ba, Ca, Zn, Mg, Ge, Y, La, Al, Si, Ga, and W, Examples include a transparent electrode target (ITO and the like) and a metal target such as Al.
Examples of the target for oxide semiconductors include In—Ti—O, In—Ga—Zn—O, Ga—Zn—O, In—Zn—O, In—W—O, and In—Zn—WO. , Zn-O, Sn-Ba-O, Sn-Zn-O, Sn-Ti-O, Sn-Ca-O, Sn-Mg-O, Zn-Mg-O, Zn-Ge-O, Zn-Ca -O, Zn-Sn-Ge-O, Cu ₂ O, CuAlO ₂ , CuGaO ₂ , CuInO _{2 and the} like can be mentioned.

The thickness of the target member 3 is not particularly limited, and is usually 3 mm to 20 mm.

<Base material>
The base material 2 has a plate shape or a cylindrical shape, and the material thereof may be a single metal such as Ti, SUS or Cu, or an alloy thereof. However, it is not limited to these.
Further, the thickness of the base material 2 is not particularly limited.

When the target member 3 and the base material 2 have a plate shape, a plurality of target members 3 are arranged on the plate-shaped base material 2 at intervals in the front-rear and left-right directions, and the target member 3 and the base material 2 are joined by a bonding material. It is usually joined.
When the target member 3 and the base material 2 have a cylindrical shape, a plurality of cylindrical target members 3 are arranged at appropriate intervals in the columnar axial direction of the cylindrical base material 2, and the target member 3 and the base material 2 are arranged. It is usual to join the material 2 with a joining material.

<Joint material>
The base material 2 and the target member 3, and the base material 2 and the gap arranging member 1 can be joined to each other by the joining material 5.
The bonding material 5 is not particularly limited as long as it can be used for bonding the target member 3 of this type and the base material 2. For example, a solder metal or a solder alloy such as In metal, In—Sn metal, or In alloy metal obtained by adding a trace metal component to In can be mentioned.

<Manufacturing of sputtering target>
First, a plurality of main gap arranging members 1 are arranged on the surface of the base material 2 at predetermined intervals.
Next, a plurality of target members 3 are arranged on the surface side of the gap arrangement member 1 with a gap 4 provided between the

adjacent target members

3 and 3. At this time, the gap arranging member 1 is arranged along the gap 4 so as to be interposed between the target member 3 and the base material 2. Then, the gap arrangement member 1, the base material 2, and the target member 3 may be joined by using solder.
However, the method is not limited to this method.

<Explanation of words>
When expressed as "X to Y" (X and Y are arbitrary numbers) in the present specification, unless otherwise specified, they mean "X or more and Y or less" and "preferably larger than X" or "preferably Y". It also includes the meaning of "smaller".
Further, when expressed as "X or more" (X is an arbitrary number) or "Y or less" (Y is an arbitrary number), it means "preferably larger than X" or "preferably less than Y". Including intention.
Further, when expressed as "X ≦" (X is an arbitrary number) or "Y ≧" (Y is an arbitrary number), it means that "X <preferably" or "Y> is preferable". Also includes the intention of.

Hereinafter, the present invention will be described based on examples. However, the present invention is not limited to the examples described here.

<Example 1>
A copper plate (back surface layer) having a thickness of 0.3 mm and a length × width of 200 mm × 20 mm and exhibiting a rectangular shape in a top view is prepared, and an intermediate layer is formed by spraying _{ZrO 2} _{on the surface of the copper plate, and further, Al 2} to form a surface layer of O ₃ spraying to the surface layer (thickness 100 [mu] m) / an intermediate layer (thickness 100 [mu] m) / back surface layer of the three-layer structure consisting of (thickness 0.3 mm) gap locating member (sample) Made.
The coefficient of linear expansion of copper (Cu) constituting the back surface layer is 17 × 10 ^-6 / K, and the coefficient of linear expansion of _{ZrO 2} ^{constituting the intermediate layer is 11 × 10 -6} / K. The coefficient of linear expansion of _{Al 2} O ₃ constituting the above ^{is 7 × 10 -6} / K.

<Example 2>
In Example 1, the surface layer (thickness 100 μm) / intermediate layer (thickness 100 μm) was the same as in Example 1, except that Y ₂ O ₃ _{was sprayed instead of Al 2} O _{3 to form a surface layer.} / A gap arrangement member (sample) having a three-layer structure composed of a back surface layer (thickness 0.3 mm) was prepared.
The coefficient of linear expansion of _{Y 2} O ₃ constituting the surface layer ^{is 7 × 10 -6} / K.

<Example 3>
In Example 1, an intermediate layer was formed by spraying MgO in place of ZrO _2, further except for forming a surface layer by thermal spraying of ZrO ₂ instead of _Al 2 _{O 3,} similarly as in Example 1 In addition, a gap arrangement member (sample) having a three-layer structure composed of a front surface layer (thickness 100 μm) / an intermediate layer (thickness 100 μm) / a back surface layer (thickness 0.3 mm) was produced.
The coefficient of linear expansion of MgO constituting the intermediate layer is 13 × 10 ^-6 / K.

<Example 4>
In Example 2, the surface layer (thickness 100 μm) / intermediate layer (thickness 100 μm) / A gap arrangement member (sample) having a three-layer structure composed of a back surface layer (thickness 0.3 mm) was produced.
The coefficient of linear expansion of Ni constituting the back surface layer is 13 × 10 ^-6 / K.

<Example 5>
In Example 3, the surface layer (thickness 100 μm) / intermediate layer (thickness 100 μm) / as in Example 3 except that the copper (Cu) constituting the back surface layer was changed to nickel (Ni). A gap arrangement member (sample) having a three-layer structure composed of a back surface layer (thickness 0.3 mm) was produced.
The coefficient of linear expansion of Ni constituting the back surface layer is 13 × 10 ^-6 / K.

<Example 6>
A titanium plate (back surface layer) having a thickness of 0.3 mm and a length × width of 200 mm × 20 mm and exhibiting a rectangular shape in a top view was prepared, and an intermediate layer was formed by spraying _{Al 2} O _{3 on the surface of the titanium plate.} Further, a gap arrangement member (sample) having a three-layer structure composed of a surface layer (thickness 100 μm) / intermediate layer (thickness 100 μm) / back surface layer (thickness 0.3 mm) by spraying mullite to form a surface layer. Was produced.
The coefficient of linear expansion of titanium (Ti) constituting the back surface layer is 9 × 10 ^-6 / K, and the coefficient of linear expansion of _{Al 2} O ₃ ^{constituting the intermediate layer is 7 × 10 -6} / K. linear expansion coefficient of mullite _{_{_{(3Al 2 O 3 · 2SiO 2}}} ) constituting the surface layer is 5 × 10 ^-6 / K.

<Comparative example 1>
A gap arrangement member having a two-layer structure composed of a front surface layer (thickness 100 μm) / back surface layer (thickness 0.3 mm), as in the first embodiment, except that the intermediate layer was not formed in the first embodiment. Sample) was prepared.

<Peeling evaluation test>
In accordance with JIS Z 0237: 2009, the gap arrangement member (sample) obtained in Examples / Comparative Examples is heated to a product temperature of 200 ° C. using an electric furnace, cooled to 25 ° C., and peeled below. The test was carried out.
In the peel test, a gap arrangement member (sample) is set on a jig, and an adhesive tape (Cellotape (registered trademark) CT-18 manufactured by Nichiban Co., Ltd.) is attached to the surface of the jig, and the angle is 300 mm / min at a 90 ° angle. The state when the adhesive tape was peeled off at a high speed was evaluated according to the following criteria.
A (very good): The peeled area was 0%.
B (good): The peeled area was less than 10%.
C (poor): The peeled area was 10% or more.

Based on the above Examples / Comparative Examples and many test results conducted by the present inventor so far, the coefficient of linear expansion of the material constituting the intermediate layer, the coefficient of linear expansion of the material constituting the front surface layer, and the back surface layer are configured. It was found that by adjusting the material so that it is within the range of the coefficient of linear expansion, the difference in the coefficient of linear expansion between the layers becomes small, and it is possible to prevent delamination from occurring due to heating.
In paragraphs [0039] to [0044] of Patent Document 2 (WO2012 / 063524), the protective member (corresponding to the gap arrangement member of the present invention) is the target member (size 210 mm × 355 mm, thickness 6 mm, coefficient of linear expansion). The substrate is sputtered in the gap between adjacent target members by interposing between the substrate (thickness 30 mm, coefficient of linear expansion 17 × 10 ^-6 / K) and the substrate (5 × 10 ^{-6 / K).} It has been confirmed that can be prevented. Since the present invention is an improvement of the protective member disclosed in Patent Document 2 (WO2012 / 063524), it is described in paragraphs [0039] to [0044] of Patent Document 2 (WO2012 / 063524). The test contents and test results are incorporated herein by reference as reference tests.

1 Gap placement member

1A Front layer

1B Intermediate layer 1C Back surface layer 2 Base material 3 Target member 4 Gap 5 Joint material

Claims

When a plurality of target members are arranged on the surface side of a base material (simply referred to as "base material") of a sputtering target, they are interposed between the target member and the base material along a gap between adjacent target members. It is a gap arrangement member,
It has a multi-layered structure in which three or more layers are laminated in the thickness direction, and is intermediate between the layer on the target member side (also referred to as "front surface layer") and the layer on the base material side (also referred to as "back surface layer"). The coefficient of linear expansion of the material provided with the layer and constituting the intermediate layer is within a range between the coefficient of linear expansion of the material constituting the front surface layer and the coefficient of linear expansion of the material constituting the back surface layer. A gap arrangement member characterized by.
The first protective layer (front surface layer), the second protective layer (intermediate layer), and the third protective layer (back surface layer) are laminated in this order from the target member toward the base material side, and the line of the material constituting each layer is formed. The gap arrangement member according to claim 1, wherein the expansion coefficient is the first protective layer ≤ the second protective layer ≤ the third protective layer.
The first protective layer (front surface layer), the second protective layer (intermediate layer), and the third protective layer (back surface layer) are laminated in this order from the target member toward the base material side, and the line of the material constituting each layer is formed. The gap arrangement member according to claim 1, wherein the expansion coefficient is a first protective layer <a second protective layer <a third protective layer.
The gap arrangement member according to any one of claims 1 to 3, wherein the thickness of the back surface layer is the same as or larger than the thickness of the front surface layer.
The first protective layer (front surface layer), the second protective layer (intermediate layer), and the third protective layer (back surface layer) are laminated in this order from the target member toward the base material side, and the thickness of each layer is the first. The gap arrangement member according to any one of claims 1 to 4, wherein 1 protective layer ≤ 2nd protective layer ≤ 3rd protective layer.
The gap arrangement member according to any one of claims 1 to 5, wherein the thickness of the surface layer is 0.2 to 20% of the thickness of the target member.
The surface layer is made of a metal material, a ceramic material, a polymer material, or a composite material of two or more of these, which constitute a target member.
The back surface layer is made of a metal material, a ceramic material, or a composite material thereof.
The gap arrangement member according to any one of claims 1 to 6, wherein the intermediate layer is made of a metal material, a ceramic material, a polymer material, or a composite material of two or more kinds thereof.
A sputtering target including a base material, a plurality of target members arranged on the surface side of the base material, and a gap arrangement member according to any one of claims 1 to 7.