JP6861035B2 - Manufacturing method of cylindrical sputtering target - Google Patents

Description

The present invention relates to a method for manufacturing a cylindrical sputtering target used in a magnetron type rotary cathode sputtering apparatus or the like.

As a magnetron type cathode sputtering apparatus, there is a magnetron sputtering apparatus provided with a cylindrical sputtering target. This magnetron sputtering apparatus has a magnetic field generator inside a backing tube that supports a cylindrical sputtering target material, and performs sputtering while rotating the target while cooling the target by flowing cooling water.

The cylindrical sputtering target of this form can obtain a target usage efficiency (60% or more) significantly higher than the target usage efficiency (20 to 30%) in the flat plate magnetron sputtering apparatus. Further, by rotating the target, a larger power can be applied per unit area as compared with the conventional flat plate magnetron sputtering apparatus, and a high film forming speed can be obtained, so that it is expected to be widely used in the future.

The structure of the cylindrical sputtering target is such that one or more target materials are joined to the backing tube. There are various joining methods such as fixing with carbon felt or a coaxial spring or filling with an elastomer. In general, a bonding method using a metal or a metal alloy having a low melting temperature, which is also called a metal solder and has conductive and heat conductive properties, is widely used. For the function of the backing tube, a material having good support of the target material, power transmission, mechanical strength, heat transfer to the cooling water, etc. is selected.

A cylindrical sputtering target composed of these members is required to have a good bonding ratio and bonding strength of each member. If these are scarce, during sputtering, two cylindrical objects, a target material with different coefficients of thermal expansion and a backing tube, are combined and the gap is fixed with a bonding material. Internal stress is generated due to the difference in the amount of volume shrinkage, and problems such as peeling of the joint or cracking of the target material are likely to occur. Further, if the bonding ratio and the bonding strength are insufficient, the cooling efficiency of the target material during sputtering is lowered, and the target material may be cracked.

Therefore, in the process of joining the target material and the backing tube, in order to improve the adhesion with the metal solder material, the same substance as the metal solder material is thinly applied to the outer surface of the backing tube and the inner surface of the target material in advance. Is being grounded. In addition, inspection of the joint state is indispensable, and observation by ultrasonic flaw detection method has become common. If a satisfactory filling or joining state cannot be obtained, it is necessary to peel off the target material after joining from the backing tube and join again.

Regarding the method for manufacturing a cylindrical sputtering target using metal solder, for example, in Patent Document 1 and Patent Document 2, the backing tube and the target material are arranged concentrically and vertically, and the metal solder melted from above is placed in the generated gap. The filling method is described.

Further, Patent Document 3 describes a method of filling molten metal solder from below by hydraulic head pressure, and Patent Document 4 floats a powder substance having a low specific gravity on the liquid surface of the solder material. A method of injecting a solder material while vibrating is described.

Japanese Unexamined Patent Publication No. 08-060351 Japanese Unexamined Patent Publication No. 2011-084795 Japanese Unexamined Patent Publication No. 2010-070842 Japanese Unexamined Patent Publication No. 2012-177156

The inventions according to Patent Documents 1 to 3 are filling methods from one direction, and in order to obtain good bondability, it is necessary to fill up to the other end, and molten solder is poured into the filling method. In some cases, it is necessary to heat the pre-treated target material and backing tube above the melting point of the metal solder. Therefore, in the methods according to Patent Documents 1 to 3, an oxide film is formed on the surface of the metal solder base-treated by heating in the latter half of the filling, which tends to cause deterioration of bondability. This becomes more remarkable as the total length of the cylindrical target is longer.

Further, as a method of removing the oxide film on the surface treated surface generated when the target material and the backing tube are heated, a method of inserting a plate-shaped or rod-shaped jig into the gap space and stirring the solution is described in Patent Document 4. There is also a method in which a powder material having a low specific gravity is floated on the liquid surface of a certain solder material and the solder material is injected while vibrating, but the work depends on the length of the cylindrical target and is not efficient.

Therefore, the present invention has been proposed in view of such conventional circumstances, and among cylindrical sputtering targets using metal solder as a bonding material, the adhesive strength and bonding ratio between the backing tube and the target material are high. It is an object of the present invention to provide an efficient method for manufacturing a cylindrical sputtering target having a high yield in the step of joining a backing tube and a target material.

The present inventors have made extensive studies on a method for manufacturing a cylindrical sputtering target, fill the gap between the target material and the backing tube with a solid bonding material, and then heat from the outside to a temperature higher than the melting point to cool and solidify. Therefore, it was found that by obtaining a good bonding state, it becomes possible to manufacture a cylindrical sputtering target that is efficient and has a high yield.

That is, one aspect of the present invention is a method for manufacturing a cylindrical sputtering target in which a cylindrical target material is bonded to an outer peripheral surface of a cylindrical backing tube via a bonding layer, the inner peripheral surface of the target material and the inner peripheral surface of the target material. A coating step of applying a bonding material to each of the outer peripheral surfaces of the backing tube, an arrangement step of arranging the backing tube coaxially in a hollow portion on the inner peripheral surface side of the target material, and an inner peripheral surface of the target material. By filling the gap between the backing tube and the outer peripheral surface of the backing tube with a solid bonding material and heating the solid bonding material to a temperature equal to or higher than the melting point and then cooling the target material and the backing tube. possess a bonding step of bonding, in the disposing step, disposing an inner diameter equal to the cylindrical jig of the target material to the upper end of the target material.

In this way, by filling the gap between the target material and the backing tube with the solid bonding material and heating and melting it, the contact area between the base treatment surface and the atmosphere is reduced, and the base treatment of the target material and the backing tube is performed. The generation of an oxide film on the surface can be suppressed. Further, after that, by cooling and solidifying, a good bonding state can be obtained, so that an efficient and high-yield cylindrical sputtering target can be manufactured.

At this time, in one aspect of the present invention, the solid bonding material can be a spherical metal solder whose diameter is equal to or less than the width of the gap.

By using spherical metal solder as the solid bonding material, it becomes easy to fill the gap between the target material and the backing tube with the bonding material.

At this time, in one aspect of the present invention, two or more types of spherical metal solders having different diameters may be used.

By using two or more types of spherical metal solders having different diameters, it is possible to reduce the voids between the metal solders at the time of filling and obtain a high filling rate.

Further, at this time, in one aspect of the present invention, at least a spherical metal solder having a diameter of 15% or more and 25% or less of the width of the gap and a spherical metal solder having a diameter of 75% or more and 85% or less of the width of the gap. May be used.

By using the large size spherical metal solder and the small size spherical metal solder together, the metal solder can be efficiently filled in the gap with a high filling rate.

Further, in one aspect of the present invention, in the arrangement step, a cylindrical jig equal to the inner diameter of the target material may be arranged at the upper end of the target material.

It is preferable to arrange a cylindrical jig at the upper end of the target material in consideration of volume reduction when the filled joint material is melted and from the viewpoint of facilitating filling of the joint material in the gap.

Further, in one aspect of the present invention, the material of the bonding material may be indium or an alloy containing the same as a main component.

Indium or an alloy containing this as a main component is preferable as a bonding material because it has excellent thermal conductivity.

According to the present invention, the adhesive strength and the bonding ratio between the backing tube and the target material can be increased, and in the step of bonding the backing tube and the target material, an efficient and high-yield cylindrical sputtering target can be manufactured. be able to.

It is schematic cross-sectional view which cut the cylindrical sputtering target which concerns on one Embodiment of this invention in the plane including the central axis. It is a process drawing which shows the outline of the process in the manufacturing method of the cylindrical sputtering target which concerns on one Embodiment of this invention. FIG. 5 is a schematic cross-sectional view showing a state in which a solid bonding material is filled in a filling step in the method for manufacturing a cylindrical sputtering target according to an embodiment of the present invention. FIG. 5 is a schematic cross-sectional view showing a state in which a solid bonding material is melted by heating and then cooled in a bonding step in the method for manufacturing a cylindrical sputtering target according to an embodiment of the present invention, and the target material and the backing tube are bonded.

Hereinafter, a method for manufacturing a cylindrical sputtering target according to the present invention will be described in the following order with reference to the drawings. The present invention is not limited to the following examples, and can be arbitrarily modified without departing from the gist of the present invention.
1. 1. Overview of cylindrical sputtering target 2. Manufacturing method of cylindrical sputtering target 2-1. Coating process 2-2. Placement process 2-3. Filling process 2-4. Joining process

<1. Overview of Cylindrical Sputtering Targets>
First, an outline of the cylindrical sputtering target according to the present invention will be described. FIG. 1 is a schematic cross-sectional view of a cylindrical sputtering target according to an embodiment of the present invention cut along a plane including a central axis. As shown in FIG. 1, in the cylindrical sputtering target 10 according to the present invention, the target material 11 is installed on the outer peripheral portion of the backing tube 12, and the target material 11 and the backing tube 12 are connected via a bonding layer 13. Is joined. More specifically, in the cylindrical sputtering target 10, the backing tubes 12 are coaxially arranged in the hollow portion of the target material 11, and the backing tubes 12 are joined in a state where their central axes are aligned.

The size of the cylindrical sputtering target 10 can be appropriately adjusted according to the material, the demand of the consumer, and the like, and is not particularly limited. For example, when a cylindrical ceramic sintered body having an outer diameter of 100 mm to 200 mm, an inner diameter of 80 mm to 180 mm, and a total length of 50 mm to 200 mm is used as the target material 11, when the target material 11 is used alone, it is divided. The size of the cylindrical sputtering target 10 is appropriately determined depending on the situation.

The material of the cylindrical ceramics sintered body that can be used as the cylindrical target material 11 can be appropriately selected depending on the application, and is not particularly limited. For example, oxidation containing at least one main component selected from indium (In), tin (Sn), zinc (Zn), aluminum (Al), niobium (Nb), tantalum (Ta), and titanium (Ti). A cylindrical ceramic sintered body composed of an object or the like can be used.

For example, a cylindrical ceramics sintered body containing indium oxide as a main component, which is easily compatible with the bonding material 13 described later, specifically, indium oxide (ITO) containing tin and indium oxide (ICO) containing cerium (Ce). ), Indium oxide (IGO) containing gallium (Ga), indium oxide (IGZO) containing gallium and zinc, and the like, a cylindrical ceramic sintered body is preferably used as the target material 11. The target material 11 may be not only the ceramic sintered body but also a metal target material such as niobium. Since the metal target material is easy to process, it is easy to obtain the target material 11 having a long overall length.

The material of the cylindrical backing tube 12 has thermal conductivity that can ensure sufficient cooling efficiency so that the bonding material 13 does not deteriorate or melt when the cylindrical sputtering target 10 is used, and has electrical conductivity that can be discharged during sputtering. , As long as it has enough strength to support the cylindrical sputtering target 10. For example, austenitic stainless steel, titanium or titanium alloy, copper or copper alloy. In particular, it is common to use SUS304 or titanium alloy.

The total length of the backing tube 12 can be appropriately adjusted according to the size of the cylindrical sputtering target 10. The inner diameter can be appropriately adjusted according to the sputtering apparatus, and these are not particularly limited. Further, the outer diameter of the backing tube 12 is preferably set in consideration of the thickness of the base layer and the difference in the coefficient of linear expansion between the backing tube 12 and the target material 11.

The bonding material 13 fills the clearance between the target material 11 and the backing tube 12, heats above the melting point to melt, and then allows the target material 11 and the backing tube 12 to cool, thereby allowing the target material 11 and the backing tube 12 to cool. 12 are joined. The bonding material 13 needs to have characteristics such as thermal conductivity in the same manner as the backing tube 12 described above, and for example, indium and indium alloys, tin and tin alloys and the like are used. Preferably, indium and indium alloys are used.

When the bonding material 13 containing indium as a main component is used, it is possible to use a bonding material containing indium in an amount of 50% by mass or more, preferably 70% by mass to 100% by mass, and more preferably 80% by mass to 100% by mass. preferable. In particular, a low melting point bonding material containing 80% by mass or more, preferably 90% by mass to 100% by mass of indium may be used as the bonding material. Such a low melting point bonding material is soft because the bond between atoms or molecules is weak, and has excellent workability because the hardness after cooling and solidification is in an appropriate range.

<2. Manufacturing method of cylindrical sputtering target>
Next, a method for manufacturing a cylindrical sputtering target according to an embodiment of the present invention will be described. FIG. 2 is a process diagram showing an outline of a process in a method for manufacturing a cylindrical sputtering target according to an embodiment of the present invention. One embodiment of the present invention is a method for manufacturing a cylindrical sputtering target in which a cylindrical target material is joined to an outer peripheral surface of a cylindrical backing tube via a bonding layer, and is an inner peripheral surface of the target material and a backing tube. A coating step S1 in which a bonding material is applied to each of the outer peripheral surfaces of the target material, an arrangement step S2 in which a backing tube is coaxially arranged in a hollow portion on the inner peripheral surface side of the target material, and an inner peripheral surface of the target material and the backing tube. The filling step S3 for filling the gap between the outer peripheral surface with the solid bonding material and the bonding step S4 for joining the target material and the backing tube by heating the solid bonding material to a temperature equal to or higher than the melting point and then cooling the solid bonding material. Have.

In this way, by filling the gap between the target material and the backing tube with the solid bonding material and heating and melting it, the contact area between the base treatment surface and the atmosphere is reduced, and the base treatment of the target material and the backing tube is performed. The generation of an oxide film on the surface can be suppressed. The present invention has been completed based on the finding that a good bonding state can be obtained and a cylindrical sputtering target with high efficiency and high yield can be manufactured. Hereinafter, each step in the method for manufacturing a cylindrical sputtering target according to an embodiment of the present invention will be described in detail.

(2-1. Coating process)
The coating step S1 is a step of coating the bonding material on the inner peripheral surface of the target material and the outer peripheral surface of the backing tube.

[Preparation of target material and backing tube]
First, the target material 11 and the backing tube 12 are prepared. As the target material 11, the above-mentioned cylindrical ceramic sintered body is prepared. The number of sintered bodies may be one or a plurality. The backing tube 12 is also as described above. For example, a cylindrical SUS304 or titanium alloy backing tube is prepared.

[Applying metal solder]
Next, metal solder is applied to the joint surfaces of the target material 11 and the backing tube 12. The target material 11 is applied to the inner peripheral surface to be joined to the backing tube 12, and the backing tube 12 is applied to the outer peripheral surface. In order to prevent metal solder from adhering to unnecessary parts other than the joint surface, heat-resistant tape may be attached to the target material 11 and the backing tube 12 for masking.

The metal solder can be applied by a plating process, an ultrasonic soldering apparatus, or the like. The method of using an ultrasonic soldering apparatus is preferable because it has good wettability with the bonding material and is easy to work with. In the method of applying metal solder with an ultrasonic soldering device, in order to perform it efficiently, the fluidity of the bonding material is increased by setting the iron tip and backing tube to a temperature higher than the melting point of the bonding material, and application while stretching is performed. Is possible. Further, by forming the iron tip in close contact with the outer circumference of the backing tube 12 and the inner circumference of the target material 11, a uniform treated surface can be obtained. The thickness of the metal solder at this time is preferably 10 to 30 μm.

(2-2. Placement process)
The arrangement step S2 is a step of coaxially arranging the backing tube 12 in the hollow portion on the inner peripheral surface side of the target material 11. FIG. 3 is a schematic cross-sectional view showing a state in which a solid bonding material is filled in a filling step described later in the method for manufacturing a cylindrical sputtering target according to an embodiment of the present invention. The arrangement of the backing tube will be described.

[Arrangement]
The backing tube 22 is installed by fixing one end to a pedestal or the like. For example, it may be fixed to a heat-resistant resin plate 24 having a hole having the same diameter as the backing tube 22 outer diameter. The end of the backing tube 22 in the axial direction is sealed with a heat-resistant O-ring 25 or the like, and then the backing tube 22 is coaxially arranged in the hollow portion of the target material 21 so that the sealing side is downward. The target material 21 and the backing tube 22 are made upright.

It is important to arrange the backing tube 22 coaxially with the hollow portion of the target material 21, that is, in a state where their central axes coincide with each other, and to join the two. If the two are joined in a state where the central axes are deviated, the center of the outer diameter and the center of the inner diameter of the obtained cylindrical sputtering target 10 are deviated. As a result, the cylindrical sputtering target 10 may expand unevenly due to the heat load during sputtering, and the target material 21 may be cracked or peeled off.

Further, as will be described later, in the method for manufacturing a cylindrical sputtering target according to an embodiment of the present invention, in order to fill the solid bonding material 23, if the bonding material 23 is melted by heating after filling, the bonding material 23 is melted at the time of filling. The volume occupied by the bonding material is reduced due to the voids between the bonding materials. Therefore, a cylindrical jig 26 having the same inner diameter as the target material 21 is placed on the upper end of the target material 21 so that the joining material 23 can be filled in a larger amount in consideration of the volume reduction, and the upper end of the backing tube 22 is outside. It is preferable to place a cylindrical jig having the same diameter (hereinafter, the cylindrical jig arranged on the backing tube 22 is referred to as a dummy tube 27) and fix it with heat-resistant tape, for example.

If the backing tube 22 has a sufficient length with respect to the target material 21, the cylindrical jig 26 may be arranged only at the upper end of the target material 21. Further, the upper portion 261 of the cylindrical jig 26 may have a shape that expands upward in order to facilitate filling with the spherical metal solder 23. The material of the cylindrical jig 26 and the dummy tube 27 is preferably made of stainless steel because it is used repeatedly.

(2-3. Filling process)
The filling step S3 is a step of filling the gap between the inner peripheral surface of the target material 21 and the outer peripheral surface of the backing tube 22 with a solid bonding material.

[filling]
In the filling step S3, the gap between the backing tube 22 and the target material 21 created in the arranging step S2 is filled with the solid bonding material 23 from above via, for example, the above-mentioned cylindrical jig 26. The solid bonding material 23 is not particularly limited, but it is preferable to use a spherical metal solder from the viewpoint of ease of production and high filling rate. The method for producing the spherical metal solder is not particularly limited. A granulation method in oil, a uniform droplet spraying method, or a method having a small diameter may be manufactured by a centrifugal spraying method or the like.

The higher the filling rate of the spherical metal solder 23 in the gap space created by the arrangement of the target material 21 and the backing tube 22, the larger the contact area between the spherical metal solder 23 and the base treatment surface of the target material 21 or the backing tube 22. To increase. Therefore, as compared with the case of filling the molten metal solder from the beginning, the oxide film formed on the base-treated surface during heating is relatively reduced, and the interfacial strength between the base-treated surface and the metal solder is improved.

The diameter of the spherical metal solder 23 needs to be equal to or less than the width of the gap between the target material 21 and the backing tube 22. Further, as the spherical metal solder 23, one having a diameter of 0.2 mm or more is preferably used because of its ease of manufacture and availability. However, the spherical metal solder 23 is not limited to this, and for example, a powdery metal solder having a small diameter (average particle size) (for example, on the order of μm) may be used.

The spherical metal solder 23 may be filled with one type or two or more types having different diameters. In order to obtain a high filling rate, it is important to use spherical metal solders 23A and 23B having several diameters in combination, preferably a spherical metal having a small particle size having a diameter of 15 to 25% with respect to the gap length. It is preferable to use the solder 23B and the spherical metal solder 23A having a large particle size of 75 to 85% in diameter. Further, in the filling method, first, a large-sized spherical metal solder 23A is filled, vibration is applied by a mechanical vibration source such as a small vibrator, and then the small-sized spherical metal solder 23B is filled. The method gives a high filling rate. As a method of applying vibration for efficient filling, for example, it is preferable to bring a mechanical vibration source such as a small vibrator into contact with the outer peripheral surface of the target material 21 and move it in the longitudinal direction of the target material to apply vibration.

Immediately after filling, a space is created due to the spherical metal solder 23. However, when the target material 21 is heated from the outside and melted, the filling height is lower than the height at the time of filling. Therefore, the filling height is the target material 21 at the time of melting. Adjust so that it is at the top of. In addition, the positions of the upper surfaces of the cylindrical jig 26 and the dummy tube 27 to be installed on the target material 21 are set higher than the height immediately after filling.

(2-4. Joining process)
The joining step S4 is a step of joining the target material 21 and the backing tube 22 by heating the joining material 23 filled in the filling step S3 to a melting point or higher and then cooling it. FIG. 4 is a schematic cross section showing a state in which a solid bonding material is melted by heating and then cooled in a bonding step in the method for manufacturing a cylindrical sputtering target according to an embodiment of the present invention, and the target material and the backing tube are bonded. It is a figure.

[Joining]
In the joining step S4, the spherical metal solder 23 is filled in the gap between the backing tube 32 and the target material 31, and then heated to melt and join the spherical metal solder 23. The heating heats the outer peripheral surface of the target material 31. The heating method is not particularly limited, but it is easy to install and remove by using a band heater or the like. The heating temperature is set to a temperature higher than the melting point of the bonding material 33.

By heating, the spherical metal solder 23 filled in the gap between the backing tube 32 and the target material 31 is melted and joined at the same time as the base treatment surface on the outer circumference of the backing tube 32 and the inner circumference of the target material 31. On the other hand, as in Patent Documents 1 and 2, when the solder of the solution is poured from above after heating, it is joined from the lower side, so that an oxide film is likely to be formed on the surface treated surface due to heating. It reduces the bondability. In the method for manufacturing a cylindrical sputtering target according to the present invention, since the bonding is performed at the same time as heating, this can be prevented. Further, in the method for manufacturing a cylindrical sputtering target according to the present invention, since the solid bonding material 23 is filled and then melted, it is possible to prevent the mixing of air bubbles as compared with the case where the solder of the solution is poured from above. ..

[cooling]
After that, the heating of the band heater is stopped and the band heater is cooled as it is. Finally, it is cooled and solidified, the cylindrical jig 36 and the dummy tube 37 are removed, and the heat-resistant tape attached to the surface of the target material 31 for masking use is peeled off to obtain a cylindrical sputtering target. The inner peripheral surface of the cylindrical jig 36 and the outer peripheral surface of the dummy tube 37 are not coated with metal solder to improve the wettability of the bonding material, so that the cylindrical jig 36 and the dummy tube 37 are not coated. The adhesion between the solder and the bonding material 33 is weak and can be easily removed.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

In the following Examples and Comparative Examples, the bonding ratio between the target material and the backing tube in the ultrasonic flaw detector is determined by using the ultrasonic flaw detector (KJTD Co., Ltd., SDS-WIN) in Examples 1 to 6. , The evaluation was performed using the cylindrical sputtering targets of Comparative Examples 1 to 3 as a sample. The joining ratio is obtained by the ratio of the joining defective part area to the joining area. The evaluation of the bonding strength between the target material and the bonding layer is performed by forming a gap space with a flat plate material of 90 mm × 150 mm as an alternative to the cylindrical sputtering target, bonding under the same conditions, and using this as a test piece for a tensile test device. Evaluation was made by measuring the joint strength using (Autograph, manufactured by Shimadzu Corporation).

(Comparative Example 1)
In Comparative Example 1, two ITO-made cylindrical ceramic sintered bodies having an outer diameter of 153 mm, an inner diameter of 135 mm, and a total length of 165 mm were prepared. All cylindrical ceramic sintered bodies were masked with polyimide tape in order to prevent excess bonding material from adhering to parts other than the inner peripheral surface, which is the bonding surface. After that, the inner peripheral surface to be the joint surface was processed into Sunbonder USM-528 manufactured by Kuroda Techno Co., Ltd. (ultrasonic striking terminal, shape 50 x 10 mm, and the surface in contact with the target material was processed to have the same radius of curvature as the inner surface of the target material. (Used) was used, and indium was used as the solder material to obtain a target material.

One backing tube made of stainless steel, having a length of 370 mm, an outer diameter of 133 mm, and an inner diameter of 125 mm was prepared. The outer peripheral surface to be the joint surface was grounded in the same manner as described above. The backing tube and the target material are arranged vertically using a ring-shaped plate (made of PEEK) so as to be coaxial with the hollow part, and the lower end is sealed with a ring-shaped rubber (made of silicone). A ring-shaped rubber (made of silicone) was inserted into the gap. A funnel-shaped jig (made of aluminum) was installed at the upper end of the target material.

Next, at the same time as heating the outer peripheral portion of the target material, the funnel-shaped jig was filled with metal solder to heat the outer peripheral portion of the cylindrical jig. As the metal solder, indium of a cold rolled plate (thickness 5 mm) was used. As a result, the metal solder was melted and flowed into the gap space created by the arrangement of the backing tube and the target material, and it was confirmed that the solder was filled, and then cooled and solidified to obtain a cylindrical ITO sputtering target.

Finally, the bonding ratio and adhesive strength of this ITO cylindrical sputtering target were measured. The results are shown in Table 1.

(Comparative Example 2)
In Comparative Example 2, one niobium cylindrical target material having an outer diameter of 153 mm, an inner diameter of 135 mm, and a total length of 330 mm was prepared. Using a stainless steel backing tube of the same size as in Comparative Example 1, the base treatment was performed in the same manner as in Comparative Example 1. Similarly, the target material, the backing tube, the ring-shaped heat-resistant resin plate, the ring-shaped rubber, the funnel-shaped jig, and the metal solder were arranged. Since there is only one target material, the ring-shaped rubber (made of silicone) in the gap between the target materials was not used. A niobium cylindrical sputtering target was obtained under the same conditions and methods as in Comparative Example 1 and evaluated. The results are shown in Table 1.

(Comparative Example 3)
In Comparative Example 3, two ITO-made cylindrical ceramic sintered bodies having an outer diameter of 153 mm, an inner diameter of 136 mm, and a total length of 165 mm were prepared. Further, the same backing tube as in Comparative Example 1 was prepared, and the base treatment was performed by the same method as in Comparative Example 1. Then, the target material, the backing tube, the ring-shaped heat-resistant resin plate, the ring-shaped rubber, the funnel-shaped jig, and the metal solder are arranged in the same manner as in Comparative Example 1, and the ITO cylindrical sputtering target is arranged under the same conditions and methods as in Comparative Example 1. Was obtained and evaluated. The results are shown in Table 1.

(Example 1)
In Example 1, an ITO target material and a stainless steel backing tube having the same size as in Comparative Example 1 were used, and the base treatment was performed by the same method.

In the first embodiment, the backing tube and the target material are arranged vertically so as to be coaxial with the hollow portion, the lower end portion is sealed with a ring-shaped heat-resistant resin plate and a ring-shaped rubber, and the gap between the target materials is filled. A ring-shaped rubber was inserted. A dummy tube with the same inner and outer diameter and length of 165 mm as the backing tube is placed on the upper end of the backing tube, and a cylindrical jig with the same inner and outer diameter and length of 165 mm as the target material is placed on the upper end of the target material and fixed with heat resistant tape. And made it a dummy part. Indium having a diameter of 0.2 mm and a diameter of 0.8 mm was used for the spherical metal solder.

First, fill the gap created by the placement of the backing tube and the target material with a spherical metal solder of φ0.8 mm, and use a handheld vibrator (Slive MD-7300 manufactured by Daito Denki Kogyo Co., Ltd.) to evenly cover the outer circumference of the target material. It was vibrated and subsequently filled with a φ0.2 mm spherical metal solder in the same manner. The filling height was about 5 mm lower than the upper end of the cylindrical jig.

Next, the outer peripheral portion of the target was heated to confirm that all the filled spherical metal solder had melted, cooled and solidified, the cylindrical jigs were removed, unnecessary bonding layers were removed, and a cylindrical ITO sputtering target was obtained. It was. Finally, the bonding ratio and adhesive strength of this ITO cylindrical sputtering target were measured. The results are shown in Table 1.

(Example 2)
In Example 2, a target material and a backing tube having the same size and material as in Comparative Example 2 were prepared, and the base treatment was performed by the same method. Further, the target material, the backing tube, the ring-shaped heat-resistant resin plate, the ring-shaped rubber, the cylindrical jig, and the like were arranged in the same manner as in Example 1. Since there is only one target material, the ring-shaped rubber (made of silicone) in the gap between the target materials was not used. A niobium cylindrical sputtering target was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 1.

(Example 3)
In Example 3, a target material and a backing tube having the same size and material as in Comparative Example 3 were prepared, and the base treatment was performed by the same method. Further, the target material, the backing tube, the ring-shaped heat-resistant resin plate, the ring-shaped rubber, the cylindrical jig, and the like were arranged in the same manner as in Example 1. Hereinafter, an ITO cylindrical sputtering target was prepared and evaluated in the same manner as in Example 1. Indium having a diameter of 0.3 mm and a diameter of 1.2 mm was used as the spherical metal solder at this time. The results are shown in Table 1.

(Example 4)
In Example 4, a target material and a backing tube having the same size and material as in Example 1 were prepared, and the base treatment was performed by the same method. Further, the target material, the backing tube, the ring-shaped heat-resistant resin plate, the ring-shaped rubber, the cylindrical jig, and the like were arranged in the same manner as in Example 1. As the spherical metal solder at this time, only one type having a diameter of 0.2 mm was used. Hereinafter, an ITO cylindrical sputtering target was obtained and evaluated under the same conditions and methods as in Example 1. The results are shown in Table 1.

(Example 5)
In Example 5, a target material and a backing tube having the same size and material as in Example 1 were prepared, and the base treatment was performed by the same method. Further, the target material, the backing tube, the ring-shaped heat-resistant resin plate, the ring-shaped rubber, the cylindrical jig, and the like were arranged in the same manner as in Example 1. As the spherical metal solder at this time, only one type having a diameter of 0.5 mm was used. Hereinafter, an ITO cylindrical sputtering target was obtained and evaluated under the same conditions and methods as in Example 1. The results are shown in Table 1.

(Example 6)
In Example 6, a target material and a backing tube having the same size and material as in Example 1 were prepared, and the base treatment was performed by the same method. Further, the target material, the backing tube, the ring-shaped heat-resistant resin plate, the ring-shaped rubber, the cylindrical jig, and the like were arranged in the same manner as in Example 1. As the spherical metal solder at this time, only one type having a diameter of 0.8 mm was used. Hereinafter, an ITO cylindrical sputtering target was obtained and evaluated under the same conditions and methods as in Example 1. The results are shown in Table 1.

From Table 1, in the cylindrical sputtering targets according to Examples 1 to 6 in which a solid bonding material was filled and then bonded, the bonding rate and the bonding strength were as high as 95% or more and 5.5 MPa or more. was gotten. In particular, in the cylindrical sputtering targets according to Examples 1 to 3 using two types of metal solders having a large particle size and a small particle size, the bonding ratio is 99% or more and the bonding strength is 6.2 MPa or more, which is the highest. The bonding ratio and bonding strength were obtained. On the other hand, when molten metal solder is filled and joined as in Comparative Examples 1 to 3, the joining ratio is about 85% and the joining strength is less than 4.0 MPa, which is a sufficient joining ratio and joining strength. Could not be obtained. As in the present invention, by filling the gap between the target material and the backing tube with a solid bonding material and heating and melting it, the contact area between the surface to be treated and the atmosphere is reduced, and the target material and the backing tube are separated from each other. It is considered that a cylindrical sputtering target having a good bonding state can be obtained because the generation of an oxide film on the surface to be treated can be suppressed and the mixing of air bubbles can be prevented.

10 Cylindrical sputtering target, 11,21,31 target material, 12,22,32 backing tube, 13,33 joint material, 23 joint material (spherical metal solder), 23A spherical metal solder (large particle size), 23B Spherical metal solder (small particle size), 24,34 heat-resistant resin plate, 25,35 heat-resistant O-ring, 26,36 cylindrical jig, 261,361 Upper part of cylindrical jig

Claims (5)

A method for manufacturing a cylindrical sputtering target in which a cylindrical target material is bonded to the outer peripheral surface of a cylindrical backing tube via a bonding layer.
A coating step of applying a bonding material to each of the inner peripheral surface of the target material and the outer peripheral surface of the backing tube, and
An arrangement step of coaxially arranging the backing tube in a hollow portion on the inner peripheral surface side of the target material, and
A filling step of filling a gap between the inner peripheral surface of the target material and the outer peripheral surface of the backing tube with a solid bonding material.
Heating the bonding material of the solid above the melting point, by then it cooled, possess a bonding step of bonding the backing tube and the target material,
A method for manufacturing a cylindrical sputtering target, in which a cylindrical jig equal to the inner diameter of the target material is placed at the upper end of the target material in the placement step. The method for manufacturing a cylindrical sputtering target according to claim 1, wherein the solid bonding material is a spherical metal solder whose diameter is equal to or less than the width of the gap. The method for manufacturing a cylindrical sputtering target according to claim 2, wherein two or more types of spherical metal solders having different diameters are used. The third aspect of claim 3, wherein at least the spherical metal solder having a diameter of 15% or more and 25% or less of the width of the gap and the spherical metal solder having a diameter of 75% or more and 85% or less of the width of the gap are used. A method for manufacturing a cylindrical sputtering target. The method for producing a cylindrical sputtering target according to any one of claims 1 to 4 , wherein the material of the bonding material is indium or an alloy containing the same as a main component.

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