JP2020158806A - Method for manufacturing cylindrical sputtering target - Google Patents

Abstract

To provide a method for manufacturing a cylindrical sputtering target, capable of suppressing the influence of an oxide film to prevent poor bonding and improve a yield.SOLUTION: A method for manufacturing a cylindrical sputtering target comprises: a base treatment step of applying a base treatment bonding material to a member on at least one of the inner peripheral surface of the cylindrical target material and the outer peripheral surface of a cylindrical backing tube to form a first surface treatment layer having a thickness of 0.1 mm or more and 0.8 mm or less; and the bonding step of inserting the cylindrical backing tube into the cylindrical target material to fill a space between the cylindrical target material and the cylindrical backing tube with a molten bonding material for filling. The base treatment step includes scratching at least the surface of the first base treatment layer, and the bonding step includes heating the first surface treatment layer until at least the surface of the first surface treatment layer is in a semi-molten state to fill with the bonding material for filling.SELECTED DRAWING: Figure 3

Description

The present invention relates to a method for manufacturing a cylindrical sputtering target used in a sputtering apparatus.

A sputtering apparatus that performs sputtering while rotating a cylindrical sputtering target is known. In the cylindrical sputtering target used in this type of sputtering apparatus, as shown in Patent Document 1, the inner peripheral surface of the cylindrical target material is joined to the outer peripheral surface of the cylindrical backing tube.
In this joining, a base-treated joint material similar to or similar to the joint material is applied to the outer peripheral surface of the cylindrical backing tube to be the joint surface and the inner peripheral surface of the cylindrical target material to form a base-treated coating, and then a base-treated coating is formed. A cylindrical backing tube is inserted into the target material to provide a gap for the joint between the two, and the target material and the cylindrical backing tube are kept in a heated state, and the molten joint material is placed in the gap. A joining method of supplying and filling a gap is known. Indium (In) is often used as the bonding material.

In this case, the surface of the base treatment bonding material of the target material and the cylindrical backing tube is oxidized after cooling after the base treatment and reheating before joining to fill the gap between the two. An oxide film is formed.
The formation of an oxide film on the surface of the surface-treated bonding material hinders the contact between the bonding material to be filled and the surface-treated bonding material, and a bonding failure is likely to occur. For a cylindrical sputtering target with poor bonding, it is necessary to heat the entire surface to melt the bonding material, remove the target material from the backing tube, and perform the bonding again. On the other hand, as the size of the substrate to be sputtered increases, the target material becomes longer, and from the viewpoint of improving production efficiency, there is a tendency to increase the power density during sputter film formation, and improvement of bonding strength is also desired. There is.

As a countermeasure for this, for example, in Patent Document 2, after filling the gap between the cylindrical target material and the cylindrical backing tube with a bonded material in a molten state, a steel wire or a steel plate is inserted and the bonding material filled between them is inserted. Is disclosed to stir and integrate the filled bonding material and the base-treated bonding material.
In Patent Document 3, a powder substance having a lighter specific gravity than the solder material as a bonding material is put in the space between the cylindrical target material and the cylindrical backing tube, and then molten solder is injected into the space to form the powder substance. Is floated on the liquid surface of the solder material, and the powder material is injected while vibrating to physically stir the solder material.
In Patent Document 4, a solid bonding material is filled in the gap between the cylindrical target material and the cylindrical backing tube, and the bonding material is heated and melted to reduce the contact area between the surface to be treated and the atmosphere. , The generation of oxide film on the base treatment surface of the target material and the cylindrical backing tube is suppressed.

Japanese Unexamined Patent Publication No. 2014-37619 Japanese Patent No. 6341146 Japanese Unexamined Patent Publication No. 2012-177156 Japanese Unexamined Patent Publication No. 2018-11168

However, in the case of Patent Document 2, it takes time and effort to stir the bonding material. Moreover, in order to remove the oxide film of the applied bonding material over the entire surface, it is necessary to stir the entire gap between the target material and the backing tube, and bonding failure may occur in a portion where the stirring is insufficient. Is high.
The same applies to Patent Document 3, and a vibration source for vibrating the powder material is required as another device, and if the solder material is not sufficiently agitated by the vibration of the powder material, it may lead to poor bonding. There is.
In the manufacturing method of Patent Document 4, if an oxide film adheres to the outer peripheral surface of the solid bonding material and the inner and outer peripheral surfaces of the target material and the backing tube before the bonding, it becomes difficult to avoid the bonding failure. Therefore, before arranging the target material in the backing tube, it is necessary to remove the oxide film formed on the surface of the bonding material, the target material, and the inner and outer peripheral surfaces of the backing tube.

In view of such circumstances, it is an object of the present invention to suppress the influence of the oxide film, prevent the occurrence of bonding defects, and improve the yield.

In the method for manufacturing a cylindrical sputtering target of the present invention, a gap between the inner peripheral surface of the cylindrical target material and the outer peripheral surface of the cylindrical backing tube inserted inside the cylindrical target material is filled with a joining material and joined. A method for manufacturing a cylindrical sputtering target, in which a base treatment bonding material is applied to at least one of the inner peripheral surface of the cylindrical target material and the outer peripheral surface of the cylindrical backing tube to 0.1 mm or more. After the base treatment step of forming the first base treatment layer of 0.8 mm or less and the base treatment step, the cylindrical backing tube is inserted into the cylindrical target material, and the cylindrical target material and the cylindrical backing are inserted. It has a joining step of filling a gap between the tube and a filling bonding material in a molten state, and in the base treatment step, at least the surface of the first base treatment layer is scratched, and in the joining step, the said After heating until at least the surface of the first base treatment layer is in a semi-molten state, the filling bonding material is filled.

The surface of the first base treatment layer formed in the base treatment step may be oxidized during cooling after application of the base treatment bonding material and during reheating during the bonding step to form an oxide film. On the other hand, since the first base treatment layer is formed thick, the surface of the first base treatment layer is at least semi-molten during the joining step, so that the surface is in a hanging state. At this time, even if the oxide film is formed on the surface by scratching the surface of the first base treatment layer in advance, when the surface portion hangs down, the oxide film hangs down while being destroyed at the scratched portion. Is divided. By filling the filled state bonding material in a molten state with the surface hanging down, the molten state filling bonding material is mixed while entering the surface portion of the first base treatment layer in which the oxide film is divided. .. In addition, a part of the oxide film is washed away from the gap by filling the filling bonding material. Even if a part of the oxide film remains in the gap, it is divided, so that the base treatment bonding material and the new filling bonding material can be integrated to form a strong bonding layer.
Since the first base treatment layer is in a hanging state over the entire circumference, the oxide film can be divided over the entire circumference.

In this case, if the thickness of the first base treatment layer is less than 0.1 mm, the oxide film is less likely to be broken because it is less likely to hang down even in a semi-molten state. If the thickness of the first base treatment layer exceeds 0.8 mm, the base treatment process takes time, and when it hangs down due to its own weight, the wall thickness becomes too large, and a cylindrical backing tube is inserted into the cylindrical target material. It may not be possible to do so.

As one embodiment of the method for manufacturing a cylindrical sputtering target, in the base treatment step, the first base treatment layer is applied to the other member on the side opposite to the one member on which the first base treatment layer is formed. A second base treatment layer having a thickness thinner than that of the first base treatment layer is formed, and a scraping plate that can be arranged so as to project radially in the gap is provided in the circumferential direction on the one member on which the first base treatment layer is formed. In the joining step, the cylindrical backing tube is provided in the cylindrical target material while scraping at least a part of the oxide film formed on the surface of the second surface treatment layer by the scraping plate. Should be inserted.

In this manufacturing method, in addition to the thick first base treatment layer, at least a part of the oxide film is removed from the thin second base treatment layer by a scraping plate, so that the thin-walled second base treatment layer is newly filled. The bonding material and the first surface treatment layer and the second surface treatment bonding material can be bonded more firmly. Moreover, since a part of the oxide film can be removed by inserting the cylindrical backing tube into the cylindrical target material, the work is easy.

According to the present invention, it is possible to suppress the influence of the oxide film, prevent the occurrence of bonding defects, and improve the yield.

It is a vertical sectional view which shows the cylindrical sputtering target manufactured by the manufacturing method of 1st Embodiment. It is a flowchart explaining the manufacturing method of a cylindrical sputtering target. It is a vertical cross-sectional view of the cylindrical backing tube which formed the base treatment layer. It is a vertical sectional view of the cylindrical target material which formed the base treatment layer. FIG. 5 is a vertical cross-sectional view showing a state before the cylindrical backing tube is inserted into the cylindrical target material and heated in the manufacturing method of the first embodiment. It is a vertical cross-sectional view which shows the state which reheated from the state shown in FIG. It is a vertical cross-sectional view which shows the state which lowered the cylindrical backing tube from the state shown in FIG. It is a vertical cross-sectional view which shows the state before inserting the cylindrical backing tube into the cylindrical target material in the manufacturing method of 2nd Embodiment. It is a top view which shows the scraping plate. It is a vertical cross-sectional view which shows the cylindrical sputtering target manufactured by the manufacturing method of 2nd Embodiment. It is a vertical cross-sectional view which shows the state before inserting the cylindrical backing tube into the cylindrical target material in the manufacturing method of 3rd Embodiment.

Hereinafter, embodiments of a method for manufacturing a cylindrical sputtering target according to the present invention will be described with reference to the drawings.
First, the first embodiment will be described.
In the cylindrical sputtering target 1, for example, as shown in FIG. 1, a cylindrical backing tube (hereinafter referred to as a backing tube) 3 is inserted into a cylindrical target material (hereinafter referred to as a target material) 2, and these target materials are inserted. The inner peripheral surface of 2 and the outer peripheral surface of the cylindrical backing tube 3 are joined via the joint portion 4. In this case, the target material 2 and the backing tube 3 are arranged so that their central axes coincide with each other.

Since the target material 2 has a long shape, it is generally configured by connecting a plurality of divided target materials 2a divided in the length direction.

The material and dimensions of the target material 2 and the backing tube 3 are not particularly limited. For example, the target material 2 has an inner diameter made of a metal such as copper or silver, or a ceramic such as AZO which is an oxide sintered body of Al or Zn. A tubular member of 120 mm to 140 mm can be used, and the backing tube 3 uses a tubular member having an outer diameter of 119 mm to 139 mm and a length of 0.5 m to 4 m made of titanium, stainless steel, or copper or a copper alloy. Can be done. In this case, the target material 2 is arranged on the outer circumference of the cylindrical backing tube 3 in a state where a plurality of short divided target materials 2a having a length of about 30 cm are connected. With the backing tube 3 inserted in the target material 2, a gap of 0.5 mm to 1 mm is formed in the radial direction between the inner peripheral surface of the target material 2 and the outer peripheral surface of the backing tube 3, and a gap of 0.5 mm to 1 mm is formed in this gap. A rod-shaped spacer (not shown) for holding a gap may be inserted, and in this case, the target material 2 and the backing tube 3 are integrated with the rod-shaped spacer by the joint portion 4.

The joint 4 is, for example, an indium alloy having an indium content of 60% by mass or more (for example, In—Sn alloy, In—Bi alloy, In—Zn alloy) or pure indium, a tin alloy having a tin content of 60% by mass or more, or a tin alloy. Pure tin or the like is used. The joint portion 4 is composed of a base-treated joint material applied to the target material 2 and the backing tube 3 and a filling joint material filled in the gaps between them, and is provided by integrating and solidifying these.

<Manufacturing method of cylindrical sputtering target>
When the cylindrical sputtering target 1 is manufactured, the outer peripheral surface of the cylindrical backing tube 1 and the inner peripheral surface of the target material 2 are used as joint surfaces, and the joint material provided between these joint surfaces is used for joining.
As shown in FIG. 2, a heating step of the target material 2 and the backing tube 3, a base treatment step of applying the base treatment bonding material to the target material 2 and the backing tube 3, and a base treatment for cooling and solidifying the applied base treatment bonding material. Treatment joint material cooling step, reheating step of reheating the solidified base treatment joint material, joint material filling step (joining process) of filling the gap between the target material 2 and the backing tube 3 for filling joint material, filling. It has a joint material cooling process that cools and solidifies the joint material. Hereinafter, the steps will be described in order.

(Heating process)
The target material 2 and the backing tube 3 are heated, and the inner peripheral surface of the target material 2 and the outer peripheral surface of the backing tube 3 which are the joint surfaces thereof are heated to a temperature equal to or higher than the melting point (or liquidus temperature) of the base-treated joint material. To do.

(Base treatment process)
In the heating step, the base treatment bonding material in the molten state is applied to the inner peripheral surface of each of the divided target materials 2a in the heated state and the outer peripheral surface of the backing tube 3, respectively, to form the base treatment layers 41a and 41b, respectively. In this case, by applying the base treatment bonding material while applying ultrasonic vibration with an ultrasonic soldering iron (not shown) equipped with a heater, dirt on the inner peripheral surface of the divided target material 2a and the outer peripheral surface of the backing tube 3 can be prevented. Removal of the oxide film and the like are promoted, and the surface-treated bonding material can be applied to these surfaces.
The base treatment step may be carried out in the atmosphere, but when carried out in an inert atmosphere such as argon or nitrogen, oxidation of the surfaces of the base treatment layers 41a and 41b formed by the base treatment bonding material is suppressed. It is desirable to carry out in such an atmosphere.

(Base treatment joint material cooling process)
The base treatment joint material cooling step is performed by an appropriate cooling means after the base treatment step. As a result, the base treatment bonding material is solidified, and as shown in FIGS. 3 and 4, the base treatment layers 41a and 41b are formed on the inner peripheral surface of each divided target material 2a and the outer peripheral surface of the backing tube 3. Become. An oxide film 42 is formed on the surfaces of the base treatment layers 41a and 41b.
In this case, the base treatment layers 41a and 41b are formed so as to have a thickness of 0.1 mm or more and 0.8 mm or less. If the thickness of the base treatment layers 41a and 41b is less than 0.1 mm, the oxide film 42 is less likely to be destroyed because it is less likely to hang down even if it is in a semi-molten state in the reheating step described later. If the thicknesses of the base treatment layers 41a and 41b exceed 0.8 mm, the base treatment process takes time, and when the base treatment layers hang down due to their own weight, the thickness of the lower end portion becomes too large, and the backing tube 3 is attached to the target material 2. May not be able to be inserted.
Further, the sum of the thicknesses of the base treatment layers 41a and 41b of both the inner peripheral surface of the target material 2 and the outer peripheral surface of the backing tube 3 may be set to 0.2 mm or more and 0.9 mm or less. If the sum of these thicknesses is less than 0.2 mm, the thickness of any of the base treatment layers is less than 0.1 mm, and if it exceeds 0.9 mm, the backing tube 3 cannot be inserted into the target material 2. There is a risk. The gap between the inner peripheral surface of the target material 2 and the outer peripheral surface of the backing tube 3 is 0.5 mm or more and 1.0 mm or less, and the sum of the thicknesses of the base treatment layers 41a and 41b is 0.2 with respect to this gap. The ratio should be 0.9 or more and 0.9 or less. For example, when the gap is 1.0 mm, the sum of the thicknesses of the base treatment layers is preferably 0.2 mm or more and 0.9 mm, and when the gap is 0.5 mm, the sum of the thicknesses of the base treatment layers is 0.10 mm or more and 0. It is preferably 45 mm or less. That is, it is preferable that (sum of thicknesses of the base treatment layer) / (gap) = 0.2 to 0.9.

Further, after the base treatment layers 41a and 41b are cooled and solidified, the oxide film 42 on the surface is scraped off by a cutter or the like. By the work of scraping off the oxide film 42, the surfaces of the base treatment layers 41a and 41b are in a scratched state. Alternatively, at least the surface may be scratched by a cutter or the like without removing the oxide film 42. It is preferable that the scratches have a depth equal to or greater than the thickness of the oxide film 42 formed on the base treatment layers 41a and 41b, and reach the bonding material under the oxide film 42.

(Reheating process)
The divided target material 2a on which the base treatment layer 41a is formed is placed on the mounting table 11 shown in FIG. 5 in a state of being vertically connected. A recess 12 having an inner diameter substantially the same as the inner diameter of the target material 2 is provided on the surface of the mounting table 11, and the target material 2 is arranged so as to surround the recess 12. On the other hand, the lower end of the backing tube 3 is closed with a stopper 6 to prevent the bonding material from entering the backing tube 3.
The recess 12 is filled with the filling bonding material 40 in a molten state. As the filling bonding material 40, the same material as the base treatment bonding material is used, and in this example, pure indium or an indium alloy is filled.

In this case, an annular spacer 5 is interposed between the split target materials 2a connected vertically. The annular spacer 5 absorbs the dimensional error in the length direction of the divided target material 2a and the surface roughness of the end face, and has a function of arranging the divided target material 2a coaxially and a gap generated between the divided target material 2a. It has the function of packing to close, and can accurately connect the divided target materials 2a to each other in the length direction (height direction).
The annular spacer 5 is formed of an elastic resin material or the like, and in the present embodiment, it is formed of PTFE (polytetrafluoroethylene).
Since the annular spacer 5 is removed after the target material 2 and the backing tube 3 are joined, the outer diameter of the annular spacer 5 is set to be larger than the outer diameter of the target material 2 so that it can be easily taken out.

Further, a saucer 7 for receiving the filling joining material 40 overflowing from the gap between the target material 2 and the backing tube 3 is provided at the upper end of the target material 2.
Then, as shown in FIG. 5, the backing tube 3 is coaxially arranged inside the target material 2 with about 80% of the total length inserted. In the state shown in FIG. 5, it is assumed that the oxide film 42 has been removed, but it may remain on the surfaces of the base treatment layers 41a and 41b.
Then, after assembling in the state shown in FIG. 5, the target material 2 and the backing tube 3 are heated by a heater (not shown) arranged around the target material 2. For example, by heating at 200 ° C. for 1 to 2 hours, the base treatment layers 41a and 41b are melted or at least semi-melted. By reheating at this time, the surfaces of the base treatment layers 41a and 41b are oxidized to form an oxide film 42. As described above, the base treatment layers 41a and 41b are formed to have a large thickness and the surface is scratched. Therefore, as shown in FIG. 6, the base treatment layers hang down due to their own weight at the time of melting and flow down to the lower end portion. , The oxide film 42 is destroyed.

(Joint material filling process (joining process))
As shown by the arrow in FIG. 6, when the lower end side of the backing tube 3 is inserted into the recess 12 of the mounting table 11, the target is pushed out from the recess 13 as shown in FIG. The gap between the inner peripheral surface of the material 2 and the outer peripheral surface of the backing tube 3 is raised, and the filling joining material 40 is filled between the inner peripheral surface of the target material 2 and the outer peripheral surface of the backing tube 3.
At this time, since the oxide film 42 on the surfaces of the base treatment layers 41a and 41b is divided, it is pushed up by the filling bonding material 40 rising in the gap and discharged into the saucer 7. Further, even if a part of the oxide film 42 remains in the filling bonding material 40, it is integrally filled in the gap while being dispersed in the filling bonding material 40.

The volume of the recess 12 of the mounting table 11 is the volume of the gap formed between the outer peripheral surface of the backing tube 3 and the inner peripheral surface of the target material 2 when the lower end of the backing tube 3 is inserted near the bottom surface. It suffices to have a volume or more, and it is preferable that the filling joint material 40 that has risen in the gap slightly overflows to the upper end side of the target material 2.
In this case, it can be confirmed that the filling joint material 40 is filled between the target material 2 and the backing tube 3 without a gap in a state where the filling joint material 40 overflows the saucer 7 at the upper end of the target material 2.

By inserting the lower end of the backing tube 3 to the vicinity of the bottom surface of the recess 12 in this way, the filling joining material 40 is filled in the gap between the target material 2 and the backing tube 3 without any gap.
Although not necessarily limited, the above-mentioned reheating step and joining material filling step (at least until the filling is completed) may be carried out in an inert atmosphere to suppress oxidation of the joining material and further join. The strength can be improved.

(Joint material cooling process)
After filling the gap between the target material 2 and the backing tube 3 with the filling joint material 40, the target material 2 and the backing tube 3 are integrated by the joint portion 4 by cooling and solidifying the joint material 40.
After that, the annular spacer 5, the saucer 7, the protruding joint material, and the like are removed and cleaned to obtain the cylindrical sputtering target 1.

By the method described above, the base treatment layers 41a and 41b are formed thickly, the surface is scratched, and the base treatment layers 41a and 41b hang down by their own weight by putting them in a semi-molten state at the time of reheating. The oxide film 42 is broken and divided on the surface of the above, and then the gap between the backing tube 3 and the target material 2 is filled with the filling bonding material 40. Therefore, the integration of the filling bonding material 40 and the base-treated bonding materials 41a and 41b is not hindered by the oxide film 42, and these bonding materials can be integrated while being improved, and a cylindrical mold having excellent quality. The sputtering target 1 can be manufactured.
Moreover, the influence of the oxide film 42 can be suppressed by a simple operation of forming thick base treatment layers 41a and 41b on the target material 2 and the backing tube 3 and scratching the surface thereof, and the target. The material 2 and the backing tube 3 can be firmly joined.

8 to 10 show the manufacturing method of the second embodiment of the present invention. In addition, in this embodiment and after, the same part as the said embodiment is represented by the same code, and the description thereof will be omitted. Hereinafter, the same applies to the embodiment shown in FIG.
In this second embodiment, the inner peripheral portion of the annular spacer 51 provided between the target materials 2 is projected inward in the radial direction from the inner peripheral surface of the target material 2, and backing during the joining material filling step is performed. When the tube 3 is inserted into the target material 2, the oxide film 42 of the base treatment layer 41b of the backing tube 3 is scraped off by the annular spacer 51.
That is, the inner peripheral portion of the annular spacer 51 provided on the target material 2 projects inward in the radial direction of the divided target material 2a, and the inner diameter thereof is substantially the same as the outer diameter of the backing tube 3 (matched diameter or slightly). It is formed with a small diameter or a slightly large diameter).
Further, as shown in FIG. 9, the scraping plate (annular spacer) 51 is provided with a hole 55 and a notch 56. In these holes 56 and the cut portion 57, the molten filling bonding material can flow through the holes 55 and the cut portion 56 in the joining step. The holes 55 and the cut portions 56 may be provided in any shape, formation position and number other than the shape shown in FIG. 9, and if the molten filling joint material can pass through, the holes may be provided. Only one of 55 or the notch 56 may be formed.

In the case of the second embodiment, the base treatment layer 41a on the inner peripheral surface of the target material 2 is formed to be thick as in the first embodiment, but the base treatment layer 41b of the backing tube 3 is the base of the target material 2. It is formed thinner than the treatment layer 41a. The thick base treatment layer 41a is used as the first base treatment layer, and the thin base treatment layer 41b is used as the second base treatment layer. Therefore, in the case of the first embodiment, both the base treatment layers 41a and 41b are the first base treatment layers.
Further, after the base treatment bonding material cooling step, the surface oxide film 42 is removed from each of the base treatment layers 41a and 41b, or at least the base treatment layers 41a and 41b are scratched.

Then, in the joining step, as shown in FIG. 8, the lower end portion of the backing tube 3 is inserted into the upper end portion of the target material 2 and these are reheated. By this reheating, the oxide film 42 is formed on both the base treatment layers 41a and 41b, and the base treatment layer 41a (first base treatment layer) of the target material 2 is thick and therefore hangs down. The oxide film 42 is also formed on the base treatment layer 41b (second base treatment layer) of the backing tube 3, but it does not hang down because the base treatment layer 41b is thin.
Then, when the backing tube 3 is inserted into the target material 2 in this heated state, the inner diameter of the scraping plate 51 provided on the target material 2 is formed to be substantially the same as the outer diameter of the backing tube 3. Therefore, when the backing tube 3 is inserted, the inner peripheral portion of the scraping plate 51 rubs the outer peripheral surface of the backing tube 3, and the oxide film 42 on the outer peripheral surface is scraped off. The scraped oxide film 42 is in a destroyed state as a film, is pushed up by the filling bonding material 40 rising in the gap, and is discharged into the saucer 7. Further, even if a part of the oxide film 42 remains in the filling bonding material 40, it is integrally filled in the gap while being dispersed in the filling bonding material 40.
On the other hand, on the outer peripheral surface of the backing tube 3 after the oxide film 42 is removed by the scraping plate 51, the base treatment layer 41b without the oxide film 42 remains thin, and the filling bonding material 40 is formed on the base treatment layer 41b. It fits evenly and integrates.
Since the base treatment layer 41a (first base treatment layer) on the inner peripheral surface of the target material 2 is thick, it is in a hanging state as in the first embodiment, and the oxide film 42 is also destroyed.

In the example shown in FIG. 8 and the like, the target material 2 is composed of three divided target materials 2a, and each annular spacer 51 between the divided target materials 2a functions as a scraping plate. Was projected from the split target material 2a, but as a scraping plate, any one of the annular spacers was provided with the function, and the other annular spacer 5 was the same as that of the first embodiment. The inner peripheral edge may be formed to have the same inner diameter as the split target material 2a, or the inner peripheral portions of all the annular spacers may be projected inward in the radial direction from the split target material 2a to function as a scraping plate. Good.
By removing the annular spacer 51 after joining, the thickness of the joint portion 4 becomes thinner in the portion where the annular spacer 51 is provided, as shown in FIG.
Further, the inner peripheral portion of the saucer 7 at the upper end of the target material 2 may be projected inward in the radial direction in the same manner as the annular spacer 51, and the inner peripheral portion thereof may be used as a scraping plate. In this case, it may be used in combination with the annular spacer 51 as a scraping plate.

FIG. 11 shows a state in the middle of manufacturing the manufacturing method according to the third embodiment of the present invention.
In the second embodiment described above, the oxide film of the base treatment layer 41b of the backing tube 3 is scraped off, but in this third embodiment, the oxide film 42 of the base treatment layer 41a of the target material 2 is removed. I have to. That is, the scraping plate 8 is provided at the lower end of the backing tube 3, and when the backing tube 3 is inserted into the target material 2, the base treatment layer on the inner peripheral surface of the target material 2 is formed at the outer peripheral portion of the scraping plate 8. The oxide film 42 of 41a is scraped off. The base treatment layer 41a of the target material 2 is formed to be thin, and the base treatment layer 41b of the backing tube 3 is formed to be thick. That is, in this embodiment, the base treatment layer 41a of the target material 2 is the second base treatment layer, and the base treatment layer 41b of the backing tube 3 is the first base treatment layer.
In this case, the scraping plate 8 may be fixed to the stopper 6 described above. The scraping plate 8 is formed so that the outer diameter is substantially the same as the inner diameter of the target material 2 (matched diameter, slightly smaller diameter, or slightly larger diameter).

The oxide film 42 scraped from the inner peripheral surface of the target material 2 by the scraping plate 8 flows into the recess 12 and mixes with the filling bonding material 40 filled in the recess 12, but the film is destroyed. Therefore, it is not formed into a film again.
The oxide film 42 formed on the base treatment layer 41b of the backing tube 3 hangs down and is destroyed by reheating because the base treatment layer 41b is formed thick.

In the above-described embodiment, the base treatment bonding material is applied to both the target material 2 and the backing tube 3, but if either surface is easily wetted with the filling bonding material 40, the surface thereof The application of the base treatment bonding material may be omitted. In other words, at the time of the joining step, the base treatment bonding material may be applied to at least one of the target material 2 and the backing tube 3 to form the base treatment layer 11.

An experiment was conducted to confirm the effect of the present invention. As the target material and the backing tube, those of the materials shown in Table 1 were used, and the base-treated joint layer was formed to the thickness shown in Table 1, respectively. SIZ, which is the target species of Example 6, is an oxide sintered body of Si, In, and Zr, and AZO of Example 7 is an oxide sintered body of Al, Zn, and is of Example 8. CuGa is an alloy of Cu and Ga, CuNi of Example 9 is an alloy of Cu and Ni, and CuCuO of Example 10 is a sintered body of Cu and CuO. The gap between the target material and the backing tube was 1.0 mm.
An In solder material was used as the base treatment bonding material. In the base treatment, heat with warm air until the surface temperature reaches 240 ° C to 260 ° C, apply the base treatment bonding material in the air atmosphere using an ultrasonic soldering iron, and when the surface is uniformly wet, The molten bonding material was dropped, and the target material and the backing tube were thickly coated while rotating, and cooled to room temperature.
For the thickness of the base treatment layer, the thickness of the target material and the backing tube was measured at any 8 points before and after the base treatment layer was formed, and the average value of the 8 points was calculated (after the base treatment layer was formed). The thickness of the base treatment layer was determined by (the average value of the thickness before formation of the base treatment layer-the average value of the thickness before the formation of the base treatment layer).
After joining, the joining area ratio was measured by an ultrasonic flaw detection inspection device. The joint area ratio is the ratio of the joined area excluding the defective joint to the total area of the joint surface between the target material and the backing tube. It can be passed when the joint area ratio is 90% or more.

Further, in Examples 1 to 10 and Comparative Examples 1 and 2, the scraping plate was not installed and scraping was not performed. In Example 11, a scraping plate was installed as shown in FIG. 11, and the inner peripheral surface of the target was scraped. In Example 12, a scraping plate was installed as shown in FIG. 8, and the outer peripheral surface of the backing tube was scraped.
These results are shown in Table 1. In the table, BT indicates a backing tube and TG indicates a target material.

As can be seen from Table 1, when the thickness of at least one of the base treatment layer of the target material and the backing tube was 0.1 mm or more and 0.8 mm or less, the joint area ratio was 90% or more.
On the other hand, in Comparative Example 1 and Comparative Example 2, the bonding ratio was less than 90% because the thickness of the base treatment layer was small for both the target material and the backing tube.

1 Cylindrical sputtering target 2 Cylindrical target material 2a Divided target material 3 Cylindrical backing tube 4 Joint 40 Filling joint material 41a, 41b Base treatment layer 42 Oxidation film 5 Circular spacer 51 Circular spacer (scraping plate)
55 Hole 56 Notch 6 Plug 7 Receiving tray 8 Scraping plate 11 Mounting stand 12 Recess

Claims (2)

A method for manufacturing a cylindrical sputtering target, wherein the gap between the inner peripheral surface of the cylindrical target material and the outer peripheral surface of the cylindrical backing tube inserted inside the cylindrical target material is filled with a joining material to join. A base treatment bonding material is applied to at least one member of the inner peripheral surface of the cylindrical target material and the outer peripheral surface of the cylindrical backing tube to form a first base treatment layer of 0.1 mm or more and 0.8 mm or less. After the base treatment step and the base treatment step, the cylindrical backing tube is inserted into the cylindrical target material, and a bonding material for filling in a molten state is inserted in the gap between the cylindrical target material and the cylindrical backing tube. In the base treatment step, at least the surface of the first base treatment layer is scratched, and in the joining step, at least the surface of the first base treatment layer is in a semi-molten state. A method for producing a cylindrical sputtering target, which comprises filling the filling bonding material after heating until In the base treatment step, a second base treatment layer thinner than the first base treatment layer is formed on the other member on the opposite side of the one member on which the first base treatment layer is formed. A scraping plate that can be arranged so as to project radially in the gap is provided along the circumferential direction on the one member on which the first surface treatment layer is formed, and the scraping is performed in the joining step. The cylinder according to claim 1, wherein the cylindrical backing tube is inserted into the cylindrical target material while scraping at least a part of the oxide film formed on the surface of the second surface treatment layer by the plate. Manufacturing method of type sputtering target.

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