JP6464666B2 - Cylindrical target material and manufacturing method thereof, and cylindrical sputtering target and manufacturing method thereof - Google Patents

Description

  The present invention relates to a cylindrical target material made of a cylindrical ceramic sintered body and a method for manufacturing the same. Moreover, this invention relates to the cylindrical sputtering target using this cylindrical target material, and its manufacturing method.

  Conventionally, a flat plate is generally used as a sputtering target. However, when this flat plate target is used for sputtering by a magnetron sputtering method, the use efficiency is 20% to 30%. It stays. This is because in magnetron sputtering, plasma is concentrated and collides with a specific part of a flat target by a magnetic field, causing a phenomenon in which erosion proceeds to a specific part of the target surface, and the deepest part reaches the backing plate in the target. This is because the life of the target is reached.

  In response to this problem, it has been proposed to increase the usage efficiency of the target by making the sputtering target cylindrical. This sputtering method uses a cylindrical sputtering target consisting of a cylindrical backing tube and a cylindrical target material formed on the outer periphery thereof, and a magnetic field generating facility and a cooling facility are installed inside the backing tube to form a cylindrical shape. Sputtering is performed while rotating the sputtering target. It is said that the use efficiency of the target can be increased to 60% to 70% by using the cylindrical sputtering target.

  As a material for such a cylindrical sputtering target, a metal material that can be easily processed into a cylindrical shape and has high mechanical strength is widely used. However, ceramic materials have low mechanical strength and are brittle. It has not yet spread.

  At present, ceramic cylindrical sputtering targets are manufactured by spraying ceramic powder on the outer periphery of a cylindrical backing tube or by filling ceramic powder on the outer periphery of a cylindrical backing tube. It is limited to a hot isostatic pressing (HIP) method, etc., in which ceramic powder is fired in an inert atmosphere. However, the thermal spraying method has a problem that it is difficult to obtain a high-density target, and the HIP method has a problem that the initial cost and running cost are high, peeling due to a difference in thermal expansion, and further, the target cannot be recycled. .

  On the other hand, in Japanese Patent Application Laid-Open No. 2013-147368, a cylindrical ceramic molded body is formed by a cold isostatic press (CIP) method, and the cylindrical ceramic sintered body is processed into a predetermined shape by firing this. After that, a method of manufacturing a cylindrical sputtering target by joining with a backing tube has been proposed. Here, when trying to obtain a cylindrical ceramic molded body by the CIP method, the raw material powder or this was slurried and granulated inside a mold consisting of a soft upper and lower lid and outer frame and a hard inner frame. It is necessary to fill the granulated powder and press the mold using a cold isostatic pressure (CIP) press.

  However, it is difficult to simultaneously apply water pressure to each part of the mold during CIP molding. That is, in such a CIP method, the outer peripheral part of the soft upper and lower lids not supported by the hard inner frame and the center part of the outer frame are first affected by pressure, and the flow of the raw material powder starts from this part, Pressure is transmitted to both axial ends and the inner diameter side. For this reason, depending on the size and shape of the target cylindrical ceramic molded body or the conditions at the time of CIP molding, a large distortion may occur such that the roundness is 0.50 mm or more. Such a large strain remains even after firing, which is a serious problem when manufacturing a cylindrical sputtering target by the CIP method.

  In contrast, JP-A-2005-281862 discloses an eccentricity of the inner and outer diameters (outer diameter center and inner diameter) by fixing a fired cylindrical ceramic molded body to a jig and processing it using a lathe. It is described that the center deviation) can be 0.2 mm or less.

  However, the problem in this document is a relatively small strain that occurs in the firing process, and not a large strain that occurs during CIP molding and has a roundness of 0.50 mm or more. In addition, in this document, no specific explanation is given on how to suppress the eccentricity of the inner and outer diameters.

  Therefore, according to the method described in Japanese Patent Application Laid-Open No. 2005-281862, a cylindrical ceramic sintered body that has undergone large distortion during CIP molding is processed with high accuracy without causing defects such as cracks and chips. Is considered difficult. That is, in the method described in Japanese Patent Application Laid-Open No. 2005-281862, it is difficult to apply pressure evenly during chucking (fixing) to a fixing jig due to large distortion of the cylindrical ceramic sintered body. There is a possibility that a defect may occur in a portion where a large force is applied locally. Even if such a defect does not occur, stable chucking is impossible, so that the processing accuracy is deteriorated, and the obtained cylindrical target material and the cylindrical sputtering target bonded to the backing tube are obtained. Eccentricity is inevitable. In particular, when a plurality of cylindrical target materials are arranged and joined to a single backing tube, the effect of such eccentricity becomes large, resulting in steps on the outer peripheral surface of adjacent cylindrical target materials. Variations may occur in the interval between the end faces of the cylindrical target material. As a result, a smooth rotation of the cylindrical sputtering target cannot be obtained during sputtering, and abnormal discharge (arcing) is induced.

  From the above, the conventional techniques including Japanese Patent Application Laid-Open No. 2005-281862 are characterized by a cylindrical sputtering target that is excellent in roundness and concentricity when large distortion occurs during CIP molding. Therefore, it is considered extremely difficult to stably realize high target usage efficiency.

JP 2013-147368 A JP 2005-281862 A

  The present invention can eliminate such a large distortion even when a large distortion occurs such that the roundness is 0.50 mm or more during CIP molding, and the roundness and concentricity can be reduced. An object of the present invention is to provide an excellent cylindrical target material and a method for producing the same. Moreover, an object of this invention is to provide the cylindrical sputtering target using this cylindrical target material, and its manufacturing method.

  The method for producing a cylindrical target material of the present invention includes a forming step of forming a cylindrical ceramic formed body by cold isostatic pressing, and a firing step of firing the cylindrical ceramic formed body to obtain a cylindrical ceramic sintered body. And after grinding the one end surface and the other end surface of the cylindrical ceramic sintered body with a surface grinder having a table, the outer peripheral surface of the cylindrical ceramic sintered body is ground with a cylindrical grinder, A machining step of grinding an inner peripheral surface of the cylindrical ceramic sintered body with an internal grinder, and in the grinding with the surface grinder, the cylindrical ceramic sintered body is placed on the table on the one end surface. Is placed so that the distance between the surface of the table and the one end surface is within 0.80 mm. Fixed, characterized by grinding the end surface.

In grinding by the circular cylinder Labs Kezuban, the cylindrical ceramic sintered body, it is preferably fixed to the fixing jig of the cylindrical grinding machine through a temporary bonding adhesive. In this case, the adhesive layer was formed by applying the temporary fixing adhesive surface of the fixing jig, the adhesive layer, is brought into contact with the other end face of the cylindrical ceramic sintered body, the fixed After controlling the variation of the distance from the surface of the jig to the one end surface to be within 0.30 mm, the cylindrical ceramic sintered body is fixed to the fixing jig, and the outer peripheral surface is ground. It is preferable.

  In grinding by the surface grinder, when grinding the one end face, at least one thickness gauge is inserted between the table and the other end face, and the distance from the table surface to the one end face is set. It is preferable to control so that the variation is within 0.80 mm. In this case, the total grinding amount of the one end face and the other end face is 0.10 mm to 0 in the maximum thickness among the thicknesses of at least one thickness gauge inserted between the table and the other end face. More preferably, 20 mm is added.

  The present invention can be suitably applied when the roundness of the cylindrical ceramic sintered body after the firing step is 0.50 mm or more.

  The cylindrical target material of the present invention is obtained by the above-described manufacturing method, and has a roundness of 0.30 mm or less and a concentricity of 0.30 mm or less.

  Although the present invention is not limited by the size of the cylindrical target material, in particular, the outer diameter is 80 mm to 200 mm, the inner diameter is 40 mm to 190 mm, the wall thickness is 5 mm to 20 mm, and the total length is 50 mm to 500 mm. It can apply suitably with respect to a cylindrical target material.

  In the method for producing a cylindrical sputtering target of the present invention, a single backing tube is coaxially arranged in a hollow portion of at least one cylindrical target material, and then joined to a gap between the cylindrical target material and the backing tube. A method of manufacturing a cylindrical sputtering target, in which a layer is formed and the cylindrical target material and the backing tube are joined, wherein the above-described cylindrical target material is used as the cylindrical target material .

  The cylindrical sputtering target of the present invention includes at least one cylindrical target material, a single backing tube disposed coaxially in a hollow portion of the cylindrical target material, the target material and the backing tube. A cylindrical sputtering target comprising a bonding layer formed in a gap therebetween, wherein the cylindrical target material is the above-described cylindrical target material.

  According to the present invention, even when a large strain is generated such that the roundness is 0.50 mm or more during CIP molding, such a large strain can be eliminated, and the roundness and concentricity can be eliminated. It is possible to provide a cylindrical target material excellent in temperature and a method for manufacturing the same. Moreover, according to this invention, the cylindrical sputtering target using such a cylindrical target material and its manufacturing method can be provided. In particular, according to the present invention, even when a plurality of cylindrical target materials are coaxially arranged and joined to a single backing tube, the outer peripheral surface and end surface of each cylindrical target material can be used as a reference. Since the alignment can be easily performed, it is possible to suppress the variation in the step between the outer peripheral surfaces of the adjacent cylindrical target materials and the gap between the opposing end surfaces. Such a cylindrical sputtering target of the present invention has high target use efficiency, and the cylindrical target material is hardly peeled off during sputtering, and abnormal discharge or film formation abnormality hardly occurs. For this reason, the industrial significance of the present invention is extremely large.

FIG. 1 is a schematic cross-sectional view for explaining grinding of one end face of a cylindrical ceramic sintered body. FIG. 2 is a schematic cross-sectional view for explaining grinding of the other end face of the cylindrical ceramic sintered body. FIG. 3 is a schematic cross-sectional view for explaining grinding of the outer peripheral surface of the cylindrical ceramic sintered body. FIG. 4 is a schematic cross-sectional view for explaining grinding of the inner peripheral surface of the cylindrical ceramic sintered body.

  In order to solve the above-described problems, the present inventors have made extensive studies on a processing method and a processing process of a cylindrical ceramic sintered body. As a result, it was concluded that the cause of the above-mentioned problem is that, when a cylindrical ceramic molded body in which a large strain is generated during CIP molding is processed, the chucking becomes unstable. That is, conventionally, when chucking a workpiece in a machining process, a fixing jig such as a three-jaw scroll chuck is often used, but such chucking is distorted in the workpiece to be machined. This is based on the assumption that there is little or a holding allowance (a portion chucked on the fixing jig) is secured. Therefore, in processing of a cylindrical ceramic sintered body with a large strain, pressure cannot be applied evenly during fixing, and the cylindrical ceramic sintered body has defects such as cracks and chips during chucking or processing. Will occur.

  Conventionally, in machining of a cylindrical workpiece in industrial scale production, it is common to use a lathe capable of collectively machining an end face, an outer peripheral face and an inner peripheral face. However, machining by lathe (cutting) has a large incision amount (the thickness of the workpiece peeled off from the surface on which the blade or the grindstone is cut at the time of cutting or grinding) as large as about 50 μm to 500 μm. When a cylindrical ceramic sintered body made of a brittle material such as indium (ITO) or aluminum-doped zinc oxide (AZO) is processed by a lathe, a large number of fine cracks remain in the processed cylindrical target material. Become. As a result, when a cylindrical target material was heated at the time of joining with a backing tube, it discovered that these cracks started as a defect.

  As a result of further studies on these points, the present inventors have found that a cylindrical ceramic sintered body is produced even when a large strain is generated such that the roundness is 0.50 mm or more during CIP molding. The knowledge that by optimizing the processing means, processing sequence, etc. when processing the above, we can eliminate such large distortions and produce a cylindrical target material with excellent roundness and concentricity. Obtained. The present invention has been completed based on this finding.

1. Manufacturing method of cylindrical target The manufacturing method of the cylindrical target material of the present invention includes a forming step of forming a cylindrical ceramic formed body by cold isostatic pressing, firing the ceramic formed body, And a processing step of grinding the end surface, outer peripheral surface and inner peripheral surface of the cylindrical ceramic sintered body. In particular, in the manufacturing method of the present invention, in the machining process, the end surface is ground by a surface grinder (end surface grinding), the outer surface is ground by a cylindrical grinder (outer surface grinding), and the inner surface is ground by an internal grinder. It is important to perform the grinding (inner peripheral surface grinding) in this order. In addition, after controlling the dispersion of the distance from the surface of the table of the surface grinder to the one end face of the cylindrical ceramic sintered body to a specific range during end face grinding, grinding the one end face and grinding the other end face It is important to do. Hereinafter, the present invention will be described in detail for each process, but portions that are the same as those of the prior art will be omitted or simplified.

(1) Raw material The raw material of the target material of this invention can be suitably selected according to the use, and is not restrict | limited in particular. For example, it is possible to use an oxide powder whose main component is indium (In), tin (Sn), zinc (Zn), aluminum (Al), niobium (Nb), tantalum (Ta), titanium (Ti), and the like. it can.

(2) Molding step The molding step is a slurry obtained by adding water, a binder and a dispersant to the above-described oxide powder, and spray-drying the slurry to obtain a granulated powder, followed by press molding. This is a step of obtaining a cylindrical ceramic molded body.

  In this case, as a forming method, a method of first forming the granulated powder into a cylindrical shape by a die forming method and then performing a secondary forming by a cold isostatic pressing (CIP) method can be employed. Alternatively, a method in which the granulated powder is filled in a rubber mold and directly molded by the CIP method can be employed. In any case, from the viewpoint of obtaining a high-density cylindrical target material, the molding is preferably performed at a pressure of 100 MPa or more, more preferably 200 MPa or more. If the pressure is less than 100 MPa, a high-density cylindrical target material cannot be obtained. The upper limit of the pressure is not particularly limited, but is preferably 500 MPa or less in consideration of the durability of the apparatus.

  As the rubber mold, one constituted by an upper and lower lid, an inner frame and an outer frame can be used. As the material of the rubber mold, for example, silicon rubber can be used for the upper and lower lids, hard plastic rubber can be used for the inner frame, and soft rubber can be used for the outer frame.

  In such a molding process, a time lag occurs when water pressure acts on each part of the rubber mold during CIP molding, so that the raw material powder flows in the mold and the resulting cylindrical ceramic molded body, particularly the outer peripheral surface As a result, the end face is distorted.

(3) Firing step The firing step is a step of obtaining a cylindrical ceramic sintered body by firing and sintering the cylindrical ceramic formed body obtained in the forming step using a firing furnace.

(3-1) Degreasing process In a baking process, first, the degreasing process which decomposes | disassembles and volatilizes organic components, such as a binder and a dispersing agent, is performed from a cylindrical ceramic molded object. Specifically, the organic component is decomposed and volatilized by heating the cylindrical ceramic molded body at 300 ° C. to 500 ° C., preferably 350 ° C. to 450 ° C., for 5 hours to 30 hours, preferably 10 hours to 20 hours. . When the heating temperature is less than 300 ° C. or the heating time is less than 5 hours, a sufficient degreasing effect cannot be obtained. On the other hand, when the heating temperature exceeds 500 ° C. or the heating time exceeds 20 hours, productivity deteriorates.

  The degreasing treatment is preferably performed in an air atmosphere. Specifically, it is preferable to perform the degreasing process in a state where the atmosphere gas (air) is circulated at a rate of about 5 L / min to 30 L / min in the firing furnace. By circulating air at such a flow rate, the furnace temperature can be controlled within a range of ± 20 ° C. while sufficiently decomposing and volatilizing the organic components in the cylindrical ceramic molded body. A uniform cylindrical target material can be obtained.

(3-2) Firing After the degreasing treatment, it is necessary to heat and sinter the cylindrical ceramic molded body at a higher temperature. At this time, it is preferable to control the heating rate to 15 ° C./hr to 150 ° C./hr or less. Thereby, it is possible to effectively discharge the voids existing inside the cylindrical ceramic molded body to the outside. On the other hand, when the rate of temperature rise is less than 15 ° C./hr, the productivity is significantly deteriorated. On the other hand, when the rate of temperature rise exceeds 150 ° C./hr, the temperature distribution in the furnace becomes non-uniform, making it difficult to obtain a uniform cylindrical target material. From the viewpoint of making the temperature distribution in the furnace uniform and allowing the grain growth inside the cylindrical ceramic molded body to proceed uniformly, the temperature rising rate is more preferably 130 ° C./hr or less, and 100 ° C./hr. More preferably, it is as follows.

  In the firing step, the sintering temperature of the cylindrical ceramic formed body needs to be appropriately selected according to the composition so that the obtained cylindrical target material has a sufficiently high density. For example, when a cylindrical ceramic molded body containing indium oxide as a main component is fired, the sintering temperature is preferably 1200 ° C to 1600 ° C, and more preferably 1300 ° C to 1600 ° C. On the other hand, when firing a cylindrical ceramic molded body containing zinc oxide as a main component, the sintering temperature is preferably 1200 ° C to 1400 ° C, and more preferably 1250 ° C to 1350 ° C.

  The firing time (sintering time) at the sintering temperature described above is preferably 5 to 40 hours, preferably 10 to 30 hours, considering the balance between sinterability and productivity. More preferably, it is more preferably 15 hours to 25 hours. If the sintering time is less than 5 hours, it is difficult to obtain a high-density cylindrical target material. On the other hand, when the sintering time exceeds 40 hours, the distortion of the cylindrical target material becomes large, and the reduction reaction proceeds, so that the volatilization amount of the metal component is remarkably increased.

  Note that the atmosphere during firing is preferably an oxidizing atmosphere, and more preferably a pure oxygen atmosphere. Specifically, it is preferable to perform firing in a state where oxygen is circulated at a rate of about 5 L / min to 30 L / min in the firing furnace. Thereby, since the furnace temperature can be controlled within a range of ± 20 ° C. while suppressing the generation of oxygen vacancies, it becomes possible to obtain a high-density and uniform cylindrical target material.

(3-3) Cylindrical Ceramic Sintered Body The cylindrical ceramic sintered body obtained in this way basically takes over the large strain generated during the above-described CIP molding. Accordingly, the cylindrical ceramic sintered body has a strain with a roundness α ₀ of 0.50 mm or more and a concentricity β ₀ of 1.0 mm or more, although it varies depending on conditions at the time of CIP molding and the configuration of the mold. It often happens.

Here, the roundness α ₀ of the cylindrical ceramic sintered body means a value obtained by the diameter method. Specifically, when the outer diameter d ₀ of the cylindrical ceramic molded body is measured at any eight locations, and the maximum value is d _{0 (max)} and the minimum value is d _{0 (min)} , It can be obtained in (a).
Roundness: α ₀ = (d _{0 (max)} −d _{0 (min)} ) / 2 (a)

In addition, the concentricity β _{0 of} the cylindrical ceramic sintered body means the uneven thickness (thickness variation), and the thickness of the cylindrical ceramic sintered body is measured at 8 arbitrary points, and the maximum value is obtained. Is t _{0 (max)} and the minimum value is t _{0 (min)} , it can be obtained by the following equation (b).
Concentricity: β ₀ = t _{0 (max)} −t _{0 (min)} (b)

(4) Processing step The processing step is a step of processing the end face, outer peripheral surface and inner peripheral surface of the cylindrical ceramic sintered body obtained in the firing step to remove a large strain generated during CIP molding.

In particular, in the present invention, the roundness α ₀ is 0.50 mm or more and the concentricity β ₀ is 1 at the time of CIP molding by optimizing the processing means and processing sequence when processing the cylindrical ceramic sintered body. Even when a large strain of 0.0 mm or more occurs, such a large strain is eliminated, and the roundness α ₁ of the obtained cylindrical target material is 0.30 mm or less, preferably 0.25 mm. Hereinafter, it can be more preferably 0.20 mm or less. Further, the concentricity β ₁ can be set to 0.30 mm or less, preferably 0.20 mm or less, more preferably 0.10 mm or less.

Here, the roundness α ₁ of the cylindrical target material is the same as in the case of the cylindrical ceramic sintered body, and the outer diameter of the cylindrical target material is measured at any eight locations, and the maximum value is d _{1. When (max)} and the minimum value are d _{1 (min)} , they can be obtained by the following equation (c).
Roundness: α ₁ = (d _{1 (max)} −d _{1 (min)} ) / 2 (c)

The concentricity β ₁ of the cylindrical target material is the same as in the case of the cylindrical ceramic sintered body. The thickness of the cylindrical target material is measured at eight arbitrary positions, and the maximum value is t _{1 (max ) When} the minimum value is t _{1 (min)} , it can be obtained by the following equation (d).
Concentricity: β ₁ = t _{1 (max)} −t _{1 (min)} (d)

In addition, the processing step in the manufacturing method of the present invention can be applied without being limited by the size of the cylindrical ceramic sintered body to be processed and the distortion (roundness). However, in the following, the cylindrical ceramic sintered body having a roundness α ₀ obtained by the above-described forming step and firing step to which the present invention is preferably applied is 0.50 mm or more, Example of manufacturing a cylindrical target material having an outer diameter of 80 mm to 200 mm, an inner diameter of 40 mm to 190 mm, a wall thickness of 5 mm to 20 mm, a total length of 50 mm to 500 mm, and a roundness α ₁ of 0.30 μm or less. Will be described.

(4-1) Processing means In the manufacturing method of the present invention, grinding, specifically, a surface grinder, a cylindrical grinder, and an internal grinder are used as the processing means. These grinding processes are different from the lathe cutting process, but the end face, outer peripheral surface and inner peripheral surface of the cylindrical ceramic sintered body cannot be processed in a lump, but the cutting depth during processing is in the range of 1 μm to 30 μm. Therefore, the occurrence of fine cracks can be effectively suppressed while ensuring productivity.

(4-2) Processing Order In the manufacturing method of the present invention, as shown in FIGS. 1 and 2, first, both end faces (one end face 2 and the other end face 3) of the cylindrical ceramic sintered body 1 are ground to form a cylinder. The squareness γ of the one end face 2 and the other end face 3 with respect to the central axis of the shaped ceramic sintered body 1 is controlled to 0.30 mm or less, preferably 0.25 mm or less, more preferably 0.20 mm or less. It is necessary to control the parallelism δ to 0.20 mm or less, preferably 0.15 mm or less. Here, the squareness γ is a state in which the cylindrical ceramic sintered body 1 is fixed to the scale placed on the surface plate so that the outer peripheral surface 4 is parallel to the surface plate, It can be obtained by measuring the height of the one end surface side 2 and the other end surface side 3 at at least four locations in the circumferential direction and calculating the maximum value of the difference. Further, the parallelism δ means the degree of parallelism of the other end surface 3 or the one end surface 2 with respect to the reference surface with the one end surface 2 or the other end surface 3 as a reference, and can be obtained by, for example, a height gauge. By controlling the perpendicularity γ and the parallelism δ in this way, the cylindrical ceramic sintered body 1 is fixed to the fixing jig 10 or 13 with reference to these end faces in outer peripheral surface grinding and inner peripheral surface grinding described later. It is possible to easily adjust the position when chucking.

After end face grinding, the outer peripheral surface 4 of the cylindrical ceramic sintered body 1 is ground as shown in FIG. 3, and then the inner peripheral surface 5 is ground as shown in FIG. As described above, the cylindrical ceramic sintered body 1 formed by the CIP method has a large strain, but this strain is large on the outer peripheral surface 4 side and relatively small on the inner peripheral surface 5 side. Therefore, after the outer peripheral surface grinding that chucks the inner peripheral surface 5 with relatively small distortion to the fixing jig 10, the outer peripheral surface 4 is chucked to the fixing jig 13 with reference to the outer peripheral surface 4 obtained without distortion. By performing the inner peripheral surface grinding by king, a cylindrical target material having excellent roundness α ₁ and concentricity β ₁ can be obtained without causing defects such as cracks and chips.

  Further, in the manufacturing method of the present invention, the outer peripheral grinding is performed by a cylindrical grinder, and the inner peripheral surface grinding is performed by an inner grinder. However, in general, due to the structure of the grinder, the grindstone 14 of the inner grinder is: The outer diameter must be smaller than the grindstone 11 of the cylindrical grinder. For this reason, in the internal peripheral surface grinding, the rotational speed of the grindstone 14 cannot be set high, and the processing time becomes twice or more that of the external peripheral surface grinding, and it is difficult to improve productivity. However, in the present invention, since the inner peripheral surface grinding is performed after the outer peripheral surface grinding, the cylindrical ceramic sintered body 1 can be stably chucked to the fixing jig 13 during the inner peripheral surface grinding. The depth of cut in circumferential grinding can be set large within a predetermined range, and efficient machining becomes possible.

(4-3) End face, outer peripheral face and inner peripheral face grinding [End face grinding]
a) Fixing method In the end face grinding, first, the cylindrical ceramic sintered body 1 is placed on the table 6 of the surface grinder so that the central axis C is vertical. Here, the one end face 2 and the other end face 3 of the cylindrical ceramic sintered body 1 formed by the CIP method are greatly distorted, and it is difficult to stably chuck the cylindrical ceramic sintered body 1 as it is. It is. For this reason, the cylindrical ceramic sintered body 1 is placed from the surface of the table 6 at any eight positions in the circumferential direction in a state where the cylindrical ceramic sintered body 1 is placed on the table 6 so that the one end surface 2 is on the upper side. The distance (height) h ₀ to the one end face 2 of the ceramic sintered body 1 is measured, and the variation (difference between the maximum value and the minimum value) is within 0.80 mm, preferably within 0.70 mm, more preferably 0. It is important that the fixed blocks 8 are arranged in the four directions of the cylindrical ceramic sintered body 1 and chucked by an electromagnetic chuck after being controlled to be within 40 mm. Thereby, since the cylindrical ceramic sintered body 1 can be ground and fixed stably on the table 6, the perpendicularity γ and the parallelism δ within the above-described ranges can be easily achieved. As the fixing block 8 used at this time, it is preferable to use a block whose height is about 2/3 to 5/6 of the height h ₀ of the cylindrical ceramic sintered body. More preferably, about 5 are used. If the height of the fixed block is less than (2/3) h ₀ , the fixed block may come off during end face grinding. On the other hand, if the height of the fixed block exceeds (5/6) h ₀ , the fixed block and the grindstone 9 of the surface grinder may interfere during processing.

For example, as shown in FIG. 1, at least one piece between the other end surface 3 of the cylindrical ceramic sintered body 1 and the table 6 can be used as a means for suppressing the variation in h ₀ within 0.80 mm. A method of inserting the thickness gauge 7 can be mentioned. This is because the thickness gauge 7 has a known thickness and can easily adjust h ₀ at each measurement position. As the thickness gauge 7, a general gauge, that is, a leaf having a thickness of 0.01 mm to 1 mm can be used.

After the grinding of the one end face 2, the electromagnetic chuck is once released, and the cylindrical ceramic sintered body 1 is placed on the table 6 so that the other end face 3 is on the upper side as shown in FIG. Chuck in the same way. Since the end face 2 already has a sufficient parallelism δ, the distance h ₁ from the table 6 to the other end face 3 can be obtained without inserting a thickness gauge 7 or the like between the end face 2 and the table 6. Variation can be sufficiently suppressed.

  According to such a method, the cylindrical ceramic sintered body 1 can be chucked on the table 6 substantially vertically or vertically and stably even in industrial scale production. And it becomes possible to process the other end surface 3 with high accuracy.

b) Amount of grinding In the grinding of the one end surface 2 and the other end surface 3, the amount of grinding is not limited as long as the parallelism δ of these end surfaces can be ensured, but the yield and productivity of the cylindrical target material are not limited. In view of this, it is preferable that the amount of grinding is as small as possible. In this regard, according to the above-described method, the grinding amount of the one end face 2 and the other end face 3 is set to the thickness s (of the thickness gauge 7 inserted between the other end face 3 and the table 6 when the one end face 2 is ground. mm), the maximum thickness s _max (mm) is 0.10 mm to 0.20 mm, preferably 0.10 mm to 0.15 mm, more preferably 0.10 mm. A sufficient degree of parallelism δ can be secured.

  In addition, when the cylindrical ceramic sintered body 1 is joined to the fixing jig 10 via the temporary fixing adhesive 12 in the outer peripheral surface grinding in the next step, the total length of the cylindrical ceramic sintered body 1 after end face grinding. However, it is necessary to adjust the grinding amount so as to be longer by 1 mm or more than the total length of the target cylindrical target material. In the outer peripheral surface grinding, in order to remove the temporary fixing adhesive 12 attached to the one end surface 2 or the other end surface 3, the one end surface 2 or the other end surface 3 can be ground again after the outer peripheral surface grinding. It is necessary.

c) Grinding Method and Grinding Conditions The end face grinding method is not particularly limited. However, in consideration of machining efficiency, the plunge machining in which the grinding wheel is moved in the direction perpendicular to the grinding wheel axial direction, and the grinding wheel axis It is preferable to perform grinding in combination with a traverse process for cutting while moving the grindstone in the direction. More specifically, it is preferable to perform rough grinding by plunge processing and finish grinding by traverse processing. If end face grinding is performed only by plunge machining, the machining time can be shortened, but the desired dimensional accuracy and surface condition may not be ensured. On the other hand, when end face grinding is performed only by traverse processing, desired dimensional accuracy and surface condition can be ensured, but processing may take a long time and productivity may deteriorate.

  In this case, the one end face 2 and the other end face 3 are each preferably subjected to rough grinding and finish grinding twice or more, more preferably four times or more. Thereby, it is possible to suppress variations in the perpendicularity γ and the parallelism δ between the one end surface 2 and the other end surface 3.

  Moreover, in grinding of the one end surface 2 and the other end surface 3, it is preferable to use a grindstone 9 having a particle size of # 80 to # 240, and # 120 to # 170 in both rough grinding and finish grinding. More preferably, it is used.

  Under such conditions, in rough grinding, the cutting depth is preferably adjusted to 1 μm to 30 μm, and more preferably adjusted to 10 μm to 25 μm. When the depth of cut is less than 1 μm, there is little fear of the occurrence of defects in the cylindrical ceramic sintered body 1 during rough grinding, but the processing takes a long time and the productivity is significantly reduced. On the other hand, if the depth of cut exceeds 30 μm, the grinding resistance increases, so during rough grinding, the chucking position of the cylindrical ceramic sintered body is shifted, or in the case of remarkable, chucking comes off, It becomes difficult to suppress the occurrence of cracks and chips. Further, clogging of the grindstone increases, and in order to ensure a desired surface state, it is necessary to frequently perform dressing work, and productivity is significantly deteriorated.

  On the other hand, in finish grinding, it is preferable to adjust the depth of cut to 10 μm or less, and more preferably to 6 μm or less. If the depth of cut exceeds 10 μm, it depends on the condition of the grindstone, but the surface roughness after finish grinding becomes rough, and it is necessary to perform zero grinding several times separately, resulting in deterioration of productivity. It becomes. Here, zero grinding refers to a grinding method in which only the protrusions remaining on the grinding surface are ground and removed by moving the grindstone so that the grinding surface slides. In finish grinding, the lower limit of the cutting depth is not limited. However, if the cutting depth is less than 1 μm, it takes a long time for processing, and the productivity may be significantly reduced.

  Further, the grinding amount in finish grinding is preferably 5 μm or more, and more preferably 10 μm or more. If the grinding amount is less than 5 μm, depending on the cutting amount in the rough grinding, there may be a case where the grinding marks generated by the rough grinding cannot be removed. In finish grinding, the upper limit of the grinding amount is not limited, but in order to ensure sufficient productivity, the grinding amount is preferably 20 μm or less.

[Outer peripheral surface grinding]
a) Fixing method In the outer peripheral surface grinding, the cylindrical ceramic sintered body 1 is chucked so that the central axis C thereof coincides with the central axis of the fixing jig. At this time, when the distortion on the inner peripheral surface 5 side is relatively small, specifically, when the concentricity β ₀ of the cylindrical ceramic sintered body is less than 0.60 mm, only a general scroll chuck is used. It is also possible to chuck the shaped ceramic sintered body 1. However, when the distortion on the inner peripheral surface 5 side is large, specifically, when the concentricity β ₀ of the cylindrical ceramic sintered body 1 is 0.60 mm or more, the fixing with the scroll chuck has a sufficient fixing force. It cannot be secured. In such a case, it is preferable to bond and fix the cylindrical ceramic sintered body 1 to the fixing jig 10 via the temporary fixing adhesive 12. That is, an adhesive layer is formed by applying the temporary fixing adhesive 12 to the surface of the fixing jig 10, and one end surface 2 or the other end surface 3 of the cylindrical ceramic sintered body 1 is brought into contact with the adhesive layer, It is preferable to fix the cylindrical ceramic sintered body 1 to the fixing jig 10 by pressing as necessary.

  The temporary fixing adhesive 12 is required to be solid at room temperature (5 ° C. to 35 ° C.) and have a heat melting temperature of 50 ° C. or higher. Specifically, natural polymers such as vinyl polymer compounds, petroleum resins, rosin and derivatives thereof, thermoplastic resins such as paraffin wax, thermosetting resins, and the like can be suitably used.

In this case, in order to obtain a cylindrical target material having a roundness α ₁ of 0.30 mm or less, the perpendicularity γ and the parallelism δ of the cylindrical ceramic sintered body 1 are set to appropriate ranges by the end face processing described above. The distance h from the surface of the fixing jig 10 to the other end surface 3 or the one end surface 2 of the cylindrical ceramic sintered body 1 at any eight positions in the circumferential direction of the cylindrical ceramic sintered body 1 is controlled. It is necessary to measure ₂ and adjust the variation so that it is within 0.30 mm, preferably within 0.20 mm. Note that, according to the manufacturing method of the present invention, the one end surface 2 and the other end surface 3 of the cylindrical ceramic sintered body 1 after end face grinding described above have sufficient squareness γ and parallelism δ. Such adjustment can be easily performed.

b) Grinding amount The grinding amount in the outer peripheral surface grinding is not particularly limited, but is preferably as small as possible in consideration of yield and productivity. Specifically, it is preferable to control to the minimum grinding amount at which the roundness α ₁ of the outer peripheral surface 4 is 0.30 mm or less.

c) Grinding method and grinding conditions The outer circumferential surface grinding method and conditions are not particularly limited, but considering machining efficiency, grinding is performed by combining plunge machining and traverse machining as in the case of end face grinding. Is preferred.

  Specifically, as shown in FIG. 3, after using the grindstone 11 to cut a predetermined amount in the direction of the arrow A, the grindstone 11 is moved in the direction of the arrow B by the width, and similarly, Cut a certain amount. This operation is repeated to plunge the entire outer peripheral surface 4 of the cylindrical ceramic sintered body 1 (rough grinding). Subsequently, the grindstone 11 is moved in the direction of the arrow B while cutting a predetermined amount in the direction of the arrow A using the grindstone 11, and the entire outer peripheral surface is traversed (finish grinding). At this time, it is more preferable to perform rough grinding and finish grinding in two or more times, and more preferably in four or more times.

  In addition, as the grindstone 11, it is preferable to use the thing of # 80- # 240, and it is more preferable to use the thing of # 120- # 170 like the case of end surface grinding. At this time, it is preferable to adjust the cutting amount in rough grinding to 1 μm to 30 μm, and it is more preferable to adjust to 10 μm to 25 μm. On the other hand, the depth of cut by finish grinding is preferably adjusted to 10 μm or less, and more preferably adjusted to 6 μm or less. Furthermore, the grinding amount in finish grinding is preferably 5 μm or more, and more preferably 10 μm or more.

[Inner surface grinding]
a) Fixing Method In the inner peripheral surface grinding, the cylindrical ceramic sintered body 1 is fixed so that the central axis C thereof coincides with the central axis C of the fixing jig 13. After the outer peripheral surface grinding, the outer peripheral surface 4 of the cylindrical ceramic sintered body 1 has a high roundness α ₁ , so that even known means such as a three-jaw scroll chuck can be fixed without any problem. Can do.

b) Amount of grinding Although the amount of grinding in the outer peripheral surface grinding needs to be adjusted as appropriate according to the degree of distortion of the inner peripheral surface 5, it is preferably as small as possible as in the case of end surface grinding. In the inner peripheral surface grinding in the manufacturing method of the present invention, since the inner peripheral surface grinding is already performed in a state where the roundness α ₁ of the outer peripheral surface 4 is already secured, the amount of grinding can be reduced without using any special means. Minimized.

c) Grinding method and grinding conditions The inner circumferential surface grinding method and conditions are also not particularly limited, but it is preferable to perform a combination of plunge machining and traverse machining as in the end face grinding and outer circumferential grinding.

  Specifically, as shown in FIG. 4, after using a grindstone 14 to cut a predetermined amount in the direction of arrow A ′, the grindstone 14 is moved in the direction of arrow B ′ by the width, and similarly Cut a predetermined amount. This operation is repeated to plunge the entire inner peripheral surface 5 of the cylindrical ceramic sintered body 1 (rough grinding). Subsequently, the grindstone 14 is moved in the direction of the arrow B ′ while cutting a predetermined amount in the direction of the arrow A ′ using the grindstone 14, and the entire outer peripheral surface is traversed (finish grinding). At this time, it is more preferable to perform rough grinding and finish grinding in two or more times, and more preferably in four or more times.

  In addition, as the grindstone 14, it is preferable to use the thing of # 80- # 240, and it is more preferable to use the thing of # 120- # 170 similarly to the case of end surface grinding or outer peripheral surface grinding. At this time, it is preferable to adjust the cutting amount in rough grinding to 1 μm to 30 μm, and it is more preferable to adjust to 10 μm to 25 μm. On the other hand, the depth of cut by finish grinding is preferably adjusted to 10 μm or less, and more preferably adjusted to 6 μm or less. Furthermore, the grinding amount in finish grinding is preferably 5 μm or more, and more preferably 10 μm or more.

  In such inner peripheral surface grinding, as described above, since the cylindrical ceramic sintered body can be stably chucked, the cutting amount can be increased within a predetermined range, and efficient machining can be performed. Is possible.

2. Cylindrical target material The cylindrical target material of this invention is manufactured by the manufacturing method mentioned above. Therefore, the cylindrical target material of the present invention can be composed of the above-described raw materials, that is, oxides mainly composed of In, Sn, Zn, Al, Nb, Ta, Ti, and the like. More specifically, in addition to ITO and AZO, tantalum-doped indium oxide (ITaO), indium-doped zinc oxide (ZIO), or the like can be used.

Moreover, it can be evaluated that the cylindrical target material of the present invention has little distortion as described above. That is, this cylindrical target material has a roundness α ₁ of 0.30 mm or less, preferably 0.25 mm or less, more preferably 0.20 mm or less, and a concentricity β ₁ of 0.30 mm or less. , Preferably 0.20 mm or less, more preferably 0.10 mm or less.

  The cylindrical target material of the present invention may be formed by forming a base layer such as copper or indium on the inner peripheral surface 5 for the purpose of improving wettability with the bonding material forming the bonding layer. Good. For example, when a low melting point solder mainly composed of indium is used as the bonding material, an underlayer made of indium or an indium alloy may be formed.

3. Cylindrical Sputtering Target (1) Manufacturing Method of Cylindrical Sputtering Target The cylindrical sputtering target of the present invention includes a cylindrical target material, a backing tube, and a cylindrical tube, after the backing tube is coaxially disposed in the hollow portion of the cylindrical target material described above. It can be manufactured by forming a bonding layer by injecting a bonding material into the gap and bonding the cylindrical target material and the backing tube. Such a cylindrical sputtering target has little eccentricity and can significantly suppress the occurrence of arcing during sputtering.

The present invention can also be applied to a case where a plurality of cylindrical target materials are coaxially arranged and joined to a single backing tube. When manufacturing such a cylindrical sputtering target, if the roundness α ₁ and the concentricity β _{1 of} each cylindrical target material constituting the cylindrical sputtering target are not sufficient, it is difficult to align the adjacent cylindrical targets. A step is generated on the outer peripheral surface, and a gap between the cylindrical target materials is likely to vary. On the other hand, according to the present invention, since each cylindrical target material has excellent roundness α ₁ and concentricity β _1, by aligning with respect to this end surface or outer peripheral surface, It is possible to easily obtain a cylindrical sputtering target with little variation in steps and gaps.

[Backing tube]
The backing tube needs to have thermal conductivity that can ensure sufficient cooling efficiency so that the bonding layer does not deteriorate and melt due to heat generated during sputtering. Moreover, it is necessary to have electrical conductivity that can be discharged at the time of sputtering and to have strength that can support a cylindrical sputtering target.

  Examples of such a backing tube include those made of austenitic stainless steel, particularly SOS304, copper or copper alloy, titanium or titanium alloy, molybdenum or molybdenum alloy, aluminum or aluminum alloy, and the like. Can do. When using a stainless steel backing tube, in order to improve the wettability with the bonding material and to ensure sufficient bonding strength with the cylindrical sputtering target, the outer peripheral surface is made of copper or indium. A formation may be formed.

  The size (full length and outer diameter) of the backing tube needs to be appropriately adjusted according to the size (full length and inner diameter) of the cylindrical target material to be joined thereto. In particular, it is important to select the outer diameter of the backing tube in consideration of the difference in linear expansion coefficient between the backing tube and the cylindrical target material.

For example, a cylindrical target material made of tin-doped indium oxide (ITO) having a linear expansion coefficient at 20 ° C. of 7.2 × 10 ⁻⁶ / ° C. is used as a backing tube, and the linear expansion coefficient at 20 ° C. is 17. When using a product made of SOS304 of 3 × 10 ⁻⁶ / ° C., in the state where the cylindrical target material and the backing tube are combined, the width of the gap between them is preferably 0.3 mm to 3.0 mm, More preferably, the outer diameter of the backing tube is set to be 0.5 mm to 1.0 mm. If the width of the gap is less than 0.3 mm, the cylindrical target material may be broken due to the thermal expansion of the backing tube when a molten bonding material is injected. On the other hand, if the width of the gap exceeds 3.0 mm, it is difficult to join the cylindrical target material and the backing tube in a coaxial arrangement.

[Joint layer]
The bonding layer can be formed by injecting a bonding material into a gap between the cylindrical target material and the backing tube, and cooling and solidifying the bonding material.

  The bonding layer has an adhesive strength for firmly bonding the cylindrical target material and the backing tube, thermal conductivity capable of transferring heat generated during sputtering to the coolant flowing inside the backing tube, and discharge during sputtering. It is required to have the possible electrical conductivity. As a bonding material capable of forming such a bonding layer, for example, a low melting point solder mainly composed of indium, tin, or the like can be used.

(2) Cylindrical sputtering target The cylindrical sputtering target of this invention is obtained by the manufacturing method mentioned above, and is comprised from an at least 1 cylindrical target material, a backing tube, and a joining layer similarly to a prior art. Particularly, in the cylindrical sputtering target of the present invention, since the cylindrical target material of the present invention described above is used as the cylindrical target material, it has excellent roundness α ₁ and concentricity β _1. It can be evaluated that there is. For this reason, the cylindrical sputtering target of the present invention has almost no eccentricity, and when it is installed in a magnetron rotary cathode sputtering apparatus and sputtering is performed, peeling of the cylindrical target material, abnormal discharge, and abnormal film formation are suppressed. can do. Therefore, the cylindrical sputtering target of this invention can implement | achieve stably the high target usage efficiency which a cylindrical sputtering target has.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

Example 1
[Molding process]
Water, a binder, and a dispersing agent were added to a mixed powder composed of indium oxide powder and tin oxide powder to form a slurry, and then granulated powder was obtained by spray drying. Next, this granulated powder is filled into a mold comprising an upper lid made of silicon rubber, an outer frame made of soft rubber, and an inner frame made of hard plastic rubber, and a pressure of 294 MPa is applied by the CIP method to form a cylinder. A shaped ceramic compact was obtained.

[Baking process]
This cylindrical ceramic molded body was degreased by raising the temperature to 500 ° C. over 20 hours in an air atmosphere. After that, by switching to a pure oxygen atmosphere, raising the temperature to 1550 ° C. and holding at this temperature for 20 hours, firing is performed so that the cylindrical ceramic sintered body having a total length of 201.7 mm, an outer diameter of 155 mm, and an inner diameter of 131 mm Body 1 was obtained. The roundness α ₀ and the concentricity β ₀ of this cylindrical ceramic sintered body 1 were calculated. Specifically, measurement is performed at any eight locations using the outer diameter d of the cylindrical ceramic sintered body, the maximum value d _{0 (max)} and the minimum value d _{0 (min)} are obtained, and the above formula (a ) To calculate the roundness α ₀ . Further, the thickness t of the cylindrical ceramic sintered body is measured at any eight locations using a micrometer, and the maximum value t _{0 (max)} and the minimum value t _{0 (min)} are obtained. The concentricity β ₀ was calculated from b). As a result, it was confirmed that the roundness α ₀ of the cylindrical ceramic sintered body 1 obtained in Example 1 was 1.00 mm and the concentricity β ₀ was 0.80 mm.

[Processing process]
a) End Surface Grinding The cylindrical ceramic sintered body 1 obtained as described above has a large distortion, and stable chucking is impossible only with a scroll catch. For this reason, in Example 1, the cylindrical ceramic sintered body 1 is placed on the table 6 so that the one end face 2 is on the upper side and the other end face 3 is on the lower side. The four thickness gauges 7 (between the other end surface 3 and the table 6 are arranged so that the variation in the distance h ₁ from the surface of the table 6 to the one end surface is within 0.80 mm at eight positions on the circumference of the end surface. (Thickness: 0.10 mm to 0.60 mm) was inserted radially, and fixed by arranging fixed blocks 8 having a height of 100 mm on the four sides of the cylindrical ceramic sintered body 1. At this time, the thickness s _max of the thickest thickness gauge 7 was 0.60 mm.

  In this state, the one end face 2 was ground using a grindstone 9 having a grain size of # 140. Specifically, the grindstone 9 is rotated clockwise at a rotational speed of 1500 rpm, and the plunge processing as rough grinding is performed on the one end surface 2 in four times, and then the cylindrical ceramic sintered body 1 The traverse process was performed in four steps until the total length was 201.35 mm. At this time, the cut amount in rough grinding was adjusted to 20 μm, and the cut amount in finish grinding was adjusted to 5 μm. In addition, the amount of grinding in rough grinding was adjusted so that the amount of grinding in finishing was about 10 μm. After the end face 2 was ground, the cylindrical ceramic sintered body 1 was placed so that the other end face 3 was on the upper side, and fixed and ground in the same manner. The amount of grinding by end face grinding was adjusted to 0.70 mm by combining the one end face 2 and the other end face 3. When the perpendicularity γ and parallelism δ of the cylindrical ceramic sintered body 1 thus obtained were measured with a height gauge, the perpendicularity γ was 0.25 mm and the parallelism δ was 0.15 mm. confirmed.

b) Peripheral surface grinding After the end surface grinding, the one end surface 2 is bonded to the fixing jig 10 using a temporary fixing adhesive 12 (manufactured by Nikka Seiko Co., Ltd., Adfix) having a heat melting temperature of 120 ° C. Then, the cylindrical ceramic sintered body was fixed. At this time, the distance h ₂ to the surface of the fixing jig 10 was measured at eight locations on the circumference of the other end surface 3 of the cylindrical ceramic sintered body 1. It was confirmed that both were 201.0 mm. It was. After confirming that the cylindrical ceramic sintered body 1 was stably fixed, the outer peripheral surface 4 was ground using a cylindrical grinder (manufactured by Opto-Koki Co., Ltd., NVG).

  Specifically, as shown in FIG. 3, after using a grindstone 11 to cut a predetermined amount in the direction of arrow A, the grindstone 11 is moved in the direction of arrow B by the width, and similarly, a predetermined amount is cut. The operation was performed four times, and the entire outer peripheral surface 4 of the cylindrical ceramic sintered body 1 was plunge processed. Subsequently, using the grindstone 11, the operation of moving the grindstone 11 in the direction of the arrow B while cutting a predetermined amount in the direction of the arrow A was performed four times, and the entire outer peripheral surface 4 was traversed.

d) Inner peripheral surface grinding After the outer peripheral surface grinding, the cylindrical ceramic sintered body 1 is removed from the fixing jig 10 and the cylindrical ceramic sintered body 1 is fixed to the fixing jig (three-jaw scroll chuck) 13. Then, the inner peripheral surface 5 was ground by the same grinding method and grinding conditions as in the outer peripheral surface grinding using the inner surface grinding machine. After finishing the inner surface grinding, in order to completely remove the temporary fixing adhesive 12, the end surface 2 is ground by about 1 mm, a cylinder having a total length of 200 mm, an outer diameter of 151 mm, an inner diameter of 135 mm, and a wall thickness of 8 mm. A shaped target material was prepared.

[Evaluation of cylindrical target material]
The roundness α ₁ and the concentricity β ₁ of the cylindrical target material thus obtained were measured by the diameter method. Specifically, the outer diameter of the cylindrical target material is measured at any 8 locations, and the maximum value d _{1 (max)} and the minimum value d _{1 (min)} are obtained. The degree α ₁ was calculated. Further, the thickness of the cylindrical target material is measured at any eight locations using a micrometer, and the maximum value t _{1 (max)} and the minimum value t _{1 (min)} are obtained. From the above, the concentricity β ₁ was calculated. As a result, it was confirmed that the cylindrical target material obtained in Example 1 had a roundness α ₁ of 0.20 mm and a concentricity β ₁ of 0.20 mm.

(Example 2)
In the same manner as in Example 1, a cylindrical ceramic sintered body 1 was produced, and its roundness α ₀ and concentricity β ₀ were measured. As a result, it was confirmed that the roundness α ₀ of the cylindrical ceramic sintered body 1 obtained in Example 2 was 1.00 mm and the concentricity β ₀ was 0.50 mm.

In addition, the cylindrical ceramic sintered body 1 has one end surface 2 and the other end surface in the same manner as in Example 1 except that a three-jaw scroll chuck is used as the fixing jig 9 during outer peripheral surface grinding. 3, the outer peripheral surface 4 and the inner peripheral surface 5 were ground, the cylindrical target material was obtained, and the evaluation was performed. As a result, the cylindrical target material obtained in Example 2 was confirmed to have a roundness α ₁ of 0.20 mm and a concentricity β ₁ of 0.09 mm. Further, it was confirmed that the perpendicularity γ was 0.20 mm and the parallelism δ was 0.15 mm.

(Example 3)
With respect to the cylindrical ceramic sintered body 1 obtained in the same manner as in Example 2, the fixed position of the cylindrical ceramic sintered body 1 is set so that the variation in h ₂ is 0.30 mm when grinding the outer peripheral surface. Except having adjusted, it carried out similarly to Example 1, the 1 end surface 2, the other end surface 3, the outer peripheral surface 4, and the inner peripheral surface 5 were ground, the cylindrical target material was obtained, and the evaluation was performed. As a result, the cylindrical target material obtained in Example 2 was confirmed to have a roundness α ₁ of 0.30 mm and a concentricity β ₁ of 0.30 mm. Further, it was confirmed that the perpendicularity γ was 0.30 mm and the parallelism δ was 0.15 mm.

(Comparative Example 1)
In the same manner as in Example 2, a cylindrical ceramic sintered body 1 was produced, and its roundness α ₀ and concentricity β ₀ were measured. As a result, it was confirmed that the roundness α ₀ of the cylindrical ceramic sintered body 1 obtained in Comparative Example 1 was 1.00 mm and the concentricity β ₀ was 0.50 mm.

  After performing end face grinding in the same manner as in Example 1, inner peripheral face grinding was performed by an internal grinder. At this time, an attempt was made to chuck the cylindrical ceramic sintered body 1 with a three-jaw scroll chuck, but stable chucking could not be performed. For this reason, the cylindrical ceramic sintered body 1 was chucked by sandwiching cardboard between the three-jaw scroll chuck and the cylindrical ceramic sintered body 1, and the inner peripheral surface was ground.

  Subsequently, the outer peripheral surface was ground with a cylindrical grinder. At this time, an attempt was made to chuck the cylindrical ceramic sintered body 1 with a three-jaw scroll chuck, but stable chucking could not be performed. For this reason, the cylindrical ceramic sintered body 1 was chucked by sandwiching cardboard between the three-jaw scroll chuck and the cylindrical ceramic sintered body 1, and the outer peripheral surface was ground. However, since abnormal noise was generated, the outer peripheral surface grinding was interrupted at that time. When the cylindrical ceramic sintered body 1 was observed in this state, it was confirmed that a crack was generated at the contact portion with the three-jaw scroll chuck. This is presumably because, in Comparative Example 1, the inner peripheral surface grinding was performed before the outer peripheral surface grinding, so that a local force acted on the cylindrical ceramic sintered body 1 during the outer peripheral surface grinding.

(Comparative Example 2)
In the same manner as in Example 2, a cylindrical ceramic sintered body 1 was produced, and its roundness α ₀ and concentricity β ₀ were measured. As a result, it was confirmed that the roundness α ₀ of the cylindrical ceramic sintered body 1 obtained in Comparative Example 1 was 1.00 mm and the concentricity β ₀ was 0.50 mm.

Next, the cylindrical ceramic sintered body 1 was fixed by bonding the one end surface 2 to the fixing jig 10 using the temporary fixing adhesive 12, and the outer peripheral surface 4 was ground. At this time, the distance h ₂ to the surface of the fixing jig 9 is measured at eight positions on the circumference of the other end surface 3 of the cylindrical ceramic sintered body 1 so that the variation is within 0.20 mm. It was adjusted. After the outer peripheral surface grinding is completed, the cylindrical ceramic sintered body 1 is removed from the fixing jig 10, and the cylindrical ceramic sintered body 1 is fixed to the fixing jig (three-jaw scroll chuck) 13. Using, the inner peripheral surface 5 was ground. Finally, in the same manner as in Example 1, one end surface 2 and the other end surface 3 of the cylindrical ceramic sintered body 1 were ground to obtain a cylindrical target material.

The cylindrical target material thus obtained was confirmed to have a roundness α ₁ of 0.50 mm and a concentricity β ₁ of 0.60 mm. Further, it was confirmed that the perpendicularity γ was 0.65 mm and the parallelism δ was 0.15 mm. In Comparative Example 2, the reason why the roundness α ₁ and the concentricity β ₁ are large is that grinding in the outer peripheral surface grinding and inner peripheral surface grinding is because the end face grinding was not performed first. This is probably because the amount could not be controlled within an appropriate range.

(Comparative Example 3)
Except that one end surface 2, the other end surface 3, the outer peripheral surface 4 and the inner peripheral surface 5 of the cylindrical ceramic sintered body 1 obtained in the same manner as in Example 2 were cut by a lathe, the same as in Example 1. A cylindrical target material was obtained. When the surface of the cylindrical target material thus obtained was visually observed, it was confirmed that many chips and cracks were generated. For this reason, in the comparative example 3, the cylindrical target material was not evaluated.

(Comparative Example 4)
Three cylindrical ceramic sintered bodies 1 obtained in the same manner as in Example 2 are provided between the other end face 3 and the table 6 so that the variation in h ₁ is 0.80 mm during end face grinding. The thickness s _max of the thickest thickness gauge 7 was 1.00 mm, and the grinding amount of the one end face 2 and the other end face 3 was 1.10 mm in total. Except for the above, in the same manner as in Example 1, the one end surface 2, the other end surface 3, the outer peripheral surface 4 and the inner peripheral surface 5 were ground to obtain a cylindrical target material, which was evaluated. As a result, the cylindrical target material obtained in Example 2 was confirmed to have a roundness α ₁ of 0.50 mm and a concentricity β ₁ of 0.80 mm. Further, it was confirmed that the perpendicularity γ was 0.90 mm and the parallelism δ was 0.15 mm.

(Comparative Example 5)
The cylindrical ceramic sintered body 1 obtained in the same manner as in Example 2 was fixed at a fixed position of the cylindrical ceramic sintered body 1 so that the variation in h ₂ was 0.40 mm during outer peripheral surface grinding. Except having adjusted, it carried out similarly to Example 1, the 1 end surface 2, the other end surface 3, the outer peripheral surface 4, and the inner peripheral surface 5 were ground, the cylindrical target material was obtained, and the evaluation was performed. As a result, it was confirmed that the cylindrical target material obtained in Example 2 had a roundness α ₁ of 0.50 mm and a concentricity β ₁ of 0.60 mm. Further, it was confirmed that the perpendicularity γ was 0.55 mm and the parallelism δ was 0.15 mm.

(Example 4 and Comparative Example 6)
Five cylindrical target materials obtained in Examples 1 to 3 and Comparative Examples 2, 4 and 5 were prepared, respectively, and a bonding agent made of indium metal on a backing tube made of SUS304 having an outer diameter of 150 mm and an overall length of 1100 mm. The cylindrical sputtering target was produced by bonding using At this time, the cylindrical sputtering target was not cracked or chipped.

  This cylindrical sputtering target was attached to a magnetron rotary cathode sputtering apparatus, and sputtering was performed for 4 hours. After completion of sputtering, the cylindrical sputtering target was visually observed for peeling, abnormal discharge, and film formation. The results are shown in Table 2.

DESCRIPTION OF SYMBOLS 1 Cylindrical ceramic sintered body 2 One end surface 3 Other end surface 4 Outer peripheral surface 5 Inner peripheral surface 6 Table 7 Cygness gauge 8 Fixed block 9 Grinding wheel (surface grinder)
10 Fixing jig (cylindrical grinding machine)
11 Grinding wheel (cylindrical grinding machine)
12 Adhesive for temporary fixing 13 Fixing jig (Internal grinding machine)
14 Grinding wheel (internal grinding machine)

Claims (12)

A molding process for forming a cylindrical ceramic molded body by cold isostatic pressing;
Firing the cylindrical ceramic molded body to obtain a cylindrical ceramic sintered body; and
After grinding one end surface and the other end surface of the cylindrical ceramic sintered body with a surface grinder having a table, the outer peripheral surface of the cylindrical ceramic sintered body is ground with a cylindrical grinder, and then the cylinder A machining process in which the inner peripheral surface of the ceramic sintered body is ground by an internal grinding machine;
With
In the grinding by the surface grinder, the cylindrical ceramic sintered body is placed on the table so that the one end surface is on the upper side, and the variation in the distance from the surface of the table to the one end surface is zero. After controlling to within 80 mm, fix to the table, and grind the one end surface.
Manufacturing method of cylindrical target material.   The manufacturing of the cylindrical target material according to claim 1, wherein, in the grinding process by the cylindrical grinder, the cylindrical ceramic sintered body is fixed to a fixing jig of the cylindrical grinder via a temporary fixing adhesive. Method.   In grinding by the cylindrical grinder, an adhesive layer is formed by applying the temporary fixing adhesive to the surface of the fixing jig, and the other end surface of the cylindrical ceramic sintered body is formed on the adhesive layer. The cylindrical ceramic sintered body is fixed to the fixing jig after controlling so that a variation in distance from the surface of the fixing jig to the one end surface is within 0.30 mm. The manufacturing method of the cylindrical target material of Claim 2 which grinds an outer peripheral surface.   In grinding by the surface grinder, when grinding the one end face, at least one thickness gauge is inserted between the table and the other end face, and the distance from the table surface to the one end face is set. The manufacturing method of the cylindrical target material in any one of Claims 1-3 controlled so that dispersion | variation becomes less than 0.80 mm.   In grinding by the surface grinder, the maximum amount of the thicknesses of the at least one thickness gauge inserted between the table and the other end surface is the total amount of grinding of the one end surface and the other end surface. The manufacturing method of the cylindrical target material of Claim 4 made into the quantity which added 0.10 mm-0.20 mm to.   The manufacturing method of the cylindrical target material in any one of Claims 1-5 whose roundness of the said cylindrical ceramic sintered compact after the said baking process is 0.50 mm or more.   The method for producing a cylindrical target material according to any one of claims 1 to 6, wherein the grinding process is performed by dividing into rough grinding with a cut amount of 1 µm to 30 µm and finish grinding with a cut amount of 10 µm or less.   The method for producing a cylindrical target material according to any one of claims 1 to 7, wherein the roundness of the obtained cylindrical target material is 0.30 mm or less and the concentricity is 0.30 mm or less.   The method for producing a cylindrical target material according to claim 8, wherein an outer diameter of the obtained cylindrical target material is 80 mm to 200 mm, an inner diameter is 40 mm to 190 mm, a thickness is 5 mm to 20 mm, and a total length is 50 mm to 500 mm. .   After a single backing tube is coaxially disposed in the hollow portion of at least one cylindrical target material, a bonding layer is formed in a gap between the cylindrical target material and the backing tube, and the cylindrical target material and the cylindrical target material It is a manufacturing method of the cylindrical sputtering target which joins a backing tube, Comprising: As the said cylindrical target material, the cylindrical target material obtained by the manufacturing method of the cylindrical target material of Claim 8 or 9 is used. The manufacturing method of a cylindrical sputtering target. A cylindrical target material made of at least one cylindrical ceramic sintered body, a single backing tube disposed coaxially in a hollow portion of the cylindrical target material, and a gap between the target material and the backing tube A cylindrical sputtering target consisting of a bonding layer formed on
The cylindrical target material has an outer diameter of 80 mm to 200 mm, an inner diameter of 40 mm to 190 mm, a wall thickness of 5 mm to 20 mm, a total length of 50 mm to 500 mm, and a roundness of 0.30 mm or less. And the concentricity is 0.30 mm or less,
Cylindrical sputtering target. The cylindrical sputtering according to claim 11 , wherein the perpendicularity of the one end face and the other end face of the cylindrical ceramic sintered body is 0.30 mm or less, and the parallelism of the one end face and the other end face is 0.20 mm or less. target.

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