JP6678157B2 - Method for manufacturing cylindrical target material and method for manufacturing cylindrical sputtering target - Google Patents

Description

The disclosed embodiments relates to a method of manufacturing a manufacturing method and a cylindrical sputtering target of the cylindrical target material.

  2. Description of the Related Art A magnetron-type rotary cathode sputtering apparatus that has a magnetic field generator inside a cylindrical target material and performs sputtering while rotating the target material while cooling the target material from the inside is known. In such a sputtering apparatus, the entire outer peripheral surface of the target material becomes erosion and is uniformly cut. For this reason, the use efficiency of the target material is 20 to 30% in the conventional flat-plate type magnetron sputtering apparatus, while the use efficiency of the target material is remarkably high at 70% or more in the magnetron rotary cathode sputtering apparatus.

  In addition, a magnetron-type rotary cathode sputtering device can perform a sputtering while rotating a cylindrical target material, so that a larger power can be applied per unit area than a flat-plate type magnetron sputtering device. As a result, the production efficiency during film formation can be improved.

  In recent years, glass substrates used in flat panel displays and solar cells have been increased in size. In order to efficiently form a thin film on the enlarged substrate, for example, a long cylindrical sputtering target exceeding 3 m has been used. Is needed. Accordingly, it is required that the length of the cylindrical target material constituting the cylindrical sputtering target be further increased.

  As a method of increasing the length of a ceramic cylindrical target material, a method of stacking and using a plurality of cylindrical target materials is known (for example, see Patent Document 1). However, there is still a divided portion between the cylindrical target materials to prevent collision cracking due to thermal expansion of the target material, and arcing and particles are generated due to the divided portion. In order to suppress the generation of such arcing and particles, it is necessary to eliminate the divided portions or to increase the length of each of the cylindrical target materials stacked and used to reduce the number of divided portions.

  On the other hand, when the length of the cylindrical target material is increased, distortion tends to occur during firing in the manufacturing process. In order to obtain a cylindrical target material having a desired dimension from a greatly warped calcined body, it is necessary to calcine a compact that has been formed to have a thickness greater than the desired dimension in advance, and to perform processing such as cutting. Therefore, the cost increases. Furthermore, if the fired body obtained by firing is distorted beyond the limit that can be processed, even if a thick molded body is used, it cannot be processed to the desired dimensions in the post-process, and cannot be used as a target material. I will. That is, in the production of a particularly long cylindrical target material, the distortion generated during firing leads to an increase in the loss of raw materials due to processing, the production of a fired body that cannot be used as a cylindrical target material, and the yield is greatly reduced.

  Patent Literatures 2 and 3 disclose a method of suppressing a distortion of a cross-sectional shape by firing a cylindrical ceramic molded body on a member having a shrinkage rate equivalent to that of the molded body.

JP 2010-100930 A JP-A-5-70244 JP-A-6-279092

  However, in the above-described prior art, there is still room for further improvement because distortion is inevitable during firing when producing a long cylindrical target material having a length of 500 mm or more.

One mode of the embodiment is made in view of the above, and has a good yield of raw materials used by suppressing the occurrence of distortion during firing, and a method of manufacturing a cylindrical target material that can be manufactured at low cost. An object of the present invention is to provide a method for manufacturing a cylindrical sputtering target.

  The method for manufacturing a cylindrical target material according to the embodiment includes a forming step and a firing step. In the forming step, a ceramic formed body formed into a cylindrical shape is produced. In the firing step, the outer peripheral surface of the formed body is supported on the receiving surface of the setter along the length direction, and the formed body is fired in a posture inclined with respect to a horizontal plane.

According to an aspect of the embodiment, provided with a high yield of the raw materials to be used often, a manufacturing method and a cylindrical sputtering target manufacturing method of the cylindrical target material that may be inexpensively produced by suppressing occurrence of distortion during sintering can do.

FIG. 1A is a schematic diagram illustrating an outline of a configuration of a cylindrical sputtering target. FIG. 1B is a sectional view taken along the line A-A ′ of FIG. 1A. FIG. 2A is an explanatory diagram illustrating an outline of a method for manufacturing a cylindrical target material according to the embodiment. FIG. 2B is a sectional view taken along the line B-B ′ of FIG. 2A. FIG. 3A is a diagram for explaining the lengthwise distortion of the primary fired body. FIG. 3B is a diagram for explaining radial distortion of the primary fired body. FIG. 4A is an explanatory diagram illustrating an outline of a method for manufacturing a cylindrical target material according to the embodiment. FIG. 4B is an explanatory diagram illustrating an outline of a method for manufacturing a cylindrical target material according to the embodiment. FIG. 4C is a cross-sectional view taken along line C-C ′ of FIG. 4B. FIG. 5A is an explanatory diagram illustrating an outline of a modification of the method for manufacturing a cylindrical target material according to the embodiment. FIG. 5B is an explanatory diagram illustrating an outline of a modification of the method for manufacturing a cylindrical target material according to the embodiment. FIG. 6 is a flowchart illustrating an example of a method for manufacturing a cylindrical target material according to the embodiment.

Hereinafter, with reference to the accompanying drawings, an embodiment of a manufacturing method and a cylindrical sputtering target manufacturing method of the cylindrical target material disclosed in the present application in detail. The present invention is not limited by the embodiments described below.

  First, a cylindrical sputtering target to which a cylindrical target material manufactured by the method for manufacturing a cylindrical target material according to the embodiment can be applied will be described with reference to FIGS. 1A and 1B.

  FIG. 1A is a schematic diagram illustrating an outline of a configuration of a cylindrical sputtering target according to an embodiment, and FIG. 1B is a cross-sectional view along A-A ′ in FIG. 1A. 1A and 1B show a three-dimensional orthogonal coordinate system including a Z-axis in which a vertically upward direction is a positive direction and a vertically downward direction is a negative direction. Such an orthogonal coordinate system may be shown in other drawings used in the following description.

  As shown in FIGS. 1A and 1B, a cylindrical sputtering target (hereinafter, referred to as a “cylindrical target”) 1 includes a cylindrical target material 2 and a backing tube 3. The cylindrical target material 2 and the backing tube 3 are joined by a joining material 4.

  Here, the cylindrical target material 2 is formed of a ceramic material processed into a substantially cylindrical shape. Hereinafter, an example of a method for manufacturing the cylindrical target material 2 will be described.

  The method for producing the cylindrical target material 2 includes a granulation step of granulating a slurry containing a ceramic raw material powder and an organic additive to produce granules, and molding the granules to produce a cylindrical molded body. And a molding step. In addition, the manufacturing method of a molded object is not limited to the above-mentioned method, and may be any method.

  Further, the method for manufacturing the cylindrical target material 2 according to the embodiment further includes a firing step of firing the molded body. In the firing step, the outer peripheral surface of the molded body is supported on the receiving surface of the setter along the length direction, and by firing the molded body in a posture inclined with respect to a horizontal plane, distortion generated during firing of the molded body is reduced. . Hereinafter, an example of such a firing step will be described with reference to FIGS. 2A and 2B.

  FIG. 2A is an explanatory diagram showing an outline of a firing step in the method of manufacturing the cylindrical target material 2 according to the embodiment, and FIG. 2B is a cross-sectional view taken along the line B-B ′ of FIG. 2A.

  As shown in FIG. 2A, the substantially flat setter 5, which is a firing jig, is arranged so that the receiving surface 51 side faces upward and is inclined with respect to the horizontal plane 7. The molded body 12 is arranged so that the receiving surface 51 and the length direction of the molded body 12 are substantially parallel. Thus, the molded body 12 is fired in a posture in which the outer peripheral surface 121 is supported by the receiving surface 51 along the length direction of the molded body 12 and is inclined by the angle θ1 with respect to the horizontal plane 7. The details of the angle θ1 will be described later.

  The above-described molded body 12 has a lower density than a fired body obtained by firing. For this reason, the molded body 12 is made thicker than the dimension designed in advance as the cylindrical target material 2, and the dimension in the length direction is longer than the entire length of the cylindrical target material 2. The density of the molded body 12 is about 60 to 70% of the density of the cylindrical target material 2 obtained by processing the fired body, and shrinkage of about 20% in dimension during firing, that is, linear shrinkage occurs.

  In the firing step, firing is usually performed in a state where the molded body 12 is upright. However, in this case, for example, there is a difference in molding density between locations of the molded body 12 in the firing furnace, a difference in temperature between locations in the firing furnace during firing, and a firing in which the molded body 12 is placed for firing. Distortion in the longitudinal direction is likely to occur in the fired body due to the inclination of the molded body 12 caused by the inclination of the jig, the setter, the hearth, and the like.

  Further, when the compact 12 is laid on its side so that the length direction of the compact 12 is substantially horizontal and fired, the above-described distortion in the longitudinal direction of the compact 12 is reduced, but the softened compact 12 is reduced. Twelve weights tend to cause radial distortion. For this reason, in the fired body obtained by sintering the molded body 12 sideways, distortion such as a difference in the outer diameter and / or inner diameter of each portion is likely to occur. Here, the “strain in the length direction” and the “strain in the radial direction” of the primary fired body will be described with reference to FIGS. 3A and 3B, respectively.

  First, the "strain in the length direction" of the primary fired body will be described. FIG. 3A is a diagram for explaining the lengthwise distortion of the primary fired body. As shown in FIG. 3A, a primary fired body having an ideal shape without distortion imagined as a cylindrical shape is formed so that both end faces are parallel to the XZ plane, and the length direction is parallel to the Y axis. It is arranged on a three-dimensional rectangular coordinate system. At this time, in the rectangular external shape L of the imaginary primary fired body viewed from the X-axis direction, at least a part of the long side extending in the length direction of the primary fired body is shifted from the state parallel to the Y-axis by X Deformation of the external shape L so as to warp or bend toward the axis side and / or Z-axis side is referred to as “distortion in the length direction”, and the degree of the deformation is referred to as “distortion in the length direction”. The appearance shape Ld is an example in which the length direction of the primary fired body is distorted in the Z-axis direction.

  Next, "radial distortion" of the primary fired body will be described. FIG. 3B is a diagram for explaining radial distortion of the primary fired body. As shown in FIG. 3B, a primary fired body having an ideal shape without distortion, which is imagined as a cylindrical shape, is arranged on a three-dimensional orthogonal coordinate system as in FIG. 3A. At this time, in the annular appearance shape R of the virtual primary fired body viewed from the Y-axis direction, at least a part of the outer diameter and / or inner diameter receives an external force on the X-axis side and / or the Z-axis side. Deformation is referred to as “radial distortion”, and the degree of the deformation is referred to as “radial distortion”. Further, among the “radial distortions”, the distortion of the outer diameter in the radial direction may be defined as “outer diameter distortion”, and the distortion of the inner diameter in the radial direction may be distinguished as “inner diameter distortion”. The external shape Rd is an example in which the outer diameter and the inner diameter are distorted such that the one end face or the cross-sectional shape of the primary fired body is compressed in the Z-axis direction.

  On the other hand, in the method for manufacturing the cylindrical target material 2 according to the embodiment, the molded body 12 is fired in a state inclined with respect to the horizontal plane 7. When the compact 12 is inclined with respect to the horizontal plane 7 so that the width of the compact 12 in the vertical direction, that is, the dimension of the compact 12 extending in the Z-axis direction shown in FIG. It is larger than. Therefore, according to the method for manufacturing the cylindrical target material 2 according to the embodiment, a fired body in which the deformation of the molded body 12 in the vertical direction is suppressed can be obtained.

  In the method for manufacturing the cylindrical target material 2 according to the embodiment, the outer peripheral surface 121 of the molded body 12 is supported on the receiving surface 51 of the setter 5 along the length direction and fired. Since the molded body 12 is supported on the receiving surface 51 along the length direction, the load of the molded body 12 is substantially uniformly deposited on the setter 5 over the length direction. For this reason, according to the manufacturing method of the cylindrical target material 2 according to the embodiment, the shaped body 12 has a shape along the setter 5 at the time of firing, and the length direction is smaller than the case where the shaped body 12 is erected and fired. A fired body with reduced distortion is obtained. In addition, due to the properties of the cylindrical molded body, for example, when the end of the molded body 12 becomes convex, the molded body 12 may not be placed as described above. In this case, in order to place and fire the formed body 12 as shown in FIG. 2A, a process such as cutting an end of the formed body 12 may be performed in advance.

  Here, the angle θ1 indicates the degree of inclination of the molded body 12 with respect to the horizontal plane 7, and takes a value from 0 ° to 90 °. The angle θ1 (hereinafter, referred to as “inclination angle θ1”) is preferably 30 ° or more and 85 ° or less, more preferably 40 ° or more and 85 ° or less, and further preferably 60 ° or more and 75 ° or less. If the inclination angle θ1 is less than 30 °, the deformation in the vertical direction may not be sufficiently suppressed, for example, depending on the length of the molded body 12. If the inclination angle θ1 exceeds 85 °, for example, the molded body 12 may not be able to be sufficiently supported on the receiving surface 51 in some cases.

  In addition, a bottom plate 6 on which the bottom surface of the molded body 12 is placed may be disposed on the end surface (bottom surface) of the molded body 12 leaned against the setter 5 on the side of the lower end surface (bottom surface). Good. As shown in FIG. 2A, when the compact 12 is placed on the mounting surface 61 of the bottom plate 6 disposed at an angle of 90 ° with respect to the setter 5, the compact 12 is supported by the bottom surface 123 of the compact 12. be able to. For this reason, for example, when only a part of the bottom surface 123 side of the molded body 12 comes into contact with the hearth or the like, the load of the molded body 12 is concentrated on a very small part of the molded body 12, and cracks and deformation occur. Failure can be prevented or suppressed.

  Here, the setter 5 is preferably flat, but the shape of the setter 5 is not limited as long as at least the receiving surface 51 of the molded body 12 is formed to be substantially flat. As the material of the setter 5, ceramics having high heat resistance such as alumina, magnesia, and zirconia are preferable. Further, a high-purity alumina powder may be attached to a portion of the receiving surface 51 of the setter 5 where the molded body 12 contacts.

  Further, there is no particular limitation on the method of maintaining the inclination of the setter 5 and / or the bottom plate 6 in order to appropriately maintain the inclination angle θ1 of the molded body 12 with respect to the horizontal plane 7. For example, there is a method of leaning the setter 5 and / or the bottom plate 6 on the refractory bricks stacked to have a predetermined height, but is not limited thereto. It is preferable that the inclination angle θ1 of the molded body 12 does not change before and after firing, or is maintained within the above-described predetermined range until cooling after firing is completed.

  Here, the manufacturing method of the cylindrical target material 2 according to the embodiment is applied when the entire length of the molded body 12 is preferably 500 mm or more, more preferably 600 mm or more, further preferably 750 mm or more, and most preferably 1000 mm or more. You. When the entire length of the molded body 12 is less than 500 mm, the distortion caused by firing of the molded body 12 is small even if the present manufacturing method is not applied. However, since warpage and distortion are reduced even for a molded body 12 having a total length of less than 500 mm, the present manufacturing method is applicable to a molded body 12 having any total length. The upper limit of the overall length of the molded body 12 is not particularly limited, but the cylindrical target material 2 obtained by sintering the molded body 12 is usually set at 4000 mm or less because the cylindrical target material 2 is installed inside the sputtering apparatus. is there.

Examples of the cylindrical target material 2 obtained by processing the fired body include oxides containing at least one of In, Zn, Al, Ga, Zr, Ti, Sn, Mg, and Si. Can be. Specifically, ITO (In ₂ O ₃ —SnO ₂ ) having a Sn content of 1 to 10% by mass in terms of SnO ₂ , and an Al content of 0.1 to 5% by mass in terms of Al ₂ O _{3 AZO (Al} 2 O 3 -ZnO) is 10 to 60 wt% in the content of in is _in 2 _{O 3} in terms of 10 to 60 mass% content of Ga is in terms _{of Ga} 2 _{O 3,} the content of Zn Is IGZO (In ₂ O ₃ —Ga ₂ O ₃ —ZnO) in terms of ZnO and IZO (In ₂ O ₃ —ZnO) in which the content of Zn is 1 to 15% by mass in terms of ZnO. Examples of compositions having such a composition can be given, but the present invention is not limited thereto. The processing of the fired body will be described later.

  When the cylindrical target material 2 to be manufactured is ITO, the firing temperature of the molded body 12 is preferably 1500 ° C to 1700 ° C, more preferably 1500 ° C to 1650 ° C, and further preferably 1500 ° C to 1600 ° C. ° C. When the cylindrical target material 2 to be manufactured is AZO, the firing temperature of the molded body 12 is preferably 1300 ° C to 1500 ° C, more preferably 1300 ° C to 1450 ° C, and further preferably 1350 ° C to 1450 ° C. ° C. When the cylindrical target material 2 to be manufactured is IGZO, the firing temperature of the molded body 12 is preferably 1350 ° C to 1550 ° C, more preferably 1400 ° C to 1500 ° C, and further preferably 1400 ° C to 1450 ° C. ° C. When the ceramic target material 2 to be manufactured is IZO, the firing temperature of the molded body 12 is preferably 1350 ° C to 1550 ° C, more preferably 1400 ° C to 1500 ° C, and still more preferably 1400 ° C to 1450 ° C. ° C. If the firing temperature is too low, the density of the fired body may not be sufficiently increased. On the other hand, if the sintering temperature is too high, the sintered structure of the molded body 12 is enlarged and easily cracked.

  The rate of temperature rise of the molded body 12 is preferably 50 ° C / h to 500 ° C / h. If the heating temperature is less than 50 ° C./h, the time required to reach the firing temperature becomes longer, and the working time becomes longer. On the other hand, if the temperature rise temperature exceeds 500 ° C./h, the temperature difference between the portions of the molded body 12 increases, and cracks are likely to occur.

  Further, the holding time at the firing temperature in the firing step is preferably 3 to 30 hours, more preferably 5 to 20 hours, and further preferably 8 to 16 hours. As the firing time is longer, the density of the target material is more likely to be increased. However, if the firing time is too long, the sintered structure of the fired body is enlarged and easily cracked.

  In the above-described embodiment, an example in which the bottom surface 123 of the molded body 12 is directly mounted on the mounting surface 61 of the bottom plate 6 has been described, but the shrinkage rate is approximately the same as that of the molded body 12 on the bottom plate 6. A common ground may be arranged. By arranging such a co-base, for example, distortion of the shape on the bottom surface 123 side of the molded body 12 can be further suppressed. In addition, it is preferable to use what has the same composition as the molded body 12 and is formed into an unfired sheet or flat plate. Thereby, the shrinkage and expansion accompanying the temperature change in the molded body 12 and the co-base body become almost the same, and the distortion of the molded body 12 can be suppressed. However, the composition of the core material is not limited to the above as long as the shrinkage and expansion due to the temperature change are substantially equal to those of the molded body 12.

  Next, a method for manufacturing the cylindrical target material 2 according to the embodiment will be further described. The method for manufacturing the cylindrical target material 2 according to the embodiment further includes a finishing step of finishing the fired body. In the processing method in this step, for example, first, a fired body is set on a cylindrical grinder, and the outer peripheral surface side is processed. Next, the inner peripheral surface side is processed with reference to the outer peripheral surface of the fired body. Finally, processing of the outer peripheral surface side of the fired body is performed again to grind to a target dimension. Processing in the length direction can be performed by cutting and / or grinding. By such finishing, a cylindrical target material 2 having a desired dimension is manufactured. The processing method is not limited as long as the cylindrical target material 2 having the same processing accuracy can be manufactured.

  Next, the cylindrical target material 2 obtained by the method for manufacturing the cylindrical target material 2 according to the embodiment will be further described. The relative density of the cylindrical target material 2 is preferably 95% or more, more preferably 98% or more, and further preferably 99% or more. When the relative density of the cylindrical target material 2 is 95% or more, cracking of the cylindrical target material 2 due to, for example, thermal expansion during sputtering can be prevented or suppressed. Further, particles, nodules and arcing generated by sputtering can be reduced, and a thin film having good film quality can be obtained. Here, a method for measuring the relative density of the cylindrical target material 2 will be described below.

The relative density of the cylindrical target material 2 is measured based on the Archimedes method. Specifically, the airborne weight of the cylindrical target material 2 is divided by the volume (= weight of water in the cylindrical target material 2 / water specific gravity at the measurement temperature) to obtain a theoretical density ρ (g / cm) based on the following equation (X). ³ ) The value of percentage relative to the above is defined as a relative density (unit:%).

In the above formula (X), C _{1 to} C _i each indicate the content (% by mass) of the constituent material constituting the cylindrical target material 2, and ρ _{1 to} ρ _i are the respective components corresponding to C _{1 to} C _i Indicates the density of the substance (g / cm ³ ).

  Next, returning to FIG. 1A and FIG. 2B, the cylindrical target 1 using the cylindrical target material 2 obtained by the method for manufacturing the cylindrical target material 2 according to the embodiment will be further described. As the backing tube 3, a conventionally used one can be appropriately selected and used. As such a backing tube 3, for example, stainless steel, titanium, a titanium alloy, or the like can be used, but the present invention is not limited thereto.

  Further, as the joining material 4, a conventionally used material can be appropriately selected, and the cylindrical target material 2 and the backing tube 3 can be joined by the same method as in the related art. Examples of such a bonding material 4 include, but are not limited to, indium and an indium-tin alloy.

  Although FIG. 1A shows an example in which the cylindrical target 1 has one cylindrical target material 2 bonded to the outside of one backing tube 3, the present invention is not limited to this. For example, one obtained by joining two or more cylindrical target materials 2 on the same axis outside one or two or more backing tubes 3 may be used as the cylindrical target 1. When a plurality of cylindrical target materials 2 are joined side by side, the gap between adjacent cylindrical target materials 2, that is, the length of the divided portion is preferably 0.05 to 0.5 mm. Arcing is less likely to occur during sputtering as the length of the divided portion is shorter, but if the length of the divided portion is less than 0.05 mm, the cylindrical target materials 2 may collide with each other due to thermal expansion during the bonding process or sputtering and may be broken. is there.

  In the embodiment described above, the example in which the compact 12 is leaned against the receiving portion 51 of the flat-plate setter 5 in the firing step and fired is described. However, the present invention is not limited to this example. Hereinafter, a modification of the firing step will be described with reference to FIGS. 4A to 4C.

  FIG. 4A is an explanatory diagram illustrating an outline of a configuration of a V-shaped setter 8 that can be applied instead of the setter 5 in the method of manufacturing the cylindrical target material 2 according to the embodiment. FIG. 4B is an explanatory diagram showing an outline of a firing step in the method of manufacturing the cylindrical target material 2 according to the embodiment, and FIG. 4C is a cross-sectional view taken along line C-C ′ of FIG. 4B.

  As shown in FIGS. 4A to 4C, the embodiment is the same as the embodiment described with reference to FIGS. 2A and 2B, including firing conditions and the like, except that firing is performed using a V-shaped setter 8 instead of the setter 5. . The same members as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof may be omitted or may be limited to a simple description.

  A V-shaped setter 8 which is an example of a firing jig includes a receiving surface 81 formed in a V-shaped cross section. The receiving surface 81 includes receiving surfaces 81a and 81b facing each other at a predetermined angle. The V-shaped setter 8 includes a trough 83 formed along the intersection of the receiving surfaces 81a and 81b, and a crest 82 formed to face the trough 83 at a predetermined interval. They are formed to have substantially the same thickness.

  As shown in FIG. 4B and FIG. 4C, the V-shaped setter 8 has the crest 82 side down, that is, the receiving surface 81 side up, and the crest 82 and the valley 83 are inclined by the inclination angle θ1 with respect to the horizontal plane 7. It is arranged to be. The molded body 12 is arranged such that the inclination direction of the receiving surfaces 81a and 81b is substantially perpendicular to the length direction of the molded body 12. Accordingly, the molded body 12 is fired in a posture in which the outer peripheral surface 121 is supported by the receiving surfaces 81a and 81b along the length direction of the molded body 12, and is inclined by the inclination angle θ1 with respect to the horizontal plane 7. .

  Here, comparing FIG. 2B and FIG. 4C, in FIG. 2B, the outer peripheral surface 121 of the molded body 12 is in contact with the receiving surface 51 of the setter 5 at one place. On the other hand, in FIG. 4C, the outer peripheral surface 121 of the molded body 12 comes into contact with the receiving surfaces 81a and 81b of the V-shaped setter 8 at one position, that is, at two positions as the entire receiving surface 81. . For this reason, according to the present embodiment in which the V-shaped setter 8 is applied as the firing jig, the load applied by the compact 12 to the V-shaped setter 8 is dispersed as compared with the case where the setter 5 is applied, and the molding during firing is performed. The occurrence of cracks in the body 12 is further reduced. In addition, since the molded body 12 is in contact with the molded body 12 at two locations, the length direction of the molded body 12 is always maintained substantially parallel to the direction along the valley 83 even if the molded body 12 shrinks during firing. Therefore, the occurrence of distortion in the obtained fired body is further reduced.

  Here, similarly to the setter 5, the V-shaped setter 8 is preferably made of a highly heat-resistant ceramic such as alumina, magnesia, and zirconia. In addition, a powder made of high-purity alumina may be attached to a portion of the V-shaped setter 8 where the molded body 12 contacts. The angle θ2 formed between the receiving surfaces 81a and 81b can be changed according to the outer diameter and mass of the molded body 12, the firing temperature, the firing time, and the like. This angle θ2 is preferably from 25 ° to 80 °, more preferably from 45 ° to 70 °. If θ2 is less than 25 ° or more than 80 °, radial distortion of the molded body 12 is likely to occur. In the embodiment described with reference to FIGS. 4A to 4C, the thickness of the V-shaped setter 8 has been described as being substantially the same throughout, but the shape of the receiving surface 81 with which the molded body 12 abuts is substantially the same. For example, the shapes of the peaks 82 and the valleys 83 where the molded body 12 does not contact are not limited to those described above.

  For example, as shown in FIG. 5A, it has a receiving surface 101 composed of receiving surfaces 10 a and 10 b and a valley 103 formed to include the intersection of the receiving surfaces 10 a and 10 b, but has a shape corresponding to the peak 82. The setter 10 not used can be applied as a firing jig instead of the V-shaped setter 8.

  Further, as shown in FIG. 5B, the setter 11 having the receiving surface 111 composed of the receiving surfaces 11 a and 11 b and having the arc-shaped valley 113 in cross section can also be applied as a firing jig instead of the V-shaped setter 8.

  Next, a method for manufacturing the cylindrical target material 2 according to the embodiment will be described with reference to FIG. FIG. 6 is a flowchart illustrating an example of a processing procedure for manufacturing the cylindrical target material 2 according to the embodiment.

  As shown in FIG. 6, first, a molded body 12 formed into a cylindrical shape is manufactured (Step S11). Next, the outer peripheral surface 121 of the molded body 12 is supported by the receiving surface 51 or 81 of the setter 5 or the V-shaped setter 8 along the length direction, and the molded body 12 is baked in a posture inclined with respect to the horizontal plane 7 and deformed. Is generated (Step S12).

  Subsequently, the outer peripheral surface and the inner peripheral surface of the fired body are ground and both end surfaces are cut and / or ground (step S13). Through the above steps, a cylindrical target material 2 having desired dimensions is manufactured.

[Example 1]
10 mass% of SnO ₂ powder having a specific surface area (BET specific surface area) of 5 m ² / g measured by the BET (Brunauer-Emmett-Teller) method, and In ₂ O ₃ powder 90 having a BET specific surface area of 5 m ² / g % By mass and mixed in a ball mill with zirconia balls in a pot to prepare a raw material powder. The BET specific surface area was measured using Monosorb (trade name) manufactured by Yuasa Ionics Co., Ltd. according to the BET one-point method (He / N ₂ mixed gas). In this example, the measurement was performed after the amount of the powder to be measured was 0.3 g and preliminary deaeration was performed at 105 ° C. for 10 minutes under atmospheric pressure.

  In this pot, 0.3% by mass of polyvinyl alcohol, 0.2% by mass of ammonium polycarboxylate, 0.5% by mass of polyethylene glycol, and 50% by mass of water were added to 100% by mass of the raw material powder. Was added, and the mixture was mixed with a ball mill to prepare a slurry. Next, this slurry was supplied to a spray-drying apparatus, and spray-dried under the conditions of an atomizer rotation speed of 14,000 rpm, an inlet temperature of 200 ° C, and an outlet temperature of 80 ° C to prepare granules.

This granule is filled while tapping into a cylindrical urethane rubber mold having an inner diameter of 220 mm (wall thickness: 10 mm) and a length of 630 mm having a cylindrical core (mandrel) having an outer diameter of 157 mm, and after sealing the rubber mold, CIP (Cold Isostatic Pressing) molding was performed under a pressure of 800 kgf / cm ² (about 78.5 MPa) to produce a substantially cylindrical molded body 12. The molded body 12 was heated at 600 ° C. for 10 hours to remove organic components. The heating rate was 50 ° C./h.

  Further, the molded body 12 from which the organic component was removed was fired to produce a fired body. The firing is performed in an oxygen atmosphere so that the outer peripheral surface 121 of the molded body 12 is supported by the receiving surfaces 81a and 81b along the length direction of the molded body 12 and is inclined with respect to the horizontal plane 7 in an oxygen atmosphere. The test was performed by disposing a V-shaped setter 8 (θ2 = 60 °). Further, a flat bottom plate 6 made of alumina was provided at an angle of 90 ° with respect to the V-shaped setter 8, and the bottom surface 123 of the molded body 12 was placed on the top surface 61 of the bottom plate 6. In addition, high-purity alumina powder was previously adhered to portions of the receiving surface 81 and the upper surface 61 that come into contact with the molded body 12. The inclination angle θ1 of the molded body 12 with respect to the horizontal plane 7 was 75 °. Further, the heating rate from normal temperature is set to 300 ° C./h, and the sintering temperature is heated to 1550 ° C. and held for 12 hours, and the cooling rate is 50 ° C./h from 1550 ° C. to 800 ° C. The firing conditions were set to ° C / h.

[Example 2]
And 25.9 wt% ZnO powder having a BET specific surface area of ^4m 2 / g, and _In 2 _{O 3} powder 44.2 wt% of the BET specific surface area of ^7m 2 / g, a BET specific surface area of ^10m ₂ / g Ga 2 O ₃ blended powder 29.9 wt%, and mixed in a ball mill with zirconia balls in a pot, to prepare a raw material powder.

  In this pot, with respect to 100% by mass of the raw material powder, 0.3% by mass of polyvinyl alcohol, 0.4% by mass of ammonium polycarboxylate, 1.0% by mass of polyethylene glycol, and 50% by mass of water Were added and mixed by a ball mill to prepare a slurry.

  Next, in the same manner as in Example 1, the preparation of the granules, the production of the molded body 12, and the removal of the organic components from the molded body 12 were performed.

  Further, the molded body 12 from which the organic component was removed was fired to produce a fired body. The firing is performed in an oxygen atmosphere so that the outer peripheral surface 121 of the molded body 12 is supported by the receiving surfaces 81a and 81b along the length direction of the molded body 12 and is inclined with respect to the horizontal plane 7 in an oxygen atmosphere. The test was performed by disposing a V-shaped setter 8 (θ2 = 45 °). Further, a flat bottom plate 6 made of alumina was provided at an angle of 90 ° with respect to the V-shaped setter 8, and the bottom surface 123 of the molded body 12 was placed on the top surface 61 of the bottom plate 6. In addition, high-purity alumina powder was previously adhered to portions of the receiving surface 81 and the upper surface 61 that come into contact with the molded body 12. The inclination angle θ1 of the molded body 12 with respect to the horizontal plane 7 was 75 °. The heating rate from normal temperature is 300 ° C./h, the heating temperature is 1400 ° C. and the temperature is maintained for 10 hours, and the cooling rate is 50 ° C./h from 1400 ° C. to 800 ° C. and 30 ° C. from 800 ° C. to normal temperature. The firing conditions were set to ° C / h.

[Example 3]
95 mass% of ZnO powder having a BET specific surface area of 4 m ² / g and 5 mass% of Al ₂ O ₃ powder having a BET specific surface area of 5 m ² / g are mixed with a zirconia ball in a pot and ball milled to obtain a raw material powder. Was prepared.

  In this pot, with respect to 100% by mass of the raw material powder, 0.3% by mass of polyvinyl alcohol, 0.4% by mass of ammonium polycarboxylate, 1.0% by mass of polyethylene glycol, and 50% by mass of water Were added and mixed by a ball mill to prepare a slurry.

  Next, in the same manner as in Example 1, the preparation of the granules, the production of the molded body 12, and the removal of the organic components from the molded body 12 were performed.

  Further, the molded body 12 from which the organic component was removed was fired to produce a fired body. The firing is performed in an oxygen atmosphere so that the outer peripheral surface 121 of the molded body 12 is supported by the receiving surfaces 81a and 81b along the length direction of the molded body 12 and is inclined with respect to the horizontal plane 7 in an oxygen atmosphere. The test was performed by disposing a V-shaped setter 8 (θ2 = 70 °). Further, a flat bottom plate 6 made of alumina was provided at an angle of 90 ° with respect to the V-shaped setter 8, and the bottom surface 123 of the molded body 12 was placed on the top surface 61 of the bottom plate 6. In addition, high-purity alumina powder was previously adhered to portions of the receiving surface 81 and the upper surface 61 that come into contact with the molded body 12. The inclination angle θ1 of the molded body 12 with respect to the horizontal plane 7 was 75 °. The heating rate from normal temperature is 300 ° C./h, the heating temperature is 1400 ° C. and the temperature is maintained for 10 hours, and the cooling rate is 50 ° C./h from 1400 ° C. to 800 ° C. and 30 ° C. from 800 ° C. to normal temperature. The firing conditions were set to ° C / h.

[Example 4]
10.7% by mass of ZnO powder having a BET specific surface area of 4 m ² / g and 89.3% by mass of In ₂ O ₃ powder having a BET specific surface area of 7 m ² / g were mixed with a ball mill in a pot with zirconia balls. Thus, a raw material powder was prepared.

  In this pot, with respect to 100% by mass of the raw material powder, 0.3% by mass of polyvinyl alcohol, 0.4% by mass of ammonium polycarboxylate, 1.0% by mass of polyethylene glycol, and 50% by mass of water Were added and mixed by a ball mill to prepare a slurry.

  Next, in the same manner as in Example 1, the preparation of the granules, the production of the molded body 12, and the removal of the organic components from the molded body 12 were performed.

  Further, the molded body 12 from which the organic component was removed was fired to produce a fired body. The firing is performed in an oxygen atmosphere so that the outer peripheral surface 121 of the molded body 12 is supported by the receiving surfaces 81a and 81b along the length direction of the molded body 12 and is inclined with respect to the horizontal plane 7 in an oxygen atmosphere. The test was performed by disposing a V-shaped setter 8 (θ2 = 80 °). Further, a flat bottom plate 6 made of alumina was provided at an angle of 90 ° with respect to the V-shaped setter 8, and the bottom surface 123 of the molded body 12 was placed on the top surface 61 of the bottom plate 6. In addition, high-purity alumina powder was previously adhered to portions of the receiving surface 81 and the upper surface 61 that come into contact with the molded body 12. The inclination angle θ1 of the molded body 12 with respect to the horizontal plane 7 was 75 °. The heating rate from normal temperature is 300 ° C./h, the heating temperature is 1400 ° C. and the temperature is maintained for 10 hours, and the cooling rate is 50 ° C./h from 1400 ° C. to 800 ° C. and 30 ° C. from 800 ° C. to normal temperature. The firing conditions were set to ° C / h.

[Example 5]
The molded body 12 was fired in the same manner as in Example 1 except that the arrangement of the V-shaped setter 8 was changed so that θ1 = 60 °.

[Example 6]
The molded body 12 was fired in the same manner as in Example 2 except that the arrangement of the V-shaped setter 8 was changed so that θ1 = 60 °.

[Example 7]
The molded body 12 was fired in the same manner as in Example 3 except that the arrangement of the V-shaped setter 8 was changed so that θ1 = 60 °.

Example 8
The molded body 12 was fired in the same manner as in Example 4 except that the arrangement of the V-shaped setter 8 was changed so that θ1 = 60 °.

[Example 9]
The molded body 12 was fired in the same manner as in Example 1 except that the arrangement of the V-shaped setter 8 was changed so that θ1 = 85 °.

[Example 10]
The molded body 12 was fired in the same manner as in Example 2, except that the arrangement of the V-shaped setter 8 was changed so that θ1 = 85 °.

[Example 11]
The molded body 12 was fired in the same manner as in Example 3 except that the arrangement of the V-shaped setter 8 was changed so that θ1 = 85 °.

[Example 12]
The molded body 12 was fired in the same manner as in Example 4, except that the arrangement of the V-shaped setter 8 was changed so that θ1 = 85 °.

Example 13
The molded body 12 was fired in the same manner as in Example 1 except that the flat bottom plate 6 was not provided.

[Example 14]
The molded body 12 was fired in the same manner as in Example 2 except that the flat bottom plate 6 was not provided.

[Example 15]
The molded body 12 was fired in the same manner as in Example 3 except that the flat bottom plate 6 was not provided.

[Example 16]
The molded body 12 was fired in the same manner as in Example 4 except that the flat bottom plate 6 was not provided.

[Example 17]
The molded body 12 was fired in the same manner as in Example 1 except that the arrangement of the V-shaped setter 8 was changed so that θ1 = 40 °.

[Example 18]
The molded body 12 was fired in the same manner as in Example 2, except that the arrangement of the V-shaped setter 8 was changed so that θ1 = 40 °.

[Example 19]
The molded body 12 was fired in the same manner as in Example 3 except that the arrangement of the V-shaped setter 8 was changed so that θ1 = 40 °.

[Example 20]
The molded body 12 was fired in the same manner as in Example 4, except that the arrangement of the V-shaped setter 8 was changed so that θ1 = 40 °.

[Example 21]
Production of the molded body 12 and removal of the organic component from the molded body 12 were performed in the same manner as in Example 1. Further, the molded body 12 from which the organic component was removed was fired to produce a fired body. The firing is performed in an oxygen atmosphere such that the outer peripheral surface 121 of the molded body 12 is supported on the receiving surface 51 along the length direction of the molded body 12 and the inclination angle θ1 of the molded body 12 with respect to the horizontal plane 7 is 75 °. The test was performed by disposing a setter 5 made of alumina. Further, a flat bottom plate 6 made of alumina was provided at an angle of 90 ° with respect to the setter 5, and the bottom surface 123 of the molded body 12 was placed on the top surface 61 of the bottom plate 6. In addition, high-purity alumina powder was previously adhered to portions of the receiving surface 51 and the upper surface 61 that are in contact with the molded body 12. The firing conditions were the same as in Example 1.

[Example 22]
Production of the molded body 12 and removal of the organic components from the molded body 12 were performed in the same manner as in Example 2. Further, the molded body 12 from which the organic component was removed was fired to produce a fired body. The firing is performed in an oxygen atmosphere such that the outer peripheral surface 121 of the molded body 12 is supported on the receiving surface 51 along the length direction of the molded body 12 and the inclination angle θ1 of the molded body 12 with respect to the horizontal plane 7 is 75 °. The test was performed by disposing a setter 5 made of alumina. Further, a flat bottom plate 6 made of alumina was provided at an angle of 90 ° with respect to the setter 5, and the bottom surface 123 of the molded body 12 was placed on the top surface 61 of the bottom plate 6. In addition, high-purity alumina powder was previously adhered to portions of the receiving surface 51 and the upper surface 61 that are in contact with the molded body 12. The firing conditions were the same as in Example 2.

[Example 23]
Production of the molded body 12 and removal of organic components from the molded body 12 were performed in the same manner as in Example 3. Further, the molded body 12 from which the organic component was removed was fired to produce a fired body. The firing is performed in an oxygen atmosphere such that the outer peripheral surface 121 of the molded body 12 is supported on the receiving surface 51 along the length direction of the molded body 12 and the inclination angle θ1 of the molded body 12 with respect to the horizontal plane 7 is 75 °. The test was performed by disposing a setter 5 made of alumina. Further, a flat bottom plate 6 made of alumina was provided at an angle of 90 ° with respect to the setter 5, and the bottom surface 123 of the molded body 12 was placed on the top surface 61 of the bottom plate 6. In addition, high-purity alumina powder was previously adhered to portions of the receiving surface 51 and the upper surface 61 that are in contact with the molded body 12. The firing conditions were the same as in Example 3.

[Example 24]
Production of the molded body 12 and removal of the organic component from the molded body 12 were performed in the same manner as in Example 4. Further, the molded body 12 from which the organic component was removed was fired to produce a fired body. The firing is performed in an oxygen atmosphere such that the outer peripheral surface 121 of the molded body 12 is supported on the receiving surface 51 along the length direction of the molded body 12 and the inclination angle θ1 of the molded body 12 with respect to the horizontal plane 7 is 75 °. The test was performed by disposing a setter 5 made of alumina. Further, a flat bottom plate 6 made of alumina was provided at an angle of 90 ° with respect to the setter 5, and the bottom surface 123 of the molded body 12 was placed on the top surface 61 of the bottom plate 6. In addition, high-purity alumina powder was previously adhered to portions of the receiving surface 51 and the upper surface 61 that are in contact with the molded body 12. The firing conditions were the same as in Example 4.

[Comparative Example 1]
A fired body was produced in the same manner as in Example 1 except that the formed body 12 was erected and fired so that θ1 = 90 ° without using the V-shaped setter 8.

[Comparative Example 2]
A fired body was produced in the same manner as in Example 2 except that the molded body 12 was erected and fired so that θ1 = 90 ° without using the V-shaped setter 8.

[Comparative Example 3]
A fired body was produced in the same manner as in Example 3, except that the formed body 12 was erected and fired so that θ1 = 90 ° without using the V-shaped setter 8.

[Comparative Example 4]
A fired body was produced in the same manner as in Example 4 except that the molded body 12 was erected and fired so that θ1 = 90 ° without using the V-shaped setter 8.

[Comparative Example 5]
A fired body was produced in the same manner as in Example 1, except that the arrangement of the V-shaped setter 8 was changed so that θ1 = 0 °.

[Comparative Example 6]
A fired body was produced in the same manner as in Example 2, except that the arrangement of the V-shaped setter 8 was changed so that θ1 = 0 °.

[Comparative Example 7]
A fired body was produced in the same manner as in Example 3, except that the arrangement of the V-shaped setter 8 was changed so that θ1 = 0 °.

[Comparative Example 8]
A fired body was produced in the same manner as in Example 4, except that the arrangement of the V-shaped setter 8 was changed so that θ1 = 0 °.

  In each of the examples and comparative examples, distortion was evaluated for a total of 10 fired bodies produced similarly. Specifically, a straight edge is applied to the outer peripheral surface of the fired body along the length direction of the fired body, and the largest value among the measured values of the gap between the outer peripheral surface of the fired body and the straight edge is defined as the largest value. The strain was set in the length direction of the fired body. In addition, the inner diameters of both end surfaces of the fired body were measured at eight positions at equal intervals in the circumferential direction using calipers, and the difference between the maximum value and the minimum value of the inner diameter measured at each end surface was determined. . Of the differences between the maximum value and the minimum value of the inner diameter obtained at both end surfaces of the fired body, the larger value was defined as the inner diameter strain, and was used as an index of the radial distortion of the fired body.

  In addition, a total of 10 fired bodies produced in each of the examples and comparative examples were finish-processed to produce a cylindrical target material 2 having an outer diameter of 153 mm, an inner diameter of 135 mm, and a length of 500 mm. Table 1 shows the average value of the relative densities of the obtained fired bodies, and the number of the cylindrical target materials 2 that could be manufactured from the obtained fired bodies (the number of workable pieces), together with the evaluation of distortion, in Table 1. The evaluation of distortion shown in Table 1 is based on the maximum value as a representative value among the values measured for each of the ten fired bodies manufactured.

  Further effects and modifications can be easily derived by those skilled in the art. For this reason, the broader aspects of the present invention are not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and equivalents thereof.

1 Cylindrical sputtering target (cylindrical target)
2 cylindrical target material 3 backing tube 4 bonding material 5, 10, 11 setter 6 bottom plate 7 horizontal plane 8 V-shaped setter 12 molded body 51, 81, 101, 111 receiving surface

Claims (9)

A molding step for producing a ceramic molded body molded into a cylindrical shape,
A firing step of firing the molded body in a posture in which an outer peripheral surface of the molded body is supported on a receiving surface of the setter along a length direction and is inclined with respect to a horizontal plane.   The method for producing a cylindrical target material according to claim 1, wherein an inclination angle of the molded body with respect to the horizontal plane is 30 ° or more and 85 ° or less.   The method for producing a cylindrical target material according to claim 1, wherein the setter is a flat plate setter.   3. The method for manufacturing a cylindrical target material according to claim 1, wherein the setter is a V-shaped setter. In the firing step,
The method for producing a cylindrical target material according to any one of claims 1 to 4, wherein a bottom plate on which an end surface of the molded body is placed is disposed and the molded body is fired. In the firing step,
The method for producing a cylindrical target material according to claim 5, wherein a co-base is disposed on the bottom plate and fired. The material of the V-shaped setter is any one of alumina, magnesia and zirconia,
The method for manufacturing a cylindrical target material according to claim 4, wherein the receiving surfaces of the V-shaped setter face each other at an angle of 25 ° or more and 80 ° or less. The molded body is an oxide containing at least one of In, Zn, Al, Ga, Zr, Ti, Sn, Mg, and Si,
Any one in comprising the step of producing by Lien cylindrical target materials to the manufacturing method of the cylindrical target material, wherein the cylindrical sputtering target producing process of claims 1-7. The method for manufacturing a cylindrical sputtering target according to claim 8, wherein the length of the cylindrical target material is 500 mm or more.

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