WO2014115379A1 - 円筒形Ｃｕ－Ｇａ合金スパッタリングターゲット及びその製造方法 - Google Patents

円筒形Ｃｕ－Ｇａ合金スパッタリングターゲット及びその製造方法 Download PDF

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WO2014115379A1
WO2014115379A1 PCT/JP2013/077832 JP2013077832W WO2014115379A1 WO 2014115379 A1 WO2014115379 A1 WO 2014115379A1 JP 2013077832 W JP2013077832 W JP 2013077832W WO 2014115379 A1 WO2014115379 A1 WO 2014115379A1
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Prior art keywords
alloy
capsule
density
cylindrical
sputtering target
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PCT/JP2013/077832
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English (en)
French (fr)
Japanese (ja)
Inventor
辰也 高橋
山岸　浩一
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住友金属鉱山株式会社
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Priority to CN201380071399.6A priority Critical patent/CN105008578B/zh
Priority to KR1020157020475A priority patent/KR20150105364A/ko
Publication of WO2014115379A1 publication Critical patent/WO2014115379A1/ja

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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/04—Making non-ferrous alloys by powder metallurgy
    • C22C1/0425—Copper-based alloys
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/12—Both compacting and sintering
    • B22F3/14—Both compacting and sintering simultaneously
    • B22F3/15—Hot isostatic pressing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F5/00—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
    • B22F5/10—Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product of articles with cavities or holes, not otherwise provided for in the preceding subgroups
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C9/00—Alloys based on copper
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
    • C23C14/34—Sputtering
    • C23C14/3407—Cathode assembly for sputtering apparatus, e.g. Target
    • C23C14/3414—Metallurgical or chemical aspects of target preparation, e.g. casting, powder metallurgy

Definitions

  • the present invention relates to a cylindrical Cu—Ga alloy sputtering target used for forming a light absorption layer of a CIGS (Cu—In—Ga—Se quaternary alloy) solar cell and a method of manufacturing the same.
  • CIGS Cu—In—Ga—Se quaternary alloy
  • the CIGS solar cell has, as a basic structure, a Mo electrode layer to be a back electrode formed on a soda lime glass substrate and a Cu—In—Ga— to be a light absorption layer formed on the Mo electrode layer.
  • a transparent electrode is a transparent electrode.
  • a vapor deposition method is known as a method for forming a light absorption layer made of a Cu—In—Ga—Se quaternary alloy film, but a method of forming by a sputtering method in order to obtain a uniform film over a wider area. Has been proposed.
  • an In film is formed by sputtering using an In target, and a Cu—Ga alloy film is formed on the In film by sputtering using a Cu—Ga alloy sputtering target.
  • This is a method of forming a Cu—In—Ga—Se quaternary alloy film by heat-treating the obtained laminated film composed of an In film and a Cu—Ga alloy film in a Se atmosphere.
  • the flat sputtering target has a drawback that the use efficiency is about 30%.
  • a Ga metal is a scarce resource, so that a target with excellent use efficiency is required.
  • a cylindrical (rotary) sputtering target has attracted attention.
  • the cylindrical sputtering target has a magnet and cooling equipment arranged inside the target and performs sputtering while rotating. Since the entire surface becomes an erosion area, the usage efficiency is as high as 60% or more. .
  • attention has been paid to the fact that high power can be applied per unit area as compared with the flat plate type, so that high-speed film formation is possible.
  • Patent Document 2 proposes a method of manufacturing a cylindrical sputtering target by thermal spraying.
  • the said manufacturing method is a manufacturing method which sprays a target raw material directly on a base material (it is also called a backing tube), and can manufacture a cylindrical sputtering target comparatively easily.
  • the production method by thermal spraying has a drawback that abnormal discharge is liable to occur during sputtering because many gaps are formed in the sputtering target.
  • the thermal spraying method in the process of depositing Cu—Ga alloy molten particles on the base material, Cu—Ga alloy molten particles that are not deposited on the base material are generated, and the yield is low compared to other manufacturing methods. There is.
  • Patent Document 3 a stainless steel columnar or cylindrical substrate is inserted into a mold (capsule), a target raw material is filled between the mold and the columnar substrate, and a hot isostatic press (A manufacturing method has been proposed in which a target bonded to a base material is manufactured by HIP) processing, and then a cylindrical target is manufactured by subjecting a cylindrical base material to inner peripheral processing.
  • HIP hot isostatic press
  • the sintering temperature depends on the composition, but it is necessary to process at a high temperature of about 500 to 1000 ° C. The higher the temperature, the greater the thermal stress that accompanies the difference in thermal expansion between the substrate and the Cu—Ga alloy.
  • Patent Document 3 does not describe the size of the columnar substrate or the cylindrical substrate, but the larger the substrate, the greater the thermal stress associated with the difference in thermal expansion. In particular, a brittle Cu—Ga alloy is not suitable because it is cracked even by a slight thermal stress.
  • the target and the base material are in a joined state, but there is usually no standard for the shape of the cylindrical base material, and there are various sizes and shapes depending on the sputtering apparatus. It is diverse. In the manufacturing method described in Patent Document 3, since the target and the base material are bonded, it is difficult to manufacture depending on the size and shape of the base material, which is not general-purpose.
  • the cylindrical sputtering target has been lengthened, and a target having a large size of 3000 mm or more is also desired.
  • the method of Patent Document 3 cannot divide the target, so that it is integrated. It will be limited.
  • a target of 3000 mm or more is to be manufactured, it becomes difficult to fill the target material at the time of HIP processing, so the density of the sintered body is reduced due to insufficient filling and density variation occurs. To do.
  • Such a sputtering target including insufficient sintering density and variation in density has a drawback that abnormal discharge is likely to occur during sputtering.
  • Patent Document 4 a cylindrical base material is formed by spraying an undercoat by thermal spraying for the purpose of alleviating thermal stress associated with the adhesion to the target and the difference in thermal expansion applied to the target, and performing a HIP treatment.
  • a manufacturing method for producing a target having a shape is proposed.
  • the undercoat formed by thermal spraying contains voids due to gas entrainment during thermal spraying. Therefore, the formed undercoat has a low density and contains a large amount of gas components.
  • the HIP treatment is performed using the base material on which such an undercoat is formed, the density of the obtained sintered body is not increased due to the influence of the gas component contained in the undercoat, and in the sintered body, A lot of gas components are contained. Therefore, the sputtering target obtained by the manufacturing method of Patent Document 4 has a drawback that abnormal discharge is likely to occur during sputtering.
  • Patent Document 5 proposes a method of obtaining a flat-plate sputtering target by pressure sintering.
  • Patent Document 6 proposes a method of manufacturing by a melting / casting method using a Cu—Ga alloy flat plate sputtering target.
  • segregation occurs in the solidification process after casting in an alloy system, resulting in variations in Ga concentration. Therefore, even if a cylindrical sputtering target is obtained by finishing the ingot into a cylindrical shape by machining, the composition of the obtained film varies when the sputtering target is used. The problem arises that the is not constant.
  • the present invention provides a high-quality cylindrical Cu—Ga alloy sputtering target that has a small relative density variation, a high density, and a small Ga concentration variation without causing defects such as cracks. It is an object of the present invention to provide a method for producing a cylindrical Cu—Ga alloy sputtering target to be produced and a cylindrical Cu—Ga alloy sputtering target obtained by the production method.
  • the amount of Ga is 20 to 40% by mass of Ga by weight, the balance is made of Cu and inevitable impurities, and the relative density is 99% or more.
  • the relative density variation is within 1.0%, and the Ga concentration variation is within 1.0 mass%.
  • the manufacturing method of a cylindrical Cu—Ga alloy sputtering target according to the present invention uses a hot isostatic pressing method, the amount of Ga is 20 to 40% by mass, the balance is Cu and unavoidable.
  • a method for producing a cylindrical Cu-Ga alloy sputtering target composed of impurities and a cylindrical capsule having a thickness of 1.0 mm or more and less than 3.5 mm is filled with Cu-Ga alloy powder or a Cu-Ga alloy compact. Filling so that the density is 60% or more, and hot isostatic pressing to obtain a Cu—Ga alloy sintered body.
  • FIG. 1 is a perspective view of a capsule used in the HIP process of the method for manufacturing a Cu—Ga alloy sputtering target according to the present invention.
  • FIG. 2 is a cross-sectional view of the capsule.
  • FIG. 3 is a top view of the capsule.
  • a cylindrical Cu—Ga alloy sputtering target (hereinafter also simply referred to as a target) has an amount of Ga of 20 to 40% by mass and the balance of Cu and inevitable impurities.
  • the amount of Ga is less than 20% by mass, when the light absorption layer of the solar cell is formed using the produced target, the desired battery characteristics cannot be obtained, which is not preferable.
  • the relative density of the cylindrical Cu—Ga alloy sputtering target is 99% or more.
  • the relative density means a percentage of a value obtained by dividing the density measured by the Archimedes method by the true density of the substance.
  • the relative density of the target is lower than 99%, problems such as abnormal discharge at the time of sputtering occur due to the influence of gas components existing in the gap of the target. Therefore, the relative density of the cylindrical Cu—Ga alloy sputtering target is 99% or more.
  • the cylindrical Cu—Ga alloy sputtering target has a relative density variation of 1.0% or less.
  • the variation in the relative density is defined as a value obtained by subtracting the maximum value and the minimum value of the relative density in each part of the target.
  • a plurality of points are arbitrarily determined on one surface in the longitudinal direction of the target (for example, the bottom surface of a cylinder). Then, the density of the target at the same position as the positions of a plurality of arbitrarily determined points is measured at both end portions in the length direction of the target and an intermediate portion located at half of the total length. And the relative density of each part is calculated
  • Arbitrary plural points are determined so that the portions for measuring the density are dispersed.
  • a straight line is drawn on one surface in the longitudinal direction of the target, and a total of four points including two points on the straight line and two points on a line drawn perpendicularly to the line are defined as a plurality of arbitrary points.
  • the number of points on the straight line is not limited to two, and may be two or more.
  • the cylindrical Cu—Ga alloy sputtering target has a density variation within 1.0%. If the relative density varies, the sputter rate is different at each part, so that the sputtered film thickness varies depending on the part. In particular, in a solar cell target, the variation in film thickness causes variation in characteristics, and therefore, the variation in relative density needs to be within 1.0%.
  • the cylindrical Cu—Ga alloy sputtering target has a variation of Ga concentration within 1.0 mass% in the composition of each part.
  • the variation in density defines a value obtained by subtracting the maximum value and the minimum value of the density at each part.
  • Each part is determined in the same manner as the above-described variation in relative density.
  • the Ga concentration varies, a Ga-rich fragile compound is formed depending on the part, so that a problem occurs when the cylindrical sputtering target is machined.
  • the Ga concentration also varies in the formed film, which affects the solar cell characteristics, so the variation in Ga concentration is 1.0 mass. %.
  • the cylindrical Cu—Ga alloy sputtering target has a high density and a small variation in density, and therefore does not cause problems such as abnormal discharge during sputtering.
  • the variation in Ga concentration is small in the cylindrical Cu—Ga alloy sputtering target, the variation in Ga concentration can be reduced even in a film formed by sputtering, and the occurrence of defects in the film can be suppressed. Therefore, for example, when a light absorption layer of a solar cell is formed using the above-described target, a light absorption layer having a predetermined Ga concentration can be formed without variation in Ga concentration. Therefore, with the cylindrical Cu—Ga alloy sputtering target, sputtering can be stably performed, and a high-quality sputtered film can be formed.
  • a Cu—Ga alloy powder adjusted to a predetermined composition or a Cu—Ga alloy molded body obtained by molding a Cu—Ga alloy powder is used as a raw material, and the thickness is controlled.
  • a die for an isostatic pressing (HIP) method (hereinafter also simply referred to as a capsule) is used.
  • the HIP treatment is performed by filling the capsule with the raw material by controlling the filling density and the clearance with the capsule.
  • the manufacturing method of the cylindrical Cu—Ga alloy sputtering target includes a powder manufacturing process, a forming process, an HIP process, and a machining process.
  • Powder manufacturing process In the powder manufacturing process, Cu—Ga alloy powder is produced.
  • the method for producing the Cu—Ga alloy powder is not particularly limited, and for example, a pulverization method or an atomization method can be used.
  • Cu raw material and Ga raw material are melted in a melting furnace or the like and then cast.
  • the obtained Cu—Ga alloy ingot is pulverized by a stamp mill, a disk mill or the like, whereby a lump powder can be obtained.
  • the Cu raw material and the Ga raw material are dissolved and then atomized. Since the HIP process is performed in a subsequent process, a spherical gas atomized powder having a high tap density is preferable.
  • the particle size of the Cu—Ga alloy powder used in the hot isostatic pressing method is not particularly limited, but the more the Cu—Ga alloy powder is filled in the capsule, the lower the shrinkage rate when pressure is applied when performing HIP processing. Therefore, a higher tap density is preferable. Therefore, it is preferable that the Cu—Ga alloy powder has a wide particle size distribution with less fine powder of 1 ⁇ m or less and less coarse powder of 200 ⁇ m or more.
  • the forming method of the Cu—Ga alloy powder may be a cold isostatic pressing (CIP) method or a molding press.
  • CIP cold isostatic pressing
  • the molding by CIP has no friction with the metal and isotropically loaded with pressure, so that the density becomes uniform.
  • the mold press is expensive because the mold is expensive, but CIP is economical because it uses an inexpensive rubber mold, and therefore molding by CIP is preferable.
  • the rubber mold to be used is a cylindrical outer frame, an inner cylinder that becomes a hollow portion of the target at the center of the outer frame, an upper lid that closes the upper and lower openings of the outer frame, and a lower And a lid.
  • the deformation resistance of the rubber mold is preferably small. Therefore, the upper and lower lids and the outer frame are preferably soft rubber.
  • the inner cylinder is preferably a hard rubber because it is necessary to maintain the inner diameter, and may be a metal inner cylinder instead of rubber.
  • a rubber mold is filled with Cu—Ga alloy powder and pressed in the same direction to obtain a molded body.
  • the conditions for the CIP treatment are not particularly limited, but in order to obtain a sufficient consolidation effect, it is preferably 100 MPa or more, and more preferably 200 to 350 MPa.
  • the Cu-Ga alloy molded body after the CIP treatment is deformed by the pressure applied during the CIP process, the deformed Cu-Ga alloy molded body is subjected to machining or the like, and a cylindrical Cu-Ga alloy without deformation is obtained. You may finish in a molded object.
  • the Cu—Ga alloy compact is processed to have an outer diameter of 50 to 500 mm, for example.
  • HIP process the Cu—Ga alloy powder obtained in the powder production process or the Cu—Ga alloy compact obtained in the compact process is sintered by a hot isostatic pressing (HIP) method.
  • HIP hot isostatic pressing
  • a manufacturing method using a hot press As a method for heating and pressurizing, for example, a manufacturing method using a hot press is conceivable.
  • a manufacturing method using a hot press since the pressing direction is uniaxial, variation in relative density of the obtained sintered body becomes large. .
  • a graphite mold is required to obtain a sintered body by hot pressing, but it is not preferable because a graphite-type component becomes complicated to obtain a cylindrical sintered body.
  • the HIP method since it is a rubber mold, it can be easily produced even in a cylindrical shape, and since pressure can be applied in the same direction, the density of the obtained sintered body varies. In general, a high-density sintered body of approximately 95% or more can be obtained, although the density depends on the material.
  • a mold such as a mold with Cu-Ga alloy powder or Cu-Ga alloy compact.
  • the material of the capsule is not particularly limited, and for example, iron or stainless steel is used.
  • Using a high-strength material such as Mo or W takes time and labor to produce capsules, and also resists stress applied to the workpiece when pressure is applied by HIP treatment, resulting in a decrease in the density of the resulting sintered body. This is not preferable.
  • a capsule 1 having a bottom as shown in FIG. 1 is used as a capsule used for obtaining a cylindrical sintered body.
  • the method for producing the capsule 1 is not particularly limited.
  • the cylindrical outer frame 2, the cylindrical inner cylinder 3 serving as a hollow portion of the target disposed in the center of the outer frame 2, and the lower side of the outer frame 2 It is obtained by welding with the lower lid 4 that closes the opening.
  • the thickness of the capsule 1 needs to be 1.0 mm or more and less than 3.5 mm. When the thickness is less than 1.0 mm, it becomes difficult to weld each capsule component. Therefore, in some cases, the welding is poor, the capsule is broken at the poorly welded portion during the HIP process, and the HIP is put in the capsule 1 which is decompressed. Gas that is a pressure medium for the treatment is mixed. When gas is mixed in the capsule 1, the internal pressure increases, the differential pressure from the external pressure is reduced, and the pressure applied to the object to be processed is insufficient, so that the density of the sintered body is insufficient.
  • the thickness of the capsule 1 needs to be 1.0 mm or more and less than 3.5 mm.
  • Cu—Ga alloy powder or a Cu—Ga alloy molded body is filled between the outer frame 2 and the middle cylinder 4 of the capsule 1, and the opening of the outer frame 2 is sealed with the upper lid 5. Is degassed and HIP treatment is performed.
  • the filling density is 60% or more.
  • the filling density refers to a percentage of a value obtained by dividing the weight of the Cu—Ga alloy powder or Cu—Ga alloy molded body filled in the capsule 1 by the volume of the capsule 1 and dividing by the true density of the substance. .
  • the packing density is lower than 60%, the capsule 1 is greatly deformed when the HIP treatment is performed, and the stress applied to the object to be processed increases due to excessive deformation, but the Cu—Ga alloy is brittle, so the capsule 1 Cracks or cracks occur without being able to withstand the stress.
  • the deformation amount of the capsule 1 reaches the limit, the capsule 1 is torn and the pressure applied to the object to be processed is insufficient, resulting in insufficient density.
  • the filling density is 60% or more, the occurrence of defects such as cracks and insufficient density is eliminated, and the relative density of the Cu—Ga alloy after HIP treatment is preferably high. Since a high-density thing is obtained, it is preferable. Further, the higher the packing density, the lower the shrinkage rate during HIP, so that a sintered body closer to the product shape can be obtained. Therefore, the packing density is 60% or more.
  • the method of filling the capsule 1 with the Cu—Ga alloy powder is not particularly limited, and may be filled in small portions and tapped.
  • a vibrating plate is placed under the capsule 1 and filled while applying vibration.
  • the gap (clearance) between the capsule 1 and the object to be treated is preferably 1 mm or less.
  • the apparent clearance is 0 mm.
  • the clearance between the Cu—Ga alloy powder and the capsule 1 is filled with a Cu—Ga alloy powder having the same composition as the Cu—Ga alloy compact to adjust the clearance.
  • the foil of the same material as the capsule 1 is filled.
  • the clearance between the capsule 1 and the object to be processed is larger than 1.0 mm
  • the capsule 1 is deformed, but generally the deformation is most deformed at the central portion.
  • the clearance between the capsule 1 and the object to be processed is preferably 1.0 mm or less.
  • the upper lid 5 is sealed to the opening of the outer frame 2 by welding as shown in FIGS.
  • the method of welding the upper lid 5 is not particularly limited, and may be, for example, TIG welding (TIG (Tungsten Inert Gas) welding) or electron beam welding (EB (electron beam welding) welding).
  • TIG welding TIG (Tungsten Inert Gas) welding
  • EB electron beam welding
  • EB welding is preferable because the welding accuracy is good and the heat influence on the capsule 1 is small.
  • the inside of the capsule 1 is deaerated.
  • the pressure is reduced to 1 ⁇ 10 1 Pa or less through the deaeration pipe 6 shown in FIGS. 2 and 3, and then the deaeration pipe 6 is pressure-bonded and welded to be sealed.
  • Degassing is preferably performed by heating at 150 ° C. or higher.
  • HIP treatment is performed in the presence of a small amount of gas component adhering to the capsule 1 and the object to be processed, the gas component remains in the sintered body and causes voids and lowers the target density. Become. Therefore, it is preferable to heat at the time of deaeration before HIP, and a high-density and high-purity sintered body can be obtained by heating at 150 ° C. or higher.
  • the capsule 1 filled with the Cu—Ga alloy or Cu—Ga alloy molded body in this way is subjected to HIP treatment.
  • the conditions for the HIP treatment are not particularly limited, but it is preferable that the temperature is 500 to 900 ° C., the pressure is 50 to 200 MPa, and the treatment time is 2 hours or more.
  • the temperature is less than 500 ° C., the progress of the sintering is slow, and it becomes difficult to obtain a high-density sintered body.
  • a temperature higher than 900 ° C. is not preferable because a liquid phase due to Ga starts to appear and alloyed with the capsule 1 to cause a significant defect.
  • the pressure is preferably 50 MPa or more in order to obtain a high-density sintered body.
  • the maximum pressure of a general apparatus is 200 MPa, and if it exceeds that, a special HIP apparatus will be used, and the cost increases.
  • the Cu—Ga alloy powder or Cu—Ga is preferably used in the cylindrical capsule 1 having a thickness of 1.0 mm or more and less than 3.5 mm so that the clearance is preferably 1.0 mm or less.
  • the inside of the capsule 1 is deaerated, and for example, the temperature is set within the range of 500 to 900 ° C. and the pressure is set within the range of 50 to 200 MPa, and the HIP treatment is performed for 2 hours or more.
  • a high-density Cu—Ga alloy sintered body can be formed without generating cracks and the like.
  • the capsule 1 attached to the obtained Cu—Ga alloy sintered body is removed.
  • the capsule 1 is removed with a lathe.
  • the sintered body from which the capsule 1 is removed is finished.
  • the processing method varies depending on the composition, and in the case of a Cu—Ga alloy having a Ga content of less than 30% by mass, it can be finished by processing with a lathe as it is.
  • a lathe As it is.
  • a Cu—Ga alloy having a Ga content of 30% by mass or more since it is fragile, there is a risk of cracking in processing on a lathe, so that it can be finished with, for example, a cylindrical grinder using a grindstone.
  • the thickness is 1.0 mm or more in order to suppress the stress applied to the Cu—Ga alloy when manufacturing using the HIP method.
  • Capsules of less than 3.5 mm are filled with Cu—Ga alloy powder or Cu—Ga alloy molded body so that the filling density is 60% or more, and subjected to HIP treatment.
  • the Cu—Ga alloy powder is so prepared that the clearance between the capsule 1 and the Cu—Ga alloy powder or the Cu—Ga alloy molded body is 1.0 mm or less.
  • the Cu—Ga alloy molded body by filling the Cu—Ga alloy molded body, generation of cracks due to deformation of the capsule 1 can be more effectively prevented.
  • the target obtained by this cylindrical Cu—Ga alloy sputtering target manufacturing method is free from cracks and cracks, and has high density and small variations in relative density and Ga concentration. It is possible to prevent problems such as variation in composition. Thereby, stable solar cell characteristics can be obtained by using this target.
  • Example 1 the powder manufacturing process was first performed. In the powder production process, in order to produce a cylindrical Cu—Ga alloy sputtering target, 25% by mass of Ga as a starting material is mixed and melted and cast so that the balance is Cu, thereby forming a Cu—Ga alloy ingot. Obtained. Thereafter, the ingot was pulverized by a disk mill and classified to obtain a Cu—Ga alloy powder. The average particle diameter of the Cu—Ga alloy powder after classification was 90 ⁇ m and the tap density was 5.0 g / cm 3 .
  • the produced Cu—Ga alloy powder was molded by CIP, so that the Cu—Ga alloy powder was filled in a rubber mold and processed at a pressure of 250 MPa to obtain a Cu—Ga alloy molded body.
  • the HIP process was performed.
  • the upper and lower lids, outer frame, and hollow inner cylinder are machined from a 3.2 mm thick steel plate.
  • the bottom lid, outer frame, and inner cylinder were electron beam (EB) welded to obtain a capsule with a bottomed outer diameter ⁇ 180 mm, inner diameter ⁇ 130 mm, and length 300 mmL (see FIG. 1).
  • the filling density was 8.6 g / specific gravity of the Cu—Ga alloy. It was 65.2% with respect to cm 3 .
  • the capsule was sealed by deaeration from the deaeration pipe while heating, and crimping and welding the upper lid.
  • the capsule was subjected to HIP treatment, and as a condition thereof, a Cu—Ga alloy sintered body was obtained by performing treatment at a temperature of 650 ° C. and a pressure of 100 MPa for a treatment time of 3 hours.
  • the capsule adhering to the Cu—Ga alloy sintered body was removed by a lathe process, the outer diameter and inner diameter of the Cu—Ga alloy were machined by a lathe to finish to an arbitrary dimension. Thereafter, a penetrant inspection was performed to confirm cracks on the surface, but no cracks or cracks were found.
  • the relative density was calculated by dividing the obtained value by the true density of 8.6 g / cm 3 and dividing the divided value as a percentage. As a result, the average value of the relative density was 99.8%. The maximum value of the relative density was 100%, the minimum value was 99.6%, and the variation obtained by subtracting the minimum value from the maximum value was 0.4%.
  • Example 2 In Example 2, in the powder manufacturing process, Ga as a starting material was mixed and dissolved so that 25 mass% and the balance was Cu, and prepared by gas atomization, and classified to obtain a Cu-Ga alloy powder. .
  • the average particle diameter of the classified Cu—Ga alloy powder was 45 ⁇ m and the tap density was 6.2 g / cm 3 .
  • the Cu—Ga alloy powder was filled between the inner cylinder and the outer frame of the capsule produced in the same manner as in Example 1 while tapping, and the filling density was 8. It was 71.8% with respect to 6 g / cm 3 . Thereafter, the capsule was sealed by deaeration from the deaeration pipe while heating, and crimping and welding the upper lid (see FIG. 2).
  • Example 2 HIP treatment was performed in the same manner as in Example 1 to obtain a Cu—Ga alloy sintered body. And in order to confirm the presence or absence of the crack by the HIP process, and the generation
  • the capsule was removed from the Cu—Ga alloy sintered body in the same manner as in Example 1, and then processed to finish to an arbitrary size. Thereafter, a penetration inspection was conducted to confirm cracks on the surface, but no cracks were found.
  • Example 3 In Example 3, in the powder manufacturing process, 25% by mass of Ga as a starting material was mixed and dissolved and cast so that the balance was Cu, thereby obtaining a Cu—Ga alloy ingot. Thereafter, the ingot was pulverized by a disk mill and classified to obtain a Cu—Ga alloy powder. The average particle diameter of the Cu—Ga alloy powder after classification was 90 ⁇ m and the tap density was 5.0 g / cm 3 .
  • capsules were produced in the same manner as in Example 1 using a steel plate having a thickness of 1.0 mm.
  • the Cu—Ga alloy molded body was filled between the inner cylinder and the outer frame of the capsule, and further filled with the Cu—Ga alloy powder while tapping, and the filling density was 8.6 g / specific gravity of the Cu—Ga alloy. It was 65.2% with respect to cm 3 . Thereafter, the capsule was sealed by deaeration from the deaeration pipe while heating and crimping and welding the upper lid.
  • Example 2 HIP treatment was performed in the same manner as in Example 1 to obtain a Cu—Ga alloy sintered body. And in order to confirm the presence or absence of the crack by the HIP process, and the generation
  • the capsule was removed from the Cu—Ga alloy sintered body in the same manner as in Example 1, and then processed to finish to an arbitrary size. Thereafter, a penetration inspection was conducted to confirm cracks on the surface, but no cracks were found.
  • Example 4 in the powder manufacturing process, 25% by mass of Ga as a starting material was mixed and dissolved and cast so that the balance was Cu, thereby obtaining a Cu—Ga alloy ingot. Thereafter, the ingot was pulverized by a disk mill and classified to obtain a Cu—Ga alloy powder.
  • the average particle diameter of the Cu—Ga alloy powder after classification was 90 ⁇ m and the tap density was 5.0 g / cm 3 .
  • capsules were produced in the same manner as in Example 1 using a steel plate having a thickness of 3.2 mm.
  • the filling density was 65.0% with respect to the specific gravity of 8.6 g / cm 3 of the Cu—Ga alloy.
  • the capsule was sealed by deaeration from the deaeration pipe while heating, and crimping and welding the upper lid.
  • Example 2 HIP treatment was performed in the same manner as in Example 1 to obtain a Cu—Ga alloy sintered body. And in order to confirm the presence or absence of the crack by the HIP process, and the generation
  • the capsule was removed from the Cu—Ga alloy sintered body in the same manner as in Example 1, and then processed to finish to an arbitrary size. Thereafter, a penetration inspection was conducted to confirm cracks on the surface, but no cracks were found.
  • Example 5 In Example 5, in the powder manufacturing process, 35% by mass of Ga as a starting material was mixed and dissolved and cast so that the balance was Cu, thereby obtaining a Cu—Ga alloy ingot. Thereafter, the ingot was pulverized by a disk mill and classified to obtain a Cu—Ga alloy powder. The average particle diameter of the classified Cu—Ga alloy powder was 72 ⁇ m and the tap density was 5.2 g / cm 3 .
  • capsules were produced in the same manner as in Example 1 using a steel plate having a thickness of 3.2 mm.
  • the filling density was 8.4 g / specific gravity of the Cu—Ga alloy. It was 68.6% with respect to cm 3 .
  • the capsule was sealed by deaeration from the deaeration pipe while heating and crimping and welding the upper lid.
  • a Cu—Ga alloy sintered body was obtained by performing a treatment at a temperature of 600 ° C. and a pressure of 90 MPa for a treatment time of 3 hours.
  • the capsule was removed from the sintered body of the Cu—Ga alloy in the same manner as in Example 1 and processed to finish to an arbitrary size. Thereafter, a penetration inspection was conducted to confirm cracks on the surface, but no cracks were found.
  • Comparative Example 1 In Comparative Example 1, a Cu—Ga alloy ingot was obtained by melting and casting in a powder production process by mixing and casting 42% by weight of Ga as a starting material and the balance of Cu. Thereafter, the ingot was pulverized by a disk mill and classified to obtain a Cu—Ga alloy powder. The average particle diameter of the Cu—Ga alloy powder after classification was 69 ⁇ m and the tap density was 5.3 g / cm 3 .
  • capsules were produced in the same manner as in Example 1 using a steel plate having a thickness of 3.2 mm.
  • the filling density was 8.4 g / specific gravity of the Cu—Ga alloy. It was 69.8% with respect to cm 3 .
  • the capsule was sealed by deaeration from the deaeration pipe while heating and crimping and welding the upper lid.
  • a Cu—Ga alloy sintered body was obtained by performing a treatment for 3 hours at a temperature of 400 ° C. and a pressure of 80 MPa.
  • the capsule adhering to the sintered body of the Cu—Ga alloy was removed by a lathe process, and then processed by a cylindrical grinder, but the process was stopped because the crack progressed and a crack occurred.
  • Comparative Example 2 In Comparative Example 2, a Cu—Ga alloy ingot was obtained by mixing and melting in a powder production process so that Ga as a starting material was 25% by mass and the balance was Cu. Thereafter, the ingot was pulverized by a disk mill and classified to obtain a Cu—Ga alloy powder. The average particle diameter of the Cu—Ga alloy powder after classification was 90 ⁇ m and the tap density was 5.0 g / cm 3 .
  • capsules were produced in the same manner as in Example 1 using a steel plate having a thickness of 3.2 mm.
  • the filling density was 58.1% with respect to the specific gravity of Cu—Ga alloy of 8.6 g / cm 3 . It was. Thereafter, the capsule was sealed by deaeration from the deaeration pipe while heating and crimping and welding the upper lid.
  • a Cu—Ga alloy sintered body was obtained by performing a treatment for 3 hours at a temperature of 650 ° C. and a pressure of 100 MPa.
  • the normal part was extracted and sampled at the same place as in Example 1 in order to confirm the density and the variation of the density, and each sample was processed into a 10 mm square.
  • the density was measured by the Archimedes method, the average value of the relative density was 96.2% with respect to the true density of 8.6 g / m 3 .
  • the variation in relative density was 1.2%.
  • the Ga concentration of each part was analyzed, the average value of the Ga concentration was 25.2% by mass, and the variation in the Ga concentration was 0.1% by mass.
  • Comparative Example 3 In Comparative Example 3, a Cu—Ga alloy ingot was obtained in the powder production process by mixing and casting so that Ga as a starting material was 25% by mass and the balance was Cu. Thereafter, the ingot was pulverized by a disk mill and classified to obtain a Cu—Ga alloy powder. The average particle diameter of the Cu—Ga alloy powder after classification was 90 ⁇ m and the tap density was 5.0 g / cm 3 .
  • capsules were produced in the same manner as in Example 1 using a steel plate having a thickness of 3.8 mm.
  • the filling density was 8.6 g / specific gravity of the Cu—Ga alloy. It was 65.2% with respect to cm 3 .
  • the capsule was sealed by deaeration from the deaeration pipe while heating and crimping and welding the upper lid.
  • a Cu—Ga alloy sintered body was obtained by performing a treatment for 3 hours at a temperature of 650 ° C. and a pressure of 100 MPa.
  • the capsule adhering to the sintered body of the Cu—Ga alloy was removed by a lathe and then machined by a lathe. However, since the crack progressed and a crack was generated, the process was stopped.
  • Comparative Example 4 a Cu—Ga alloy ingot was obtained by melting and casting in a powder production process such that Ga as a starting material was 25 mass% and the balance was Cu. Thereafter, the ingot was pulverized by a disk mill and classified to obtain a Cu—Ga alloy powder. The average particle diameter of the Cu—Ga alloy powder after classification was 90 ⁇ m and the tap density was 5.0 g / cm 3 .
  • capsules were prepared using a steel plate having a thickness of 0.5 mm.
  • the filling density was 8.6 g / specific gravity of the Cu—Ga alloy. It was 65.2% with respect to cm 3 .
  • the capsule was sealed by deaeration from the deaeration pipe while heating and crimping and welding the upper lid.
  • the capsule is subjected to HIP processing.
  • the treatment was performed at a temperature of 650 ° C. and a pressure of 100 MPa for a treatment time of 3 hours.
  • cracks were observed in the weld.
  • the radiographic inspection was not performed, and the capsule adhering to the sintered body of the Cu—Ga alloy was removed by a lathe process, and then processed by a cylindrical grinder to finish to an arbitrary dimension. Then, when a penetration inspection was conducted to confirm cracks on the surface, cracks were detected in several places.
  • Example 2 In the obtained sintered body of Cu—Ga alloy, a normal part was extracted and sampled at the same location as in Example 1 in order to confirm the relative density and the variation in the relative density, and each sample was processed into a 10 mm square.
  • the density was measured by the Archimedes method, the average value of the relative density was 83.1% with respect to the true density of 8.6 g / m 3 .
  • the variation in relative density was 6.1%.
  • the Ga concentration of each part was analyzed, the average value of the Ga concentration was 25.0% by mass, and the variation in the Ga concentration was 0.2% by mass.
  • Example 1 in order to produce a cylindrical Cu—Ga alloy sputtering target, Ga as a starting material is mixed and dissolved so that 25 mass% and the balance is Cu, and then cast into a round mold. A columnar Cu—Ga alloy ingot was obtained. Next, the inner surface and the outer surface were turned to a desired size by turning. Thereafter, a penetration inspection was conducted to confirm cracks on the surface, but no cracks were found.
  • the hot isostatic pressing method was used, the capsule thickness was 1.0 mm or more and less than 3.5 mm, and the filling of Cu-Ga alloy powder or Cu-Ga alloy molded body In Examples 1 to 5 in which the density is 60% or more and the Ga concentration is 20 to 40%, cracks and cracks do not occur in the manufacturing process, there is no variation in relative density, and there is no variation in the Ga concentration.
  • a cylindrical Cu—Ga alloy sputtering target was also obtained.
  • Comparative Examples 1 to 4 in which the capsule thickness is 1.0 mm or more and less than 3.5 mm, the packing density of the Cu—Ga alloy powder or the Cu—Ga alloy molded body is 60% or more, and the Ga concentration is not 20-40%. Then, cracks and cracks occurred, and variations in relative density increased.

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WO2016013514A1 (ja) * 2014-07-24 2016-01-28 三菱マテリアル株式会社 Ｃｕ－Ｇａ合金円筒型スパッタリングターゲット及びＣｕ－Ｇａ合金円筒型鋳塊
CN109972100A (zh) * 2019-05-13 2019-07-05 无锡飞而康新材料科技有限公司 一种管状铬靶材的制备方法
EP3639953A1 (en) * 2018-10-19 2020-04-22 United Technologies Corporation Powder metallurgy method using a four-wall cylindrical canister

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JP5887625B1 (ja) * 2015-03-27 2016-03-16 Ｊｘ金属株式会社 円筒型スパッタリングターゲット、円筒型焼結体、円筒型成形体及びそれらの製造方法
JP2016191092A (ja) * 2015-03-30 2016-11-10 三菱マテリアル株式会社 円筒型スパッタリングターゲットの製造方法
JP6888294B2 (ja) * 2016-02-03 2021-06-16 三菱マテリアル株式会社 Ｃｕ−Ｇａ合金スパッタリングターゲットの製造方法、及び、Ｃｕ−Ｇａ合金スパッタリングターゲット
JP6557696B2 (ja) * 2017-03-31 2019-08-07 Ｊｘ金属株式会社 円筒型スパッタリングターゲット及びその製造方法
WO2019194275A1 (ja) * 2018-04-04 2019-10-10 三菱マテリアル株式会社 Ｃｕ－Ｇａ合金スパッタリングターゲット
CN111058004A (zh) * 2020-01-02 2020-04-24 宁波江丰电子材料股份有限公司 一种铬硅合金溅射靶材及其制备方法
CN114030217B (zh) * 2021-11-29 2023-06-20 航天特种材料及工艺技术研究所 一种筒形纳米隔热材料及其制备方法

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