JP5488377B2 - Method for producing Cu-Ga alloy sputtering target and Cu-Ga alloy sputtering target - Google Patents

Description

  The present invention relates to a method for producing a 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 Cu—Ga alloy sputtering target. .

  In recent years, photovoltaic power generation has attracted attention as one of clean energy. Although crystalline Si solar cells are mainly used, CIGS (Cu—In—Ga—Se quaternary alloy) solar cells with high conversion efficiency are attracting attention because of supply and cost problems. Yes.

  The CIGS solar cell has, as a basic structure, a Mo electrode layer serving as a back electrode formed on a soda lime glass substrate and a Cu—In—Ga—Se serving as a light absorption layer formed on the Mo electrode layer. A quaternary alloy film, a buffer layer made of ZnS, CdS, etc. formed on the light absorption layer made of this Cu-In-Ga-Se quaternary alloy film, and formed on this buffer layer A transparent electrode.

  As a method for forming a light absorption layer made of a Cu—In—Ga—Se quaternary alloy film, a vapor deposition method is known. In order to obtain a uniform film with a larger area, a metal produced by sputtering is used. A method for selenizing a precursor film has been proposed (see, for example, Patent Document 1).

  Specifically, a stacked film composed of an In film and a Cu—Ga alloy film obtained by sputtering using an In target and a Cu—Ga alloy sputtering target is heat-treated in a Se atmosphere to form a Cu—In—Ga. This is a method of forming a Se quaternary alloy film. Since the quality of the Cu—In—Ga—Se quaternary alloy film formed by this sputtering method largely depends on the quality of the Cu—Ga alloy sputtering target, a high quality Cu—Ga alloy sputtering target is desired. Yes. In addition, an inexpensive Cu—Ga alloy sputtering target is desired for further mass production.

  As a method for producing a Cu—Ga alloy sputtering target, a melting method and a powder sintering method are known. The melting method has a problem that a Cu-Ga alloy having a composition for a melt cast CIGS solar cell is brittle and easily cracked. On the other hand, the powder sintering method is regarded as a promising method for producing a sputtering target because a uniform composition can be obtained.

  As the powder sintering method, for example, a method is described in which a high Ga content Cu—Ga alloy powder and pure Cu or low Ga content Cu—Ga alloy powder are blended to produce a sputtering target by hot pressing. (For example, refer to Patent Document 2).

Japanese Patent No. 3249408 JP 2008-138232 A

  Since the raw material Ga has a melting point of 29.78 ° C. and an extremely low melting point, a sintered body cannot be obtained directly from Cu powder and Ga. For this reason, in the powder sintering method, Cu—Ga alloy powder is used as a raw material.

  However, when a Cu—Ga alloy sputtering target is produced using Cu—Ga alloy powder, if the homogenization reaction of the Cu—Ga alloy powder is not sufficiently advanced, a Ga liquid phase is locally generated. End up. When pressure-sintering the Cu—Ga alloy powder in which such a liquid phase is generated, leakage of the liquid phase occurs, defects such as cracks occur, and a usable high-quality Cu—Ga alloy sputtering target is obtained. I can't.

  Accordingly, there is a need for a method that can produce a high-quality Cu—Ga alloy sputtering target without causing defects such as cracks in the powder sintering method.

  Therefore, the present invention has been proposed in view of such conventional situations, and a high-quality Cu—Ga alloy powder is produced without causing defects such as cracks by producing a high-quality Cu—Ga alloy powder. It aims at providing the manufacturing method of a Cu-Ga alloy sputtering target which can manufacture a sputtering target, and a Cu-Ga alloy sputtering target.

  The manufacturing method of the Cu-Ga alloy sputtering target which concerns on this invention which achieves the objective mentioned above is a inert powder in which mixed powder by which Cu powder and Ga were mix | blended by the ratio of 85: 15-55: 45 by mass ratio. Cu-Ga alloy powder that has been alloyed by stirring at a temperature of 30 ° C. or higher and 400 ° C. or lower is heat-treated at a temperature of 400 ° C. or higher and 900 ° C. or lower in a vacuum or an inert atmosphere, and then pressed and sintered. It is characterized by that.

  In addition, a Cu—Ga alloy sputtering target according to the present invention that achieves the above-described object is manufactured by the above-described method for manufacturing a Cu—Ga alloy sputtering target.

  In the present invention, a mixed powder in which Cu powder and Ga are blended at a mass ratio of 85:15 to 55:45 is stirred and alloyed at a temperature of 30 ° C. to 400 ° C. in an inert atmosphere. Next, the alloyed Cu—Ga alloy powder is heat-treated at a temperature of 400 ° C. or more and 900 ° C. or less in a vacuum or an inert atmosphere, so that the homogenization reaction of the mixed powder can be sufficiently advanced. High-quality Cu-Ga alloy powder with suppressed generation of Ga liquid phase can be sintered, and defects such as cracks do not occur in the sintered body, and high-quality Cu-Ga alloy sputtering target is produced. can do.

It is a figure explaining the outline | summary of the manufacturing method of the Cu-Ga alloy sputtering target in one embodiment of this invention.

  Below, the manufacturing method of the Cu-Ga alloy sputtering target to which this invention is applied and the Cu-Ga alloy sputtering target obtained by this manufacturing method are demonstrated in detail. Note that the present invention is not limited to the following detailed description unless otherwise specified.

  FIG. 1 is a view for explaining an outline of a method for producing a Cu—Ga alloy sputtering target in one embodiment of the present invention. The manufacturing method of a Cu-Ga alloy sputtering target includes a manufacturing process (A) for manufacturing a Cu-Ga alloy powder, a heat treatment process (B) for heat-treating the Cu-Ga alloy powder, and a Cu-Ga alloy powder after the heat treatment. And a finishing step (D).

  In the method for producing a Cu—Ga alloy sputtering target, the Cu—Ga alloy powder produced in the Cu—Ga alloy powder production step (A) is heated to 400 ° C. or more and 900 ° C. in a vacuum or inert atmosphere in the heat treatment step (B). After heat treatment at the following temperature, pressure is applied in the sintering step (C) to sinter, and a Cu—Ga alloy sputtering target is manufactured in the finishing step (D).

<1. Method for producing Cu-Ga alloy powder>
First, the manufacturing method of the Cu-Ga alloy powder in the manufacturing process (A) of Cu-Ga alloy powder is demonstrated.

(material)
Cu powder and Ga are used as raw materials for the Cu—Ga alloy powder. The purity of the Cu powder and Ga is appropriately selected so as not to affect the characteristics of the CIGS light absorption layer formed from the Cu—Ga alloy sputtering target.

  As the Cu powder, for example, electrolytic Cu powder or atomized Cu powder produced by an electrolytic method or an atomizing method can be used. The electrolytic Cu powder is produced by depositing spongy or dendritic Cu on the cathode by electrolysis in an electrolytic solution such as a copper sulfate solution. As for the atomized Cu powder, spherical or irregular shaped Cu powder is produced by a gas atomization method, a water atomization method, a centrifugal atomization method, a melt extraction method, or the like. In addition, you may use what was manufactured by Cu methods other than these methods.

  The average particle size of the Cu powder is preferably 1 to 300 μm. When the average particle size of the Cu powder is less than 1 μm, special handling for preventing the scattering of the Cu powder is required, the bulk capacity of the Cu powder is increased, the size of the alloy powder manufacturing apparatus is increased, and the cost is increased. A device is required. Further, when the average particle size of the Cu powder exceeds 300 μm, the surface area (BET) of the Cu powder that must be coated with Ga decreases, and the amount of Ga required for the coating also decreases, resulting in an excess. Furthermore, since the liquid phase of unreacted Ga remains, Ga cannot be used effectively. Therefore, by setting the average particle size of Cu powder to 1 to 300 μm, it is not necessary to take measures to prevent scattering of Cu powder, the enlargement of the alloy powder production apparatus can be prevented, and the liquid phase of unreacted Ga can be reduced. It can be reduced, and Ga can be used effectively.

  The average particle size of the Cu powder is obtained by measuring the particle size distribution of the Cu powder by a laser diffraction method, integrating the abundance ratio (volume basis) from the small diameter side, and integrating the abundance ratio over the entire particle diameter. The particle size (D50) is half of the value.

  Ga is a metal having a low melting point (melting point: 29.78 ° C.) and is easily melted by heating. The molten Ga is coated with Cu powder to form a binary alloy. Although there is no restriction | limiting in the shape of Ga, when it is a small piece, weighing is easy. The small piece can be obtained by melting and casting Ga in the vicinity of room temperature and crushing the casting.

(Combination)
Cu powder and Ga are mix | blended in the ratio of 85: 15-55: 45 by mass ratio. When the amount of Ga is 15% by mass or more, uniform coating with Ga becomes possible, and a uniform alloy structure can be obtained when the obtained powder is sintered. Moreover, when the amount of Ga is 45% by mass or less, Cu powders can be prevented from being combined and formed into a lump by a large amount of Ga existing between Cu powders, and the yield of the alloy powder is improved. be able to.

  Moreover, it is preferable that content of Ga is 25-41 mass%. When Ga is 25% by mass or more, Cu powder can be uniformly coated in a short time, and when Ga is 41% by mass or less, Ga coated in a short time can be alloyed. it can. Therefore, a uniform alloy powder can be produced in a short time by setting the Ga content to 25 mass% or more and 41 mass% or less.

(Alloying)
The mixed powder in which Cu powder and Ga are blended in the above-described mass ratio is alloyed by stirring at a temperature of 30 ° C. or higher and 400 ° C. or lower in an inert atmosphere, and as shown in FIG. Is made. Specifically, the Cu powder and Ga pieces weighed at the above-described mass ratio are put into the mixing device 2, the temperature is controlled in the range of 30 ° C. or more and 400 ° C. or less with the heating means 3, and stirring is performed with the stirrer 4. By mixing Cu powder and Ga, Cu—Ga binary alloy powder 1 in which Ga is dispersed on the surface or inside of Cu powder is produced.

  The Cu—Ga alloy powder 1 is considered to be formed through the following process. Ga, which has become liquid beyond the melting point, is uniformly dispersed between Cu powders while becoming small droplets by the shearing motion of mixing. The dispersed Ga droplets adhere to the periphery of the Cu powder, and when the Cu powder and Ga droplets come into contact with each other, the Ga powder begins to diffuse into the Cu powder, and the Ga concentration increases while alloying while forming a Cu-Ga intermetallic compound. The reaction proceeds. At this time, the surface of the Cu—Ga alloy powder 1 is a Cu—Ga intermetallic compound layer having a high Ga concentration, and the central portion is a Cu phase in which pure Cu or Ga is dissolved.

  This mixing of Cu powder and Ga is effective for the progress of a uniform alloying reaction. Moreover, it is considered that the shearing motion of mixing also suppresses the formation of a lump due to the adhesion between the powders. If a lump is generated, voids are generated in the sintered body in a sintering process such as hot pressing, and the density becomes non-uniform.

  For heating for mixing and alloying of Cu powder and Ga, a mixing device 2 in which a stirrer 4 such as a stirring blade or a stirring blade moves in the container can be used. Moreover, you may use rotating container type mixing apparatuses, such as a cylinder, a double cone, and a twin shell. Also, mixing may be strengthened by throwing balls into the container.

  The container material is selected from the viewpoints of heat resistance against heating and suppression of adhesion of Ga and Cu—Ga alloys. Examples of the container include glass containers such as borosilicate glass and quartz glass, ceramic containers such as alumina and zirconia, Teflon resin containers, Teflon-coated containers, and enamel containers.

  The Cu—Ga alloy powder 1 produced in this way is not only excellent in strength and formability, but also because the production temperature is low, the apparatus used for production becomes simple, so the alloy powder can be produced at low cost. It has the advantage that it can be produced.

  Moreover, mixing and alloying of Cu powder and Ga are performed in inert gas atmosphere, such as argon gas and nitrogen gas. By heating and mixing in an inert gas atmosphere, an increase in the oxygen content of the alloy powder can be suppressed.

<2. Manufacturing method of Cu-Ga alloy sputtering target>
Next, the manufacturing method of the sputtering target using the Cu-Ga alloy powder 1 mentioned above is demonstrated. First, the heat treatment step (B) for heat-treating the Cu—Ga alloy powder 1 will be described.

  In manufacturing a Cu—Ga alloy sputtering target, Cu—Ga alloy powder 1 of the Cu—Ga binary alloy has various phases depending on the composition and temperature. It is necessary to determine the conclusion conditions.

(Heat treatment)
The heat treatment of the Cu—Ga alloy powder 1 is performed by putting the Cu—Ga alloy powder 1 in a mold 6 having heat resistance at a high temperature of the hot press apparatus 5. By performing the heat treatment in the hot press apparatus 5, the subsequent sintering step (C) can also be performed in the same hot press apparatus 5. The heat treatment is performed by heating the Cu—Ga alloy powder 1 to 400 ° C. or more and 900 ° C. or less in a vacuum or an inert atmosphere.

  When the heat treatment temperature is less than 400 ° C., the homogenization reaction does not proceed sufficiently and a Ga-rich liquid phase appears locally, and the liquid phase leaks due to subsequent pressure sintering. If the heat treatment temperature is higher than 900 ° C., a liquid phase appears in any composition, and it becomes impossible to produce a sintered body. Therefore, by setting the heat treatment temperature in the range of 400 ° C. or more and 900 ° C. or less, Ga-rich liquid phase does not appear locally, so that liquid phase leakage can be prevented, and the sintered body is sintered in the subsequent sintering step (C). Can be produced.

  Moreover, it is preferable to make it a no-load with respect to the Cu-Ga alloy powder 1, or set it as a pressure of 0.1 Mpa or less in the case of heat processing. When applying a pressure of 0.1 MPa or less to the Cu—Ga alloy powder 1, it is applied by the weight of the upper punch 7 of the hot press device 5. The pressure of 0.1 MPa or less corresponds to the pressure due to the weight of the upper punch 7 of the hot press device 5, and the pressure of no load or 0.1 MPa or less is substantially a pressure on the Cu—Ga alloy powder 1. It is not in the state.

  In the heat treatment, the Cu—Ga alloy powder 1 is unloaded or the pressure is set to 0.1 MPa or less, so that even if a Ga liquid phase appears locally, the liquid phase is pressed by the hot press device 5. A high-quality sintered body can be produced in which the Cu—Ga alloy powder 1 can be sufficiently homogenized without being extruded from the mold, and the composition of Cu and Ga remains unchanged in the subsequent sintering step (C). be able to.

The heat treatment time is preferably 1 hour or more and 8 hours or less. By setting the heat treatment time to 1 hour or longer, it is possible to prevent Cu and Ga from sufficiently diffusing and to leave an unreacted CuGa ₂ phase. By setting the heat treatment time to 8 hours or less, the Cu—Ga alloy sputtering target can be produced at low cost without taking too much time for the production of the Cu—Ga alloy sputtering target. Therefore, by setting the heat treatment time to 1 hour or more and 8 hours or less, the diffusion of Cu and Ga sufficiently proceeds, the unreacted CuGa ₂ phase does not remain, and the Cu—Ga alloy sputtering target obtained by providing the heat treatment step. The Cu—Ga alloy sputtering target can be manufactured without excessively increasing the manufacturing time.

  As described above, the Cu—Ga alloy powder 1 is heat-treated at 400 ° C. or more and 900 ° C. or less in a vacuum or an inert atmosphere before the Cu—Ga alloy powder 1 is sintered, thereby forming Ga at the center of Cu. Diffuses and the appearance of the Ga liquid phase is suppressed.

  Moreover, in this manufacturing method of a Cu-Ga alloy sputtering target, even if the liquid phase of Ga appears, since a liquid phase is not extruded from the hot press apparatus 5, there is no change in the composition of the Cu-Ga alloy powder 1. The homogenization reaction of the Cu-Ga alloy powder 1 can be advanced, and a high-quality sintered body can be produced in the subsequent sintering step (C).

  Furthermore, in the heat treatment, the liquid phase is hot even if a Ga liquid phase appears locally by causing no pressure on the Cu—Ga alloy powder 1 or a pressure of 0.1 MPa or less. The homogenization reaction can proceed without being pushed out from the press die of the press device 5.

  Further, in the heat treatment, by setting the heat treatment time to 1 hour or more and 8 hours or less, the diffusion of Cu and Ga can be sufficiently advanced, and the heat treatment can be performed without excessively increasing the heat treatment time.

(Sintering)
Next, the sintering step (C) in which the Cu—Ga alloy powder 1 is pressed and sintered will be described. For sintering, the heat-treated Cu—Ga alloy powder 1 is sandwiched between the upper punch 7 and the lower punch 8 of the hot press device 5 in a vacuum or an inert gas atmosphere, and the hot press pressure is about 5 MPa to 30 MPa. And pressure sintering. That is, the sintering is performed by a hot press method. According to the hot press method, a high-density sintered body can be obtained at low cost.

  In the sintering, the Cu—Ga alloy powder 1 is not taken out from the hot press apparatus 5 used in the heat treatment, and after the heat treatment, the same hot press apparatus 5 is subsequently subjected to pressure sintering. As a result, there is no need to prepare a separate heat treatment device, heat treatment cooling time is unnecessary, and subsequent press pressure is applied, so there is no need to take measures such as crushing even if the alloy powder is agglomerated, and easy sintering It can be performed. Further, by performing heat treatment and sintering in the same hot press apparatus 5, even if a liquid phase of Ga is generated by the heat treatment, the liquid phase does not leak, so the composition of the Cu—Ga alloy sputtering target changes. Or a decrease in yield.

  Thus, since the Cu—Ga alloy powder 1 is sintered, Ga diffuses into Cu, and thus a uniformly alloyed Cu—Ga alloy sintered body can be obtained.

(Finishing)
In the finishing step (D), the surface of the sintered body of the Cu—Ga alloy obtained in the sintering step (C) is finished to a flat surface by grinding and bonded to a Cu backing plate, thereby forming a Cu—Ga alloy sputtering. You can get a target.

  As mentioned above, in the manufacturing method of a Cu-Ga alloy sputtering target, Cu powder and Ga mix | blended the ratio of 85: 15-55: 45, 30 degreeC or more and 400 degrees C or less in inert atmosphere The Cu—Ga alloy powder that has been agitated and alloyed at a temperature of 5 ° C. is heat-treated at a temperature of 400 ° C. or more and 900 ° C. or less in a vacuum or an inert atmosphere, thereby sufficiently homogenizing the Cu—Ga alloy powder 1. The Cu—Ga alloy sputtering target can be manufactured without causing problems such as cracks in the sintered body. Thereby, in this manufacturing method, a high quality Cu-Ga alloy sputtering target can be obtained.

  In addition, in the manufacturing method of the above-mentioned Cu-Ga alloy sputtering target, although heat processing and sintering were performed with the same hot press apparatus, not only this but heat processing using other heating apparatuses, such as a vacuum heat treatment furnace, is carried out. And sintering may be performed with a hot press apparatus.

  Hereinafter, specific examples to which the present invention is applied will be described, but the present invention is not limited to these examples.

Example 1
In Example 1, a 300 mL porcelain beaker set in a mantle heater and a stirrer in which a glass stirring blade was attached to the porcelain beaker were installed in a glove box in an argon gas atmosphere.

  First, Cu—Ga alloy powder was prepared. Weigh 68.0 g of atomized Cu powder (average particle size 106 μm) and 32.0 g of Ga small pieces, put them into a beaker and heat and mix them in an argon gas atmosphere at 230 ° C. for 45 minutes. -Ga alloy powder was produced.

Next, the Cu—Ga alloy powder was heat-treated. For the heat treatment, a hot press apparatus (manufactured by Daia Vacuum Co., Ltd.) was used, the Cu—Ga alloy powder was put into a graphite press mold having a diameter of 60 mm, and evacuated to a vacuum degree of 5 × 10 ⁻³ Pa. A heat treatment was performed at 700 ° C. for 1 hour in a state where a pressure of 0.1 MPa was applied due to its own weight.

  Next, the Cu—Ga alloy powder after the heat treatment was sintered. After the heat treatment, sintering was performed for 1 hour by applying a pressure of 24.3 MPa while being held at 700 ° C., and a sintered body of a Cu—Ga alloy having a diameter of 60 mm and a thickness of 4.2 mm was produced.

  No cracks were observed in the sintered body taken out from the press mold.

  Further, the Cu—Ga alloy sintered body was subjected to surface grinding, finished to a size of 60 mm in diameter and 3.7 mm in thickness by machining, and bonded to a Cu backing plate to obtain a Cu—Ga alloy sputtering target.

(Example 2)
In Example 2, 55.0 g of atomized Cu powder as a raw material of the Cu—Ga alloy powder, 45.0 g of Ga small pieces were weighed, and the heat treatment temperature was set to 400 ° C. In the same manner as in Example 1, Cu— A sintered body of Ga alloy was prepared. No cracks were found in the sintered body taken out from the press mold. And the Cu-Ga alloy sputtering target was produced similarly to Example 1. FIG.

(Example 3)
In Example 3, a sintered body of Cu—Ga alloy was prepared in the same manner as in Example 1 except that 85.0 g of the atomized Cu powder as a raw material and 15.0 g of Ga small pieces were weighed and the heat treatment temperature was set to 900 ° C. Was made. No cracks were found in the sintered body taken out from the press mold. And the Cu-Ga alloy sputtering target was produced similarly to Example 1. FIG.

(Example 4)
In Example 4, a Cu—Ga alloy sintered body was produced in the same manner as in Example 1 except that the heat treatment time was 8 hours. No cracks were found in the sintered body taken out from the press mold. And the Cu-Ga alloy sputtering target was produced similarly to Example 1. FIG.

(Example 5)
In Example 5, a sintered body of Cu—Ga alloy was produced in the same manner as in Example 1 except that the average particle size of the atomized Cu powder was 1 μm. No cracks were found in the sintered body taken out from the press mold. And the Cu-Ga alloy sputtering target was produced similarly to Example 1. FIG. In addition, about the heat processing, it heat-processed in the hot press apparatus in the state without an upper punch (no load). Then, it cooled to room temperature, the upper punch was set, and pressure sintering was performed.

(Example 6)
In Example 6, a sintered body of Cu—Ga alloy was produced in the same manner as in Example 1 except that electrolytic Cu powder having an average particle size of 300 μm was used as Cu powder. No cracks were found in the sintered body taken out from the press mold. And the Cu-Ga alloy sputtering target was produced similarly to Example 1. FIG.

(Example 7)
In Example 7, a Cu—Ga alloy powder was produced in the same manner as in Example 1. This alloy powder was put into a vacuum heat treatment furnace (manufactured by Tokyo Vacuum Co., Ltd.), evacuated to a vacuum degree of 5 × 10 ⁻³ Pa, and then heat-treated at 700 ° C. for 1 hour in an unloaded state. The alloy powder was agglomerated when it was cooled to room temperature after cooling for 16 hours, and was crushed using a mortar.

The pulverized alloy powder was put into a graphite press mold having a diameter of 60 mm of a hot press apparatus (manufactured by Daia Vacuum Co., Ltd.), evacuated to a vacuum degree of 5 × 10 ⁻³ Pa, 700 ° C., 24.3 MPa, As a result of pressure sintering for 1 hour, a Cu—Ga alloy sintered body having a diameter of 60 mm and a thickness of 3.4 mm was obtained.

  This Example 7 was different from Examples 1 to 6 in which the heat treatment and sintering were performed in the same hot press apparatus, and the heat treatment was performed in a vacuum heat treatment furnace and the sintering was performed in the hot press apparatus.

(Comparative Example 1)
In Comparative Example 1, a sintered body of Cu—Ga alloy was prepared in the same manner as in Example 1 except that the heat treatment before pressurization was not performed, the temperature was increased while pressurization, and sintering was performed at 700 ° C. for 2 hours 30 minutes. Was made. As a result, the sintered body was cracked with the leakage of the liquid phase and could not be used as a sputtering target.

  Table 1 shows the Cu—Ga alloy powders of Examples 1 to 7 and Comparative Example 1, the conditions for heat treatment and pressure sintering, and the yield of the sintered body. The yield of the sintered body is the ratio of the weight of the obtained sintered body to the weight of the prepared Cu—Ga alloy powder, and was determined by (weight of sintered body / Cu—Ga alloy powder weight) × 100. Value.

As shown in Examples 1 to 7 above, Cu powder and Ga are blended at a predetermined ratio and alloyed to obtain a high-quality Cu—Ga alloy powder at a predetermined temperature without any load. And after heat-processing for time, it pressurizes and sinters, A high quality Cu-Ga alloy sintered compact can be produced, without generating a liquid phase and generating a crack.

  On the other hand, in Comparative Example 1, since heat treatment was not performed before sintering as in the example, cracks due to liquid phase leakage occurred, and a sintered body of Cu—Ga alloy could not be produced.

  In Examples 1 to 6, since the heat treatment and sintering of the Cu—Ga alloy powder are performed in the same hot press apparatus, there is almost no change in the weight of the Cu—Ga alloy powder. The rate is higher than 98%. On the other hand, in Example 7, the heat treatment of the Cu—Ga alloy powder is performed in a vacuum heat treatment furnace, the sintering is performed in a hot press apparatus, and the heat treatment and the sintering are performed in separate apparatuses. Since the Cu—Ga alloy powder remained inside, the weight of the Cu—Ga alloy powder was reduced, and the yield of the sintered body was lowered.

  The manufacturing method of the Cu-Ga alloy sputtering target of this invention can be used suitably for manufacturing a high-quality and cheap Cu-Ga alloy target.

Claims (5)

  Cu-Ga alloy powder obtained by alloying mixed powder in which Cu powder and Ga are mixed at a mass ratio of 85:15 to 55:45 at a temperature of 30 ° C. or higher and 400 ° C. or lower in an inert atmosphere. On the other hand, a heat treatment is performed at a temperature of 400 ° C. or higher and 900 ° C. or lower in a vacuum or in an inert atmosphere, and then pressurized to sinter the Cu—Ga alloy sputtering target.   The method for producing a Cu-Ga alloy sputtering target according to claim 1, wherein the heat treatment time is 1 hour or more and 8 hours or less.   The method for producing a Cu-Ga alloy sputtering target according to claim 1 or 2, wherein the Cu powder has an average particle size of 1 µm to 300 µm. The heat treatment and the sintering are performed after the heat treatment in the same hot press apparatus.
The method for producing a Cu-Ga alloy sputtering target according to any one of claims 1 to 3, wherein the heat treatment is performed with no load on the mixed powder or at a pressure of 0.1 MPa or less. .   It manufactures with the manufacturing method of the Cu-Ga alloy sputtering target of any one of Claim 1 thru | or 4, The Cu-Ga alloy sputtering target characterized by the above-mentioned.

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