JP6769332B2 - Sputtering target and its manufacturing method - Google Patents

Description

The present invention relates to a sputtering target and a method for manufacturing the same, and more particularly to a sputtering target used for manufacturing a CIGS type solar cell and a method for manufacturing the same.

The CIGS type solar cell is composed of, for example, a Mo electrode layer which is arranged on a soda lime glass substrate and serves as a positive electrode, and a Cu-In-Ga-Se quaternary alloy layer which is arranged on the Mo electrode layer. The structure is such that a light absorption layer, a buffer layer arranged on the light absorption layer and made of ZnS, CdS, etc., and a transparent electrode layer arranged on the buffer layer and serving as a negative electrode are laminated. ..

As a method for forming the light absorption layer, a method of forming a film by a thin film deposition method is known. Although the light absorption layer (Cu-In-Ga-Se quaternary alloy layer) formed by this method can obtain high energy conversion efficiency, the film formation rate is very slow, so that the cost is high.
Therefore, the light absorption layer is formed by using a sputtering method having a higher film forming speed than the vapor deposition method.

Specifically, for example, an In film is formed by a sputtering method using an In target, and a Cu-Ga binary alloy film is formed on the In film by a sputtering method using a Cu-Ga binary alloy target. A light absorption layer (Cu-In-Ga-Se quaternary alloy layer) is formed by heat-treating a laminated film composed of an In film and a Cu-Ga binary alloy film formed in a Se atmosphere. Is being formed.

In the Cu-Ga binary alloy target, when the Ga content is 30% by mass or more (in other words, when the Ga content is high), a fragile γ phase is generated, and the Cu-Ga binary alloy target has a fragile γ phase. In the process of cutting and finishing the surface of the base material of the Cu—Ga binary alloy target during the manufacturing process, cracks and defects are likely to occur, so that it is difficult to perform the cutting process with high accuracy.

As a technique capable of solving such a problem, for example, there is a technique disclosed in Patent Document 1.
In Patent Document 1, a high Ga-containing Cu-Ga binary alloy powder containing more than 30% by mass of Ga and having a balance of Cu contains pure copper powder or Ga: 15% by mass or less, and the balance is Cu. A low Ga-containing Cu-Ga binary alloy powder composed of Ga: 30 to 60% by mass is blended and mixed so as to have a component composition of Cu in the balance to prepare a mixed powder. High Ga-containing Cu-Ga binary alloy granules by cutting the surface of a hot-pressed body obtained by hot-pressing the powder and containing Ga: 30 to 60% by mass and having a component composition in which the balance is Cu. Disclosed to produce a high Ga-containing Cu-Ga binary alloy sputtering target having a two-phase coexistence structure surrounded by a grain boundary phase composed of a low Ga-containing Cu-Ga binary alloy of Ga: 15% by mass or less. Has been done.

Japanese Unexamined Patent Publication No. 2008-138232

However, in the method for producing a high Ga-containing Cu-Ga binary alloy sputtering target disclosed in Patent Document 1, a low Ga-containing Cu-Ga binary alloy phase and a high Ga-containing Cu-Ga binary alloy phase are used. In order to obtain a two-phase coexisting structure, firing is performed at a low temperature for the purpose of suppressing the reaction of the two phases.

Therefore, it is difficult to produce a high-density sputtering target.
That is, it is difficult to produce a high-density sputtering target by the technique disclosed in Patent Document 1.
Firing at a high temperature is effective for producing a high-density sputtering target, but the fragile γ phase becomes a matrix phase and the workability is significantly reduced.

Therefore, an object of the present invention is to provide a sputtering target capable of performing cutting with high accuracy by suppressing the occurrence of cracks while the fragile γ phase is the parent phase, and a method for producing the same. To do.

To solve the above problems, one according to the aspect of the present invention, Ga: 26 atomic% or more 52 atomic% or less, an In: 1 atomic least 3.5 atomic% or less, Ri the name of Cu and inevitable impurities balance, anti Provided is a sputtering target characterized by a folding strength of 100 MPa or more .

According to the present invention, by adding In in the range of 1 atom or more and 3.5 atom% or less, the occurrence of cracks can be suppressed even in a CuGa alloy containing Ga in an amount of 26 atomic% or more and 52% atom or less. it can.
That is, by adding In, the soft metal In is dissolved in the γ phase, which is a brittle material. Then, the embrittlement of the γ phase is suppressed and the workability is improved, so that the cutting process at the time of manufacturing the sputtering target can be performed with high accuracy.
If the In content is less than one atom, it becomes difficult to obtain the crack suppression effect of the sputtering target by adding In. On the other hand, if the In content is more than 3.5 atomic%, the In solid solution limit in CuGa is exceeded at the sintering temperature of the γ phase, and In leaching occurs. Therefore, it is necessary to lower the sintering temperature, and the density of the sputtering target is lowered.

Further, by setting the bending strength of the sputtering target to 100 MPa or more, the sputtering target is less likely to crack during cutting, so that cutting can be performed with higher accuracy.

In the sputtering target, the average particle size of the CuGa-γ phase may be 100 μm or less.

Making the average particle size of the CuGa-γ phase larger than 100 μm is not very preferable from the viewpoint of easily producing a sputtering target. If the average particle size of the CuGa-γ phase is larger than 100 μm, cracks and chipping are likely to occur along the grain boundaries during target processing.
Therefore, by setting the average particle size of the CuGa-γ phase to 100 μm or less, a sputtering target can be easily manufactured.

In the sputtering target, the amount of increase in the lattice spacing of the CuGa-γ phase after In addition may be 0.05% or more.

As described above, by setting the increase amount of the lattice spacing of the CuGa-γ phase to 0.05% or more, the lattice spacing is widened by the solid solution of In into CuGa, so that the workability can be improved.

The relative density of the sputtering target may be 90% or more.

By setting the relative density to 90% or more in this way, it is possible to prevent cracking during cutting and use.

In order to solve the above problems, according to another viewpoint of the present invention, Ga: 26 atomic% or more and 52 atomic% or less, In: 1 atom or more and 3.5 atomic% or less, and the balance is Cu and Cu- consisting of unavoidable impurities. A step of producing a Cu-In-Ga alloy powder by atomizing a molten In-Ga alloy, a step of producing a Cu-In alloy powder by atomizing a molten Cu-In alloy, or a Cu- A step of producing a Cu-Ga alloy powder by atomizing a molten metal of Ga alloy, a step of producing a sintered body by sintering the Cu-In-Ga alloy powder to produce a sintered body, or a sintered body production step in which the composition is Ga. : The Cu-In-Ga alloy powder or the Cu-In alloy powder or the Cu-In alloy powder so that 26 atomic% or more and 52 atomic% or less, In: 1 atom or more and 3.5 atomic% or less, and the balance becomes Cu and unavoidable impurities Provided is a method for producing a sputtering target, which comprises a sintered body manufacturing step of manufacturing a sintered body by sintering the CuGa atomized powder or a mixed powder mixed with Cu powder. ..

According to the present invention, it is possible to reduce cracks in cutting by a simple method in which Ga is composed of 26 atomic% or more and 52 atomic% or less, In: 1 atom or more and 3.5 atomic% or less, and the balance is Cu and unavoidable impurities. Sputtering target can be manufactured.

Further, by using the Cu—In alloy powder, the Cu—Ga alloy powder, or the Cu powder, the composition of the sputtering target can be easily adjusted to a desired composition.

In the method for manufacturing a sputtering target, there may be a step of cutting the surface of the sintered body after the sintered body manufacturing step.

As a result, it is possible to suppress the occurrence of cracks in the sintered body when the sintered body that is the base material of the sputtering target is cut.

According to the present invention, by suppressing the occurrence of cracks by a simple method, it is possible to accurately perform the cutting process at the time of manufacturing the sputtering target.

It is a figure which shows the amount of increase in the lattice plane spacing of CuGa-γ phase (330) by the target surface X-ray diffraction measurement of Examples 1, 2 and 4 and Comparative Examples 3, 4, 5, 6. It is a photograph of the upper surface side of a sample for chipping evaluation after grinding process fixed to a fixing member. It is a photograph for demonstrating the length of the chipped part, and is an enlarged photograph of the part surrounded by the region A shown in FIG. It is a figure which shows the composition analysis result of the target surface of Example 4. FIG.

Hereinafter, embodiments to which the present invention is applied will be described in detail.

<Sputtering target>
The sputtering target (In-added CuGa target) of the embodiment of the present invention comprises 26 atomic% or more and 52 atomic% or less of Ga: Ga, In: 1 atom or more and 3.5 atomic% or less, and the balance is Cu and unavoidable impurities. It is composed.
If the content of In is less than one atom, it becomes difficult to obtain the effect of suppressing cracking of the sputtering target by adding In. On the other hand, if the In content is more than 3.5 atomic%, the solid solution limit of In is exceeded at the sintering temperature of the γ phase, and In leaching occurs. Therefore, it is necessary to lower the sintering temperature, and the density of the sputtering target is lowered.

In the sputtering target, In may be dissolved in at least the γ phase of CuGa.
In a Cu-Ga alloy containing Ga of 26 atomic% or more and 52 atomic% or less (in other words, high concentration Ga), a brittle γ phase is likely to be formed, and if many such γ phases are present, cracks occur during cutting. It may cause it.
Therefore, by dissolving In in the γ phase of CuGa, it is possible to suppress the occurrence of cracks during cutting.
Further, even if the In single phase is present at the grain boundary or the like, the occurrence of cracks can be suppressed during the cutting process.

Further, in the sputtering target, the average particle size of the CuGa-γ phase may be 100 μm or less.

Making the average particle size of the CuGa-γ phase larger than 100 μm is not very preferable from the viewpoint of easily producing a sputtering target. If the average particle size of the CuGa-γ phase is larger than 100 μm, cracks and chipping are likely to occur along the grain boundaries during target processing.
Therefore, by setting the average particle size of the CuGa-γ phase to 100 μm or less, a sputtering target can be easily manufactured.

Further, in the sputtering target, the bending strength may be 100 MPa or more.
By setting the bending strength of the sputtering target to 100 MPa or more in this way, the sputtering target is less likely to crack during cutting, so that cutting can be performed with higher accuracy.

Further, the relative density of the sputtering target may be 90% or more.
In this way, by setting the bending strength of the sputtering target to 100 MPa or more, it is possible to prevent cracking during cutting and use.

According to the sputtering target of the present embodiment, by adding In in the range of 1 atom or more and 3.5 atom% or less, cracks occur even in the CuGa alloy containing 26 atom% or more and 52 atoms or less of Ga. Can be suppressed.
That is, by adding In, the soft metal In is dissolved in the γ phase, which is a brittle material, and the workability of the γ phase is improved, so that the cutting process at the time of manufacturing the sputtering target can be performed with high accuracy. ..

<Manufacturing method of sputtering target>
The method for producing a sputtering target is to atomize a molten Cu-In-Ga alloy containing Ga: 26 atomic% or more and 52 atomic% or less, In: 1 atom or more and 3.5 atomic% or less, and the balance consisting of Cu and unavoidable impurities. Then, the Cu-In alloy powder is produced by the step of producing the Cu-In-Ga alloy powder (hereinafter referred to as "Cu-In-Ga alloy powder production process") or by atomizing the molten metal of the Cu-In alloy. (Hereinafter referred to as "Cu-In alloy powder manufacturing step") or a step of producing Cu-Ga alloy powder by atomizing a molten Cu-Ga alloy (hereinafter referred to as "Cu-Ga alloy powder manufacturing step"). The Cu-In-Ga alloy powder is sintered to produce a sintered body. The sintered body manufacturing step or composition is Ga: 26 atomic% or more and 52 atomic% or less, In: 1 atomic or more. The Cu—In—Ga alloy powder, the Cu—In alloy powder, the CuGa atomize powder, or a mixed powder mixed with the Cu powder is baked so that the balance is Cu and unavoidable impurities in an amount of 5 atomic% or less. It has a sintered body manufacturing step of manufacturing a sintered body by tying.
Further, the method for manufacturing a sputtering target may include a step of cutting the surface of the sintered body after the sintered body manufacturing step.

Here, an example of a method for manufacturing a sputtering target will be described.
First, in the Cu—In—Ga alloy powder manufacturing process, a Cu—Ga binary alloy raw material, a high-purity Cu raw material (for example, purity of 99.9% or more), and a high-purity In raw material (for example, purity) 99.9% or more) and prepare.
Next, the above three kinds of raw materials are charged into the carbon crucible so that Ga: 26 atomic% or more and 52 atomic% or less, In: 1 atom or more and 3.5 atomic% or less, and the balance is Cu and unavoidable impurities. Next, a molten metal of Cu—In—Ga alloy is prepared by melting the above three kinds of raw materials in the carbon crucible at high frequency.
Then, the molten Cu—In—Ga alloy is atomized (for example, gas atomized) to prepare a Cu—In—Ga alloy powder. Gas atomization can be performed, for example, by blowing a high-pressure gas of argon.

Next, in the sintered body manufacturing step, the Cu—In—Ga alloy powder is sintered by hot pressing to produce a hot pressed body which is a sintered body having the composition of the sputtering target described above. The hot press can be performed under the treatment conditions of, for example, an argon atmosphere as the treatment atmosphere, a pressure of 196 MPa, a heating temperature of 740 ° C., and a holding time of 1 hour.
Then, the surface of the hot-pressed body is machined to manufacture the above-mentioned sputtering target.

According to the method for manufacturing a sputtering target described above, a simple method is used to perform a cutting process in which Ga: 26 atomic% or more and 52 atomic% or less, In: 1 atom or more and 3.5 atomic% or less, and the balance is Cu and unavoidable impurities. It is possible to manufacture a sputtering target capable of reducing cracking in the area.

Here, another example of a method for manufacturing a sputtering target will be described.
First, in the Cu-In alloy powder manufacturing step, Cu is used in the same manner as the Cu-In-Ga alloy powder manufacturing step described above, except that a Cu-In alloy is used instead of the Cu-In-Ga alloy. -In alloy powder is prepared.
Next, in the mixed powder preparation step, Cu was used using a ball mill so that the composition was Ga: 26 atomic% or more and 52 atomic% or less, In: 1 atom or more and 3.5 atomic% or less, and the balance was Cu and unavoidable impurities. A mixed powder is prepared by mixing the −In alloy powder, the Cu powder, and the CuGa atomized powder.

Next, in the sintered body manufacturing step, a hot-pressed body which is a sintered body is manufactured by the same method as the sintered body manufacturing step of the above-mentioned sputtering target manufacturing method.
Then, the surface of the hot-pressed body is machined to manufacture the above-mentioned sputtering target.

According to the method for manufacturing a sputtering target described above, Ga: 26 atomic% or more and 52 atomic% or less, In: 1 atom or more and 3.5 atomic% or less, and the balance is Cu and unavoidable impurities to reduce cracking during cutting. Possible sputtering targets can be manufactured.
Further, by using the Cu—In alloy powder and the Cu powder, the composition of the sputtering target can be easily adjusted to a desired composition.

Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to such specific embodiments, but within the scope of the gist of the present invention described within the claims. Various modifications and changes are possible.

Hereinafter, Comparative Examples and Examples will be described, but the present invention is not limited to the following Examples.

(Preparation of sputtering target)
Using the above-mentioned method for producing a sputtering target, the sputtering targets of Comparative Examples 1 to 7 and Examples 1 to 8 having the compositions shown in Table 1 were prepared. Comparative Examples 1 and 3 used Cu—Ga alloy powder, and Comparative Examples 2 and 4 to 6 and Examples 1 to 6 used Cu—In alloy powder, CuGa alloy powder and Cu powder. Details are shown in Table 2.
At this time, the average particle size of the Cu—In alloy powder was 18 μm, the average particle size of the 99.9% pure Cu powder was 20 μm, and the average particle size of the CuGa atomized powder was 23 μm.
The hot press conditions for sintering the mixed powder were a pressure of 196 MPa and a temperature of 550 to 830 ° C. for 1 hour in vacuum.

(Anti-folding strength)
For the bending strength, after processing each sputtering target to 3 × 4 × 40 mm, the three-point bending strength was measured based on the JIS R1601 standard. The results are shown in Table 3.

(Average particle size of γ phase of CuGa)
Debris is collected from each sputtering target and the debris is filled with resin. Next, wet polishing is performed so that the portion of the debris exposed from the resin becomes a flat surface.
Next, using JXA-8500, which is an EPMA (electron probe microanalyzer) manufactured by JEOL Ltd., the surface distribution (mapping) of each element (specifically, Cu, Ga, In) on the flat surface of each fragment is measured. Was done.

The measurement conditions at this time are an acceleration voltage of 15 kV, an irradiation current of 50 nA, a scan type of one direction, pixels (X, Y) = (240, 180), and spot size (X, Y) = (0.1 μm, 0). .1 μm), and the measurement time was 10 ms.
Then, from the obtained mapping image, the average particle size of the γ phase of CuGa of each sputtering target was obtained. As a method for calculating the average particle size, a diagonal line was drawn on a mapping image of × 200 times, and the number of γ-phase particles in contact with the diagonal line was counted to calculate the average particle size. The results are shown in Table 3.

(Lattice plane spacing)
Using SA-HF3XRD, which is an X-ray diffractometer manufactured by Rigaku Co., Ltd., the lattice spacing of the γ-phase (330) plane having a strong diffraction intensity of the sputtering target was measured. As the measurement conditions, the measurement step width 2θ was set to 0.02 degrees by the concentration method using X-rays (wavelength 1.5418 Å) of CuKα rays, and Examples 1, 2 and 4 and Comparative Examples 3, 4, 5 were set. X-ray diffraction measurement of the target surface of No. 6 was performed. The results are shown in Table 3 and FIG.
The grid plane spacing 0.2059 nm calculated from the peak derived from the (330) plane described in PDF card number: 00-058-0251 was used as the reference grid plane spacing, and the amount of increase in the grid plane spacing was calculated by the following formula. ..
Increased amount of grid spacing (%) = (measured grid spacing-reference grid spacing) ÷ reference grid spacing x 100

Focusing on FIG. 1, in the measurement of Comparative Example 3 in which the amount of In added was 0 atomic% and the amount of Ga was 30 atomic%, the amount of increase in lattice spacing was 0.17% and the analysis error was 0.05%. Met.
In the case of Example 1 in which the amount of In added was 1 atomic% and the amount of Ga was 30 atomic%, it was confirmed that the amount of increase in lattice spacing was 0.28%, which was larger than the analysis error.
With the addition of In, the lattice spacing of the γ phase (330) plane of CuGa is widened, which is due to the fact that the In atom is larger than the Ga atom, and a part of the Ga atom is replaced with the In atom. It is presumed that there is, or that In has invaded CuGa.

Then, in consideration of the analysis error, if the amount of increase in the lattice spacing was 0.23% or more, it could be determined that the lattice spacing was widened due to the solid solution of In into CuGa, and it was found that the workability was further improved. Further, in the case of Comparative Example 6 in which the amount of In added was 5 atomic% and the amount of Ga was 30 atomic%, the expansion of the lattice spacing was saturated because the In solid solution limit of the CuGa-γ phase was exceeded. It is probable that melting started at the time of HP.

(Relative density evaluation method)
The dimensional density was measured using a caliper, and it was determined whether the relative density was 90% or more. The theoretical density for calculating the relative density was calculated from the ratio of Ga / (Cu + Ga) using the following formula.
When x = Ga / (Cu + Ga) and 0 ≦ x ≦ 0.17, the theoretical density d = 8.75 g / cm ³ . When 0.17 <x <0.22, the theoretical density d = (0.22-x) / (0.22-0.17) × 8.75 + (0.05- (0.22-x)) / (0.22-0.17) × 8.64 g / cm ³ . When x = 0.22, the theoretical density d = 8.64 g / cm ³ . When 0.22 <x <0.30, the theoretical density d = (0.30-x) / (0.30-0.22) × 8.64+ (0.08- (0.30-x)) / (0.30-0.22) × 8.44 g / cm ³ . When 0.30 ≦ x ≦ 0.41, the theoretical density d = 8.44 g / cm ³ . When 0.41 <x <0.54, the theoretical density d = (0.665-x) / (0.665-0.41) × 8.44 + (0.255- (0.665-x)) / (0.665-0.41) × 7.21 g / cm ³ .

(Chip evaluation)
Next, a sample for chipping evaluation was cut out from the sputtering targets of Comparative Examples 1 to 7 and Examples 1 to 8.

FIG. 2 is a photograph of the upper surface side of the chip evaluation sample fixed to the fixing member after grinding.
Next, as shown in FIG. 2, the fixing members 12 to 15 are chipped and evaluated from four directions so as to place the chipping evaluation sample 10 on the stage 11 with the surface 10a of the chipping evaluation sample 10 facing upward and sandwich the chipping evaluation sample 10. The position of the chip evaluation sample 10 was fixed by bringing it into contact with the sample 10.
Next, the surface 10a of the chipping evaluation sample 10 shown in FIG. 2 was cut using a lathe MS850G (model number) manufactured by Mori Seiki Seisakusho Co., Ltd. As the conditions for cutting, a cutting tool feed of 0.48 mm / rotation, a rotation speed of 75 rpm, and a depth of cut of 0.3 mm were used.

Then, the case where the length of the chipped portion of the evaluation sample 10 after cutting was less than 1 mm was evaluated as good, and the state of 1 mm or more was evaluated as defective. The evaluation results are shown in Table 1.

Further, the length of the chipped portion was evaluated by scanning in the X direction or the Y direction using a digital counter of an optical microscope.

FIG. 3 is a photograph for explaining the length of the chipped portion, and is an enlarged photograph of the portion surrounded by the region A shown in FIG.
As shown in FIG. 3, the length from the chipping start position to the chipping end position is the length of the chipped portion. The results are shown in Table 3.

(In melted out)
After hot pressing, it was confirmed whether there was leaching from the mold.

(Mother)
SA-HF3XRD, an X-ray diffractometer manufactured by Rigaku Corporation, was used, and the phase having the highest main peak intensity of the CuGa crystal phase was used as the parent phase.

(Composition analysis of target surface)
The composition of the target surface of Example 4 was analyzed using JXA-8500F (model number), which is an EPMA manufactured by JEOL Ltd. The result is shown in FIG.
With reference to FIG. 4, it was confirmed from the four image data that In was uniformly dispersed over the entire observation area.

(Summary of evaluation results)
In Comparative Example 1, since the Ga content was as low as 20 atomic%, the matrix phase of CuGa became the ζ phase and cracking of the target did not occur. Therefore, it did not break when the anti-folding strength was measured and could not be measured.
In Comparative Example 2, the Ga content was as high as 55 atomic%, and the melting point of CuGa decreased in the high Ga region. Therefore, it was necessary to lower the firing temperature for the purpose of preventing leaching. Therefore, the firing does not proceed and the relative density decreases, so that chipping is easy, the length of the chipped portion becomes longer than 1 mm, and the evaluation of chipping is NG.
In Comparative Example 3, since In was not added, the effect of suppressing the chipping of the γ phase could not be obtained. As a result, the length of the chipped portion became longer than 1 mm, and the evaluation of the chipped portion was NG.
In Comparative Example 4, the amount of In added was 0.1 atomic%. For this reason, the effect of suppressing chipping of the γ phase could not be obtained, the length of the chipped portion became longer than 1 mm, and the evaluation of chipping was NG.
In Comparative Example 5, the amount of In added was 0.5 atomic%. For this reason, the effect of suppressing chipping of the γ phase could not be obtained, the length of the chipped portion became longer than 1 mm, and the evaluation of chipping was NG.
In Comparative Example 6, the amount of In added was 5 atomic%, which was larger than 3.5 atomic%. For this reason, the solid solution limit of In by CuGa was exceeded, and In was leached out at the γ-phase firing temperature.
In Comparative Example 7, since the amount of In added was 5 atomic%, the firing temperature was lowered in order to suppress the dissolution of In. As a result, the sintering of CuGa was not promoted, and the relative density and the bending strength were lowered, so that chipping became easier. Then, the length of the chipped portion became longer than 1 mm, and the evaluation of the chipped portion was NG.
On the other hand, in Examples 1 to 8 in which Ga: 26 atomic% or more and 52 atomic% or less, In: 1 atom or more and 3.5 atomic% or less, and the balance is Cu and unavoidable impurities, the bending strength is 100 MPa or more and CuGa. The average particle size of the −γ phase is 100 μm or less, the lattice spacing of the CuGa−γ phase increases monotonically with the increase in the amount of In added, the relative density is 90% or more, and the length of the chipped portion. It was confirmed that the target was a good target with a thickness of less than 1 mm, good cutting results, and no leaching of In.

10 ... Sample for chipping evaluation, 10a ... Surface, 11 ... Stage, 12 to 15 ... Fixing member, A ... Region

Claims (6)

Ga: 26 atomic% or more 52 atomic% or less, an In: 1 atomic least 3.5 atomic% or less, Ri the name of Cu and inevitable impurities balance,
A sputtering target having a bending strength of 100 MPa or more . The sputtering target according to claim 1 , wherein the average particle size of the CuGa-γ phase is 100 μm or less. The sputtering target according to claim 1 or 2 , wherein the amount of increase in the lattice spacing of the CuGa-γ phase is 0.23% or more. The sputtering target according to any one of claims 1 to 3, wherein the relative density is 90% or more. Ga: Cu-In-Ga by atomizing a molten Cu-In-Ga alloy consisting of 26 atomic% or more and 52 atomic% or less, In: 1 atom or more and 3.5 atomic% or less, and the balance consisting of Cu and unavoidable impurities. A step of producing an alloy powder, a process of producing a Cu-In alloy powder by atomizing a molten Cu-In alloy, or a process of atomizing a molten metal of a Cu-Ga alloy to produce a Cu-Ga alloy powder. And the process to do
A sintered body manufacturing step of sintering the Cu-In-Ga alloy powder to prepare a sintered body, or a composition of Ga: 26 atomic% or more and 52 atomic% or less, In: 1 atomic or more and 3.5 atomic% or less. By sintering the Cu—In—Ga alloy powder, the Cu—In alloy powder, the CuGa atomize powder, or the mixed powder mixed with the Cu powder so that the balance becomes Cu and unavoidable impurities. The sintered body manufacturing process for manufacturing the sintered body and
A method for producing a sputtering target, which comprises. The method for manufacturing a sputtering target according to claim 5 , further comprising a step of cutting the surface of the sintered body after the sintered body manufacturing step.