JP2020164958A - Sputtering target, manufacturing method of sputtering target, manufacturing method of sputtered film, and manufacturing method of solar cell - Google Patents

Abstract

To provide an inexpensive sputtering target suitable for obtaining an In alloy film.SOLUTION: A sputtering target 100 includes a backing plate 130, a first target material 110 joined onto the backing plate 130 through a first solder material 120, and a second target material 112 joined though a second solder material 122, in which the first target material 110 is formed of In containing Cu as much as 0-10,000 mass ppm, and the second target material 112 is formed of Ag.SELECTED DRAWING: Figure 1

Description

The present invention relates to a sputtering target, a method for manufacturing a sputtering target, a method for manufacturing a sputtering film, and a method for manufacturing a solar cell.

Mass production of CIGS-based solar cells with high conversion efficiency as thin-film solar cells is progressing. As a method for producing the CIGS layer, which is the light absorption layer, for example, a thin-film deposition method is known.

Non-Patent Document 1 proposes high conversion efficiency by adding Ag to the light absorption layer of a CIGS solar cell. However, in Non-Patent Document 1, it must be produced by simultaneously vapor-depositing multi-element alloys such as In, Ag, and Ga by vacuuming, and the film thickness distribution over a relatively wide area is uneven. Therefore, the thin-film deposition method has problems of high cost and low productivity.

On the other hand, in order to obtain a uniform film in a wider area than the vapor deposition method, a method of forming by a sputtering method has been proposed. As a sputtering method, for example, a Cu-Ga film is formed by sputtering using a Cu-Ga target, and an In film is formed by sputtering on the Cu-Ga film using an In sputtering target. After that, there is a method of forming a Cu-In-Ga-Se quaternary alloy film by heat-treating the obtained laminated film composed of the In film and the Cu-Ga alloy film in a Se atmosphere.

For example, in Patent Document 1, a backing plate, an indium-tin brazing material, and an indium target are laminated in this order, and a thickness range of 2.5 to 3.0 mm from the indium-tin brazing material side surface of the indium target. A laminated structure having a tin concentration of 5 wtppm or less has been proposed.

In recent years, when forming a sputter film using an In target, an In alloy target in which Ag or the like is added to the In target has been required in order to improve power generation efficiency. For example, in Patent Document 2, it is a silver alloy material, which contains 65-95% by weight of silver and 5-35% by weight of indium based on the total weight, has a solid-liquid coexistence region, and has metal elongation. A silver alloy material characterized in that the ratio is 60%, the yield strength is 58 MPa, and the ultimate tensile strength is 300 MPa has been proposed.

Japanese Unexamined Patent Publication No. 2013-067831 Japanese Unexamined Patent Publication No. 2017-008408

Kihwan Kim, 5 outsiders, "Ag incorporation in low-temperature grown Cu (In, Ga) Se2 solar cells using Ag precursor layers", Solar Energy materials & Solar Cells, Netherlands, March 2016, Vol. 146, p. 114-120

However, in Patent Document 2, a so-called synthesis furnace is required to put the initial product of the silver-indium alloy into a vacuum apparatus and perform annealing treatment to form a silver alloy material containing indium, and further, after using the target, the indium raw material , Can be expensive to refine into silver raw materials.

Further, since the amount of Ag to be added to the CIGS light absorption layer is very small, when one or more of the In targets normally used in several sheets / set are changed to the target of Ag alone, Even if the power during sputtering is adjusted, the Ag concentration contained in the CIGS light absorption layer may be too high. Therefore, in the production of the CIGS light absorption layer, it is difficult to control the Ag concentration unless an In alloy target to which Ag is added is used.
From the above, it is considered that there is still room for improvement in the sputtering target because the In alloy film is formed on the substrate.

Therefore, an object of the present invention is to provide a sputtering target suitable for obtaining a laminated film of In and Ag at low cost in one embodiment. Another object of the present invention is to provide a method for manufacturing the sputtering target in another embodiment. Another object of the present invention is to provide a method for producing a sputtering film using the sputtering target in another embodiment. Further, in another embodiment of the present invention, In, Ag, Cu, Ga and Se are combined by laminating the In and Ag laminated film obtained by the sputtering target and the CuGa film and seleniumizing them. , It is an object of the present invention to provide a method for manufacturing a solar cell capable of obtaining a CIGS light absorption layer.

That is, in one aspect, the present invention has a backing plate, a first target material bonded to the backing plate via a first brazing material, and a second target material bonded to the backing plate via a second brazing material. The first target material is a sputtering target formed of In containing 0 to 10000 mass ppm of Cu, and the second target material is formed of Ag. ..

In one embodiment of the sputtering target according to the present invention, the melting point of the first brazing material is 150 ° C. or lower.

In one embodiment of the sputtering target according to the present invention, the first brazing material is formed of at least one selected from the group consisting of InSn alloys, InBi alloys, and InZn alloys.

In one embodiment of the sputtering target according to the present invention, the InSn alloy contains 10 to 60% by mass of Sn, and the balance is In and unavoidable impurities.

In one embodiment of the sputtering target according to the present invention, the second brazing material is formed of an In or InSn alloy.

In one embodiment of the sputtering target according to the present invention, at least one or more third target materials bonded to the backing plate via a third brazing material are further provided.

In one embodiment of the sputtering target according to the present invention, the third target material is formed of the same material as the first target material.

In one embodiment of the sputtering target according to the present invention, the ratio (S _A / S) of the area (S _B ) of the main surface of the second target material to the area (S _A ) of the main surface of the first target material. _B ) is 1/99 to 99/1.

Further, in another aspect, the present invention is a method for manufacturing any of the above sputtering targets, in which the second target material is bonded onto the backing plate via a molten second brazing material. The first target material includes a first joining step and a second joining step of joining the first target material on the backing plate via a melted first brazing material. , Cu is formed of In containing 0 to 10000 mass ppm of Cu, and the second target material is Ag, which is a method for producing a sputtering target.

In one embodiment of the method for manufacturing a sputtering target according to the present invention, in the first joining step, the second target material is joined onto the backing plate via the second brazing material. The temperature of the second brazing material is in the range of 157 to 250 ° C.

In one embodiment of the method for manufacturing a sputtering target according to the present invention, in the second joining step, the first target material is joined onto the backing plate via the first brazing material. The temperature of the first brazing material is in the range of 120 to 155 ° C.

In one embodiment of the method for manufacturing a sputtering target according to the present invention, the second joining step is carried out after the first joining step.

Further, in another aspect, the present invention is a method for producing a sputtered film, which comprises a step of obtaining a sputtered film by a sputtering method using any of the above sputtering targets.

Further, in another aspect, the present invention is a method for manufacturing a solar cell, which comprises a step of manufacturing a solar cell using the sputtered film obtained by the above-mentioned method for manufacturing a sputtered film.

The sputtering target according to one embodiment of the present invention is suitable for obtaining an In alloy film at low cost.

(A) is a schematic plan view for explaining one embodiment of the sputtering target according to the present invention, and (B) is a schematic cross-sectional view taken along the cutting line I-I of (A). .. It is a schematic plan view for demonstrating one Embodiment of the sputtering target which concerns on this invention. (A) is a schematic plan view for explaining another embodiment of the sputtering target according to the present invention, and (B) is a schematic sectional view taken along line III-III of (A). is there. It is a flow figure for demonstrating one Embodiment of the manufacturing method of the sputtering target which concerns on this invention. It is a schematic cross-sectional view for demonstrating the arrangement of the target material provided in the sputtering target in Examples 1-5 and Comparative Example 1. It is a conceptual diagram for demonstrating the method of measuring the warp of a sputtering target in Examples 1-5 and Comparative Example 1.

Hereinafter, the present invention is not limited to each embodiment, and the constituent elements can be modified and embodied without departing from the gist thereof. In addition, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in each embodiment. For example, some components may be removed from all the components shown in the embodiments. Further, the components of different embodiments may be combined as appropriate.

[1. Sputtering target]
FIG. 1A is a schematic plan view for explaining an embodiment of a sputtering target according to the present invention, and FIG. 1B is a schematic view taken along line I-I of FIG. 1A. Cross-sectional view. FIG. 2 is a schematic plan view for explaining one embodiment of the sputtering target according to the present invention. FIG. 3 (A) is a schematic plan view for explaining another embodiment of the sputtering target according to the present invention, and FIG. 3 (B) is the cutting line III-III of FIG. 3 (A). It is a schematic cross-sectional view.

In one embodiment, the sputtering target 100 according to the present invention includes a first target material 110, a second target material 112, and a first brazing material, as shown in FIGS. 1 (A) and 1 (B). It includes 120, a second brazing material 122, and a backing plate 130. Hereinafter, each configuration will be described with reference to the drawings.

The first target material 110 is joined onto the backing plate 130 via the first brazing material 120, and the second target material 112 is joined via the second brazing material 122. Further, by arranging the first target material 110 and the second target material 112, a laminated structure of the component of the first target material 110 and the component of the second target material 112 is formed on the substrate passing directly above. Can be done. More specifically, the side surface of the first target material 110 is in contact with the side surface of the second target material 112, but the first target material 110 and the first target material 110 in the width direction W are prevented so that the backing plate 130 is not sputtered. The target material 112 of 2 may be separated by 1.0 mm or less. In the present specification, the direction perpendicular to the line (tangent line) generated by contacting the side surface of the first target material 110 and the side surface of the second target material 112 is defined as the width direction W.

The first target material 110 is formed of In containing Cu in an amount of 0 to 10000 mass ppm. The Cu content in the first target material 110 is preferably 10 mass ppm or more, more preferably 100 mass ppm or more, and more preferably 500 mass ppm or more, from the viewpoint of making the crystal grains fine. It is more preferable to have. The Cu content in the first target material 110 is preferably 5000 mass ppm or less, more preferably 3000 mass ppm or less, and 1500 mass ppm or less from the viewpoint of not increasing arcing during sputtering. It is more preferable to have. The first target material 110 may further contain unavoidable impurities in addition to In and Cu. The content as an unavoidable impurity is typically 100 mass ppm or less, and more typically 50 mass ppm or less. The lower limit is not particularly specified, but typically contains 10% by mass or more of gas components such as oxygen and carbon. The method for producing the target material of the In—Cu alloy is as follows. Cu is added to the dissolved In so as to have the above-mentioned concentration to obtain a target material formed by containing Cu in In which can cause recrystallization during sufficient plastic working at room temperature. Then, the recrystallization of the target material is promoted by performing the rolling process in which the thickness reduction rate of the target material is 10 to 80%. By doing so, the crystal structure of the target material becomes fine, so that the crystal grains of the produced target material can be made fine. The average crystal grain size of the target material of the In—Cu alloy may be 3000 μm or less, 1000 μm or less, and is, for example, 10 to 500 μm from the viewpoint of making the sputter film homogeneous.
In the present specification, the average crystal grain size can be measured by the following method. The sputtered surface is electropolished or etched with an acid to make the grain boundaries easier to see. Then, a grain boundary map is prepared by EBSP (Electron Backscattering Pattern, Electron Back Scattering Pattern), and the number (N) of crystal grains existing in a field of view of 1800 × 3500 μm is counted. Regarding the crystal grain boundaries, if the orientations of adjacent crystal grains deviate by 2 ° or more, the boundary is treated as the crystal grain boundaries. Crystal grains existing across the boundary of the region are treated as 0.5. The average area (s) of crystal grains is calculated by dividing the area of the measurement target region (S = 1250 mm ² ) by the number of crystal grains (N). Assuming that the crystal grains are spheres, the average crystal grain size (A) is calculated by the following formula (1).
A = 2 (s / π) ^1/2 ... Equation (1)

The melting point of the first brazing material 120 may be lower than the melting point of the first target material 110, for example, preferably 150 ° C. or lower, more preferably 140 ° C. or lower, and 130 ° C. or lower. Is more preferable. The melting point of the first brazing material 120 is, for example, preferably 110 ° C. or higher, more preferably 115 ° C. or higher, and even more preferably 120 ° C. or higher. Further, the first brazing material 120 is preferably formed of an In alloy, and is selected from the group consisting of an InSn alloy, an InBi alloy, and an InZn alloy from the viewpoint that the melting point is lower than that of the first target material 110. It is more preferable that it is formed of at least one type of alloy. Further, it is preferable that these InSn alloys contain 10 to 60% by mass of Sn, and the balance is In and unavoidable impurities. The Sn content in the InSn alloy is preferably 10% by mass or more, more preferably 30% by mass or more, still more preferably 40% by mass or more, from the viewpoint of lowering the melting point as compared with In. .. The Sn content in the InSn alloy is preferably 60% by mass or less, more preferably 57% by mass or less, still more preferably 55% by mass or less, from the viewpoint of lowering the melting point as compared with In. , Typically 50% by mass (melting point 120 ° C.) is used.

The second target material 112 is made of Ag from the viewpoint of improving the power generation efficiency of the CIGS-based solar cell. Ag is preferably formed with a purity of 99.9% by mass to 99.99% by mass from the viewpoint of preventing the influence of impurities. The second target material 112 may further contain unavoidable impurities in addition to Ag. The content as an unavoidable impurity is typically 1000 mass ppm or less, and more typically 500 mass ppm or less. The lower limit is not particularly specified, but typically contains 10% by mass or more of gas components such as oxygen and carbon.

The melting point of the second brazing material 122 may be lower than the melting point of the second target material 112 and higher than the melting point of the first brazing material 120, preferably 200 ° C. or lower, preferably 180 ° C. The temperature is more preferably 160 ° C. or lower, and further preferably 160 ° C. or lower. The melting point of the second brazing material 122 is, for example, preferably 140 ° C. or higher, more preferably 145 ° C. or higher, and even more preferably 150 ° C. or higher. Further, the second brazing material 122 is preferably formed of In or InSn alloy, is relatively soft, and is formed of In from the viewpoint of great relaxation of stress due to cooling during bonding and heat during sputtering. Is more preferable. As a result, when the first target material 110 and the second target material 112 are joined to the backing plate 130 via the first brazing material 120 and the second brazing material 122, the warp of the sputtering target 100 is generated. It is suppressed.

In the present embodiment, by increasing the area where In is used in each brazing material, it is possible to reduce the warp due to cooling at the time of joining by utilizing the buffering effect peculiar to In.

As shown in FIG. 2, the first target material 110 and the second target material 112 are arranged adjacent to each other so that the backing plate 130 is not sputtered. In the width direction W, the width W _A of the first target material 110 may be shorter than the length W _{B of} the second target material 112 in order to adjust the concentration of each metal component in the sputter film described later. Although not shown, the width W _A of the first target material 110 may be longer than the width W _{B of} the second target material 112.
Further, the ratio S _A / S _B of the area S _B of the main surface of the second target material 112 to the area S _A of the main surface of the first target material 110 may be 1/99 to 99/1. The S _A / S _B is 1/99 or more as the lower limit side, 1/50 or more, may be at 1/20 or more. Also, the S _A / S _B is 99/1 or less as the upper limit side, 50/1 or less, it may be at 20/1 or less.

The backing plate 130 is appropriately selected according to the first and second target materials 110 and 112, and oxygen-free copper, copper alloy, aluminum alloy, titanium, SUS, and molybdenum are used, but other metals ( Materials (including alloys) may also be used.

Further, the thicknesses of the first and second target materials 110 and 112 may be appropriately adjusted because the sputtering rate changes depending on the materials of the target materials 110 and 112.

As shown in FIGS. 3A and 3B, in the sputtering target 200, the first target material 110 is joined onto the backing plate 130 via the first brazing material 120, and the second target material 112 Is joined via the second brazing material 122, and the third target material 214 is joined via the third brazing material 224. At this time, the third target material 214 may be at least one, and when the third target material 214 is divided into a plurality of parts on the backing plate 130, they may be the same material or different materials. ..

The third target material 214 may be formed of the same material as the first target material 110. In such a case, if the second target material 112 is formed of Ag, it is possible to easily make a gradient in the Ag concentration of the In-Ag laminated film. The third brazing material 224 may be made of the same material as the first brazing material 120.

[2. Sputtering target manufacturing method]
FIG. 4 is a flow chart for explaining an embodiment of the method for manufacturing a sputtering target according to the present invention.

In one embodiment, the method for manufacturing a sputtering target according to the present invention includes a first joining step S11, a second joining step S21, and a cooling step S31, as shown in FIG. Hereinafter, preferred embodiments of each step will be described. The duplicated content will be omitted. Further, in the present embodiment, the case where the number of target materials is two is illustrated.

(First joining process)
In the first joining step S11, the second target material 112 is joined onto the backing plate 130 via the molten second brazing material 122.

It is preferable that the temperature of the second brazing material 122 is set to 157 to 250 ° C. and the second brazing material 122 is melted and joined. The upper limit of the temperature is preferably 200 ° C. or lower, more preferably 190 ° C. or lower, and 180 ° C. or lower, from the viewpoint of suppressing the oxidation of the second brazing material 122 itself. Is more preferable. Further, the temperature is 160 ° C. or higher on the lower limit side from the viewpoint that if there is a temperature distribution on the backing plate 130, the second brazing material 122 may solidify and poor adhesion may occur. Is preferable, 165 ° C. or higher is more preferable, and 170 ° C. or higher is even more preferable. After the arrangement of the second target material 112 is completed, the temperature of the backing plate 130 is set to the temperature of the second joining step S21 described later (for example, the temperature of the first brazing material 120 is in the range of 120 to 155 ° C.). The temperature is adjusted to (), and the second joining step S21 proceeds. In the second joining step S21, since the melting point of the second brazing material 122 is higher than the melting point of the first brazing material 120, the first joining step is performed so that the remelting of the first brazing material 120 does not occur. It is preferably carried out after S11.
On the other hand, when the second brazing material 122 is melted at the stage of the joining step S11, the second brazing material 122 is melted at the same time as the joining step S11, and the second target material 112 is placed on the backing plate 130. , May be joined via the melted second brazing material 122.

(Second joining process)
In the second joining step S21, the first target material 110 is joined onto the backing plate 130 via the melted first brazing material 120.

It is preferable that the temperature of the first brazing material 120 is 120 to 155 ° C., and the first brazing material 120 is melted and joined. On the upper limit side, the temperature is preferably 155 ° C. or lower, more preferably 145 ° C. or lower, and 135 ° C. or lower, from the viewpoint of suppressing the oxidation of the first brazing material 120 itself. Is more preferable. Further, the temperature is 120 ° C. or higher on the lower limit side from the viewpoint that if there is a temperature distribution on the backing plate 130, the first brazing material 120 may solidify and poor adhesion may occur. Is more preferable, 125 ° C. or higher is more preferable, and 130 ° C. or higher is even more preferable.

In the second joining step S21, the first target material 110 and the second target material 112 are separated from each other at room temperature after cooling from the viewpoint of preventing the backing plate 130 from being sputtered due to excessive gaps. It may be adjusted so as to be separated by 1 mm or less in the width direction W.

(Cooling process)
After the second joining step S21, the cooling is performed to room temperature in the cooling step S31.

[3. Sputtered film manufacturing method]
In one embodiment, the method for producing a sputtering film according to the present invention includes a film forming step of obtaining a sputtering film by forming a film using the sputtering target described above. There are no particular restrictions on the sputtering equipment that can be used with the sputtering targets 100 and 200. For example, a magnetron sputtering device, an RF application type magnetron DC sputtering device, or the like can be used.

In the method for producing a sputtering film according to the present invention, when the second target material 112 provided in the sputtering targets 100 and 200 described above contains Ag, for example, an In target is used for the first target material 110. By using an Ag target having a narrow width of the second target material 112, it is possible to make a gradient of Ag concentration in the film thickness direction of the sputter film obtained on the substrate passing directly above the target.

In one embodiment of the method for producing a sputtering film according to the present invention, the sputtering targets 100 and 200 are formed by a DC sputtering apparatus based on an example of the following film forming conditions. In this sputtering apparatus, in order to uniformly stack Ag in the film, the substrate passes through the positions facing the sputtering targets 100 and 200.
<Example of film formation conditions>
Power density: 1.0 W / cm ²
Substrate temperature: Room temperature Reached vacuum: 1.0 x 10 ^-3 Pa or less Sputter gas: Ar
Gas flow rate: 100 sccm

[4. How to manufacture solar cells]
In one embodiment, the method for manufacturing a solar cell according to the present invention includes a step of manufacturing a solar cell using the sputter film described above. More specifically, sputtering targets 100 and 200 provided with a first target material 110 formed of In containing 0 to 10000 mass ppm of Cu and a second target material 112 formed of a Cu—Ga alloy. A sputtered film of In-Cu-Ga is formed by sputtering using. Then, the obtained In-Cu-Ga sputtered film is heat-treated in a Se atmosphere to obtain a Cu-In-Ga-Se quaternary alloy film. This Cu-In-Ga-Se quaternary alloy film can be used as a light absorption layer of a CIGS solar cell.

The present invention will be specifically described with reference to Examples and Comparative Examples. The following examples and comparative examples are merely specific examples for facilitating the understanding of the technical contents of the present invention, and the technical scope of the present invention is not limited by these specific examples.

(Example 1)
First, an In target material of 95.0 mm × 508 mm × 5 mmt, an Ag target material of 31.5 mm × 508 mm × 5 mmt, and a copper backing plate 130 of 150 mm × 550 mm × 12 mmt were prepared.

In FIG. 5, when regions A1 to A3 are In target materials (composed integrally), regions A4 are Ag target materials, and B1 to B4 are brazing materials of InSn alloy (In50% by mass, Sn50% by mass). First, the InSn alloy (In50% by mass, Sn50% by mass) brazing material represented by B1 to B4 is placed on the backing plate 130, and heat is applied from the backing plate 130 side to heat the InSn alloy (In50% by mass, Sn50) at 130 ° C. The brazing material (% by mass) was melted. Then, after wetting the bonding surfaces of the In target material and the Ag target material with a brazing material of InSn alloy (In50% by mass, Sn50% by mass), the In target materials A1 to A3 and the Ag target material A4 are arranged so as to be adjacent to each other. Each target material and the backing plate 130 were joined and cooled. As a result, a sputtering target 300 was obtained.

(Average amount of warpage)
The average warp of the backing plate 130 of the sputtering target 300 after joining each target material and the backing plate 130 is subtracted from the average warp of the backing plate 130 before joining each target material and the backing plate 130, and the average. The amount of warpage was calculated.
As shown by the arrow in FIG. 6, the warp measuring method is to obtain the warp on the diagonal line of the back surface of the backing plate 130. The warp was measured by placing a straight edge on the arrow C1 and measuring the distance between the backing plate and the straight edge with a depth gauge. The same operation was performed for the diagonal warp of the backing plate 130 indicated by the other arrow C2. The average of these two warpages was taken as the average warp. The results are shown in Table 1.

(Example 2)
As shown in Table 1, In is arranged on the backing plate 130 as the brazing material B4, the temperature of the backing plate 130 is raised to 170 ° C., the brazing material B4 (In) is melted first, and the target material A4 is arranged. The backing plate 130 was lowered to 135 ° C. to solidify the brazing material B4 (joining step S11). Then, an InSn alloy (Sn50% by mass) is placed as a brazing material in the region of B1 to 3 and melted, the target materials A1 to 3 are placed, the temperature of the backing plate 130 is lowered to 120 ° C. or lower, and the target material A1 to 1 3 and brazing materials B1 to 3 were joined (joining step S21) and cooled. As a result, a sputtering target 300 was obtained. The target materials A1 to A3 were integrally formed.

(Example 3)
The same procedure as in Example 2 was carried out except that the materials of the target materials A3 and A4 were changed to Ag and the brazing materials B3 and B4 were changed to In. The target materials A1 to A2 were integrally formed, and the target materials A3 to A4 were integrally formed.

(Example 4)
In order to produce a target material of an InCu alloy, Cu was added to the dissolved In so as to be 1000% by mass, and the In was formed by containing Cu in In which can be sufficiently recrystallized during plastic working at room temperature. Obtained the target material. Next, a rolling process was performed in which the thickness reduction rate of the target material was 60%. Then, the same procedure as in Example 2 was carried out except that the target materials A1 and A2 were made of In—Cu 1000 mass ppm. The target materials A1 to A2 were integrally formed, and the target materials A3 to A4 were integrally formed.

(Comparative Example 1)
The same procedure as in Example 1 was carried out except that the materials of the target materials A1 to A4 were changed to InAg alloy. The target materials A1 to A4 were integrally formed.

(Discussion by Example)
In Examples 1 to 4, the average warpage was lower than that in Comparative Example 1. It can be said that the sputtering targets 300 obtained in Examples 1 to 4 can be appropriately formed even when used in a sputtering apparatus because they have low warpage.

100, 200, 300 Sputtering target 110 1st target material 112 2nd target material 120 1st brazing material 122 2nd brazing material 130 backing plate 214 3rd target material 224 3rd brazing material A1, A2, A3, A4 Target material B1, B2, B3, B4 Blow material C1, C2 Arrow S11 First joining step S21 Second joining step S31 Cooling step W Width direction W _A First target material width W _B Second Target material width

Claims (14)

Backing plate and
A sputtering target comprising a first target material bonded via a first brazing material and a second target material bonded via a second brazing material on the backing plate.
The first target material is formed of In containing Cu in an amount of 0 to 10000 mass ppm.
The second target material is a sputtering target formed of Ag. The sputtering target according to claim 1, wherein the melting point of the first brazing material is 150 ° C. or lower. The sputtering target according to claim 1 or 2, wherein the first brazing material is formed of at least one selected from the group consisting of InSn alloy, InBi alloy, and InZn alloy. The sputtering target according to claim 3, wherein the InSn alloy contains 10 to 60% by mass of Sn, and the balance is In and unavoidable impurities. The sputtering target according to any one of claims 1 to 4, wherein the second brazing material is formed of an In or InSn alloy. The sputtering target according to any one of claims 1 to 5, further comprising at least one third target material bonded onto the backing plate via a third brazing material. The sputtering target according to claim 6, wherein the third target material is made of the same material as the first target material. The area of the first area of the major surface of the target material (S _A) relative to the main surface of the second target material ratio of _{(S B) (S A /} S B) is 1 / 99-99 / 1, The sputtering target according to any one of claims 1 to 7. The method for manufacturing a sputtering target according to any one of claims 1 to 8.
A first joining step of joining the second target material onto the backing plate via a molten second brazing material,
The backing plate includes a second joining step of joining the first target material via a melted first brazing material.
The first target material is formed of In containing Cu in an amount of 0 to 10000 mass ppm.
A method for producing a sputtering target, wherein the second target material is made of Ag. In the first joining step, the temperature of the second brazing material for joining the second target material on the backing plate via the second brazing material is set in the range of 157 to 250 ° C. The method for manufacturing a sputtering target according to claim 9. In the second joining step, the temperature of the first brazing material for joining the first target material on the backing plate via the first brazing material is set in the range of 120 to 155 ° C. The method for manufacturing a sputtering target according to claim 9 or 10. The method for manufacturing a sputtering target according to any one of claims 9 to 11, wherein the second joining step is carried out after the first joining step. A method for producing a sputtered film, which comprises a step of obtaining a sputtered film by a sputtering method using the sputtering target according to any one of claims 1 to 8. A method for manufacturing a solar cell, which comprises a step of manufacturing a solar cell using the sputter film obtained by the method for manufacturing a sputter film according to claim 13.