Sputtering target and method for producing the same

Abstract

A sputtering target is a sputtering target composed of a plurality of constituent members including a target material and a substrate, wherein the plurality of constituent members include a first constituent member and a second constituent member stacked on each other, wherein the first constituent member contains Al, and the second constituent member contains Cu, and at least one of the first constituent member and the second constituent member contains Mg, and the sputtering target has an alloy layer between the first constituent member and the second constituent member, wherein the alloy layer contains Al and Cu and is in contact with the first constituent member and the second constituent member, and the alloy layer also includes a Mg-containing layer containing 5.0 at% or more of Mg in at least a portion of the alloy layer.

Description

Technical Field

[0001] This specification discloses a technology related to a sputtering target and a method for producing the sputtering target. Background Art

[0002] In recent years, along with the rapid progress of semiconductor-related technologies, there is a trend toward high integration of semiconductors and miniaturization of electronic devices equipped with semiconductor chips. Under such circumstances, in the manufacture of electronic devices, many thin films are formed by sputtering using various sputtering targets. The thin films include, for example, titanium or titanium alloy films, titanium silicide films, or titanium nitride films, and in sputtering, a sputtering target having a target material made of a material such as titanium corresponding to the material of the thin film is used.

[0003] The formation of a thin film by sputtering is performed, for example, in the following manner. First, in a vacuum, an inert gas such as Ar gas is introduced while a high voltage is applied between the substrate and the sputtering target. Then, the ionized Ar gas is + Ions such as the above collide with the target material of the sputtering target. The impact energy is used to release atoms in the target material and deposit them on the substrate. Thus, a thin film is formed on the substrate. It should be noted that, as for the sputtering target, there are flat sputtering targets or cylindrical sputtering targets, etc., which are usually sputtering targets having a target material and a substrate overlapping and bonded with the target material.

[0004] Among such technologies, as technologies related to a target material mainly containing titanium, there are technologies described in Patent Documents 1 to 5, for example.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: International Publication No. 01 / 38598

[0008] Patent Document 2: U.S. Patent No. 6755948

[0009] Patent Document 3: Japanese Patent Application No. 2001-509548

[0010] Patent Document 4: U.S. Patent No. 5,993,621

[0011] Patent Document 5: Japanese Patent Application Publication No. 2010-235998 Summary of the invention

[0012] Problems to be solved by the invention

[0013] However, in a sputtering target composed of a plurality of components including a target material and a substrate, it is sometimes impossible to sufficiently firmly bond the first component and the second component stacked on each other. In this case, due to the thermal expansion during sputtering and the warpage caused by the contraction during cooling, peeling occurs at the bonding interface, which may affect the sputtering process.

[0014] This specification discloses a sputtering target and a method for producing the sputtering target, which are capable of firmly bonding a first component member and a second component member stacked on each other in the sputtering target.

[0015] Solutions for solving problems

[0016] The sputtering target disclosed in the present specification is a sputtering target composed of a plurality of constituent members including a target material and a substrate, the plurality of constituent members including a first constituent member and a second constituent member stacked on each other, the first constituent member containing Al, and the second constituent member containing Cu, at least one of the first constituent member and the second constituent member containing Mg, the sputtering target having an alloy layer between the first constituent member and the second constituent member, the alloy layer containing Al and Cu and being in contact with the first constituent member and the second constituent member, the alloy layer including a Mg-containing layer containing 5.0 at% or more of Mg in at least a portion of the alloy layer.

[0017] In addition, the manufacturing method of the sputtering target disclosed in the present specification is a method for manufacturing a sputtering target composed of a plurality of constituent members including a target material and a substrate, the plurality of constituent members including a first constituent member and a second constituent member stacked on each other, the first constituent member containing Al, and the second constituent member containing Cu, at least one of the first constituent member and the second constituent member containing Mg, the manufacturing method of the sputtering target including: a preparation step of preparing the plurality of constituent members including the first constituent member and the second constituent member; and a joining step of joining by applying pressure while the plurality of constituent members including the first constituent member and the second constituent member are stacked.

[0018] Effects of the Invention

[0019] According to the above-described sputtering target and method for producing the sputtering target, the first constituent member and the second constituent member stacked on each other in the sputtering target can be firmly joined. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a plan view of a sputtering target showing a position at which a sample is taken when measuring the bonding strength between an embedding material and a substrate.

[0021] Figure 2 This is a SEM image of a cross section of the sputtering target of Example 1 in the thickness direction.

[0022] Figure 3 This is a SEM image of a cross section of the sputtering target of Example 2 in the thickness direction.

[0023] Figure 4 This is a SEM image of a cross section of the sputtering target of Comparative Example 1 in the thickness direction.

[0024] Figure 5 This is a SEM image of a cross section of the sputtering target of Comparative Example 2 in the thickness direction.

[0025] Figure 6 This is a SEM image showing a scanning range obtained by line scanning (Line Scan) of EDX for a cross section in the thickness direction of the sputtering target of Example 1, and a graph showing changes in the content of each element.

[0026] Figure 7 This is a SEM image showing a scanning range obtained by line scanning of EDX for a cross section in the thickness direction of the sputtering target of Example 2, and a graph showing changes in the content of each element.

[0027] Figure 8 This is a SEM image showing a scanning range obtained by line scanning of EDX for a cross section in the thickness direction of the sputtering target of Example 3, and a graph showing changes in the content of each element.

[0028] Fig. 9 This is a SEM image showing a scanning range obtained by line scanning of EDX for a cross section in the thickness direction of the sputtering target of Comparative Example 1, and a graph showing changes in the content of each element.

[0029] Fig.10 This is a SEM image showing a scanning range obtained by line scanning of EDX for a cross section in the thickness direction of the sputtering target of Comparative Example 2, and a graph showing changes in the content of each element. DETAILED DESCRIPTION

[0030] Hereinafter, embodiments of the sputtering target and the method for producing the sputtering target will be described in detail.

[0031] A sputtering target of one embodiment is composed of a plurality of constituent members including a target material and a substrate. The plurality of constituent members include a first constituent member and a second constituent member stacked on each other, the first constituent member containing Al, the second constituent member containing Cu, and at least one of the first constituent member and the second constituent member containing Mg. The sputtering target has an alloy layer between the first constituent member and the second constituent member, the alloy layer containing Al and Cu, and being connected to the first constituent member and the second constituent member. The alloy layer includes a Mg-containing layer containing Mg of 5.0 at% or more in at least a portion of the alloy layer. It should be noted that, hereinafter, for the sake of convenience of explanation, one constituent member containing Al among the constituent members of the sputtering target stacked on each other is referred to as the first constituent member, and the other constituent member containing Cu is referred to as the second constituent member.

[0032] In a sputtering target in which a target material and a substrate are stacked, sometimes one of the target material or the substrate is a first constituent member containing Al, and the other is a second constituent member containing Cu. In addition, in a sputtering target in which a target material, an embedding material, and a substrate are stacked in sequence, sometimes the target material is a first constituent member containing Al, and the embedding material is a second constituent member containing Cu, and sometimes the embedding material is a first constituent member containing Al, and the substrate is a second constituent member containing Cu.

[0033] It is known that for such a first component containing Al and a second component containing Cu, even if you want to keep them as they are and directly stack them to join, the joining strength will also decrease. It is believed that the reason is that at the interface between the first component and the second component, Cu and Al form fragile intermetallic compounds (CuAl, CuAl2, etc.) by mutual diffusion. When the joining strength between the first component and the second component is low, the first component and the second component may peel off at the joining interface due to thermal expansion and contraction during cooling during sputtering.

[0034] In contrast, in the present embodiment, there is an alloy layer between the first constituent member and the second constituent member, the alloy layer contains Al and Cu, and is in contact with the first constituent member and the second constituent member, and the alloy layer includes a Mg-containing layer containing 5.0at% or more of Mg in addition to Al and Cu in at least a portion thereof. As a result, the first constituent member and the second constituent member are firmly joined. It is speculated that the reason is that in the Mg-containing layer in at least a portion of such an alloy layer, Mg is also contained together with Cu and Al, thereby suppressing the formation of intermetallic compounds of Cu and Al, and forming a more solid alloy of Al, Cu, and Mg. However, it is not limited to the above theory, and it is sufficient that at least a portion of the alloy layer containing Al and Cu between the first constituent member and the second constituent member contains a Mg-containing layer, and the Mg-containing layer contains Al, Cu, and Mg and has a portion with a Mg content of 5.0at% or more.

[0035] Here, the following examples are mainly described: in a sputtering target in which a target material, an embedding material, and a substrate are sequentially stacked, an example in which the first constituent member is set as an embedding material and the second constituent member is set as a substrate, or an example in which the first constituent member is set as a substrate and the second constituent member is set as an embedding material. In addition, the detailed description is omitted, and either the first constituent member or the second constituent member may be set as a target material and the other may be set as an embedding material. Furthermore, a sputtering target that does not contain an embedding material may also be used as an object. For example, the first constituent member may be set as a target material and the second constituent member may be set as a substrate, or the first constituent member may be used as a substrate and the second constituent member may be set as a target material.

[0036] (Target)

[0037] The target has a sputtering surface for sputtering, and is usually a target in the shape of a disk or other flat plate, or a cylinder.

[0038] The material of the target can be appropriately determined according to the material of the thin film formed on the substrate by sputtering. If the embedded material contains Al, the target can be made of a material that can be bonded to the embedded material containing Al, such as Ti, Ta, Cu, Cu alloy, W, WSi, Co, Al, etc.

[0039] Typically, the target contains Ti. In this case, the target can be made of pure Ti mainly containing Ti. The Ti content of the pure Ti target is typically 99.995% by mass or more, sometimes 99.999% by mass or more, and further 99.9995% by mass or more. The pure Ti target sometimes contains at least one impurity selected from the group consisting of Al, Fe, Ni and Cu.

[0040] Alternatively, the target material may be made of a Ti alloy containing Ti and Al. In the case of the target material made of the Ti alloy, the Al content is, for example, 30 at % to 70 at %, and as an example, may be about 50 at %.

[0041] (Base material)

[0042] The substrate has a flat plate or cylindrical shape corresponding to the target material, and is arranged on the back side opposite to the sputtering surface of the target material, and is sometimes also called a back plate or back tube. In this embodiment, the substrate is arranged in a manner of sandwiching an embedded material described later between the substrate and the target material. That is, the sputtering target of this embodiment is formed by stacking the target material, the embedded material, and the substrate in this order.

[0043] When the embedded material described later is a first constituent member containing Al, the substrate is set as a second constituent member containing Cu. Alternatively, when the embedded material is a second constituent member containing Cu, the substrate is set as a first constituent member containing Al. Typically, the embedded material is a first constituent member containing Al, and the substrate is a second constituent member containing Cu.

[0044] More specifically, when the substrate is the second constituent member, it may be made of pure Cu mainly containing Cu. Alternatively, when the substrate is the first constituent member, it may be made of pure Al mainly containing Al.

[0045] Alternatively, when the substrate is the second component, it may be made of a Cu alloy containing Cu and Mg. Alternatively, when the substrate is the first component, it may be made of an Al alloy containing Al and Mg. In addition to Mg, Al alloys sometimes contain Si, Mn, Cr, Zn, etc. In a specific embodiment, the substrate does not contain Mg, and the embedded material further contains Mg. However, both the substrate and the embedded material may contain Mg.

[0046] It is particularly preferred that the substrate is composed of a Cu alloy or an Al alloy containing Mg. In this case, the Mg content in the substrate is preferably 1.0 mass % to 10.0 mass %, and more preferably 3.4 mass % or more. When the Mg content in the substrate is too low, there is a concern that it is difficult to form an alloy layer including a Mg-containing layer containing Al, Cu and Mg between the substrate and the embedded material, and the required bonding strength between the substrate and the embedded material cannot be ensured. When the Mg content in the substrate is too high, the original properties required for the substrate containing Mg may be impaired.

[0047] (Embedded material)

[0048] Sometimes an embedded material is sandwiched between the target and the substrate. The embedded material is sometimes provided for the purpose of improving the bonding strength between the target and the substrate and for the purpose of metal diffusion bonding. In addition, the embedded material has functions such as alleviating the warping of the sputtering target and absorbing strain during sputtering.

[0049] As described above, when the substrate is the second constituent member and contains Cu, the embedding material is the first constituent member and contains Al, or when the substrate is the first constituent member and contains Al, the embedding material is the second constituent member and contains Cu.

[0050] More specifically, when the insert material is the first constituent member, it may be made of pure Al mainly containing Al. Alternatively, when the insert material is the second constituent member, it may be made of pure Cu mainly containing Cu.

[0051] Alternatively, when the embedded material is the first component, it may be made of an Al alloy containing Al and Mg. In addition to Mg, the Al alloy sometimes also contains Si, Mn, Cr, Zn, etc. Alternatively, when the embedded material is the second component, it may be made of a Cu alloy containing Cu and Mg.

[0052] It is particularly preferred that the embedded material is composed of an Al alloy or a Cu alloy containing Mg. In this case, the Mg content in the embedded material is preferably 1.0 mass % to 10.0 mass %, and more preferably 3.4 mass % or more. When the Mg content in the embedded material is too little, there is a concern that it is difficult to form an alloy layer including a Mg-containing layer containing Al, Cu and Mg between the substrate and the embedded material, and the required bonding strength between the substrate and the embedded material cannot be ensured. When the Mg content in the embedded material is too much, the original required properties of the embedded material containing Mg may be impaired.

[0053] (Alloy layer)

[0054] Between a first constituent member such as an embedding material and a second constituent member such as a substrate, there is an alloy layer containing at least Al and Cu, and at least a portion of the alloy layer includes a Mg-containing layer containing three elements, namely Al, Cu and Mg. The Mg-containing layer contains Mg of more than 5.0at%. The first constituent member and the second constituent member are firmly bonded through the Mg-containing layer. In addition to the Mg-containing layer, the alloy layer sometimes also includes a layer that does not contain Mg and contains Al and Cu. Even if there is a layer that does not contain Mg in the alloy layer, as long as there is a Mg-containing layer, a strong alloy of these three elements will be formed, which can improve the bonding strength between the first constituent member and the second constituent member. However, in the case where there is a portion containing both Al and Cu, an intermetallic compound of Al and Cu may be formed in this portion. Therefore, it is preferred to form a Mg-containing layer in a wider range in the alloy layer.

[0055] By performing SEM-EDX (energy dispersive X-ray analysis) on a cross section in the thickness direction perpendicular to the sputtering surface of the target material of the sputtering target, the alloy layer and the Mg-containing layer can be confirmed and the contents of the three elements can be measured.

[0056] The alloy layer refers to a portion between the first constituent member and the second constituent member where the respective contents of Al and Cu are both 5.0 at% or more in terms of the element ratio on the line when performing a line scan of SEM-EDX along the thickness direction of a cross section along the thickness direction of the sputtering target. The alloy layer is between the position on the first constituent member side where both Al and Cu are 5.0 at% or more and the position on the second constituent member side where both Al and Cu are 5.0 at% or more. When confirming the content of Al or Cu from the alloy layer toward the first constituent member or the second constituent member near the boundary between the alloy layer and the first constituent member or the second constituent member, if the content of Al or Cu does not decrease to less than 5.0 at%, the position where the content converges to a certain value is taken as the boundary position between the alloy layer and the first constituent member or the second constituent member.

[0057] The Mg-containing layer is a portion containing the three elements of Al, Cu and Mg in the above-mentioned alloy layer, and the Mg content is 5.0at% or more. The presence or absence of the Mg-containing layer can be confirmed by performing a line scan of SEM-EDX along the thickness direction of the cross-section along the thickness direction of the sputtering target. Even if there is a portion containing the three elements of Al, Cu and Mg in the alloy layer, if the Mg content in any part of the portion is less than 5.0at%, the portion is not considered to be a Mg-containing layer. The conditions for the line scan of SEM-EDX are set to a magnification of 1000 to 2000 times, a distance between the objective lens and the sample (WD, Working distance): 10 mm, and a scanning distance of 30μm to 50μm.

[0058] The thickness of the alloy layer is preferably 5μm to 20μm, and more preferably 10μm to 15μm. If the thickness of the alloy layer is too thin, there is a concern that the effect of improving the bonding strength brought by the Mg-containing layer cannot be fully obtained, and the bonding strength is reduced. On the other hand, if the thickness of the alloy layer is too thick, the bonding strength based on the intermetallic compound layer of Cu and Al is dominant, and the bonding strength may be reduced. The above-mentioned thickness of the alloy layer refers to the distance in the thickness direction between the position where the content of both Al and Cu is 5.0at% or more on the first component side and the position where the content of both Al and Cu is 5.0at% or more on the second component side when a SEM-EDX line scan is performed on a section passing through the radial center of the sputtering target and along the thickness direction.

[0059] When performing line scanning of SEM-EDX along the thickness direction of the sputtering target, the thickness of the Mg-containing layer is preferably 20% or more of the thickness of the alloy layer. This can significantly increase the bonding strength.

[0060] The Mg-containing layer is preferably formed over a large area between the first constituent member and the second constituent member. When observing a cross section along the thickness direction through the center of the top view of the sputtering target (when the sputtering target is a disk-shaped target, the top view of the sputtering target observed from the sputtering surface side is circular, so it is the radial center of the circle), the Mg-containing layer is preferably formed in a direction orthogonal to the thickness direction of the cross section, with a proportion of more than 50% of the overall width of the first constituent member and the second constituent member. The width of the first constituent member and the second constituent member referred to here refers to the length of the area where these first constituent members overlap with the second constituent member in the cross section along the above-mentioned thickness direction, along the direction orthogonal to the thickness direction. When the Mg-containing layer exists in such a large proportion in the direction orthogonal to the thickness direction, the bonding strength can be further improved. In a part of the area where the first constituent member and the second constituent member overlap, there may be a part where the Mg-containing layer does not exist.

[0061] The alloy layer and the Mg-containing layer are preferably formed by diffusion bonding of the first constituent member and the second constituent member. In this case, in the alloy layer, the Al content of the portion in contact with the second constituent member is sometimes less than that of the portion in contact with the first constituent member. In addition, in the alloy layer, in terms of Cu content, the Cu content of the portion in contact with the first constituent member is sometimes less than that of the portion in contact with the second constituent member.

[0062] (Joint strength)

[0063] The bonding strength between the embedding material (first component) and the base material (second component) is preferably 5 kgf / mm 2 More preferably, 10 kgf / mm 2 If the bonding strength between the embedded material and the substrate is too low, there is a concern that the bonding interface through the alloy layer may be peeled off due to thermal expansion during sputtering and contraction during cooling. It should be noted that excessive bonding strength will not cause any particular problems, but sometimes 15kgf / mm 2 the following.

[0064] The bonding strength between the embedding material and the substrate is measured as follows. First, a sample including the target material, the embedding material and the substrate in the thickness direction is selected from a sputtering target having a target material, an embedding material and a substrate. Figure 1 In the circular sputtering target 1 shown in top view, a total of seven locations are used as sample selection locations Ps, including one location in the center when viewed from above, three locations equally spaced apart in the circumferential direction on the outer peripheral side, and three locations in the center in the radial direction between these central points and the outer peripheral points.

[0065] Afterwards, each of these samples was subjected to a uniaxial tensile test along the thickness direction using a tensile tester. Then, the strength of the sample corresponding to the embedded material and the base material was measured when peeled off. The average value of the strength in each sample was taken as the bonding strength.

[0066] (Manufacturing method)

[0067] The above-mentioned sputtering target can be produced, for example, as follows.

[0068] First, as a preparation step, a plurality of constituent members including a first constituent member and a second constituent member are prepared. The first constituent member contains Al, the second constituent member contains Cu, and at least one of the first constituent member and the second constituent member is made of an alloy containing Mg.

[0069] When manufacturing a sputtering target in which a target material, an embedding material, and a substrate are sequentially stacked, the target material, embedding material, and substrate are prepared separately. In this embodiment, either the embedding material or the substrate is used as the first constituent member, and the other is used as the second constituent member.

[0070] As mentioned above, typically, the embedded material is a first constituent member containing Al, and the substrate is a second constituent member containing Cu. In addition, typically, the substrate does not contain Mg, and the embedded material further contains Mg. In a specific embodiment, the embedded material is an Al alloy containing Mg. It should be noted that the target material can be, for example, a target material containing Ti.

[0071] After that, a joining process is performed, and a plurality of constituent members including a first constituent member and a second constituent member are stacked and pressurized and joined. In this embodiment, the target material, the embedded material and the substrate are stacked in sequence, and in this stacked state, they are pressurized and joined in the thickness direction. At this time, the Mg diffuses from the first constituent member and / or the second constituent member containing Mg as described above to the interface between the first constituent member and the second constituent member, and the Al and Cu contained in the first constituent member and the second constituent member also diffuse at the interface. As a result, an alloy layer containing at least Al and Cu is formed at the interface between the embedded material and the substrate, and a Mg-containing layer containing Mg of more than 5.0at% is also formed in the alloy layer. The Mg-containing layer containing the three elements of Al, Cu and Mg in the alloy layer is high in strength, so the above-mentioned Mg-containing layer is formed at the interface between the first constituent member and the second constituent member, thereby firmly joining the first constituent member and the second constituent member. Here, the embedded material as either the first constituent member or the second constituent member is firmly joined to the substrate as the other.

[0072] The bonding process can be carried out by hot isostatic pressing (HIP), hot pressing or cold isostatic pressing (CIP) and other various methods. Among them, hot isostatic pressing is to apply static pressure (hydrostatic pressure) while heating at a relatively high temperature, so it is easy to make the entire interface diffuse and bond effectively. From this aspect, hot isostatic pressing is preferred.

[0073] After the bonding step, a sputtering target having a target material, an embedding material and a substrate stacked in sequence is obtained. The sputtering target forms an alloy layer including at least a portion of a Mg-containing layer containing Al, Cu and Mg between the embedding material and the substrate, so that the embedding material and the substrate can be bonded with a desired strength.

[0074] [Example]

[0075] Next, the above-mentioned sputtering target was trial-produced and its effect was confirmed, so it is described below. However, the description here is only for illustration and is not intended to be limiting.

[0076] Pure Ti target material, embedded material and substrate were prepared respectively.

[0077] In Example 1, as a substrate, a Cu-Ni-Si alloy substrate containing 1.8 to 3.0 mass % Ni, 0.4 to 0.8 mass % Si, and the remainder containing Cu was prepared, and as an embedding material, an embedding material made of a Mg-based Al alloy containing about 4.0 to 4.9 mass % Mg, about 0.05 to 0.25 mass % Cr, about 0.4 to 1.0 mass % Mn, and the remainder containing Al was prepared. Then, the target material, the embedding material, and the substrate were stacked in sequence and hot isostatic pressing (HIP) was performed. Thus, a sputtering target was manufactured.

[0078] In Example 2, a sputtering target was produced in the same manner as in Example 1 except that an insert material made of a Mg-based Al alloy containing about 2.2 to 2.8 mass % of Mg, 0.15 to 0.35 mass % of Cr, and the balance of Al was used as the insert material.

[0079] In Example 3, a sputtering target was produced in the same manner as in Example 1 except that the temperature and time of HIP were increased.

[0080] In Comparative Example 1, a sputtering target was produced in the same manner as in Example 1, except that a pure Al-made insert material mainly composed of Al was used as the insert material.

[0081] In Comparative Example 2, a sputtering target was manufactured in the same manner as in Example 1, except that an embedding material made of a Cu-based Al alloy containing about 3.5 to 4.5 mass % Cu, about 0.4 to 0.8 mass % Mg, about 0.2 to 0.8 mass % Si, 0.4 to 0.8 mass % Mn, and the remainder containing Al was used as the embedding material.

[0082] The cross-sections in the thickness direction of each sputtering target of Examples 1 and 2 and Comparative Examples 1 and 2 were observed using SEM-EDX. The images are shown in FIG. Figures 2 to 5 .according to Figure 2 and 3 It is believed that an alloy layer containing Al and Cu is formed at the interface between the target and the substrate.

[0083] In addition, a line scan using EDX was performed on the cross section in the thickness direction of each sputtering target of Examples 1 to 3 and Comparative Examples 1 and 2. The line scan was performed on a sample selected from a position 1 / 2R (a position half the radius R, a center position of the radius) of the cross section passing through the radial center of the sputtering target and along the thickness direction. The results are shown in Figures 6 to 10 . Figures 6 to 10 In the graph of , the horizontal axis is the measured amount and the vertical axis is the element ratio (at %).

[0084] according to Figures 6 to 8 It is found that in the sputtering targets of Examples 1 to 3, there is a Mg-containing layer in the alloy layer containing Al, Cu, and Mg, and at least a part of the Mg content is 5.0 at % or more. Figure 6 In the embodiment 1 shown, the thickness of the alloy layer is about 10 μm, and the thickness of the Mg-containing layer is about 4 μm. Figure 7 In the embodiment 2 shown, the thickness of the alloy layer is about 7.63 μm, and the thickness of the Mg-containing layer is about 1.55 μm. In the embodiment 3, the thickness of the alloy layer is about 15 μm, and the thickness of the Mg-containing layer is about 7 μm. In any of the embodiments 1 to 3, the thickness of the Mg-containing layer is more than 20% of the thickness of the alloy layer. It should be noted that in the embodiment 2 ( Figure 7 ), on the substrate side, the Al content in the alloy layer does not decrease to less than 5.0 at %, but the Al content converges to a certain value (about 10 at %), and it is believed that the position where the convergence begins is the boundary between the alloy layer and the substrate.

[0085] In contrast, in the sputtering targets of Comparative Examples 1 and 2, Fig. 9 and 10 As shown, even if the alloy layer contains Mg, the Mg content is less than 5.0 at %, and it can be said that the Mg-containing layer does not exist.

[0086] In addition, the bonding strength of each of the sputtering targets of Examples 1 to 3 and Comparative Examples 1 and 2 was measured using a tensile tester (Autograph AG-100kNX plus manufactured by Shimadzu Corporation) according to the above-mentioned method.

[0087] [Table 1]

[0088]

[0089] The test results of the bonding strength shown in Table 1 show that the sputtering targets of Examples 1 to 3 exhibit high bonding strength between the embedding material and the substrate. On the other hand, the sputtering targets of Comparative Examples 1 and 2 have lower bonding strength than the sputtering targets of Examples 1 to 3.

[0090] Furthermore, when Examples 1 to 3 are compared, it can be seen that the bonding strength is increased by increasing the Mg content of the embedded material.

[0091] As described above, by forming a Mg-containing layer containing Al, Cu and Mg and containing 5.0 at % or more of Mg in at least a portion of the alloy layer between the first constituent member such as the insert material and the substrate, the first constituent member and the second constituent member can be firmly joined.

[0092] Description of Reference Numerals

[0093] 1: sputtering target; Ps: sample selection site.

Claims

1. A sputtering target, comprising a plurality of components including a target material and a substrate, The plurality of constituent members include a first constituent member and a second constituent member stacked on each other, The first constituent member contains Al, and the second constituent member contains Cu, At least one of the first constituent member and the second constituent member contains Mg, The sputtering target has an alloy layer between the first constituent member and the second constituent member, the alloy layer contains Al and Cu and is in contact with the first constituent member and the second constituent member. The alloy layer includes a Mg-containing layer further containing 5.0 at % or more of Mg in at least a portion of the alloy layer.

2. The sputtering target according to claim 1, wherein The sputtering target further includes an embedding material, and the target material, the embedding material, and the substrate are stacked in this order. The first constituent member is one of the embedding material and the base material, and the second constituent member is the other of the embedding material and the base material.

3. The sputtering target according to claim 2, wherein: The first constituent member is the embedding material, and the second constituent member is the base material.

4. The sputtering target according to any one of claims 1 to 3, wherein The bonding strength between the first component and the second component is 5 kgf / mm 2 above.

5. The sputtering target according to any one of claims 1 to 3, wherein The target material contains Ti.

6. The sputtering target according to any one of claims 1 to 3, wherein The alloy layer and the Mg-containing layer are formed by diffusion bonding of the first constituent member and the second constituent member.

7. The sputtering target according to any one of claims 1 to 3, wherein In the alloy layer, the Al content is lower in a portion in contact with the second constituent member than in a portion in contact with the first constituent member.

8. The sputtering target according to any one of claims 1 to 3, wherein In the alloy layer, the Cu content is lower in a portion in contact with the first constituent member than in a portion in contact with the second constituent member.

9. The sputtering target according to any one of claims 1 to 3, wherein When line scanning of SEM-EDX is performed along the thickness direction of the sputtering target, the thickness of the Mg-containing layer is 20% or more of the thickness of the alloy layer.

10. The sputtering target according to any one of claims 1 to 3, wherein When observing a cross section along the thickness direction passing through the center of the sputtering target in a plan view, the Mg-containing layer is formed at a ratio of 50% or more of the total width of the first constituent member and the second constituent member in a direction orthogonal to the thickness direction.

11. A method for producing a sputtering target, the method comprising producing the sputtering target according to any one of claims 1 to 10, The manufacturing method comprises: a preparation step of preparing the plurality of constituent members including the first constituent member and the second constituent member; as well as The joining step is to pressurize and join a plurality of constituent members including the first constituent member and the second constituent member in a stacked state.

12. The method for producing a sputtering target according to claim 11, wherein: The sputtering target further includes an embedding material, and the target material, the embedding material, and the substrate are stacked in this order. In the preparation step, a target material, an embedding material, and a substrate are prepared, the first constituent member is one of the embedding material and the substrate, and the second constituent member is the other of the embedding material and the substrate.

13. A method for producing a sputtering target, the method comprising producing a sputtering target composed of a plurality of constituent members including a target material and a substrate, The plurality of constituent members include a first constituent member and a second constituent member stacked on each other, The first constituent member contains Al, and the second constituent member contains Cu, At least one of the first constituent member and the second constituent member contains Mg, The manufacturing method comprises: a preparation step of preparing the plurality of constituent members including the first constituent member and the second constituent member; as well as a bonding step of bonding a plurality of constituent members including the first constituent member and the second constituent member by applying pressure while the plurality of constituent members are stacked, The sputtering target further includes an embedding material, and the target material, the embedding material, and the substrate are stacked in this order. In the preparation step, a target material, an embedding material, and a substrate are prepared, the first constituent member is one of the embedding material and the substrate, and the second constituent member is the other of the embedding material and the substrate. The Mg content in the substrate or the intercalation material is 1.0 mass % to 10.0 mass %.

14. The method for producing a sputtering target according to claim 11 or 13, wherein: The bonding step is performed by hot isostatic pressing.

15. The method for producing a sputtering target according to claim 12 or 13, wherein: The first constituent member prepared in the preparing step is the embedding material, and the second constituent member is the base material.

16. The method for producing a sputtering target according to claim 11 or 13, wherein: The target material contains Ti.

17. The method for producing a sputtering target according to claim 11 or 13, wherein: In the bonding step, the first constituent member and the second constituent member are bonded by diffusion bonding.

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