High-entropy alloy, film-forming device, and method for producing high-entropy alloy film
Patent Information
- Application Number
- PCT/JP2026/005114
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-04-17
- Filing Date
- 2026-02-13
- Publication Date
- 2026-10-22
Smart Images
Figure JP2026005114_22102026_PF_FP_ABST
Abstract
Description
High-entropy alloy, film deposition apparatus, and method for manufacturing a high-entropy alloy film.
[0001] This invention relates to a high-entropy alloy, a film deposition apparatus, and a method for producing a high-entropy alloy film.
[0002] One of the innovative technologies in materials science is high-entropy alloys. Unlike binary or ternary alloy materials consisting of a main component and minor components, high-entropy alloys are generally described as multi-component alloys in which five or more metallic elements are dissolved in high concentrations. Such a special composition results in complex physicochemical properties and is expected to exhibit new functions and performance that could not be achieved with existing materials. For example, if a low thermal conductivity alloy exhibiting extremely low thermal conductivity can be realized with a high-entropy alloy, it could be applied to insulation materials for window glass, greatly improving the quality of life in human society. Furthermore, high-entropy alloys are known to exhibit excellent mechanical properties such as a large elastic limit due to lattice strain (Non-Patent Literature 1), and thus applications in fields such as aerospace and nuclear power are also expected.
[0003] FeCoNiCrMn alloy is known as a high-entropy alloy exhibiting low thermal conductivity, and its thermal conductivity has been reported to be 5.6 W / (m·K) at 50K (Non-Patent Document 1).
[0004] Al ｘ CoCrFeNi alloys are also known as high-entropy alloys with low thermal conductivity (Non-Patent Literature 2). Non-Patent Literature 2 describes Al alloys in which the Al composition ratio x is varied in the range of 0.0 at.% to 2.0 at.%. ｘ The CoCrFeNi alloy is being manufactured by arc melting. ｘ It has been shown that the thermal conductivity of CoCrFeNi alloy is approximately 10.5 W / (m·K) to 20.3 W / (m·K) at 289 K.
[0005] On the other hand, Non-Patent Document 3 describes Al with an Al composition ratio x of 0.3. ０．３ CoCrFeNi was fabricated in a vacuum induction melting furnace, and its thermal conductivity was reported to be 5.989 W / (m·K) at 300 K.
[0006] Theoretical prediction of high-entropy alloys exhibiting low thermal conductivity has also been actively conducted. For example, Non-Patent Document 4 predicts lattice thermal conductivity and electronic thermal conductivity by machine learning, and identifies Al as a material with these low thermal conductivities ８ Cr ３０ Co １９ Ni ２０ Fe ２３ as a candidate.
[0007] As far as the applicant is aware, the alloy with the lowest thermal conductivity among the alloys known to date is Lumiloy (registered trademark) LZR55 manufactured by Ishihara Sangyo Co., Ltd. (Non-Patent Document 5). Lumiloy (registered trademark) LZR55 is not a high-entropy alloy but an amorphous alloy containing less than five metal elements. Its published thermal conductivity value is 5.4 W / (m·K), and a high-entropy alloy may be able to achieve an even lower thermal conductivity than this value.
[0008] When searching for high-entropy alloys exhibiting such functions, the optimization of the ratio of the mixed elements and the structure becomes a challenge. By varying these factors, various physical property values can be adjusted, but since there are countless combinations of these factors and an enormous number of experiments are required, the search for new materials is not easy.
[0009] Note that Non-Patent Document 6 discloses a material having even lower thermal conductivity than Lumiloy (registered trademark) LZR55, which is (Dy ０．２ Ho ０．２ Er ０．２ Y ０．２ Yb ０．２ ) ３ NbO ７ ceramics. Although this ceramic has an extremely low thermal conductivity of 0.724 W / (m·K) at room temperature, it requires firing at 1650°C for 5 hours for crystallization, and cannot be produced easily and at low cost. Moreover, in this ceramic, all six elements other than oxygen, namely Dy (dysprosium), Ho (holmium), Er (erbium), Y (yttrium), Yb (ytterbium), and Nd (neodymium), are rare rare earth elements, which makes it extremely expensive.
[0010] Furthermore, Non-Patent Document 7 describes a high-entropy (Mg, Co, Ni, Zn)Ti with a quasi-titanium plate structure having a thermal conductivity of 1.84 W / (m·K) at room temperature. ２ O ５ A ceramic material is disclosed. Although this ceramic material also has a lower thermal conductivity than Lumilloy® LZR55, it still requires firing at 1100°C to 1400°C for crystallization, making it impossible to manufacture easily and at low cost.
[0011] Therefore, in order to enable simple and low-cost manufacturing, it is preferable to achieve low thermal conductivity with an amorphous high-entropy alloy that does not require firing for crystallization.
[0012] H. Wang, et al., “Exceptionally low thermal conductivity in distorted high entropy alloy,” Materials Research Letters, Vol. 13, pp. 24-34, 2025, Taylor & Francis H. P. Chou, et al., “Microstructure, thermophysical and electrical properties in AlxCoCrFeNi (0 ≤ x ≤ 2) high-entropy alloys,” Materials Science and Engineering: B, Vol. 163, pp. 184–189, 2009, Elsevier Z. Sun, et al., “Thermal physical properties of high entropy alloy Al0.3CoCrFeNi at elevated temperatures,” Journal of Alloys and Compounds, Vol. 901, p. 163554, 2022, Elsevier J. Lu, et al., “Estimating the lattice thermal conductivity of AlCoCrNiFe high-entropy alloy using machine learning,” Journal of Applied Physics, Vol. 135, No. 13, 2024, AIP Publishing Ishihara Sangyo Co., Ltd., “Bulk amorphous alloy Lumilloy,” [Retrieved February 28, 2025], Internet <URL: https: / / www.ishi-hara.co.jp / assets / pdf / lumilloy.pdf> J. Zhu, and 6 others, “Ultra-low thermal conductivity and enhanced mechanical properties of high-entropy rare earth niobates (RE3NbO7, RE=Dy, Y, Ho, Er,Yb)”, Journal of the European Ceramics Society, Vol. 41, pp. 1052-1057, 2021, Elsevier J. Wu, et al., “New class of high-entropy pseudobrookite titanate with excellent thermal stability, low thermal expansion coefficient, and low thermal conductivity”, Journal of Advanced Ceramics, Vol. 11, No. 1654, page 1670, 2022, Springer. ,
[0013] In one aspect, the present invention aims to provide an amorphous, high-entropy alloy exhibiting low thermal conductivity.
[0014] According to one aspect of the following disclosure, a high-entropy alloy is composed of the elements C, O, Al, Ti, V, Cr, Fe, Cu, Y, Zr, Nb, Ta, and W, with the content (at%) of each element being: C: 3.73 to 5.22, O: 5.82 to 8.66, Al: 2.01 to 3.04, Ti: 2.47 to 3.08, V: 5.9 to 7.6, Cr: 7.17 to 10.43, Fe: 1.03 to 1.87, Cu: 9.19 to 16.36, Y: 4.45 to 6.38, Zr: 5.18 to 6.89, Nb: 5.03 to 6.46, Ta: 13.91 or higher It is an amorphous state that satisfies either the first condition of being 20.21 or less above and W: 17.62 or more and 22.23 or less, or the second condition of being 3.86 or more and 5.87 or less, O: 1.4 or more and 3.19 or less, Al: 1.45 or more and 3.38 or less, Ti: 2.08 or more and 3.69 or less, V: 5.04 or more and 7.93 or less, Cr: 6.85 or more and 9.49 or less, Fe: 1.04 or more and 1.37 or less, Cu: 8.91 or more and 11.51 or less, Y: 1.94 or more and 4.38 or less, Zr: 5.17 or more and 6.95 or less, Nb: 4.78 or more and 6.66 or less, Ta: 18.19 or more and 22.49 or less, and W: 22.23 or more and 29.72 or less.
[0015] The above high-entropy alloy may also be in the form of a film.
[0016] According to another aspect of the following disclosure, a film forming apparatus includes: a target having, on a surface thereof, sections divided for each of a plurality of elements contained in a high-entropy alloy, with atoms of each of the plurality of elements exposed in each of the sections; a holder that is disposed at a position facing the target and holds a substrate on which a high-entropy alloy film containing the respective atoms scattered from the surface by sputtering is formed; and a mask that is disposed between the target and the substrate holder and has holes through which the respective atoms pass toward the substrate.
[0017] The film forming apparatus may further include a control unit that performs control to move the mask along the surface of the substrate and control to stop the movement of the mask.
[0018] In the film forming apparatus, the control unit may form the high-entropy alloy films with different contents of each of the plurality of elements in different regions of the substrate by repeating the movement and the stop.
[0019] In the film forming apparatus, the control unit may perform control to bring the mask around the holes into close contact with the substrate when forming the high-entropy alloy on the substrate.
[0020] In the film forming apparatus, the mask may include a disk that covers the substrate, a cone that protrudes from the disk in a direction toward the substrate holder and has the hole formed at a tip end thereof, and a biasing member that biases the cone in a direction in which the cone moves away from the disk.
[0021] In the film forming apparatus, each of the sections may be a sector shape with centers aligned with each other.
[0022] In the film forming apparatus, the sections may be arranged in an order in which the group numbers of the elements in the periodic table are consecutive.
[0023] In the film forming apparatus, the target may include a plurality of regions each formed by connecting the sections of elements belonging to the same period in the periodic table, and the periods in each of the regions may be different from each other.
[0024] In the above film forming apparatus, the target may have a base material containing atoms of an element different from each of the plurality of elements and included in the high-entropy alloy film, and a plurality of plates provided on the base material each containing an atom of one of the plurality of elements, and the surface of the base material may be exposed from between the adjacent plates.
[0025] According to another aspect of the following disclosure, a method for manufacturing a high-entropy alloy film includes selecting a plurality of elements that satisfy a criterion, preparing a target having on its surface compartments divided for each of the plurality of elements, with atoms of each of the plurality of elements exposed in each of the compartments, and sputtering the surface of the target to form a high-entropy alloy film containing the respective atoms on a substrate.
[0026] In the above method for manufacturing a high-entropy alloy film, each of the compartments may be a sector shape whose centers coincide with each other.
[0027] In the above method for manufacturing a high-entropy alloy film, the compartments may be arranged in an order in which the group numbers of the elements in the periodic table are consecutive.
[0028] In the above method for manufacturing a high-entropy alloy film, the target may include a plurality of sections each formed by connecting the compartments of elements belonging to the same period in the periodic table, and the period in each of the sections may be different.
[0029] In the above method for manufacturing a high-entropy alloy film, forming the high-entropy alloy film may be performed by passing the respective atoms through holes of a mask, and depositing the respective atoms that have passed through the holes on the substrate.
[0030] In the above method for manufacturing a high-entropy alloy film, the movement and stop of the mask are repeated along the surface of the substrate, and the film forming conditions are changed for each region of the substrate, whereby the high-entropy alloy films having different respective content ratios of the plurality of elements may be formed for each of the regions.
[0031] In the method for manufacturing the high-entropy alloy film described above, the target comprises a substrate containing atoms of elements different from each of the plurality of elements that are included in the high-entropy alloy film, and a plurality of plates provided on the substrate, each containing an atom of one of the plurality of elements, wherein the surface of the substrate may be exposed between adjacent plates.
[0032] In the above-described method for producing a high-entropy alloy film, the criteria may be based on availability, toxicity, or price.
[0033] According to the present invention, it is possible to provide an amorphous, high-entropy alloy that exhibits low thermal conductivity.
[0034] Figure 1 is a partial cross-sectional side view of the film deposition apparatus according to this embodiment. Figure 2 is a perspective view of the sputtering gun according to this embodiment, seen from the target side. Figure 3 is a photograph of the substrate holder according to this embodiment. Figure 4 is a perspective view of the mask according to this embodiment. Figure 5 is a top view of the target according to this embodiment. Figure 6A is an enlarged top view of the target according to this embodiment. Figure 6B is a cross-sectional view along the line I-I in Figure 6A. Figure 7 is a diagram showing the arrangement of each section in the target according to this embodiment. Figure 8 is an enlarged plan view drawn based on a photograph of the substrate used in the experiment in this embodiment. Figure 9 is a diagram (1) showing the film deposition conditions actually used in the investigation in this embodiment. Figure 10 is a diagram (2) showing the film deposition conditions actually used in the investigation in this embodiment. Figure 11 is a diagram (1) obtained by investigating the thermal conductivity, film thickness, and element content of each high-entropy alloy film #01 to #48 deposited according to the film deposition conditions in Figures 9 and 10. Figure 12 is a graph (part 2) obtained by investigating the thermal conductivity, film thickness, and elemental content of each high-entropy alloy film #01 to #48 deposited according to the film deposition conditions of Figures 9 and 10. Figure 13 is a graph (part 3) obtained by investigating the thermal conductivity, film thickness, and elemental content of each high-entropy alloy film #01 to #48 deposited according to the film deposition conditions of Figures 9 and 10. Figure 14 is a line graph of thermal conductivity prepared based on Figures 11 to 13. Figure 15 is a 100% stacked bar graph showing the content (at%) of each element in each high-entropy alloy film with sample ID #01 to #48 in this embodiment. Figure 16 is the XRD (X-ray Diffraction) spectrum of each high-entropy alloy film #01 to #48 in this embodiment. Figure 17 is a magnified view of the vertical axis scale of Figure 16. Figure 18 is a flowchart of the method for manufacturing a high-entropy alloy film according to this embodiment.
[0035] (Embodiment) Hereinafter, embodiments of the present invention will be described with reference to the drawings. Similar elements are denoted by the same reference numerals, and their descriptions are omitted.
[0036] Figure 1 is a partial cross-sectional side view of the film deposition apparatus according to this embodiment.
[0037] This film deposition apparatus 1 is a sputtering apparatus for depositing high-entropy alloy films, and comprises a chamber 2, a sputtering gun 3, a mask 4, a substrate holder 5, a temperature control mechanism 6, an RF (Radio Frequency) power supply 8, a QCM (Quartz Crystal Microbalance) sensor 9, a gas supply pipe 13, and a control unit 18.
[0038] Chamber 2 is a container whose interior is depressurized by a vacuum pump 12, and is equipped with multiple sputter guns 3 at its bottom.
[0039] The sputtering gun 3 is a cathode electrode that holds the target 10. The number of sputtering guns 3 is not particularly limited; for example, as shown in the figure, multiple sputtering guns 3 may be provided in the chamber 2, and each sputtering gun 3 may be equipped with a target 10 of a different metal. In this case, by sputtering multiple targets 10 simultaneously, a high-entropy alloy film consisting of combinations of metals for each target 10 can be formed. Furthermore, by changing the surface area of each target 10 for each sputtering gun 3, the composition of the high-entropy alloy film can also be controlled. The detailed structure of the target 10 will be described later.
[0040] Furthermore, the sputter gun 3 extends and retracts along its longitudinal direction A by the target drive unit 14. For example, the target drive unit 14 is a drive unit that includes a motor and a gear that converts its rotational motion into translational motion. By such translational motion, the distance between the respective surfaces of the target 10 and the substrate 11 can be adjusted. This distance will be referred to below as the S-T (Surface-Target) distance.
[0041] The substrate holder 5 is a metallic disc that holds a plurality of substrates 11 and is positioned in the chamber 2 opposite the target 10. In this example, the substrate holder 5 is provided in the upper space of the chamber 2 opposite the target 10. The substrate holder 5 is fixed to the rotating shaft 7, and the substrate holder 5 rotates when the rotation drive unit 17 rotates the rotating shaft 7. The rotation drive unit 17 is, for example, a stepping motor that can finely adjust the rotation angle.
[0042] The mask 4 is provided in the chamber 2 between the target 10 and the substrate holder 5, and has holes 4a through which atoms scattered from the surface of the target 10 by sputtering can pass. As a result, atoms that pass through the holes 4a are deposited on the substrate 11, and a high-entropy alloy film can be selectively formed only on the region of the substrate 11 surface facing the holes 4a.
[0043] As described above, by rotating the rotating shaft 7, the substrate holder 5 can change which of the multiple substrates 11 it is facing the hole 4a, and sequential film deposition can be performed on multiple substrates 11. Substrates 11 that are not facing the hole 4a are in a waiting state before or after film deposition.
[0044] Furthermore, the movement of the mask 4 is controlled by the mask drive unit 15. In this example, the mask drive unit 15 drives the mask 4 along both the direction parallel to the surface of the substrate 11 and the direction normal to the surface. This allows the holes 4a to move along the surface of the substrate 11, for example, to deposit a film in different areas of the substrate 11.
[0045] Furthermore, by driving the holes 4a along the normal direction, for example, the mask 4 around the holes 4a can be brought into close contact with the substrate 11, and a film shaped to the form of the holes 4a can be formed.
[0046] The configuration of the mask drive unit 15 is not particularly limited. For example, the mask drive unit 15 may be configured with a motor and a gear that converts its rotational motion into a direction parallel to or normal to the surface of the substrate 11.
[0047] The temperature control mechanism 6 is a mechanism for cooling or heating the substrate 11. In this example, the temperature control mechanism 6 is a metallic disc with a through hole (not shown) through which the rotating shaft 7 is inserted in a rotatable state, and is fixed to the chamber 2 regardless of the rotation of the rotating shaft 7.
[0048] As an example, the temperature control mechanism 6 has a cooling section 6a and a heating section 6b. The cooling section 6a is a mechanism for cooling multiple substrates 11 that are not facing the holes 4a and are in a waiting state. In this example, the cooling section 6a includes multiple water cooling units 6c that are cooled, for example, by water cooling. By having the water cooling units 6c face the substrates 11 via the substrate holder 5, the multiple substrates 11 in the waiting state can be cooled, and these substrates 11 can be prevented from being unnecessarily heated.
[0049] Furthermore, the heating section 6b is a mechanism for heating the substrate 11 during film formation, and includes, for example, a heater unit 6d with a built-in heater. By having the heater unit 6d face the substrate 11 via the substrate holder 5, the substrate temperature during film formation can be adjusted, and the film formation parameters can be increased. Note that the timing of heating the substrate 11 is not limited to during film formation, but may be before or after film formation.
[0050] Furthermore, the upper limit of the heating temperature by the heater unit 6d is not particularly limited, and for example, the upper limit can be 1200°C. However, if safety is a concern, the upper limit may be 1000°C, more preferably 800°C.
[0051] The RF power supply 8 is a power supply that applies RF power between the metallic outer cover of each sputter gun 3 and the target 10. In this example, RF power is applied to the target 10 while maintaining the outer cover of the sputter gun 3 at ground potential.
[0052] The QCM sensor 9 receives a frequency signal S indicating the resonant frequency of the quartz crystal oscillator. Ｑ This is a sensor that outputs a certain frequency. The QCM sensor 9 is equipped with electrodes for a quartz crystal oscillator, and when the metal of the target 10 adheres to these electrodes, the resonant frequency also changes. Based on this change, the thickness of the alloy film deposited on the substrate 11 can be monitored.
[0053] The gas supply piping 13 is a pipe that supplies sputtering gas into the chamber. The type of sputtering gas is not particularly limited. For example, argon gas can be used as the sputtering gas.
[0054] The control unit 18 is a computer such as a PC (Personal Computer) that controls each part of the film deposition apparatus 1. For example, the control unit 18 controls the target drive signal S Ｔ , mask drive signal S Ｍ , heater control signal S Ｈ Rotation control signal S Ｒ Power control signal S Ｐ , voltage divider control signal S Ｇ , and the total pressure control signal S Ｃ Outputs.
[0055] Target drive signal S Ｔ This is a signal that controls the S-T distance by controlling the target drive unit 14 to move the target 10 along the longitudinal direction A. Mask drive signal S Ｍ This is a signal that controls the amount of movement of the mask 4 by controlling the mask drive unit 15.
[0056] Heater control signal S Ｈ This is a signal that controls the heating temperature of the heater unit 6d by controlling the amount of current supplied to the heater unit 6d. Rotation control signal S Ｒ This is a signal that controls the amount of rotation of the substrate holder 5 by controlling the rotation drive unit 17.
[0057] Power control signal S Ｐ This is a signal that controls the RF power of the RF power output by the RF power supply 8. Voltage divider control signal S Ｇ This is a signal output to a flow rate control device (not shown) connected to the gas supply piping 13, and is a signal that controls the partial pressure of each gas contained in the sputtered gas.
[0058] Full pressure control signal S Ｃ This is a signal that controls the opening degree of a gate valve (not shown) connected between the vacuum pump 12 and the chamber 2. This allows control of the conductance of the gate valve, and thus control of the total pressure in the chamber 2. The total pressure in the chamber 2 during film deposition is monitored by a pressure gauge (not shown), and based on this monitoring signal, the control unit 18 issues a total pressure control signal S so that the total pressure reaches the set pressure. ＣThe output may also be provided. This suppresses variations in total pressure with each film deposition, thereby improving the reproducibility of the composition of the high-entropy alloy film.
[0059] Furthermore, the control unit 18 receives the aforementioned frequency signal S Ｑ The resonant frequency of the QCM sensor 9 is monitored, and the thickness of the high-entropy alloy film deposited on the substrate 11 is estimated based on the change in that resonant frequency.
[0060] Figure 2 is a perspective view of the sputter gun 3 as seen from the target 10 side.
[0061] As shown in Figure 2, the sputtering gun 3 has a cylindrical metallic outer cover 3a. A circular opening 3b is formed in the outer cover 3a, and the surface of the target 10 is exposed through the opening 3b. Here, the target 10 is fixed to the outer cover 3a by pressing its edge with a retaining ring 23. The material of the retaining ring 23 is not particularly limited. In this embodiment, the retaining ring 23 is formed from a metallic material containing Fe (iron).
[0062] Furthermore, a gap 16 is formed between the target 10 and the opening 3b. As described above, the outer cover 3a is grounded, and RF power generated by the RF power supply 8 (see Figure 1) is applied between the edge of the opening 3b and the surface of the target 10.
[0063] Figure 3 is a photograph of the substrate holder 5 according to this embodiment.
[0064] As shown in Figure 3, the substrate holder 5 is roughly circular in plan view, and a plurality of holders 5a for holding the substrate 11 are provided along the circumference.
[0065] Figure 4 is a perspective view of the mask 4 according to this embodiment.
[0066] As shown in Figure 4, the mask 4 comprises a disk 4b, a cone 4c, and an arm 4d.
[0067] The disk 4b is a metallic disc that covers the substrate 11 to be deposited from below. By covering the substrate 11 with the disk 4b during film deposition, it is possible to prevent the alloy film from being deposited on parts of the substrate 11 other than the holes 4a. The size of the disk 4b is not particularly limited as long as it is large enough to cover the substrate 11, and can have a diameter of, for example, 10 mm to 150 mm. The diameter of the disk 4b may be made even larger by enlarging the chamber 2.
[0068] The cone 4c is a tapered, hollow metal member that protrudes from the center of the disk 4b toward the substrate holder 5 (see Figure 1), and the aforementioned hole 4a is formed at its tip. The shape of the hole 4a is not particularly limited, but in this example, the hole 4a is rectangular in plan view. This allows a rectangular alloy film to be formed on the substrate 11 in plan view. The size of the hole 4a is also not particularly limited; for example, the hole 4a can be formed as a square with a side length of about 1 mm.
[0069] Furthermore, the inner diameter of the cone 4c narrows as it moves from the disk 4b toward the substrate holder 5 (see Figure 1). This allows atoms scattered from the target 10 by sputtering to be collected at the tip of the cone 4c, thereby accelerating the deposition rate of the alloy film. The dimensions of each part of the cone 4c are not particularly limited. For example, the height of the cone 4c can be 5 mm or more and 30 mm or less. The diameter of the base end of the cone 4c can be 10 mm or more and 150 mm or less, and the diameter of the tip of the cone 4c can be less than or equal to the diameter of the base end, 10 mm or more and 150 mm or less.
[0070] Furthermore, as shown in the enlarged circle, a spring is provided as a biasing member 4e between the base end of the cone 4c and the disk 4b. The biasing member 4e biases the cone 4c in a direction away from the disk 4b so that a gap S is formed between the disk 4b and the cone 4c. As a result, when the mask 4 is in close contact with the substrate 11 under the control of the mask drive unit 15, the gap S is reduced, which reduces the force applied from the mask 4 to the substrate 11 around the hole 4a and suppresses the high-entropy alloy film from seeping out around the hole 4a.
[0071] Figure 5 is a top view of the target 10 according to this embodiment.
[0072] As mentioned above, the chamber 2 is equipped with multiple sputtering guns 3 (see Figure 1), but in the following, only one sputtering gun 3 located directly below the hole 4a will be used. In this case, in order to form a high-entropy alloy film with only one target 10, the target 10 is constructed from multiple metals.
[0073] In the example shown in Figure 5, target 10 is roughly circular when viewed from above and has multiple sector-shaped sections with coincident centers. Hereafter, each section will be identified by the IDs "#1", "#2", "#3", ..., "#24". Each sector is obtained by dividing the circle into 24 sections, and the central angle of all sectors is the same at 15°.
[0074] The element symbols next to the compartments are the element symbols of the metal atoms exposed on the surface of the target 10 in that compartment. The method for selecting each element is not particularly limited. For example, elements that meet any of the following criteria may be selected: availability, toxicity, and price. Availability can be measured by the abundance of the element, and the greater the abundance, the more readily available the element is. Here, the Clarke number, which indicates the abundance of an element, is used as the basis for the Clarke number, and an example is given in which 10 elements are selected, with a Clarke number of 10 or more: Al (aluminum), Ti (titanium), V (vanadium), Cr (chromium), Cu (copper), Y (yttrium), Zr (zirconium), Nb (niobium), Ta (tantalum), and W (tungsten). In this case, a high-entropy alloy film containing at least these 10 elements is formed. In this embodiment, the Clarke number is taken from the value in "Chemical Handbook: Basic Edition" (edited by the Chemical Society of Japan, Maruzen, 1966).
[0075] Furthermore, the diameter of target 10 is not limited, but in the following, we will assume that the diameter of target 10 is 2 inches.
[0076] By using a single target divided into sections in this way, a high-entropy alloy film containing atoms from each section can be easily formed without using multiple targets for each atom.
[0077] Figure 6A is an enlarged top view of the target 10. As shown in Figure 6A, the target 10 comprises a plurality of fan-shaped metal plates 22, and the aforementioned sections are defined by the contours of each metal plate 22. Each metal plate 22 is a plate containing atoms of the element corresponding to each section. For example, the metal plate 22 corresponding to the Al section is a plate containing Al atoms. The Al atom content in the metal plate 22 is not particularly limited, but if the metal plate 22 contains a large amount of impurity atoms other than Al, many impurity atoms will inevitably be mixed into the high-entropy alloy film. In order to reduce the amount of impurity atoms contained in the high-entropy alloy film as much as possible, it is preferable that the metal plate 22 corresponding to the Al section contains 99.9% by weight or more Al. The same applies to the other sections, and it is preferable that the metal plates 22 other than Al contain 99.9% by weight or more of any of Ti, V, Cr, Cu, Y, Zr, Nb, Ta, and W.
[0078] Figure 6B is a cross-sectional view taken along the line I-I in Figure 6A. As shown in Figure 6B, the target 10 comprises a support plate 19, a base 21, and a plurality of metal plates 22.
[0079] The support plate 19 is a plate that supports multiple metal plates 22. The material of the support plate 19 is not particularly limited, but it is preferable to use a metal plate with excellent mechanical strength as the support plate 19. In this example, a copper plate with a thickness of 1 mm or more and 6 mm or less, for example 3 mm, is used as the metal plate 22. The lower limit of the thickness of the support plate 19 is set to 1 mm because if it is thinner than this, the support plate 19 will warp, and the flatness of the target 10 will be impaired. The upper limit of the thickness of the support plate 19 is set to 6 mm because if it is thicker than this, it will be difficult to attach the target 10 to the sputter gun 3 (see Figure 2).
[0080] Furthermore, the base material 21 is a double-sided tape for attaching multiple metal plates 22 to the support plate 19. In this example, by using a base material 21 containing atoms of different elements from each of the multiple metals in each section of the target 10, atoms not present in the target 10 are incorporated into the high-entropy alloy film. For example, the atoms contained in the base material 21 include C (carbon). In the following, Nissin EM's SEM carbon double-sided tape is used as the C-containing double-sided tape.
[0081] The thickness of each metal plate 22 is not particularly limited; for example, a metal plate 22 of 0.1 mm or more and 5 mm or less, for example, a metal plate 22 of 2 mm can be used. By setting the thickness of the metal plates 22 within this range, the target 10, which is made up of the support plate 19 and the metal plates 22, can be housed inside the sputter gun 3 (see Figure 2).
[0082] In this example, by slightly separating the sides of each metal plate 22 without making close contact, as shown within the dotted circle, the surface 21a of the substrate 21 is exposed between adjacent metal plates 22. As a result, the surface 21a is also exposed to the sputtering gas, allowing carbon atoms contained in the substrate 21 to be incorporated into the high-entropy alloy film, thereby realizing a high-entropy alloy film containing even more atoms than the constituent atoms of the target 10.
[0083] The spacing d between each metal plate 22 is not particularly limited, but in this example, the spacing d is set to 1 μm or more and 500 μm or less, for example, 30 μm. The reason the lower limit of the spacing d is 1 μm is that it is difficult to make the spacing d narrower than this considering the surface roughness of the sides of the metal plates 22. The reason the upper limit of the spacing d is 500 μm is that it is difficult to attach the target 10 to the sputter gun 3 (see Figure 2) if the spacing d is wider than this.
[0084] Next, we will explain the arrangement of each section in target 10.
[0085] Figure 7 shows the arrangement of each section in the target 10 according to this embodiment. In Figure 7, "ID" refers to the IDs "#1", "#2", "#3", ..., "#24", etc. in Figure 5. Also, "Element", "Group", and "Period" refer to the element symbol, group in the periodic table, and period of the element contained in each section, respectively.
[0086] As shown by the hatching in Figure 7, at least some of the compartments are arranged in a sequence of element group numbers in the periodic table. For example, the group numbers of the elements in compartments #2, #3, and #4 are "4", "5", and "6", respectively, and are consecutive. Elements with consecutive group numbers in this way have similar electronegativity and small differences in atomic radius. Therefore, the formation of solid solutions of each element can be expected, increasing the possibility of forming high-entropy alloy films.
[0087] Furthermore, in this example, there are regions 10a to 10d where the compartments of elements belonging to the same period in the periodic table are connected. For example, in region 10a, compartments #2 to #5 of Ti, V, Cr, and Cu, which belong to the fourth period, are connected. Similarly, in region 10b, compartments #6 to #8 of Y, Zr, and Nb, which belong to the fifth period, are connected. Regions 10c and 10d are similar. Regions 10a to 10d, which belong to different periods, are provided on the target 10.
[0088] Atoms belonging to different periods have significantly different electronegativity and atomic radii, making it easy for countless interfaces to form between them. For example, interfaces are easily formed between each atom belonging to region 10a and each atom belonging to region 10b. These interfaces dramatically improve phonon scattering, thereby inhibiting thermal conduction in the high-entropy alloy film, making it easier to form a high-entropy alloy film with low thermal conductivity.
[0089] The inventors of this application conducted experiments to actually form a high-entropy alloy on a substrate 11 using such a target 10 and to investigate its various properties.
[0090] Figure 8 is an enlarged plan view drawn based on a photograph of the substrate 11 used in the experiment.
[0091] In this study, a single-crystal silicon substrate was used as the substrate 11. Furthermore, the control unit 18 repeatedly controlled the movement and stopping of the mask 4 (see Figure 1), thereby forming a high-entropy alloy film 20 in each of the multiple regions 11a arranged in a grid pattern on the substrate 11. In Figure 8, 48 high-entropy alloy films 20 identified by sample IDs "#01", "#02", ..., "#48" are shown as examples.
[0092] Each high-entropy alloy film 20 was a square with sides of 1 mm in plan view. The spacing between adjacent high-entropy alloy films 20 was also set to 1 mm.
[0093] Next, we will explain the deposition conditions for these 48 high-entropy alloy films.
[0094] Figures 9 and 10 show the film deposition conditions actually used in the investigation in this embodiment.
[0095] As shown in Figures 9 and 10, the film deposition conditions include RF power, total pressure, and S-T distance. RF power is the RF power applied between the substrate holder 5 and the target 10 by the RF power supply 8 (see Figure 1). The frequency of the RF power was set to 13.56 MHz for all samples.
[0096] The total pressure is the pressure of the sputtering gas in chamber 2 (see Figure 1) during film deposition. The S-T distance is the distance from the surface of target 10 to the surface of substrate 11, as described above.
[0097] The RF power, total pressure, and S-T distance deposition conditions can be automatically changed by the control unit 18 for each of the 48 regions 11a (see Figure 8). This makes it possible to form a high-entropy alloy film 20 with different atomic content in each region 11a.
[0098] In this study, two S-T distances were used: 75 mm and 100 mm. For RF power, values between 50 W and 100 W were used in 10 W increments. For total pressure, four values were used: 0.005 Torr, 0.01 Torr, 0.015 Torr, and 0.02 Torr.
[0099] For sputtering, argon gas with a purity of 99.999% was used. The heater unit 6d of the temperature control mechanism 6 (see Figure 1) was not energized, and the substrate temperature during film deposition was kept at room temperature (25°C). The film deposition time was 50 minutes.
[0100] Furthermore, in Figures 9 and 10, the film deposition conditions that achieved a thermal conductivity lower than the conventional minimum value (5.4 W / (m·K)), as described later, are hatched.
[0101] Figures 11 to 13 show the thermal conductivity, film thickness, and elemental content of each of the high-entropy alloy films #01 to #48, which were deposited according to the deposition conditions shown in Figures 9 and 10.
[0102] A frequency-domain thermoreflectance microscope (Science Edge, InFocus κ FDTR) was used to evaluate thermal conductivity. The thermal conductivity values are those obtained at room temperature (25°C). A high-resolution Schottky scanning electron microscope (Hitachi High-Tech, SU3800SE) was used to evaluate elemental content. Film thickness was measured using the frequency signal S output from the QCM sensor 9 (see Figure 1). Ｑ It was calculated based on the following.
[0103] In Figures 11 to 13, sample IDs that exhibited a thermal conductivity lower than that of Lumilloy® LZR55 (5.4 W / (m·K)) at room temperature (25°C) are hatched. As mentioned above, Lumilloy® LZR55 is, to the best of the applicant's knowledge, the alloy with the lowest thermal conductivity known to date.
[0104] Figure 14 is a line graph of thermal conductivity at room temperature (25°C) prepared based on Figures 11 to 13. The horizontal axis of the line graph shows the sample ID, and the right vertical axis shows the thermal conductivity. Figure 14 also includes bar graphs of thermal permeability for each sample, with the left vertical axis of Figure 14 showing the thermal permeability. A scanning probe microimaging system (STPM-1000, manufactured by Advance Engineering) was used to evaluate the thermal permeability.
[0105] Note that the data for sample ID #49 is from a silicon single crystal substrate on which the high-entropy alloy film 20 has not been formed.
[0106] Furthermore, for the high-entropy alloy films 20 with sample IDs #40 and #47, measurement errors occurred in the FDTR, so the thermal conductivity measurements have been omitted. In addition, for the high-entropy alloy films 20 with sample IDs #25 and #40, discharge defects occurred during film formation, resulting in significant changes in the content of each element compared to the other high-entropy alloy films 20. Therefore, in the following, the high-entropy alloy films with sample IDs #25, #40, and #47 will not be evaluated.
[0107] As shown in Figure 14, in the high-entropy alloy films 20 with sample IDs #01 to #12, #27 to #30, #32, and #34, we were able to achieve a thermal conductivity lower than that of Lumilloy® LZR55 (5.4 W / (m·K)).
[0108] According to Figures 11 to 13, the high-entropy alloy films 20 with sample IDs #01 to #12, #27 to #30, #32, and #34 consist of the elements C, O, Al, Ti, V, Cr, Fe, Cu, Y, Zr, Nb, Ta, and W. Of these, C originates from the substrate 21. O (oxygen) originates from the oxidation of the high-entropy alloy film 20 when the chamber 2 was opened to the atmosphere after film formation. Fe (iron) originates from the Fe contained in the retaining ring 23 (see Figure 2) being sputtered and incorporated into the high-entropy alloy film 20. The remaining Al, Ti, V, Cr, Cu, Y, Zr, Nb, Ta, and W originate from the sputtering target 10 (see Figure 5).
[0109] Furthermore, according to Figure 11, in the high-entropy alloy films 20 with sample IDs #01 to #12, the content (at%) of each element satisfies the following first condition.
[0110] <First condition> C: 3.73 to 5.22, O: 5.82 to 8.66, Al: 2.01 to 3.04, Ti: 2.47 to 3.08, V: 5.9 to 7.6, Cr: 7.17 to 10.43, Fe: 1.03 to 1.87, Cu: 9.19 to 16.36, Y: 4.45 to 6.38, Zr: 5.18 to 6.89, Nb: 5.03 to 6.46, Ta: 13.91 to 20.21, and W: 17.62 to 22.23.
[0111] On the other hand, according to Figures 12 and 13, in the high-entropy alloy films 20 with sample IDs #27 to #30, #32, and #34, the content (at%) of each element satisfies the following second condition.
[0112] <Second condition> C: 3.86 to 5.87, O: 1.4 to 3.19, Al: 1.45 to 3.38, Ti: 2.08 to 3.69, V: 5.04 to 7.93, Cr: 6.85 to 9.49, Fe: 1.04 to 1.37, Cu: 8.91 to 11.51, Y: 1.94 to 4.38, Zr: 5.17 to 6.95, Nb: 4.78 to 6.66, Ta: 18.19 to 22.49, and W: 22.23 to 29.72.
[0113] A high-entropy alloy film 20 that satisfies either the first or second condition described above exhibits a thermal conductivity even lower than that of Lumilloy® LZR55 (5.4 W / (m·K)), which is the alloy with the lowest thermal conductivity known to date.
[0114] On the other hand, according to Figures 11 to 13, the high-entropy alloy films 20 with sample IDs #13 to #24, #26, #31, #33, #35 to #39, #41 to #46, and #48, which do not satisfy either the first or second condition, have a thermal conductivity higher than 5.4 W / (m·K).
[0115] These results demonstrate that by forming a high-entropy alloy film 20 that satisfies either the first or second condition, it is possible to provide a high-entropy alloy film 20 with a thermal conductivity at room temperature lower than the conventional lowest value (5.4 W / (m·K)).
[0116] Moreover, in both the first and second conditions, of the 13 elements (C, O, Al, Ti, V, Cr, Fe, Cu, Y, Zr, Nb, Ta, and W) contained in the high-entropy alloy film 20, only Y is a rare earth element. Therefore, the ceramics of Non-Patent Literature 6 ((Dy) in which all six elements other than oxygen are rare earth elements ０．２ Ho ０．２ Er ０．２ Y ０．２ Yb ０．２ ) ３ NboO ７ In comparison to the above, this embodiment makes it possible to reduce the cost of the high-entropy alloy 20. Furthermore, Y contained in the high-entropy alloy 20 has a Clark number of 30, and is abundant and inexpensive among rare earth elements. Therefore, the high-entropy alloy 20 can be made cost-effective despite containing rare earth elements.
[0117] Figure 15 is a 100% stacked bar graph showing the content (at%) of each element in the high-entropy alloy films 20 with sample IDs #01 to #48.
[0118] As shown in Figure 15, the high-entropy alloy films 20 with sample IDs #25 and #40 have extremely high Nb and Cr content compared to the other samples. This is because, as mentioned above, discharge defects occurred during film formation.
[0119] Figure 16 shows the XRD (X-ray Diffraction) spectra of each high-entropy alloy film 20, #01 to #48. In Figure 16, the horizontal axis represents the X-ray diffraction angle (2θ), and the vertical axis represents the intensity of the diffracted X-rays.
[0120] This XRD spectrum was acquired using a Rigaku SmartLab. A CuKα tube was used, with an X-ray output of 45 kV and 200 mA. A divergence slit of 0.5 mm was used, and a high-speed two-dimensional X-ray detector (PILATUS 100K / R) was employed. The scanning range for the diffraction angle 2θ was between 5° and 90°, and the readout width for the diffracted X-rays was 0.02°.
[0121] As shown in Figure 16, diffraction peaks from the (400) plane of silicon and the (111) plane of gold appeared in the XRD spectrum. Of these, the diffraction peak from the (400) plane of silicon originates from the single-crystal silicon substrate used as the substrate 11 for each sample. The diffraction peak from the (111) plane of gold originates from the gold coated on the surface of the high-entropy alloy film 20 for thermal conductivity evaluation.
[0122] Figure 17 is a magnified view of the vertical axis scale in Figure 16.
[0123] As shown in Figure 17, even when the vertical axis scale was magnified, diffraction peaks originating from silicon and gold could be confirmed, but diffraction peaks originating from the crystal composed of atoms contained in target 10 could not be detected. Furthermore, based on the following papers 1 and 2, the diffraction peak at 61.3 degrees is thought to originate from the (411) plane of polycrystalline silicon formed when the silicon single crystal substrate was laser-cut.
[0124] (Paper 1) Y. C. Lam, et al., “Seeing the invisible laser markings”, Journal of Physics D: Applied Physics, Vol. 42, No. 042004, 2009, IOP Publishing
[0125] (Paper 2) J. Z. Hu, et al., “Crystal data for high-pressure phases of silicon”, Physical Review B, Vol. 34, No. 4679, 1986, APS.
[0126] Thus, in all of the high-entropy alloy films #01 to #48, no diffraction peaks originating from crystals composed of atoms contained in target 10 were detected. From this, it was found that all high-entropy alloy films #01 to #48 were in a metastable amorphous state and were actually in a high-entropy state. Due to this effect, it is thought that high-entropy alloys exhibiting lower thermal conductivity than conventional films could be deposited, as mentioned above.
[0127] Furthermore, because it exhibits low thermal conductivity in an amorphous state, annealing for crystallization is unnecessary in this embodiment, as described in Non-Patent Documents 6 and 7. Therefore, a high-entropy alloy film 20 with low thermal conductivity can be manufactured easily and at low cost.
[0128] Next, a method for producing a high-entropy alloy film according to this embodiment will be described.
[0129] Figure 18 is a flowchart of the method for manufacturing a high-entropy alloy film according to this embodiment.
[0130] First, several elements that make up the high-entropy alloy film are selected (step S11). For example, criteria are predetermined regarding availability, toxicity, and price, and elements that meet those criteria are selected.
[0131] Next, a target 10 containing atoms of the selected element is fabricated (step S12). For example, as shown in Figures 6A and 6B, multiple fan-shaped metal plates 22 are fabricated for each selected element. Then, each metal plate 22 is attached to the support plate 19 via a base 21 to complete a target 10 with a circular planar shape (see Figure 5).
[0132] Next, a high-entropy alloy film 20 containing each of the selected elements is formed on the substrate 11 by sputtering using the target 10 (step S13). At this time, as shown in Figure 8, the high-entropy alloy film 20 with different atomic content may be formed in multiple regions 11a of the substrate 11.
[0133] Alternatively, a single high-entropy alloy film 20 having a predetermined atomic content may be deposited in only one region of the substrate 11. In this case, the high-entropy alloy film 20 is deposited under deposition conditions such that the atomic content satisfies either condition 1 or condition 2 described above. Such deposition conditions correspond to sample IDs #01 to #12, #27 to #30, #32, and #34, which are hatched in Figures 9 and 10. This makes it possible to realize a high-entropy alloy film 20 with a thermal conductivity lower than the conventional minimum value (5.4 W / (m·K)).
[0134] This concludes the basic steps of the method for manufacturing a high-entropy alloy film according to this embodiment. With this manufacturing method, by using a single target 10 divided into sections as shown in Figure 5, a high-entropy alloy film containing atoms in each section can be easily formed without using multiple targets for each atom.
[0135] Furthermore, by controlling the film deposition conditions, it is possible to deposit high-entropy alloy films with a thermal conductivity lower than the conventional minimum value (5.4 W / (m·K)), as shown in the measurement results in Figures 11 to 17.
[0136] The applications of the high-entropy alloy film are not particularly limited; for example, the high-entropy alloy may be used as a thermal insulation material. This thermal insulation material can be used, for example, to insulate window glass or infrared sensors. Alternatively, the high-entropy alloy film may be formed into a bulk material, and this bulk high-entropy alloy may be used as the thermal insulation material.
[0137] 1...Film deposition apparatus, 2...Chamber, 3...Sputter gun, 3a...Outer cover, 3b...Opening, 4...Mask, 4a...Hole, 4b...Disk, 4c...Cone, 4d...Arm, 4e...Biasing member, 5...Substrate holder, 6...Temperature control mechanism, 6a...Cooling unit, 6b...Heating unit, 6c...Water cooling unit, 6d...Heater unit, 7...Rotating shaft, 8...RF power supply, 9...QCM sensor, 10...Target, 11...Substrate, 12...Vacuum pump, 13...Gas supply piping, 14...Target drive unit, 15...Mask drive unit, 16...Gap, 17...Rotation drive unit, 18...Control unit, 20...High-entropy alloy film, 21...Undercoat, 22...Metal plate, 23...Pressing ring.
Claims
1. It consists of each of the elements C, O, Al, Ti, V, Cr, Fe, Cu, Y, Zr, Nb, Ta, and W, and satisfies the first condition that the content (at%) of each of the elements is: C: 3.73 to 5.22, O: 5.82 to 8.66, Al: 2.01 to 3.04, Ti: 2.47 to 3.08, V: 5.9 to 7.6, Cr: 7.17 to 10.43, Fe: 1.03 to 1.87, Cu: 9.19 to 16.36, Y: 4.45 to 6.38, Zr: 5.18 to 6.89, Nb: 5.03 to 6.46, Ta: 13.91 to 20.21, and W: 17.62 to 22.23, or Amorphous high-entropy alloy satisfying the second condition of C: 3.86 to 5.87, O: 1.4 to 3.19, Al: 1.45 to 3.38, Ti: 2.08 to 3.69, V: 5.04 to 7.93, Cr: 6.85 to 9.49, Fe: 1.04 to 1.37, Cu: 8.91 to 11.51, Y: 1.94 to 4.38, Zr: 5.17 to 6.95, Nb: 4.78 to 6.66, Ta: 18.19 to 22.49, and W: 22.23 to 29.
72.
2. The high-entropy alloy according to claim 1, which is in the form of a film.
3. A film deposition apparatus comprising: a target having compartments on its surface divided according to a plurality of elements contained in a high-entropy alloy, with each of the atoms of the plurality of elements exposed in each of the compartments; a holder provided opposite the target and holding a substrate on which a high-entropy alloy film containing each of the atoms scattered from the surface by sputtering is formed; and a mask provided between the target and the substrate holder, with holes formed therein for each of the atoms to pass toward the substrate.
4. The film deposition apparatus according to claim 3, further comprising a control unit that controls the movement of the mask along the surface of the substrate and controls the movement of the mask.
5. The film-forming apparatus according to claim 4, wherein the control unit repeats the movement and stopping to form the high-entropy alloy film, in which the respective content of the plurality of elements differs, in different regions of the substrate.
6. The film deposition apparatus according to claim 4 or 5, wherein the control unit controls the mask around the holes to be in close contact with the substrate when forming the high-entropy alloy on the substrate.
7. The film deposition apparatus according to claim 6, wherein the mask comprises a disk covering the substrate, a cone protruding from the disk toward the substrate holder and having the hole formed at its tip, and a biasing member that biases the cone toward away from the disk.
8. The film deposition apparatus according to any one of claims 3 to 7, wherein each of the aforementioned sections is a sector with its respective center coinciding.
9. The film deposition apparatus according to any one of claims 3 to 8, wherein the compartments are arranged in a sequence in which the group numbers of the elements in the periodic table are consecutive.
10. The film deposition apparatus according to any one of claims 3 to 9, wherein the target comprises a plurality of regions in which the sections of elements belonging to the same period in the periodic table are connected, and the period in each of the regions is different.
11. The film-forming apparatus according to any one of claims 3 to 10, wherein the target comprises a substrate containing atoms of elements different from each of the plurality of elements, and a plurality of plates provided on the substrate, each containing an atom of one of the plurality of elements, and the surface of the substrate is exposed between adjacent plates.
12. A method for manufacturing a high-entropy alloy film, comprising: selecting a plurality of elements that meet a standard; creating a target having compartments on its surface divided according to the plurality of elements, with each of the atoms of the plurality of elements exposed in each of the compartments; and forming a high-entropy alloy film containing each of the atoms on a substrate by sputtering the surface of the target.
13. The method for manufacturing a high-entropy alloy film according to claim 12, wherein each of the aforementioned sections is a sector with its respective center coinciding.
14. A method for producing a high-entropy alloy film according to claim 12 or claim 13, wherein the compartments are arranged in a sequence in which the group numbers of the elements in the periodic table are consecutive.
15. The method for manufacturing a high-entropy alloy film according to any one of claims 12 to 14, wherein the target comprises a plurality of regions in which the sections of elements belonging to the same period in the periodic table are connected, and the period in each of the regions is different.
16. The method for producing a high-entropy alloy film according to any one of claims 12 to 15, wherein the high-entropy alloy film is formed by passing each of the atoms through holes in a mask and depositing each of the atoms that have passed through the holes onto the substrate.
17. A method for producing a high-entropy alloy film according to claim 16, wherein the high-entropy alloy film, in which the respective content of the plurality of elements differs, is formed in each region by repeatedly moving and stopping the mask along the surface of the substrate and changing the film formation conditions for each region of the substrate.
18. A method for manufacturing a high-entropy alloy film according to any one of claims 12 to 17, wherein the target comprises a substrate containing atoms of elements different from each of the plurality of elements, and a plurality of plates provided on the substrate, each containing an atom of one of the plurality of elements, with the surface of the substrate exposed between adjacent plates.
19. A method for producing a high-entropy alloy film according to any one of claims 12 to 18, wherein the criterion is a criterion relating to availability, toxicity, or price.