Target and method for producing target

Abstract

The present invention provides: a target which is suitable for the production of a delafossite-type oxide thin film; and a method for producing the target. The target includes 45 at% or more and 90 at% or less of a first metal, with the balance being made up of a second metal and impurities. The first metal is palladium or platinum, the second metal is cobalt, chromium or rhodium, the content of impurities is 500 mass ppm or less, and the content of oxygen as an impurity is 200 mass ppm or less.

Description

Target and method for manufacturing the target

[0001] The present disclosure relates to targets and methods for making targets.

[0002] Patent Document 1 discloses a cobalt or cobalt-based alloy sputtering target and a method for manufacturing the same. This target has an average PTF (magnetic leakage flux) of 75% or more in the direction perpendicular to the sputtering surface when measured at a thickness of 3 mm, and a standard deviation of the PTF in the direction perpendicular to the sputtering surface of 5% or less. This target has a composition consisting of Co and unavoidable impurities, or contains one or more elements selected from the group consisting of Pt, Cr, Ni, Fe, Pd, Ir, Ru, B, Si, Ge, Mn, Ti, Zr, V, and Ta. Furthermore, this manufacturing method is also applicable to a semiconductor device having a composition consisting of Co and unavoidable impurities, or containing one or more elements selected from the group consisting of Pt, Cr, Ni, Fe, Pd, Ir, Ru, B, Si, Ge, Mn, Ti, Zr, V, and Ta, wherein the contents of each element are Pt: 5 mass% or less, Cr: 5 mass% or less, Ni: 25 mass% or less, Fe: 9 mass% or less, Pd: 25 mass% or less, Ir: 25 mass% or less, Ru: 25 mass% or less, B: 0.5 mass% or less, Si: 2 mass% or less, Ge: 18 mass% or less, Mn: 25 mass% or less, and Ti: 2 mass%. The method includes the steps of preparing a raw material powder having a composition of 1% by mass or less Zr, 1.5% by mass or less V, and 3% by mass or less Ta, with the remainder being Co and unavoidable impurities, and having a volumetric D10 of 10 μm or more and a D90 of 150 μm or less as measured by a laser diffraction method, and molding the raw material powder into a desired target shape by an additive manufacturing method under the conditions of a preheating temperature of 600 to 900°C, an electron beam acceleration voltage of 50 to 70 kV, a modeling layer thickness of 50 to 100 μm / layer, and a beam scan speed of 500 to 5,000 m / s. One example of the additive manufacturing method is powder bed fusion (PBF), which involves repeatedly heating the surface of a powder bed using electron beam melting (EBM) or laser melting (SLM) to selectively melt and solidify it, thereby forming the powder into a desired target shape.

[0003] Patent Document 2 describes a method for producing a sputtering target material. This production method is for a sputtering target material made of a magnetic alloy obtained by hot solidifying and molding powder, using a powder raw material composed of at least one element selected from the group of elements consisting of Fe, Co, and Ni, which are elements of Group 8A of the periodic table in period 4, or at least one element selected from the group of elements consisting of Fe, Co, and Ni, which are elements of Group 8A of the periodic table in period 4, in a total amount of 60 at. % or more as the main component, with the remainder being at least one element selected from the group consisting of Al, Ag, Au, B, C, Ce, Cr, Cu, Ga, Ge, Dy, Gd, Hf, In, La, Mn, Mo, Nb, Nd, P, Pd, Pt, Ru, Si, Sm, Sn, Ta, Ti, V, W, Y, Zn, and Zr, and unavoidable impurities, the sputtering target material is produced by solidifying and molding the powder and then cooling it to 300°C at a cooling rate of 144 to 36,000°C / hr. Patent Document 2 discloses a target containing Co as the main component and 1 at% Pd, and a target containing Co as the main component and 1 at% Pt.

[0004] For example, as disclosed in Patent Document 3, demand for power devices (also referred to as power semiconductors, power elements, or power semiconductor elements) used in power converters such as inverters and converters is increasing due to, for example, the spread of electric vehicles (EVs). Gallium oxide, for example, is known as an oxide for power devices.

[0005] Non-Patent Document 1 states that PdCoO ２ A case has been disclosed in which a large Schottky barrier of 1.8 eV was realized in a thin film. ２ The thin film was produced by pulsed laser deposition. ２ and β-Ga ２ O ３ Like the interface with PdCoO ２At the interface between the oxide and the thermally stable oxide, a polar layered structure electric dipole is naturally formed. Therefore, even in a high temperature environment such as 350°C, ８ It has been shown that current rectification can be achieved with a large on / off ratio approaching the order of 1000. Furthermore, Non-Patent Document 1 discloses that there is a great demand for semiconductor devices to operate at high temperatures for switching and sensing applications in the technical fields of automobiles, plants, and aerospace.

[0006] JP 2017-119904 A JP 2011-208265 A International Publication No. 2020 / 090491

[0007] Electric dipole effect in PdCoO2 / β-Ga2O3 Schottky diodes for high-temperature operation, Harada et al, Science Advances 5, eaax5733 (2019)

[0008] As disclosed in Patent Document 3, gallium oxide has a large band gap, a large breakdown field, and high thermal stability and excellent chemical resistance, making it an excellent semiconductor for power devices, and demand for it in power device applications is expected to increase. However, conventionally used Schottky electrodes using platinum, for example, have a small Schottky barrier and are insufficient in terms of heat resistance and reliability (voltage resistance) in applications where excellent power device semiconductors such as gallium oxide are used, such as applications requiring high output.

[0009] Here, palladium cobalt oxide (PdCoO ２ ), and palladium chromium oxide (PdCrO), which is a delafossite-type oxide similar to palladium cobalt oxide. ２ ), palladium rhodium oxide (PdRhO ２ ) or platinum cobalt oxide (PtCoO ２Despite being an oxide, gallium monoxide (GMO) exhibits high electrical conductivity comparable to that of elemental metals such as gold, silver, and copper. Therefore, it is expected to be used as a Schottky electrode for power devices, similar to that of gallium oxide.

[0010] In semiconductor devices, electrodes are formed by depositing a film of an electrode material by, for example, sputtering. Therefore, as disclosed in, for example, Patent Documents 1 and 2, sputtering targets suitable for producing desired thin films have been studied. However, conventional techniques have not been able to provide targets suitable for depositing the above-mentioned delafossite-type oxide film. For example, with conventional targets, a large amount of particles may be generated during the formation of a delafossite-type oxide thin film, or unwanted oxides may be generated, preventing the crystal structure of the delafossite-type oxide from being established. Therefore, it is desirable to provide a target suitable for producing a delafossite-type oxide thin film.

[0011] The present disclosure has been made in view of the above circumstances, and an object of the present disclosure is to provide a target suitable for producing a delafossite-type oxide thin film and a method for producing the same.

[0012] In order to achieve the above object, the target according to the present disclosure contains a first metal in an amount of 45 at% or more and 90 at% or less, with the remainder being a second metal and impurities, the first metal being palladium or platinum, the second metal being cobalt, chromium or rhodium, the content of the impurities being 500 ppm by mass or less, and the content of oxygen as the impurity being 200 ppm by mass or less.

[0013] In order to achieve the above object, a method for manufacturing a target according to the present disclosure includes a step of sintering a metal powder containing 45 at% or more and 90 at% or less of a first metal, with the remainder being a second metal and impurities, wherein the content of the impurities is 500 ppm by mass or less, and the content of oxygen as the impurity is 200 ppm by mass or less.

[0014] According to the present disclosure, it is possible to provide a target suitable for producing a delafossite-type oxide thin film and a method for producing the same.

[0015] 5 is a palladium mapping image obtained by SEM-EDX of the target according to Example 1. FIG. 6 is a cobalt mapping image obtained by SEM-EDX of the target according to Example 1. FIG. 7 is a binarized image of the mapping image shown in FIG. 2. FIG. 8 is a palladium mapping image obtained by SEM-EDX of the target according to Example 2. FIG. 9 is a cobalt mapping image obtained by SEM-EDX of the target according to Example 2. FIG. 10 is a binarized image of the mapping image shown in FIG. 5. FIG. 11 is an X-ray diffraction pattern of a thin film deposited using the target according to Example 1. FIG. 12 is an X-ray diffraction pattern of a thin film deposited using the target according to Example 2.

[0016] A target and a method for manufacturing a target according to an embodiment of the present disclosure will be described with reference to the drawings. First, an overview of the target and the method for manufacturing a target according to the present embodiment will be described.

[0017] The target according to this embodiment contains a first metal at 45 at % or more and 90 at % or less, with the remainder being a second metal and impurities. The first metal is palladium or platinum. The second metal is cobalt, chromium, or rhodium. The impurity content is 500 ppm by mass or less, and the oxygen content as an impurity is 200 ppm by mass or less. Note that "at %" refers to an element ratio expressed in percentage.

[0018] The target according to this embodiment is suitable for producing a delafossite-type oxide thin film.

[0019] The target according to this embodiment can be produced by, for example, a production method including a step of sintering a metal powder containing 45 at% to 90 at% of a first metal and the remainder being a second metal and impurities, wherein the metal powder has an impurity content of 500 ppm by mass or less and an oxygen content of 200 ppm by mass or less.

[0020] The target and the method for manufacturing the target according to this embodiment will be described in detail below.

[0021] The target according to this embodiment is suitable for producing a delafossite-type oxide thin film by a physical vapor deposition method (PVD method, hereinafter simply referred to as PVD) such as sputtering. The delafossite-type oxide is a compound represented by the general formula ABO ２ In this embodiment, the delafossite-type oxide is a palladium cobalt oxide (PdCoO ２ ), palladium chromium oxide (PdCrO ２ ), platinum cobalt oxide (PtCoO ２ ) and palladium rhodium oxide (PdRhO ２ ) will be explained as an example.

[0022] The target according to this embodiment includes a first metal and a second metal. The first metal is element A (monovalent cation) in the above general formula. The second metal is element B (trivalent cation) in the above general formula. The target according to this embodiment may include impurities.

[0023] The first metal is palladium (Pd) or platinum (Pt). The target contains the first metal in an amount of 45 at% to 90 at%. The target contains the first metal in an amount of preferably 45 at% to 60 at% and more preferably 50 at% to 55 at%.

[0024] The second metal is cobalt (Co), chromium (Cr), or rhodium (Rh). The target contains the second metal in an amount of 10 at% to 55 at%. The target contains the second metal in an amount of preferably 40 at% to 55 at%, more preferably 45 at% to 50 at%.

[0025] The target according to this embodiment contains the first metal and the second metal in the above ratio, making the target according to this embodiment suitable for producing a delafossite-type oxide thin film. Specifically, when a delafossite-type oxide thin film (hereinafter sometimes simply referred to as a thin film) is produced by PVD using the target according to this embodiment, the proportion of delafossite-type oxide in the thin film can be increased. In other words, the proportion of metals or metal oxides other than the delafossite-type oxide in the thin film can be reduced. This reduces the electrical resistivity when the thin film is used as an electrode, making the thin film more suitable for use as an electrode.

[0026] In this embodiment, impurities refer to elements that are not intentionally added. In the target according to this embodiment, the total amount of impurities is suppressed to 500 mass ppm or less (hereinafter simply referred to as ppm). The impurities are preferably suppressed to 300 ppm or less, and more preferably 200 ppm or less per element. In this embodiment, the impurity concentrations are values ​​measured using an ICP optical emission analyzer.

[0027] The target according to this embodiment may contain oxygen (O), nitrogen (N), carbon (C), sulfur (S), and other unavoidable impurities as impurities. Of these, the oxygen content is suppressed to 200 ppm or less. By reducing the oxygen content, it may be possible to reduce the content of metal oxides other than the delafossite-type oxide in the thin film.

[0028] The target according to this embodiment may be a sintered body of a metal powder containing a first metal and a second metal. The metal powder may be a mixed powder of a powder of the first metal and a powder of the second metal, or may be a powder of an alloy of the first metal and the second metal (hereinafter referred to as alloy powder). The metal powder is preferably an alloy powder.

[0029] When the target according to this embodiment is a sintered body, the thin film can be made homogeneous by using an alloy powder as the metal powder. A homogeneous thin film specifically refers to a state in which the distribution of delafossite-type oxide in the thin film is homogeneous, the distribution of constituent elements in the thin film is homogeneous, or the distribution of impurities in the thin film is homogeneous. In other words, a homogeneous thin film refers to a state in which, when the element distribution in the thin film is mapped using, for example, an SEM (scanning electron microscope) and an EDX (energy dispersive X-ray spectrometry), the variation in element distribution indicates that the elements are present in a solid solution state.

[0030] Here, the variation in element distribution is a variation in noise level, which means, for example, that when a cross section of a target is mapped by SEM-EDX, the size of the domain of the first metal is 5 μm or less in terms of circle-equivalent diameter. In this embodiment, the domain of the first metal is defined as a closed region on the side where the element ratio of the second metal is lower than a predetermined element ratio of the second metal (50 at % in this embodiment) when the image of the mapped second metal is binarized using the threshold value. The size of this domain is preferably 5 μm or less in terms of circle-equivalent diameter converted from the area. The size of this domain is more preferably 3 μm or less, and even more preferably 1 μm or less.

[0031] The target according to this embodiment preferably has a density of 90% or more and 99% or less. A low density of the target, i.e., a large number of voids present within the target, especially large voids, can cause abnormal discharge during PVD processes such as sputtering, leading to particle intrusion into the thin film during film formation. Increasing the density to this level suppresses particle intrusion into the thin film during PVD film formation. This makes the thin film more suitable as an electrode. The density is calculated based on the density of the alloy of the first metal and the second metal (hereinafter referred to as the alloy density), calculated based on the content ratio of the first metal to the second metal, and the apparent density of the target (hereinafter referred to as the target density). In other words, the density (%) is calculated by dividing the target density by the alloy density and multiplying the result by 100. The target density is calculated by dividing the mass of the target by the target's shape (volume).

[0032] When producing the target according to this embodiment as a sintered body, it is sufficient to sinter metal powder containing 45 at% to 90 at% of the first metal and the remainder being the second metal and impurities.When producing the target according to this embodiment as a sintered body, it is sufficient to sinter metal powder containing preferably 45 at% to 60 at% of the first metal, more preferably 50 at% to 55 at% of the first metal.

[0033] During this sintering, if the metal powder is an alloy powder containing 45 at% to 90 at% of the first metal and the remainder being the second metal and impurities, the target can be produced as a sintered body of the alloy powder. This reduces the concentration unevenness (element ratio variation, distribution variation) of the first metal and the second metal in the target. By reducing the concentration unevenness of the first metal and the second metal in the target, the thin film can be made homogeneous.

[0034] If a mixed powder of a powder of the first metal and a powder of the second metal is used as the metal powder during sintering, the target can also be produced as a sintered body of the mixed powder.

[0035] The particle size of the metal powder used for sintering, in terms of volume average diameter, is preferably 20 μm or more and 120 μm or less, and more preferably 50 μm or more and 70 μm or less. Alternatively, it may be a product that passes through a sieve with a mesh size of 106 μm. If the particle size of the metal powder is within this range, it becomes easy to manufacture a target with high density. In this embodiment, the particle size and particle size distribution of the metal powder are measured using a laser diffraction particle size distribution analyzer (manufactured by Shimadzu Corporation, model: SLDA-2300) while the metal powder is dispersed in water to which a surfactant has been added.

[0036] In particular, when the metal powder used for sintering is a mixed powder, the particle diameter of each of the first metal and second metal powders is preferably 20 μm or more and 120 μm or less in terms of volume average diameter. This may reduce the concentration unevenness (element ratio variation, distribution variation) of the first metal and the second metal in the target. By reducing the concentration unevenness of the first metal and the second metal in the target, the thin film can be made homogeneous.

[0037] The step of sintering the metal powder (hereinafter referred to as the sintering step) may be carried out according to the procedure described below.

[0038] The sintering step may include a molding step of molding the metal powder into a predetermined shape, for example, a disk shape suitable for use as a target. In the sintering step, for example, the metal powder is pressurized while being heated, so that the metal powder can be sintered while being molded into the predetermined shape.

[0039] In the sintering step, the metal powder may be sintered at a temperature of 550° C. to 1300° C. In addition, in the sintering step, the metal powder may be sintered while applying a pressure of 20 MPa to 70 MPa. This makes it possible to obtain a target with a high density, specifically a density of 90% to 99%, as a sintered body.

[0040] Example 1 A target according to Example 1 was manufactured as follows.

[0041] The alloy powder (manufactured by Tanaka Kikinzoku Kogyo Co., Ltd., volume average diameter: 60 μm) produced by gas atomization has a composition ratio of palladium and cobalt of 50:50 (the content of palladium and cobalt is approximately 50 at %), with the remainder being cobalt and impurities (the amount of impurities is 351 ppm or less, and oxygen is 25 ppm). 93 g of the alloy powder was weighed out and filled into a mold as the powder for sintering, followed by hot press sintering (the atmosphere during sintering was 5 × 10 －２ The alloy powder was prepared by weighing palladium and cobalt (both metals) so that the alloy composition ratio between them was 50:50, heating the molten alloy to 1500°C or higher, gas atomizing the molten alloy, and classifying the atomized powder using a sieve with 106 μm openings.

[0042] The sintered product was then processed to obtain a disk-shaped target for this example. The surface and sides of the disk were ground to prepare the target for subsequent use. The target after shape adjustment was disk-shaped with a diameter of 50.8 mm and a thickness t of approximately 1 mm. The pressure during sintering using the hot press sintering method (pressure applied to the powder in the mold, hereinafter referred to as the sintering pressure) was 50 MPa, and the furnace temperature during sintering (hereinafter referred to as the sintering temperature) was 700°C. The sintering time (the time during which the above sintering pressure and sintering temperature were maintained) was 60 minutes. The furnace was kept in a vacuum atmosphere during sintering.

[0043] The amounts of impurities in the target according to this example were quantified using an ICP optical emission analyzer, and the results were 21 ppm for oxygen, 3 ppm for nitrogen, 17 ppm for carbon, and 6 ppm for sulfur. The purities of palladium and cobalt were high, and a metallic (non-oxidized) target was obtained.

[0044] The elemental ratio of palladium to cobalt in the target according to this example was maintained at the same level as that in the sintering powder (alloy powder). "Maintaining the elemental ratio in the sintering powder" means that the ratio of the elemental ratio of cobalt (element B) to the elemental ratio of palladium (element A) in the sintering powder was the same as the ratio of the elemental ratio of cobalt (element B) to the elemental ratio of palladium (element A) in the target, within an error of 1%.

[0045] The density of the target according to this example was 95.9%.

[0046] 1 and 2 show a mapping image of palladium (L line) (see FIG. 1 ) and a mapping image of cobalt (K line) (see FIG. 2 ) in the target according to this example, measured using an SEM-EDX (manufactured by JEOL Ltd., model: JCM-6000Plus, magnification: 400x). In FIGS. 1 and 2 , the closer to white the image, the higher the element ratio (concentration) of the element being mapped. FIG. 3 shows a mapping image (hereinafter referred to as a binarized image) obtained by binarizing the cobalt mapping image shown in FIG. 2 based on an element ratio threshold value (50 at%). In FIG. 3 , the white areas indicate areas where the element ratio of the cobalt element being mapped is relatively higher than the threshold value. In FIG. 3 , the black areas indicate areas where the element ratio of the cobalt element is relatively lower than the threshold value, i.e., palladium (first metal) domains. The circle-equivalent diameter of the cobalt domain measured based on the binarized image of FIG. 3 was 5 μm or less. These mapping images showed almost no unevenness in the palladium or cobalt concentrations, and confirmed that the dispersion state was extremely good and that the palladium and cobalt were in a solid solution state. From these results, it was determined that the target according to this example was in a homogeneous alloyed state.

[0047] (Example 2) The target of Example 2 differs from Example 1 in that a mixed powder of palladium powder and cobalt powder was used as the sintering powder instead of the alloy powder, but was otherwise manufactured in the same manner as Example 1.

[0048] Palladium powder was prepared using a chemical reduction method with an impurity content of 245 ppm (Tanaka Kikinzoku Kogyo Co., Ltd., passed through a 106 μm sieve). Cobalt powder was prepared using a gas atomization method with an impurity content of 246 ppm. 59.85 g of palladium powder and 33.15 g of cobalt powder were weighed and mixed in a mortar for 10 minutes to obtain a mixed powder. 93 g of the mixed powder was then weighed and filled into a mold. A disk-shaped target was obtained in the same manner as in Example 1. Cobalt powder was obtained by heating cobalt to 1500°C or higher to obtain a molten metal, gas atomizing the molten metal, and then classifying the atomized powder through a 106 μm sieve.

[0049] The amounts of impurities in the target according to this example were 171 ppm oxygen, 40 ppm nitrogen, 27 ppm carbon, and 9 ppm sulfur, and the purity of palladium and cobalt was high, resulting in a target in a metallic state (not oxidized).

[0050] The element ratio between palladium and cobalt in the target according to this example was maintained at the same element ratio as in the state of the powder (mixed powder) for sintering.

[0051] The density of the target according to this example was 95.1%.

[0052] Figures 4 and 5 show mapping images of palladium (see Figure 4) and cobalt (see Figure 5) in the target of this example, measured in the same manner as in Example 1. In Figures 4 and 5, the closer to white the image, the higher the element ratio of the mapped element. These mapping images clearly show uneven palladium and cobalt concentrations. The target of this example was determined to be in a state where areas with high palladium element ratios (concentrations) and areas with high cobalt element ratios (concentrations) were mixed and dispersed. Observation of these images revealed that the domain sizes of areas with high palladium element ratios (concentrations) and areas with high cobalt element ratios (concentrations) roughly corresponded to the particle diameters of the powders used for sintering. In other words, in targets sintered using mixed powders, domains of each element corresponding to the particle diameters of the mixed powders used for sintering are believed to remain. Figure 6 is a binarized version of Figure 5, obtained in the same manner as Figure 3. The black areas indicate palladium domains where the atomic ratio of the cobalt element is relatively lower than the threshold value.

[0053] Furthermore, using the targets of Examples 1 and 2, thin films of palladium cobalt oxide were formed by reactive sputtering using RF sputtering, and the films were evaluated by X-ray diffraction.

[0054] The substrate for thin film formation is Al ２ O ３ A (0001) sapphire substrate was used, which had been annealed at 1100° C. for two hours.

[0055] The sputtering was carried out using a sputtering device (model: ESCS-232S) manufactured by Eiko Engineering Co., Ltd.

[0056] The RF output was set to 60 W. The RF frequency was 13.56 MHz.

[0057] The pressure in the chamber where the film was formed was set to 0.2 Pa.

[0058] The TS distance (the distance from the target surface of the cathode of the sputtering device to the substrate) was set to 150 mm.

[0059] For reactive sputtering, the reactive gases are argon (Ar) and oxygen (O ２ The flow rates of the reactive gases in the chamber were 4 sccm for argon and 12 sccm for oxygen.

[0060] When the target of Example 1 was used, the substrate temperature was set to 700°C. When the target of Example 2 was used, the substrate temperature was set to 600°C.

[0061] Fig. 7 shows the X-ray diffraction pattern of the thin film formed using the target according to Example 1 (a target produced using the alloy powder), and Fig. 8 shows the X-ray diffraction pattern of the thin film formed using the target according to Example 2 (a target produced using the mixed powder).

[0062] 7 and 8, the peaks of the (0003), (0006) and (0009) planes of palladium cobalt oxide are indicated by symbols a, b and c, respectively, in the X-ray diffraction patterns.

[0063] These peaks indicate that the thin films formed using the targets of Examples 1 and 2 are thin films of palladium cobalt oxide, which is a delafossite-type oxide.

[0064] 7 and 8, tricobalt tetroxide (Co ３ O ４ The peak of the (222) plane of palladium oxide (PdO) is indicated by the symbol d in the X-ray diffraction pattern. Also, in Fig. 8, the peak of the (101) plane of palladium oxide (PdO) is indicated by the symbol e in the X-ray diffraction pattern. Note that no peaks of metallic palladium (Pd) were observed in these diffraction patterns.

[0065] That is, it can be seen that the thin film deposited using the target of Example 1 contains a very small amount of tricobalt tetroxide in the thin film of palladium cobalt oxide, to the extent that a slight peak remains, and that metallic palladium or palladium oxide is not contained, or is contained only to the extent that no peak is observable.

[0066] It can be seen that the thin film deposited using the target of Example 2 contains very small amounts of tricobalt tetroxide and palladium oxide in the thin film of palladium-cobalt oxide, to the extent that only a slight peak remains, and that metallic palladium is not contained or is contained so little that no peak is observable.

[0067] Furthermore, when the element ratio of palladium to cobalt was measured using an ICP optical emission spectrometer for the thin films formed using the targets of Examples 1 and 2 (targets with a Pd:Co composition ratio of 50:50), the Pd:Co ratio was within the range of 48.8-49.0:51.2-51.0 for all the thin films, demonstrating that the thin films were homogeneous.

[0068] As described above, a target suitable for producing a delafossite-type oxide thin film and a method for producing the same can be provided.

[0069] It should be noted that the embodiments disclosed in this specification are merely examples, and the embodiments of the present disclosure are not limited to these, and can be modified as appropriate within the scope of the purpose of the present disclosure.

[0070] The present disclosure is applicable to targets and methods for manufacturing the same.

Claims

1. A target containing 45 at% or more and 90 at% or less of a first metal, the balance being a second metal and impurities, wherein the first metal is palladium or platinum, the second metal is cobalt, chromium or rhodium, the content of the impurities is 500 mass ppm or less, and the oxygen as the impurities is 200 mass ppm or less.

2. The target according to claim 1, containing 45 at% or more and 60 at% or less of the first metal.

3. The target according to claim 1 or 2, which is a sintered body of an alloy powder of the first metal and the second metal.

4. The target according to any one of claims 1 to 3, wherein the density calculated based on the content ratio of the first metal and the second metal is 90% or more and 99% or less.

5. The target according to any one of claims 1 to 4, wherein when the cross-section is mapped by SEM-EDX, the size of the domain of the first metal is 5 μm or less in terms of the equivalent circle diameter.

6. The target according to any one of claims 1 to 3, wherein the density calculated based on the content ratio of the first metal and the second metal is 90% or more and 99% or less, and when the cross-section is mapped by SEM-EDX, the size of the domain of the first metal is 5 μm or less in terms of the equivalent circle diameter.

7. A method for manufacturing a target, comprising a step of sintering a metal powder containing 45 at% or more and 90 at% or less of a first metal, the balance being a second metal and impurities, wherein the content of the impurities is 500 mass ppm or less, and the oxygen as the impurities is 200 mass ppm or less.

8. The method for manufacturing a target according to claim 7, containing 45 at% or more and 60 at% or less of the first metal.

9. The method for manufacturing a target according to claim 7 or 8, wherein the metal powder is an alloy powder of the first metal and the second metal.

10. The method for manufacturing a target according to any one of claims 7 to 9, wherein the metal powder has a volume average diameter of 20 μm or more and 120 μm or less.

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