Capacitor and method for manufacturing capacitor

Abstract

The purpose of the present invention is to provide a capacitor capable of increasing capacity. This capacitor (1) is provided with a first conductive member (2), a dielectric layer (4), a second conductive member (5), and an intermediate layer (3). The first conductive member (2) includes a first metal. The dielectric layer (4) overlaps the first conductive member (2). The second conductive member (5) overlaps the dielectric layer (4). The intermediate layer (3) is positioned between the first conductive member (2) and the dielectric layer (4). The intermediate layer (3) contains a metal oxide which is an oxide of the first metal, and a metal compound which is a compound of a second metal different from the first metal.

Description

Capacitor and method of manufacturing the capacitor

[0001] The present disclosure relates to capacitors and methods of manufacturing capacitors, and more particularly to capacitors having dielectric layers and methods of manufacturing capacitors having dielectric layers.

[0002] Patent Document 1 discloses a capacitor including a lower electrode (first conductive member), a dielectric layer formed on the lower electrode, an interface layer formed between the lower electrode and the dielectric layer, and an upper electrode (second conductive member) formed on the dielectric layer.

[0003] In the capacitor disclosed in Patent Document 1, the interfacial layer is formed by surface oxidation of the lower electrode during a high-temperature process in the process of forming a dielectric layer on the lower electrode. The interfacial layer is difficult to function as an electrode, and does not form a high-quality dielectric film, causing a deterioration in capacitor characteristics. In the capacitor disclosed in Patent Document 1, the lower electrode contains a metal nitride.

[0004] In capacitors, it is desirable to increase the capacitance.

[0005] JP 2023-89286 A

[0006] An object of the present disclosure is to provide a capacitor capable of increasing capacitance and a method for manufacturing the capacitor.

[0007] A capacitor according to one aspect of the present disclosure includes a first conductive member, a dielectric layer, a second conductive member, and an intermediate layer. The first conductive member includes a first metal. The dielectric layer overlies the first conductive member. The second conductive member overlies the dielectric layer. The intermediate layer is located between the first conductive member and the dielectric layer. The intermediate layer includes a metal oxide that is an oxide of the first metal and a metal compound that is a compound of a second metal different from the first metal.

[0008] A method for manufacturing a capacitor according to one aspect of the present disclosure is a method for manufacturing a capacitor including a first conductive member, a dielectric layer, a second conductive member, and an intermediate layer. The first conductive member includes a first metal. The dielectric layer overlies the first conductive member. The second conductive member overlies the dielectric layer. The intermediate layer is located between the first conductive member and the dielectric layer. The intermediate layer includes a metal oxide that is an oxide of the first metal and a metal compound that is a compound of a second metal different from the first metal. The method for manufacturing a capacitor includes preparing the first conductive member, forming a reaction layer that includes a compound of the second metal on a native oxide film that includes an oxide of the first metal formed on the first conductive member, forming a dielectric layer on the reaction layer, reacting the native oxide film and the reaction layer by heat treatment to form the intermediate layer, and forming the second conductive member on the dielectric layer.

[0009] A capacitor according to another aspect of the present disclosure includes a first conductive member, a dielectric layer, a second conductive member, and an intermediate layer. The dielectric layer overlies the first conductive member. The second conductive member includes a first metal. The second conductive member overlies the dielectric layer. The intermediate layer is located between the dielectric layer and the second conductive member. The intermediate layer includes a metal oxide that is an oxide of the first metal and a metal compound that is a compound of a second metal different from the first metal.

[0010] FIG. 1 is a schematic cross-sectional view of a capacitor according to a first embodiment. FIGS. 2A to 2E are cross-sectional views illustrating steps in a method for manufacturing the capacitor. FIG. 3 is a graph showing the relationship between the thickness of a dielectric layer and the capacitance equivalent film thickness. FIG. 4 is a graph showing the relationship between the ratio of the number of atoms of the second metal to the total number of atoms of the first metal and the second metal in the intermediate layer and the capacitance of the capacitor. FIG. 5A is a partially cutaway cross-sectional view of a capacitor according to a second embodiment. FIG. 5B is an enlarged view of a main portion B1 of FIG. 5A. FIG. 6 is a schematic cross-sectional view of a capacitor according to a third embodiment. FIGS. 7A to 7F are cross-sectional views illustrating steps in a method for manufacturing the capacitor. FIG. 8 is a schematic cross-sectional view of a capacitor according to a fourth embodiment. FIGS. 9A to 9D are cross-sectional views illustrating steps in a method for manufacturing the capacitor.

[0011] Hereinafter, embodiments 1 to 4 will be described with reference to the drawings. The drawings referred to in the following embodiments 1 to 4 are schematic diagrams, and the sizes and thicknesses of the components in the drawings do not necessarily reflect the actual dimensions, and the size ratios and thickness ratios between the components do not necessarily reflect the actual dimensional ratios.

[0012] (First Embodiment) (1) Capacitor Hereinafter, the configuration of a capacitor 1 according to a first embodiment will be described with reference to the drawings.

[0013] As shown in Fig. 1, the capacitor 1 according to the first embodiment includes a first conductive member 2, a dielectric layer 4, a second conductive member 5, and an intermediate layer 3. The first conductive member 2 includes a first metal. The dielectric layer 4 overlaps the first conductive member 2. The second conductive member 5 overlaps the dielectric layer 4. The intermediate layer 3 is located between the first conductive member 2 and the dielectric layer 4. The intermediate layer 3 includes a metal oxide that is an oxide of the first metal and a metal compound that is a compound of a second metal different from the first metal.

[0014] The capacitor 1 according to the first embodiment can increase the capacitance.

[0015] In this embodiment, a first laminate of the first conductive member 2 and the intermediate layer 3 constitutes a first electrode E1 of the capacitor 1, and a second conductive member 5 constitutes a second electrode E2 of the capacitor 1. That is, the capacitor 1 includes the first electrode E1, a second electrode E2, and a dielectric layer 4 interposed between the first electrode E1 and the second electrode E2. Note that in this embodiment, the first conductive member 2 functions as a support member that supports a second laminate of the intermediate layer 3, the dielectric layer 4, and the second conductive member 5. In this embodiment, the first conductive member 2, the intermediate layer 3, the dielectric layer 4, and the second conductive member 5 are arranged in this order: first conductive member 2, intermediate layer 3, dielectric layer 4, and second conductive member 5.

[0016] (2) Components of the Capacitor Each component of the capacitor 1 according to the first embodiment will be described below with reference to FIG.

[0017] (2.1) First Conductive Member The first conductive member 2 is, for example, a substrate having conductivity. The material of the first conductive member 2 contains a first metal as a main component. The first metal is preferably one metal selected from the group consisting of Al, Ta, Si, Nb, and Ni. The first conductive member 2 is a metal plate, but is not limited to a metal plate and may be, for example, a metal foil. For example, when the first metal is Al, the first conductive member 2 is, for example, an Al substrate, but is not limited to an Al substrate and may be, for example, an Al foil.

[0018] 1 , the first conductive member 2 has a first main surface 21 and a second main surface 22 opposite to the first main surface 21. When viewed in a plan view from the thickness direction D1 of the first conductive member 2, the outer edge of the first conductive member 2 has a rectangular shape.

[0019] The thickness of the first conductive member 2 is, for example, not less than 100 μm and not more than 1 mm.

[0020] (2.2) Dielectric Layer The dielectric layer 4 overlaps the first main surface 21 of the first conductive member 2. The dielectric layer 4 has a first main surface 41 on the second conductive member 5 side and a second main surface 42 opposite the first main surface 41. In the dielectric layer 4, the second main surface 42 of the dielectric layer 4 faces the first main surface 21 of the first conductive member 2. The dielectric layer 4 is located on the main surface 31 of the intermediate layer 3 opposite the first conductive member 2 side.

[0021] The dielectric layer 4 covers the entire first main surface 21 of the first conductive member 2 via the intermediate layer 3, but it is sufficient that it covers at least a portion of the first main surface 21 of the first conductive member 2.

[0022] The dielectric material of the dielectric layer 4 preferably has a higher dielectric constant than an oxide of Si. From the viewpoint of increasing the capacitance of the capacitor 1, the dielectric constant of the dielectric material of the dielectric layer 4 is preferably higher than the dielectric constant of the metal oxide of the first metal. The dielectric layer 4 preferably contains an oxide of a metal selected from the group consisting of Zr, Ta, Hf, Nb, and La. More specifically, the material of the dielectric layer 4 is ZrO ２ , Ta ２ O ５ , HfO ２ , Nb ２ O ５ and La ２ O ５ It is preferable that either of the above is used.

[0023] From the viewpoint of reducing the leakage current of the capacitor 1, the thickness of the dielectric layer 4 is preferably 3 nm or more, and more preferably 5 nm or more. From the viewpoint of increasing the capacitance of the capacitor 1, the thickness of the dielectric layer 4 is preferably 100 nm or less, more preferably 50 nm or less, and even more preferably 20 nm or less.

[0024] (2.3) Second Conductive Member The second conductive member 5 overlaps the dielectric layer 4. In this embodiment, the second conductive member 5 contacts the first main surface 41 of the dielectric layer 4. The second conductive member 5 is formed directly on the first main surface 41 of the dielectric layer 4.

[0025] The material of the second conductive member 5 is, for example, Al, Cu, Zn, TiN, MoN, CoN, TaN, or RuO. ２ , IrO ２ , and conductive polymers.

[0026] The thickness of the second conductive member 5 is, for example, not less than 50 nm and not more than 1 mm.

[0027] (2.4) Intermediate Layer The intermediate layer 3 is located between the first conductive member 2 and the dielectric layer 4. In the capacitor 1 of this embodiment, the intermediate layer 3 is in contact with both the first conductive member 2 and the dielectric layer 4. That is, the capacitor 1 of this embodiment has an interface between the intermediate layer 3 and the first conductive member 2, and an interface between the intermediate layer 3 and the dielectric layer 4. The intermediate layer 3 contains a metal oxide that is an oxide of a first metal, and a metal compound that is a compound of a second metal different from the first metal. In the intermediate layer 3, the metal oxide and the metal compound are mixed.

[0028] From the viewpoint of improving the conductivity of the intermediate layer 3, the band gap of the metal compound is preferably smaller than the band gap of the metal oxide in the intermediate layer 3. The band gap is a value measured by STEM (Scanning Transmission Electron Microscope)-EELS (Electron Energy Loss Spectroscopy). The band gap may also be a value measured by STM (Scanning Tunneling Microscope).

[0029] From the viewpoint of improving the conductivity of the intermediate layer 3, the metal compound in the intermediate layer 3 is preferably an oxide of the second metal or a nitride of the second metal. In the capacitor 1, by improving the conductivity of the intermediate layer 3, the ESR (Equivalent Series Resistance) of the capacitor 1 can be reduced.

[0030] As described above, the first metal is preferably one metal selected from the group consisting of Al, Ta, Si, Nb, and Ni. Therefore, the metal oxide, which is an oxide of the first metal, is, for example, Al ２ O ３ , Ta２ O ５ , SiO ２ , Nb ２ O ５ Alternatively, NiO is preferred.

[0031] The second metal is preferably one metal selected from the group consisting of Ti, Cu, Zn, Ga, In, and Sn. The oxide of the second metal is preferably TiO ２ , CuO ２ , ZnO, Ga ２ O ３ , In ２ O ３ or SnO ２ The nitride of the second metal is preferably TiN, CuN, Zn ３ N ２ , GaN, InN or Sn ３ N ４ It is preferable that:

[0032] From the viewpoint of increasing the capacitance of capacitor 1, the ratio of the number of atoms of the second metal to the total number of atoms of the first metal and the second metal in intermediate layer 3 is preferably 11 atom % or more. The above ratio is a value obtained by analysis using STEM (Scanning Transmission Electron Microscope)-EDX (Energy Dispersive X-ray Spectroscopy).

[0033] (3) Method for Manufacturing Capacitor A method for manufacturing the capacitor 1 will be briefly described with reference to FIGS. 2A to 2E.

[0034] The method for manufacturing the capacitor 1 includes a first step, a second step, a third step, a fourth step, and a fifth step.

[0035] In the first step, as shown in FIG. 2A , a first conductive member 2 having a first main surface 21 and a second main surface 22 is prepared. The first conductive member 2 is, for example, an Al substrate with a thickness of 150 μm. A natural oxide film 23 is formed on the first main surface 21 of the first conductive member 2 prepared in the first step. When the first metal of the first conductive member 2 is Al, the material of the natural oxide film 23 (oxide of the first metal) is Al. ２ O ３The thickness of the native oxide film 23 is, for example, 3 nm or more and 5 nm or less. In the method for manufacturing the capacitor 1, the native oxide film 23 may be formed in the first step. That is, in the first step, for example, after preparing the first conductive member 2, the native oxide film 23 may be formed by leaving the first conductive member 2 in the atmosphere for a predetermined period of time or more.

[0036] In the second step, as shown in FIG. 2B, a reaction layer 33 is formed on the native oxide film 23. The reaction layer 33 is a layer that reacts with the native oxide film 23 after the second step. The material of the reaction layer 33 includes the material of the metal compound of the second metal out of the oxide of the first metal and the metal compound of the second metal in the intermediate layer 3. When the oxide of the first metal in the intermediate layer 3 is Al, the reaction layer 33 is formed of Al. ２ O ３ When the metal compound of the second metal is TiN, the material of the reaction layer 33 is TiN. In the second step, the reaction layer 33 is formed on the native oxide film 23 by, for example, ALD (Atomic Layer Deposition).

[0037] 2C, for example, the dielectric layer 4 is formed on the reaction layer 33. In the third step, the dielectric layer 4 is formed on the reaction layer 33 by, for example, the ALD method.

[0038] In the fourth step, a heat treatment is performed to cause the native oxide film 23 and the reaction layer 33 to react with each other, thereby forming an intermediate layer 3 on the first conductive member 2, as shown in FIG. 2D . More specifically, in the fourth step, a heat treatment is performed to cause the material of the native oxide film 23 and the material of the reaction layer 33 to interdiffuse, thereby forming the intermediate layer 3 on the first conductive member 2. In short, in the method for manufacturing the capacitor 1, the intermediate layer 3 is formed by utilizing the native oxide film 23 and the reaction layer 33.

[0039] 2E, the capacitor 1 is obtained by forming a second conductive member 5 on the dielectric layer 4. In the fifth step, the second conductive member 5 is formed on the dielectric layer 4 by, for example, evaporation, CVD (Chemical Vapor Deposition), sputtering, or ALD.

[0040] The method for manufacturing the capacitor 1 is not limited to the above example. For example, if interdiffusion occurs between the dielectric layer 4 and the reaction layer 33 during heat treatment, the reaction layer 33 may be formed on the native oxide film 23, and then heat treatment may be performed before forming the dielectric layer 4 to form the intermediate layer 3, and then the dielectric layer 4 may be formed on the intermediate layer 3.

[0041] (4) Examples The structural parameters of the capacitors 1 of Examples 1 to 3 are shown in Table 1 below. The capacitors 1 of Examples 1 to 3 have the same structural parameters except for the thickness of the dielectric layer 4, which is different from each other. The molar ratio of the intermediate layer 3 is the molar ratio of the metal oxide, which is an oxide of the first metal, to the metal compound, which is a compound of the second metal.

[0042]

[0043] Table 2 below shows the capacitance, withstand voltage, ratio of the number of atoms of the second metal to the total number of atoms of the first metal and the second metal in the intermediate layer 3 (hereinafter sometimes abbreviated as the ratio of the second metal), and band gap of the intermediate layer 3 of the capacitors 1 of Examples 1 to 3. The withstand voltage is measured when the current density is 1×10 when the voltage applied between the first electrode E1 and the second electrode E2 is swept. －７ A / cm ２ is the voltage value reached.

[0044]

[0045] The structural parameters of capacitors 1 of Examples 4 to 14 are shown in Table 3 below. Examples 4 to 14 differ from each other in the material of intermediate layer 3, but the structural parameters other than the material of intermediate layer 3 are the same as those of Example 1.

[0046]

[0047] The capacitance, withstand voltage, proportion of the second metal in the intermediate layer 3, and band gap of the intermediate layer 3 of the capacitors 1 of Examples 4 to 14 are shown in Table 4 below.

[0048]

[0049] The structural parameters of the capacitors 1 of Examples 15 to 19 are shown in Table 5 below. Examples 15 to 19 differ from Example 1 in the type of metal compound in the intermediate layer 3. In addition, Examples 15 to 19 differ from each other in the material of the dielectric layer 4, which is also different from the material of the dielectric layer 4 of Example 1.

[0050]

[0051] Table 6 below shows the capacitance, withstand voltage, ratio of the number of atoms of the second metal to the total number of atoms of the first metal and the second metal in the intermediate layer 3 (hereinafter sometimes abbreviated as the ratio of the second metal), and band gap of the intermediate layer for the capacitors 1 of Examples 15 to 19.

[0052]

[0053] The structural parameters of the capacitors 1 of Examples 20 to 23 are shown in Table 7 below. Examples 20 to 23 differ from Example 1 in the material of the first conductive member 2 and the material of the metal oxide of the intermediate layer 3.

[0054]

[0055] The capacitance, withstand voltage, ratio of the number of atoms of the second metal to the total number of atoms of the first metal and the second metal in the intermediate layer 3 (hereinafter sometimes abbreviated as the ratio of the second metal), and band gap of the intermediate layer 3 of the capacitors 1 of Examples 20 to 23 are shown in Table 8 below.

[0056]

[0057] The structural parameters of the capacitors 1 of Examples 24 to 27 are shown in Table 9 below. Examples 24 to 27 differ from one another in the molar ratio of metal oxide to metal compound in the intermediate layer 3.

[0058]

[0059] Table 10 below shows the capacitance, withstand voltage, ratio of the number of atoms of the second metal to the total number of atoms of the first metal and the second metal in the intermediate layer 3 (hereinafter sometimes abbreviated as the ratio of the second metal), and band gap of the intermediate layer 3 of the capacitors 1 of Examples 24 to 27.

[0060]

[0061] The structural parameters of the capacitors of Comparative Examples 1 to 3 are shown in Table 11 below. The capacitors of Comparative Examples 1 to 3 differ from the capacitors 1 of Examples 1 to 3 in that they have a native oxide film instead of the intermediate layer 3.

[0062]

[0063] The capacitance, withstand voltage, proportion of the second metal, and band gap of the native oxide film of the capacitors of Comparative Examples 1 to 3 are shown in Table 12 below.

[0064]

[0065] (5) Other Capacitor Characteristics (5.1) Capacitive Equivalent Film Thickness The capacitive equivalent film thickness is a value calculated by the equation: capacitive equivalent film thickness = ε × S / C. Here, "ε" is the dielectric constant of the dielectric layer 4. Also, "C" is the electrostatic capacitance of the capacitor 1. Also, S is the electrode area of ​​the capacitor 1, more specifically, the area of ​​the surface of the second conductive member 5 facing the first conductive member 2. In each of Examples 1 to 22, the first laminate of the first conductive member 2 and the intermediate layer 3 constitutes the first electrode E1 of the capacitor 1, and the second conductive member 5 constitutes the second electrode E2 of the capacitor 1. In each of Comparative Examples 1 to 3, the first conductive member constitutes the first electrode of the capacitor, and the second conductive member constitutes the second electrode of the capacitor.

[0066] 3 is a graph showing the relationship between the thickness of the dielectric layer 4 and the capacitance equivalent film thickness. In FIG. 3, the capacitance equivalent film thickness of each of the capacitors 1 in Examples 1, 2, and 3 is shown by a white circle, and the capacitance equivalent film thickness of each of the capacitors in Comparative Examples 1, 2, and 3 is shown by a black circle. The thickness of the dielectric layer 4 of each of the capacitors 1 in Examples 1, 2, and 3 is the same as the thickness of the dielectric layer of each of the capacitors in Comparative Examples 1, 2, and 3, respectively.

[0067] 3 shows that the capacitance equivalent film thickness can be reduced in Examples 1, 2, and 3 compared to Comparative Examples 1, 2, and 3, respectively. Therefore, the capacitance of the capacitors 1 of Examples 1, 2, and 3 can be increased compared to the capacitance of the capacitors of Comparative Examples 1, 2, and 3, respectively.

[0068] (5.2) Capacitance FIG. 4 is a graph showing the relationship between the capacitance and the ratio of the number of atoms of the second metal to the total number of atoms of the first metal and the second metal in the intermediate layer 3. FIG. 4 also shows the capacitance of each of Comparative Example 1, Example 1, and Examples 24 to 27. Note that in Example 1 and Examples 24 to 27, the material and thickness of the first conductive member 2, the material and thickness of the dielectric layer 4, the material and thickness of the second conductive member 5, and the material and thickness of the intermediate layer 3 are the same, but the ratio of the number of atoms of the second metal to the total number of atoms of the first metal and the second metal in the intermediate layer 3 is different. Furthermore, in Comparative Example 1, the material and thickness of the first conductive member, the material and thickness of the dielectric layer, and the material and thickness of the second conductive member are the same as those of Example 1 and Examples 24 to 27, respectively.

[0069] From Figure 4, it can be seen that when the ratio of the number of atoms of the second metal to the total number of atoms of the first metal and the second metal in the intermediate layer 3 is 11 atom% or more, the capacitance of the capacitor 1 can be made larger than in Comparative Example 1, where the ratio is 0 atom%.

[0070] (6) Advantages The capacitor 1 according to the first embodiment includes an intermediate layer 3 located between the first conductive member 2 and the dielectric layer 4. The intermediate layer 3 includes a metal oxide that is an oxide of a first metal and a metal compound that is a compound of a second metal different from the first metal.

[0071] The above configuration allows for an increase in the capacitance of the capacitor 1. More specifically, the capacitor 1 according to the first embodiment includes the intermediate layer 3 containing a metal oxide that is an oxide of a first metal and a metal compound that is a compound of a second metal different from the first metal. This allows for an increase in capacitance compared to when an oxide film of the first metal (e.g., a native oxide film) is interposed between the first conductive member and the dielectric layer. Furthermore, the above configuration can suppress variations in capacitance due to variations in the thickness of the oxide film of the first metal (e.g., a native oxide film), thereby reducing variations in the capacitance of the capacitor 1.

[0072] In addition, the manufacturing method of capacitor 1 according to embodiment 1 includes preparing a first conductive member 2, forming a reaction layer 33 containing a compound of a second metal on a natural oxide film 23 containing an oxide of a first metal formed on first conductive member 2, forming a dielectric layer 4 on reaction layer 33, reacting natural oxide film 23 with reaction layer 33 by heat treatment to form intermediate layer 3, and forming a second conductive member 5 on dielectric layer 4.

[0073] The above configuration allows for an increase in the capacitance of the capacitor 1. More specifically, the method for manufacturing the capacitor 1 according to the first embodiment forms the intermediate layer 3 containing a metal oxide, which is an oxide of a first metal, and a metal compound, which is a compound of a second metal different from the first metal. This allows for an increase in capacitance compared to when a native oxide film, which is an oxide film of the first metal, is interposed between the first conductive member and the dielectric layer. Furthermore, the above configuration can suppress variations in capacitance due to variations in the thickness of the oxide film of the first metal (e.g., a native oxide film), thereby reducing variations in the capacitance of the capacitor 1.

[0074] 5A and 5B, a capacitor 1A according to a second embodiment will be described. In the capacitor 1A according to the second embodiment, the same components as those of the capacitor 1 according to the first embodiment (see FIG. 1) are denoted by the same reference numerals, and the description thereof will be omitted.

[0075] (1) Configuration As shown in FIGS. 5A and 5B, capacitor 1A includes a first conductive member 2, an intermediate layer 3, a dielectric layer 4, and a second conductive member 5, similar to capacitor 1.

[0076] In capacitor 1A, first conductive member 2 is a metal foil (e.g., Al foil). In capacitor 1A, the portion of first conductive member 2 on the first main surface 21 side is made porous, and first conductive member 2 includes porous portion 24 having a plurality of pores 25. In capacitor 1A, first main surface 21 of first conductive member 2 includes surface 241 of porous portion 24.

[0077] In capacitor 1A, intermediate layer 3 and dielectric layer 4 have shapes that conform to surface 241 of porous portion 24. Second conductive member 5 includes a plurality of first portions 51 located in a plurality of holes 25 of porous portion 24, and a second portion 52 to which the plurality of first portions 51 are connected.

[0078] (2) Advantages The capacitor 1A of embodiment 2, like the capacitor 1 of embodiment 1, has an intermediate layer 3 located between the first conductive member 2 and the dielectric layer 4, which makes it possible to increase the capacitance.

[0079] Furthermore, in the capacitor 1A according to the second embodiment, the first conductive member 2 has the porous portion 24, and therefore the capacitance can be made larger than that of the capacitor 1 according to the first embodiment.

[0080] (Embodiment 3) A capacitor 1B according to embodiment 3 will be described with reference to Fig. 6. Regarding the capacitor 1B according to embodiment 3, components similar to those of the capacitor 1 according to embodiment 1 (see Fig. 1) are denoted by the same reference numerals and descriptions thereof will be omitted.

[0081] (1) Configuration As shown in FIG. 6 , the capacitor 1B of the third embodiment differs from the capacitor 1 of the first embodiment in that it further includes a second intermediate layer 6 that is different from the first intermediate layer 3 .

[0082] The second intermediate layer 6 is located between the dielectric layer 4 and the second conductive member 5. In the capacitor 1B of this embodiment, the second intermediate layer 6 is in contact with both the dielectric layer 4 and the second conductive member 5. In other words, the capacitor 1B of this embodiment has an interface between the second intermediate layer 6 and the dielectric layer 4, and an interface between the second intermediate layer 6 and the second conductive member 5.

[0083] The first conductive member 2 includes a first metal. The first intermediate layer 3 includes a metal oxide that is an oxide of the first metal and a metal compound that is a compound of a second metal different from the first metal. The second conductive member 5 includes a third metal. The second intermediate layer 6 includes a metal oxide that is an oxide of the third metal and a metal compound that is a compound of a fourth metal different from the third metal. In this embodiment, the first conductive member 2 and the first intermediate layer 3 form a first electrode E1 of the capacitor 1B, and the second conductive member 5 and the second intermediate layer 6 form a second electrode E2 of the capacitor 1B.

[0084] From the viewpoint of improving the conductivity of the second intermediate layer 6, the band gap of the metal compound is preferably smaller than the band gap of the metal oxide in the second intermediate layer 6. The band gap is a value measured by STEM-EELS.

[0085] From the viewpoint of improving the conductivity of the second intermediate layer 6, the metal compound in the second intermediate layer 6 is preferably an oxide of a fourth metal or a nitride of a fourth metal.

[0086] The third metal is preferably one metal selected from the group consisting of Al, Ta, Si, Nb, and Ni. Therefore, the metal oxide of the third metal is, for example, Al ２ O ３ , Ta ２ O ５ , SiO ２ , Nb ２ O ５ Alternatively, NiO is preferred.

[0087] The fourth metal is preferably one metal selected from the group consisting of Ti, Cu, Zn, Ga, In, and Sn. The oxide of the fourth metal is preferably TiO ２ , CuO ２ , ZnO, Ga ２ O３ , In ２ O ３ or SnO ２ The nitride of the fourth metal is preferably TiN, CuN, Zn ３ N ２ , GaN, InN or Sn ３ N ４ It is preferable that:

[0088] From the viewpoint of increasing the capacitance of capacitor 1B, the ratio of the number of atoms of the fourth metal to the total number of atoms of the third metal and the fourth metal in second intermediate layer 6 is preferably 11 atom % or more. This ratio is a value measured by STEM-EELS.

[0089] (2) Manufacturing Method of Capacitor A manufacturing method of the capacitor 1B will be briefly described with reference to Figures 7A to 7F. Note that the description of the same steps as those in the manufacturing method of the capacitor 1 according to the first embodiment will be omitted as appropriate.

[0090] The method for manufacturing the capacitor 1B includes a first step, a second step, a third step, a fourth step, a fifth step, and a sixth step.

[0091] 7A , a first conductive member 2 having a first main surface 21 and a second main surface 22 is prepared. The first conductive member 2 is, for example, an Al substrate with a thickness of 150 μm. A native oxide film 23 is formed on the first main surface 21 of the first conductive member 2 prepared in the first step.

[0092] 7B, in the second step, a reaction layer 33 (hereinafter also referred to as a first reaction layer 33) is formed on the native oxide film 23. The oxide of the first metal in the first intermediate layer 3 is Al. ２ O ３ and when the metal compound of the second metal is TiN, the material of the first reaction layer 33 is TiN.

[0093] In the third step, as shown in FIG. 7C, for example, a dielectric layer 4 is formed on the first reaction layer 33.

[0094] In the fourth step, a heat treatment is performed to cause the native oxide film 23 and the first reaction layer 33 to react with each other, thereby forming a first intermediate layer 3 on the first conductive member 2, as shown in FIG. 7D.

[0095] In the fifth step, as shown in FIG. 7E , a second reaction layer 63 is formed on the dielectric layer 4. In the fifth step, the second reaction layer 63 is formed by, for example, an ALD method. The material of the second reaction layer 63 includes a material of the metal compound of the fourth metal out of the oxide of the third metal and the metal compound of the fourth metal in the second intermediate layer 6. For example, if the oxide of the third metal in the second intermediate layer 6 is Al ２ O ３ and when the metal compound of the fourth metal is TiN, the material of the second reaction layer 63 is TiN.

[0096] In the sixth step, the second conductive member 5 is formed by, for example, a vapor deposition method. In the sixth step, oxygen taken into the second reaction layer 63 during the formation of the second conductive member 5 combines with the third metal of the second conductive member 5 to form a metal oxide, and a second intermediate layer 6 is formed between the dielectric layer 4 and the second conductive member 5, as shown in FIG. 7F . In the manufacturing method of this embodiment, the second reaction layer 63 functions as a protective layer that suppresses deterioration of the dielectric layer 4 that may occur during the formation of the second conductive member 5 in the sixth step.

[0097] (3) Example The structural parameters of the capacitor 1B of the example are shown in Table 13 below.

[0098]

[0099] Below, the capacitance, withstand voltage, ratio of the number of atoms of the second metal to the total number of atoms of the first metal and the second metal in each of the first intermediate layer 3 and the second intermediate layer 6 (hereinafter sometimes abbreviated as the ratio of the second metal), and band gap of each of the first intermediate layer 3 and the second intermediate layer 6 are shown in Table 14 below.

[0100]

[0101] (4) Advantages Like the capacitor 1 according to the first embodiment, the capacitor 1B according to the third embodiment allows the capacitance to be increased.

[0102] Fourth Embodiment (1) Capacitor The configuration of a capacitor 1C according to a fourth embodiment will be described below with reference to the drawings.

[0103] 8 , the capacitor 1C according to the fourth embodiment includes a first conductive member 2, a dielectric layer 4, a second conductive member 5, and an intermediate layer 7. The first conductive member 2 includes a first metal. The dielectric layer 4 overlaps the first conductive member 2. The second conductive member 5 overlaps the dielectric layer 4. The intermediate layer 7 is located between the second conductive member 5 and the dielectric layer 4. The second conductive member 5 is thinner than the first conductive member 2. The intermediate layer 7 includes a metal oxide that is an oxide of the first metal and a metal compound that is a compound of a second metal different from the first metal.

[0104] According to the capacitor 1C of the fourth embodiment, it is possible to increase the capacitance.

[0105] In this embodiment, the first conductive member 2 constitutes the first electrode E1 of the capacitor 1C, and a laminate of the intermediate layer 7 and the second conductive member 5 constitutes the second electrode E2 of the capacitor 1C. That is, the capacitor 1C includes the first electrode E1, the second electrode E2, and the dielectric layer 4 interposed between the first electrode E1 and the second electrode E2. Note that in this embodiment, the first conductive member 2 functions as a support member that supports the second laminate of the dielectric layer 4, the intermediate layer 7, and the second conductive member 5. In this embodiment, the first conductive member 2, the dielectric layer 4, the intermediate layer 7, and the second conductive member 5 are arranged in this order: first conductive member 2, dielectric layer 4, intermediate layer 7, and second conductive member 5.

[0106] (2) Components of the Capacitor Hereinafter, each component of the capacitor 1C according to the fourth embodiment will be described with reference to FIG.

[0107] (2.1) First Conductive Member The first conductive member 2 is, for example, a substrate having conductivity. The material of the first conductive member 2 is preferably, for example, one type of metal selected from the group consisting of Al, Ta, Si, Nb, and Ni. The first conductive member 2 is a metal plate, but is not limited to a metal plate and may be, for example, a metal foil. The first conductive member 2 is, for example, an Al substrate, but is not limited to an Al substrate and may be, for example, an Al foil.

[0108] 8, the first conductive member 2 has a first main surface 21 and a second main surface 22 opposite to the first main surface 21. When viewed in a plan view from the thickness direction D1 of the first conductive member 2, the outer edge of the first conductive member 2 has a rectangular shape.

[0109] The thickness of the first conductive member 2 is, for example, not less than 100 μm and not more than 1 mm.

[0110] (2.2) Dielectric Layer The dielectric layer 4 overlaps the first main surface 21 of the first conductive member 2. The dielectric layer 4 has a first main surface 41 on the second conductive member 5 side and a second main surface 42 opposite to the first main surface 41. In the dielectric layer 4, the second main surface 42 of the dielectric layer 4 contacts the first main surface 21 of the first conductive member 2.

[0111] The dielectric layer 4 covers the entire first main surface 21 of the first conductive member 2 , but it is sufficient that the dielectric layer 4 covers at least a part of the first main surface 21 of the first conductive member 2 .

[0112] The material of the dielectric layer 4 preferably has a higher dielectric constant than an oxide of Si. From the viewpoint of increasing the capacitance of the capacitor 1C, the dielectric constant of the dielectric material of the dielectric layer 4 is preferably higher than the dielectric constant of the metal oxide of the first metal. The dielectric layer 4 preferably contains an oxide of a metal selected from the group consisting of Zr, Ta, Hf, Nb, and La. More specifically, the material of the dielectric layer 4 is ZrO ２ , Ta ２ O ５ , HfO ２ , Nb ２ O ５ and La ２ O ５ It is preferable that either of the above is used.

[0113] From the viewpoint of reducing the leakage current of the capacitor 1C, the thickness of the dielectric layer 4 is preferably 3 nm or more, and more preferably 5 nm or more. From the viewpoint of increasing the capacitance of the capacitor 1C, the thickness of the dielectric layer 4 is preferably 100 nm or less, more preferably 50 nm or less, and even more preferably 30 nm or less.

[0114] (2.3) Second Conductive Member The second conductive member 5 overlaps the dielectric layer 4. In this embodiment, the second conductive member 5 faces the first main surface 41 of the dielectric layer 4. The second conductive member 5 is formed on the first main surface 41 of the dielectric layer 4 with the intermediate layer 7 interposed therebetween.

[0115] The material of the second conductive member 5 contains a first metal as a main component, and the first metal is preferably one metal selected from the group consisting of Al, Ta, Si, Nb, and Ni.

[0116] The thickness of the second conductive member 5 is, for example, not less than 50 nm and not more than 10 μm.

[0117] (2.4) Intermediate Layer The intermediate layer 7 is located between the second conductive member 5 and the dielectric layer 4. In the capacitor 1C of this embodiment, the intermediate layer 7 is in contact with both the second conductive member 5 and the dielectric layer 4. That is, the capacitor 1C of this embodiment has an interface between the intermediate layer 7 and the second conductive member 5, and an interface between the intermediate layer 7 and the dielectric layer 4. The intermediate layer 7 contains a metal oxide that is an oxide of a first metal, and a metal compound that is a compound of a second metal different from the first metal. In the intermediate layer 7, the metal oxide and the metal compound are mixed.

[0118] From the viewpoint of improving the conductivity of the intermediate layer 7, the band gap of the metal compound is preferably smaller than the band gap of the metal oxide in the intermediate layer 7. The band gap is a value measured by STEM-EELS.

[0119] From the viewpoint of improving the conductivity of the intermediate layer 7, the metal compound in the intermediate layer 7 is preferably an oxide of the second metal or a nitride of the second metal.

[0120] As described above, the first metal is preferably one metal selected from the group consisting of Al, Ta, Si, Nb, and Ni. Therefore, the metal oxide, which is an oxide of the first metal, is, for example, Al ２ O ３ , Ta ２ O ５ , SiO ２ , Nb ２ O ５ Alternatively, NiO is preferred.

[0121] The second metal is preferably one metal selected from the group consisting of Ti, Cu, Zn, Ga, In, and Sn. The oxide of the second metal is preferably TiO ２ , CuO ２ , ZnO, Ga ２ O ３ , In ２ O ３ or SnO ２ The nitride of the second metal is preferably TiN, CuN, Zn ３ N ２ , GaN, InN or Sn ３ N ４ It is preferable that:

[0122] From the viewpoint of increasing the capacitance of the capacitor 1C, the ratio of the number of atoms of the second metal to the total number of atoms of the first metal and the second metal in the intermediate layer 7 is preferably 11 atom % or more. The above ratio is a value obtained by STEM-EDX analysis.

[0123] (3) Method for Manufacturing Capacitor A method for manufacturing the capacitor 1C will be briefly described with reference to FIGS. 9A to 9D.

[0124] The method for manufacturing the capacitor 1C includes a first step, a second step, a third step, and a fourth step.

[0125] 9A, a first conductive member 2 having a first main surface 21 and a second main surface 22 is prepared. The first conductive member 2 is, for example, an Al substrate with a thickness of 150 μm.

[0126] 9B , in the second step, the dielectric layer 4 is formed on the first main surface 21 of the first conductive member 2. In the second step, for example, the native oxide film on the first main surface 21 of the first conductive member 2 is removed, and then the dielectric layer 4 is formed directly on the first main surface 21 of the first conductive member 2 by the ALD method.

[0127] 9C, a reaction layer 73 is formed on the dielectric layer 4. In the third step, the reaction layer 73 is formed by, for example, the ALD method. The material of the reaction layer 73 includes a material of the metal compound of the second metal out of the oxide of the first metal and the metal compound of the second metal in the intermediate layer 7. For example, if the oxide of the first metal in the intermediate layer 7 is Al ２ O ３ When the metal compound of the second metal is TiN, the material of the reaction layer 73 is TiN.

[0128] In the fourth step, the second conductive member 5 is formed by, for example, a vapor deposition method. In the fourth step, oxygen taken into the reaction layer 73 during the formation of the second conductive member 5 combines with the first metal of the second conductive member 5 to form a metal oxide, and an intermediate layer 7 is formed between the dielectric layer 4 and the second conductive member 5, as shown in Fig. 9D. In the manufacturing method of the capacitor 1C of this embodiment, the reaction layer 73 functions as a protective layer that suppresses deterioration of the dielectric layer 4 that may occur during the formation of the second conductive member 5 in the fourth step.

[0129] (4) Example The structural parameters of the capacitor 1C of the example are shown in Table 15. The molar ratio of the intermediate layer 7 is the molar ratio of the metal oxide, which is an oxide of the first metal, to the metal compound, which is a compound of the second metal.

[0130]

[0131] The capacitance, withstand voltage, ratio of the number of atoms of the second metal to the total number of atoms of the first metal and the second metal in the intermediate layer 7 (hereinafter sometimes abbreviated as the ratio of the second metal), and band gap of the intermediate layer 7 of the capacitor 1C of the example are shown in Table 16 below. Note that the withstand voltage is determined when the current density is 1×10 when the voltage applied between the first electrode E1 and the second electrode E2 is swept. －７ A / cm ２is the voltage value reached.

[0132]

[0133] The structural parameters of the comparative capacitor are shown in Table 17 below. The comparative capacitor differs from capacitor 1C of the example in that it includes a metal oxide layer containing a first metal instead of intermediate layer 7.

[0134]

[0135] The capacitance, withstand voltage, proportion of the second metal, and band gap of the metal oxide layer of the comparative capacitor are shown in Table 18 below.

[0136]

[0137] (5) Advantages The capacitor 1C according to the fourth embodiment includes an intermediate layer 7 located between the second conductive member 5 and the dielectric layer 4. The intermediate layer 7 includes a metal oxide that is an oxide of a first metal and a metal compound that is a compound of a second metal different from the first metal.

[0138] The above configuration allows for an increase in the capacitance of the capacitor 1C. More specifically, the capacitor 1C according to the fourth embodiment includes an intermediate layer 7 containing a metal oxide, which is an oxide of a first metal, and a metal compound, which is a compound of a second metal different from the first metal. This allows for an increase in capacitance compared to a case where an oxide film (metal oxide layer) of the first metal is interposed between the second conductive member and the dielectric layer. Furthermore, the above configuration can suppress variations in capacitance due to variations in the thickness of the oxide film (metal oxide layer) of the first metal, thereby reducing variations in the capacitance of the capacitor 1C.

[0139] (Modifications) The above-described first to fourth embodiments are merely examples of various embodiments of the present disclosure. The above-described first to fourth embodiments can be modified in various ways depending on the design, etc., as long as the object of the present disclosure can be achieved.

[0140] For example, in capacitors 1, 1A, and 1B, the intermediate layer 3 may include a region in which the ratio of the number of atoms of the second metal to the total number of atoms of the first metal and the second metal decreases as one approaches the first conductive member 2 from the main surface 31 of the intermediate layer 3 in the thickness direction of the intermediate layer 3.

[0141] In addition, in capacitors 1 , 1A, and 1B, a metal oxide portion made of the same material as the metal oxide contained in intermediate layer 3 may be interposed between part of intermediate layer 3 and first conductive member 2 .

[0142] Furthermore, capacitors 1, 1A, and 1B are used, for example, at frequencies of 50 Hz to 1 MHz, but when used at frequencies of less than 100 kHz, a metal oxide film (native oxide film) of 1 nm to 2 nm may remain between the first main surface 21 of the first conductive member 2 and the intermediate layer 3.

[0143] Furthermore, in the capacitors 1, 1A, and 1B, a part of the reaction layer 33 may remain between the dielectric layer 4 and the intermediate layer 3. In this case, in the capacitor 1, the first conductive member 2, the intermediate layer 3, and a part of the reaction layer 33 form the first electrode E1.

[0144] Furthermore, in capacitors 1, 1B, and 1C, the outer edge of the first conductive member 2 when viewed in a plane from the thickness direction D1 of the first conductive member 2 is not limited to a rectangular shape and may be any shape, for example, a square shape or a circular shape.

[0145] In addition, in capacitors 1, 1B, and 1C, first conductive member 2 may have porous portion 24, similar to capacitor 1A.

[0146] In the capacitors 1, 1B, and 1C, the first conductive member 2 may be, for example, a porous body containing a valve metal. More specifically, the first conductive member 2 may be a porous sintered body containing tantalum. The material of the first conductive member 2 is not limited to tantalum, and may be, for example, aluminum, niobium, titanium, zirconium, or hafnium.

[0147] When the first conductive member 2 is a porous body, the intermediate layer 3 covers the surface of the porous body that constitutes the first conductive member 2 and has a shape that conforms to the surface of the porous body.

[0148] Furthermore, the capacitors 1, 1B, and 1C may have a plurality of recesses in the first main surface 21 of the first conductive member 2, the depth direction of which is the thickness direction D1 of the first conductive member 2. The plurality of recesses may be formed by, for example, etching. Each of the plurality of recesses includes a trench.

[0149] Furthermore, in capacitors 1, 1B, and 1C, first main surface 21 of first conductive member 2 may be a rough surface.

[0150] (Aspects) The following aspects are disclosed in this specification.

[0151] A capacitor (1; 1A; 1B) according to a first aspect includes a first conductive member (2), a dielectric layer (4), a second conductive member (5), and an intermediate layer (3). The first conductive member (2) includes a first metal. The dielectric layer (4) overlies the first conductive member (2). The second conductive member (5) overlies the dielectric layer (4). The intermediate layer (3) is located between the first conductive member (2) and the dielectric layer (4). The intermediate layer (3) includes a metal oxide that is an oxide of the first metal and a metal compound that is a compound of a second metal different from the first metal.

[0152] According to this aspect, it is possible to increase the capacitance.

[0153] In the capacitor (1; 1A; 1B) according to the second aspect, the band gap of the metal compound is smaller than the band gap of the metal oxide in the first aspect.

[0154] According to this embodiment, the conductivity of the intermediate layer (3) can be improved.

[0155] In the capacitor (1; 1A; 1B) according to the third aspect, in the first or second aspect, the metal compound is an oxide of the second metal or a nitride of the second metal.

[0156] According to this embodiment, the conductivity of the intermediate layer (3) can be improved.

[0157] In the capacitor (1; 1A; 1B) according to the fourth aspect, in any one of the first to third aspects, the dielectric constant of the dielectric material of the dielectric layer (4) is higher than the dielectric constant of the metal oxide.

[0158] According to this embodiment, the capacitance can be made larger than when the dielectric material of the dielectric layer (4) is a metal oxide (oxide of the first metal).

[0159] In a capacitor (1; 1A; 1B) according to a fifth aspect, in any one of the first to fourth aspects, the first metal is one metal selected from the group consisting of Al, Ta, Si, Nb, and Ni, and the second metal is one metal selected from the group consisting of Ti, Cu, Zn, Ga, In, and Sn.

[0160] According to this aspect, the capacitance can be increased.

[0161] In the capacitor (1; 1A; 1B) according to the sixth aspect, in the fifth aspect, the dielectric layer (4) contains an oxide of a metal selected from the group consisting of Zr, Ta, Hf, Nb and La.

[0162] According to this embodiment, the capacitance can be increased compared to when the dielectric material of the dielectric layer (4) is an oxide of the first metal.

[0163] A capacitor (1; 1A; 1B) according to a seventh aspect is based on any one of the first to sixth aspects. In the intermediate layer (3), the ratio of the number of atoms of the second metal to the total number of atoms of the first metal and the second metal is 11 atom% or more.

[0164] According to this aspect, the capacitance can be increased.

[0165] The capacitor (1B) according to an eighth aspect is the capacitor according to any one of the first to sixth aspects, further comprising a second intermediate layer (6). The second intermediate layer (6) is different from the first intermediate layer (3), which is the intermediate layer (3). The second intermediate layer (6) is located between the dielectric layer (4) and the second conductive member (5). The second conductive member (5) includes a third metal. The second intermediate layer (6) includes a metal oxide that is an oxide of the third metal and a metal compound that is a compound of a fourth metal different from the third metal.

[0166] According to this embodiment, the capacitance can be increased compared to when a layer made of an oxide of a third metal is interposed between the dielectric layer (4) and the second conductive member (5).

[0167] In the capacitor (1; 1A) according to the ninth aspect, in any one of the first to sixth aspects, the second conductive member (5) contains a conductive polymer.

[0168] In the capacitor (1; 1A; 1B) according to the tenth aspect, in any one of the first to ninth aspects, the thickness of the dielectric layer (4) is 20 nm or less.

[0169] A method for manufacturing a capacitor (1) according to an eleventh aspect is a method for manufacturing a capacitor (1) comprising a first conductive member (2), a dielectric layer (4), a second conductive member (5), and an intermediate layer (3). The first conductive member (2) includes a first metal. The dielectric layer (4) overlies the first conductive member (2). The second conductive member (5) overlies the dielectric layer (4). The intermediate layer (3) is located between the first conductive member (2) and the dielectric layer (4). The intermediate layer (3) includes a metal oxide that is an oxide of the first metal and a metal compound that is a compound of a second metal different from the first metal. The method for manufacturing a capacitor (1) includes preparing a first conductive member (2), forming a reaction layer (33) containing a compound of a second metal on a native oxide film (23) containing an oxide of a first metal formed on the first conductive member (2), forming a dielectric layer (4) on the reaction layer (33), causing the native oxide film (23) and the reaction layer (33) to react with each other by heat treatment to form an intermediate layer (3), and forming a second conductive member (5) on the dielectric layer (4).

[0170] According to this aspect, it is possible to increase the capacitance of the capacitor (1).

[0171] A capacitor (1C) according to a twelfth aspect includes a first conductive member (2), a dielectric layer (4), a second conductive member (5), and an intermediate layer (7). The dielectric layer (4) overlies the first conductive member (2). The second conductive member (5) includes a first metal. The second conductive member (5) overlies the dielectric layer (4). The intermediate layer (7) is located between the dielectric layer (4) and the second conductive member (5). The intermediate layer (7) includes a metal oxide that is an oxide of the first metal and a metal compound that is a compound of a second metal different from the first metal.

[0172] According to this aspect, it is possible to increase the capacitance.

[0173] In the capacitor (1C) according to the thirteenth aspect, in the twelfth aspect, the band gap of the metal compound is smaller than the band gap of the metal oxide.

[0174] According to this embodiment, the conductivity of the intermediate layer (7) can be improved.

[0175] In a capacitor (1C) according to a fourteenth aspect, in the twelfth or thirteenth aspect, the metal compound is an oxide of the second metal or a nitride of the second metal.

[0176] According to this embodiment, the conductivity of the intermediate layer (7) can be improved.

[0177] In the capacitor (1C) according to the fifteenth aspect, in any one of the twelfth to fourteenth aspects, the dielectric constant of the dielectric material of the dielectric layer (4) is higher than the dielectric constant of the metal oxide.

[0178] According to this embodiment, the capacitance can be made larger than when the dielectric material of the dielectric layer (4) is a metal oxide (oxide of the first metal).

[0179] In a capacitor (1C) according to a sixteenth aspect, in any one of the twelfth to fifteenth aspects, the first metal is one metal selected from the group consisting of Al, Ta, Si, Nb, and Ni, and the second metal is one metal selected from the group consisting of Ti, Cu, Zn, Ga, In, and Sn.

[0180] According to this aspect, the capacitance can be increased.

[0181] In a capacitor (1C) according to a seventeenth aspect, in the sixteenth aspect, the dielectric layer (4) contains an oxide of a metal selected from the group consisting of Zr, Ta, Hf, Nb, and La.

[0182] According to this embodiment, the capacitance can be increased compared to when the dielectric material of the dielectric layer (4) is an oxide of the first metal.

[0183] In a capacitor (1C) according to an eighteenth aspect, in any one of the twelfth to seventeenth aspects, the thickness of the dielectric layer (4) is 20 nm or less.

[0184] 1, 1A, 1B, 1C Capacitor 2 First conductive member 3 Intermediate layer (first intermediate layer) 4 Dielectric layer 5 Second conductive member 23 Native oxide film 33 Reaction layer 6 Second intermediate layer 7 Intermediate layer

Claims

1. A capacitor comprising: a first conductive member comprising a first metal; a dielectric layer overlying the first conductive member; a second conductive member overlying the dielectric layer; and an intermediate layer positioned between the first conductive member and the dielectric layer, wherein the intermediate layer comprises a metal oxide that is an oxide of the first metal and a metal compound that is a compound of a second metal different from the first metal.

2. The capacitor according to claim 1, wherein the band gap of the metal compound is smaller than the band gap of the metal oxide.

3. The capacitor according to claim 1 or 2, wherein the metal compound is an oxide of the second metal or a nitride of the second metal.

4. The capacitor according to any one of claims 1 to 3, wherein the dielectric constant of the dielectric material of the dielectric layer is higher than the dielectric constant of the metal oxide.

5. The capacitor according to any one of claims 1 to 4, wherein the first metal is one metal selected from the group consisting of Al, Ta, Si, Nb, and Ni, and the second metal is one metal selected from the group consisting of Ti, Cu, Zn, Ga, In, and Sn.

6. The capacitor of claim 5, wherein the dielectric layer comprises an oxide of a metal selected from the group consisting of Zr, Ta, Hf, Nb, and La.

7. The capacitor according to any one of claims 1 to 6, wherein in the intermediate layer, the ratio of the number of atoms of the second metal to the total number of atoms of the first metal and the second metal is 11 atom % or more.

8. The capacitor according to any one of claims 1 to 6, further comprising a second intermediate layer different from the first intermediate layer and positioned between the dielectric layer and the second conductive member, wherein the second conductive member includes a third metal, and the second intermediate layer includes a metal oxide that is an oxide of the third metal, and a metal compound that is a compound of a fourth metal different from the third metal.

9. The capacitor according to any one of claims 1 to 6, wherein the second conductive member includes a conductive polymer.

10. The capacitor according to any one of claims 1 to 9, wherein the thickness of the dielectric layer is 20 nm or less.

11. A method for manufacturing a capacitor comprising: a first conductive member containing a first metal; a dielectric layer overlying the first conductive member; a second conductive member overlying the dielectric layer; and an intermediate layer located between the first conductive member and the dielectric layer, wherein the intermediate layer contains a metal oxide that is an oxide of the first metal and a metal compound that is a compound of a second metal different from the first metal, the method comprising: preparing the first conductive member; forming a reaction layer containing a compound of the second metal on a native oxide film containing an oxide of the first metal that is formed on the first conductive member; forming a dielectric layer on the reaction layer; reacting the native oxide film and the reaction layer by heat treatment to form the intermediate layer; and forming the second conductive member on the dielectric layer.

12. A capacitor comprising: a first conductive member; a dielectric layer overlying the first conductive member; a second conductive member including a first metal and overlying the dielectric layer; and an intermediate layer located between the dielectric layer and the second conductive member, wherein the intermediate layer includes a metal oxide that is an oxide of the first metal and a metal compound that is a compound of a second metal different from the first metal.

13. The capacitor of claim 12, wherein the band gap of the metal compound is smaller than the band gap of the metal oxide.

14. The capacitor according to claim 12 or 13, wherein the metal compound is an oxide of the second metal or a nitride of the second metal.

15. The capacitor according to any one of claims 12 to 14, wherein the dielectric constant of the dielectric material of the dielectric layer is higher than the dielectric constant of the metal oxide.

16. The capacitor according to any one of claims 12 to 15, wherein the first metal is one metal selected from the group consisting of Al, Ta, Si, Nb, and Ni, and the second metal is one metal selected from the group consisting of Ti, Cu, Zn, Ga, In, and Sn.

17. The capacitor of claim 16, wherein the dielectric layer comprises an oxide of a metal selected from the group consisting of Zr, Ta, Hf, Nb, and La.

18. The capacitor according to any one of claims 12 to 17, wherein the thickness of the dielectric layer is 20 nm or less.

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