Capacitor, electric circuit, circuit board, and device

Abstract

The capacitor includes a first electrode, a second electrode, and a dielectric, the dielectric being disposed between the first electrode and the second electrode, the dielectric including a crystal having a composition of APb2X5, where A is a cation that is a molecular ion including a nitrogen atom, and X is a halogen element.

Description

[Technical field]

[0001] The present disclosure relates to capacitors, electric circuits, circuit boards, and devices. [Background technology]

[0002] Traditionally, halides have been used in devices such as perovskite solar cells.

[0003] For example, Patent Document 1 describes a ferroelectric memory element having a ferroelectric layer sandwiched between a pair of electrodes. The ferroelectric layer contains a predetermined halide-based organic-inorganic hybrid perovskite compound or an inorganic perovskite compound. Examples of the halide-based organic-inorganic hybrid perovskite compound include CH3NH3PbI3, C2H5NH3PbI4, CH3NH3SnI3, and C2H5NH3SnI4. Examples of the inorganic perovskite compound include CsSnI3. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2016-171152 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present disclosure provides a capacitor that is advantageous in terms of high withstand voltage. [Means for solving the problem]

[0006] The capacitor of the present disclosure comprises: A first electrode; A second electrode; and a dielectric disposed between the first electrode and the second electrode, the dielectric including a crystal having a composition of APb2X5; In the above composition, A is a cation that is a molecular ion containing a nitrogen atom, and X is a halogen element. Effect of the Invention

[0007] According to the present disclosure, a capacitor that is advantageous in terms of high withstand voltage can be provided. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a cross-sectional view showing an example of a capacitor according to the present disclosure. [Figure 2A] FIG. 2A shows the crystal structure of CsPb2Br5. [Figure 2B] FIG. 2B shows the crystal structure of (NH4)Pb2Br5. [Figure 3A] FIG. 3A shows the crystal structure of CsPbBr3. [Figure 3B] FIG. 3B shows the crystal structure of CsPbBr3. [Figure 4A] FIG. 4A shows the crystal structure of CsPb2Br5. [Figure 4B] FIG. 4B shows the crystal structure of CsPb2Br5. [Figure 4C] FIG. 4C shows the crystal structure of CsPb2Br5. [Figure 5A] FIG. 5A is a cross-sectional view showing another example of a capacitor according to the present disclosure. [Figure 5B] FIG. 5B is a cross-sectional view showing yet another example of the capacitor of the present disclosure. [Figure 5C] FIG. 5C is a cross-sectional view showing yet another example of a capacitor according to the present disclosure. [Figure 6A] FIG. 6A is a diagram illustrating a schematic example of an electric circuit according to the present disclosure. [Figure 6B] FIG. 6B is a diagram illustrating a schematic example of a circuit board according to the present disclosure. [Figure 6C] FIG. 6C is a schematic diagram illustrating an example of an apparatus of the present disclosure. [Figure 7]FIG. 7 is a graph showing an XRD pattern of the dielectric material contained in the capacitor according to Example 1. [Figure 8] FIG. 8 is a graph showing the relationship between polarization and electric field intensity of the capacitor according to the first embodiment. [Figure 9] FIG. 9 is a graph showing the relationship between polarization and electric field intensity of the capacitor according to Comparative Example 1. [Figure 10] FIG. 10 is a graph showing the relationship between polarization and electric field intensity of the capacitor according to Comparative Example 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] (Findings on which this disclosure is based) In recent years, electronic devices have become smaller and more highly integrated, and their operating frequencies have become higher. Electronic components used in electronic circuits are also required to be smaller and more highly integrated. For example, if a small capacitor with high capacitance can be provided, it is believed that this will contribute to the miniaturization and high performance of electronic components. The capacitance depends on the relative dielectric constant of the dielectric used in the capacitor, and the higher the relative dielectric constant, the larger the capacitance. Capacitors using oxide dielectrics have been widely developed as dielectrics that exhibit high relative dielectric constants. However, oxide synthesis often requires firing at high temperatures of 500°C or higher, which tends to increase the manufacturing cost of capacitors. In addition, oxides often have a small elastic constant, making it difficult to increase the filling rate of a powder pressure-molded body. For this reason, it is difficult to improve the performance of capacitors. In addition, oxides do not have high strength against bending stress.

[0010] Halides may be able to eliminate such disadvantages of oxides. Halides are generally highly soluble in water and organic solvents, so they can be easily synthesized by coating methods. In addition, since halides can be synthesized at low temperatures of 200°C or less, it is expected that the manufacturing cost of capacitors can be reduced. In addition, halides can be formed on substrates such as films that do not have high durability against high temperatures, and flexible capacitors can be realized. On the other hand, according to the study by the present inventors, since conventional halide dielectrics are composed of inorganic elements, the solubility of the halide dielectrics in solvents is low. For this reason, when a coating film containing a halide dielectric is formed by a coating method such as spin coating, the film tends to be non-uniform. Non-uniformity in the film can cause leakage current under an electric field. Thus, it was found that conventional coating films containing halide dielectrics have the problem that it is difficult to increase the withstand voltage.

[0011] In view of these circumstances, the inventors have conducted extensive research into whether it is possible to increase the withstand voltage of a film containing a halide by making a molecular ion exist as a part of the cation in the halide. As a result, the inventors have newly discovered that the withstand voltage of a halide containing a specific molecular ion, a cation, and lead is likely to be increased. Based on this new knowledge, the inventors have devised the capacitor of the present disclosure.

[0012] (Embodiment) Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The present disclosure is not limited to the following embodiments.

[0013] Fig. 1 is a cross-sectional view showing an example of a capacitor according to the present disclosure. As shown in Fig. 1, a capacitor 1a includes a first electrode 11, a second electrode 12, and a dielectric 20. The dielectric 20 is disposed between the first electrode 11 and the second electrode 12. The dielectric 20 includes a crystal having a composition of APb2X5. In this composition, A is a cation that is a molecular ion containing a nitrogen atom, and X is a halogen element.

[0014] The solubility of cation A in the solvent tends to be high. As a result, dielectric 20 tends to exist uniformly between first electrode 11 and second electrode 12, and capacitor 1a tends to have a high withstand voltage.

[0015] FIG. 2A is a diagram showing the crystal structure of CsPb2Br5. FIG. 2B is a diagram showing the crystal structure of (NH4)Pb2Br5. CsPb2Br5 is Cs + , Pb 2+ , and Br - On the other hand, (NH4)Pb2Br5 is composed of the inorganic ions CsPb2Br5. + NH4 + It has a structure substituted by a cation. The solubility of halide raw materials that do not contain molecular ions, such as CsPb2Br5, in a solvent tends to be low. For example, if 0.5 millimoles (mmol) of CsBr and 1 mmol of PbBr2 are added to a 1 ml mixed solvent of dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF) and heated at 80 degrees for 1 hour, the raw materials remain undissolved and do not dissolve completely, resulting in a cloudy solution. Therefore, if this solution is used to form a film by a coating method such as spin coating, a non-uniform film is obtained. Non-uniformity in the film can cause leakage current under an electric field. Since the solubility of CsBr in a solvent is low, it is thought that a non-uniform film is obtained. On the other hand, for example, NH4Br containing molecular ions containing nitrogen atoms dissolves instantly in the solvent, and even if NH4Br is added to a solvent at the same molar concentration as that of CsBr in a solution containing CsBr, a colorless and transparent solution is obtained. In this manner, when A in dielectric 20 of capacitor 1a is a molecular ion containing a nitrogen atom, dielectric 20 tends to exist in a uniform state, and capacitor 1a tends to have a high withstand voltage.

[0016] The cation A in the above composition may contain only nitrogen and hydrogen atoms, or may further contain carbon atoms.

[0017] The cation A in the above composition is, for example, an ammonium ion represented by the following formula (I):1 , R 2 , R 3 , and R 4 are each independently a hydrogen atom, an alkyl group, an aryl group, or NH2. In this case, the solubility of the cation A, which is a molecular ion, in the solvent tends to be high, and the capacitor 1a tends to have a high withstand voltage.

[0018] [ka]

[0019] In formula (I), R 1 and R 2 are each independently a hydrogen atom, an alkyl group, or an aryl group, and R 3 and R 4 may each be a hydrogen atom. In this case, the solubility of the cation A, which is a molecular ion, in the solvent tends to be high, and the capacitor 1a tends to have a high withstand voltage.

[0020] In formula (I), R 1 , R 2 , R 3 , and R 4 may each be a hydrogen atom. In this case, the solubility of the cation A, which is a molecular ion, in the solvent tends to be high, and the capacitor 1a tends to have a high withstand voltage.

[0021] In formula (I), for example, R 1 is NH2 and R 2 , R 3 , and R 4 may each be a hydrogen atom. In this case, the solubility of the cation A, which is a molecular ion, in the solvent tends to be high, and the capacitor 1a tends to have a high withstand voltage.

[0022] The cation A in the above composition is an ammonium ion represented by formula (I) above, R 1 , R 2 , R 3 , or R 4When is an alkyl group, the alkyl group is not limited to a specific alkyl group. For example, the number of carbon atoms in the alkyl group is 1 to 20. At least one hydrogen atom in the alkyl group may be substituted or unsubstituted.

[0023] The alkyl group may be a saturated radical having a straight or branched chain. At least one hydrogen atom in the saturated radical may be substituted or unsubstituted. The alkyl group is, for example, a saturated hydrocarbon radical having a straight or branched chain with 1 to 20 carbon atoms. At least one hydrogen atom in the saturated hydrocarbon radical may be substituted or unsubstituted. The alkyl group may be an alkyl group having 1 to 20 carbon atoms. Examples of such alkyl groups are methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl. The alkyl group may be an alkyl group having 1 to 6 carbon atoms. Examples of such alkyl groups are methyl, ethyl, propyl, butyl, pentyl, and hexyl. The alkyl group may be an alkyl group having 1 to 4 carbon atoms. Examples of such alkyl groups are methyl, ethyl, i-propyl, n-propyl, t-butyl, s-butyl, n-butyl, and pentyl.

[0024] When at least one hydrogen atom in the alkyl group is replaced by a substituent, the substituent may include, for example, one or more substituents selected from the group consisting of an alkyl group, an aryl group, a cyano group, and an amino group. The alkyl group that is a substituent may have 1 to 20 carbon atoms. At least one hydrogen atom in the alkyl group that is a substituent may be substituted or unsubstituted. At least one hydrogen atom in the aryl group may be substituted or unsubstituted. Examples of the substituent are an alkylamino group, a dialkylamino group, an arylamino group, a diarylamino group, an arylalkylamino group, an amido group, an acylamido group, a hydroxy group, an oxo group, a halo group, a carboxy group, an ester group, an acyl group, an acyloxy group, an alkoxy group, an aryloxy group, a haloalkyl group, a sulfonic acid group, a sulfhydryl group, an alkylthio group, an arylthio group, a sulfonyl group, a phosphoric acid group, a phosphoric acid ester group, a phosphonic acid group, and a phosphonic acid ester group. Examples of the substituted alkyl group are a haloalkyl group, a hydroxyalkyl group, an aminoalkyl group, an alkoxyalkyl group, and an alkaryl group. An alkaryl group is, for example, an alkyl group having 1 to 20 carbon atoms, in which at least one hydrogen atom is replaced by an aryl group. The alkaryl group is not limited to a specific alkaryl group. Examples of alkaryl groups are benzyl, benzhydryl, trityl, phenethyl, styryl, and cinnamyl.

[0025] The cation A in the above composition is an ammonium ion represented by formula (I) above, R 1 , R 2 , R 3 , or R 4When is an aryl group, the aryl group is not limited to a specific aryl group. The aryl group is, for example, a monocyclic or bicyclic aromatic group. The aryl group has a ring structure containing, for example, 6 to 14 carbon atoms, preferably 6 to 10 carbon atoms. At least one hydrogen atom in the aryl group may be substituted or unsubstituted. Examples of the aryl group are a phenyl group, a naphthyl group, an indenyl group, and an indanyl group. When the aryl group is substituted, the aryl group has one or more substituents selected from the group consisting of, for example, an unsubstituted alkyl group having 1 to 6 carbon atoms, an unsubstituted aryl group, a cyano group, an amino group, an alkylamino group, a dialkylamino group having 1 to 10 carbon atoms, an arylamino group, a diarylamino group, an arylalkylamino group, an amido group, an acylamide group, a hydroxy group, a halo group, a carboxy group, an ester group, an acyl group, an acyloxy group, an alkoxy group having 1 to 20 carbon atoms, an aryloxy group, a haloalkyl group, a sulfhydryl group, an alkylthio group having 1 to 10 carbon atoms, an arylthio group, a sulfonic acid group, a phosphoric acid group, a phosphoric acid ester group, a phosphonic acid group, a phosphonic acid ester group, and a sulfonyl group. The aryl group may have no substituent, one substituent, two substituents, or three substituents. The substituted aryl group may be a single alkylene group having 1 to 6 carbon atoms, or -XR 9 -or-XR 9 R may be substituted at the 2-position with a bidentate group represented by -X-. 9 is an alkylene group having 1 to 6 carbon atoms. X is O, S, and NR 10 R 10is a hydrogen atom, an aryl group, or an alkyl group having 1 to 6 carbon atoms. The substituted aryl group may be an aryl group fused to a cycloalkyl group or an aryl group fused to a heterocyclyl group. The ring atoms of the aryl group may contain one or more heteroatoms, like the heteroaryl group. Such heteroaryl groups are substituted or unsubstituted monocyclic or bicyclic heteroaromatic groups containing 6 to 10 atoms in the ring portion containing one or more heteroatoms. The heteroaryl group may, for example, be a five- or six-membered ring and contain at least one heteroatom selected from O, S, N, P, Se, and Si. The heteroaryl group may, for example, contain one, two, or three heteroatoms. Examples of heteroaryl groups include pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, furanyl, thienyl, pyrazolidinyl, pyrrolyl, oxazolyl, oxadiazolyl, isoxazolyl, thiadiazolyl, thiazolyl, isothiazolyl, imidazolyl, pyrazolyl, quinolyl, and isoquinolyl. Heteroaryl groups can be unsubstituted or substituted, for example, as described above for aryl groups. Heteroaryl groups can have zero, one, two, or three substituents.

[0026] In formula (I), R 1 , R 2 , R 3 , and R 4 Each of R is independently, for example, a hydrogen atom, NH, a methyl group, or an ethyl group. 1 , R 2 , R 3 , and R 4 Each of may independently be a hydrogen atom, NH2, or a methyl group.

[0027] The lead ion in the dielectric 20 has, for example, a lone pair of electrons. A lone pair is an electron pair formed by two electrons belonging to a specific atom and is not shared with other atoms. For example, Pb 2+The ion has a lone pair of electrons. Pb 2+ In the ion, two electrons have been removed from Pb, and the two electrons filling the s orbital of the outermost shell form a lone pair. Electrons forming a lone pair are unlikely to bond with surrounding ions, and may result in an unstable electronic state or a special crystal structure. For this reason, if the lead ion in the dielectric 20 has a lone pair, the relative dielectric constant of the dielectric 20 tends to be high. On the other hand, the lead ion Pb 2+ In addition to ions, Pb 4+ ions may also be present. 4+ In the Pb ion, four electrons have been removed from the Pb, leaving the outermost s orbital empty. 4+ The ions do not have lone pairs of electrons. In this case, a crystal structure with a low coordination number is easily formed, and the relative dielectric constant of the material is not easily increased.

[0028] For example, all of the lead ions in the dielectric 20 may have lone pairs, or only a portion of the lead ions in the dielectric 20 may have lone pairs.

[0029] X in the dielectric 20 includes, for example, at least one selected from the group consisting of F, Cl, Br and I. In this case, the dielectric 20 is more likely to have a high relative dielectric constant.

[0030] The dielectric 20 has, for example, an inverse perovskite structure. With such a structure, the dielectric 20 is more likely to have a high relative dielectric constant.

[0031] The reversed perovskite structure is a structure in which the arrangement of cations and anions in a normal perovskite compound is reversed, i.e., the positive and negative charges of an ion occupying a specific site in a perovskite compound are reversed to the positive and negative charges of an ion occupying the specific site in a compound with the reversed perovskite structure.

[0032] 3A and 3B are diagrams showing the crystal structure of CsPbBr3. FIG. 3B is a diagram showing the crystal structure shown in FIG. 3A viewed along the negative direction of the c-axis. CsPbBr3 has a perovskite structure. FIG. 4A, FIG. 4B, and FIG. 4C are diagrams showing the crystal structure of CsPb2Br5. FIG. 4B is a diagram showing the crystal structure of CsPb2Br5 represented by a coordination polyhedron with an anion at the center. FIG. 4C is a diagram showing the crystal structure shown in FIG. 4B viewed along the negative direction of the c-axis. CsPb2Br5 has an inverse perovskite structure. As shown in FIG. 3A, in CsPbBr3, Cs is arranged at the A site of the perovskite structure, Pb is arranged at the B site, and Br is arranged at the X site. On the other hand, as shown in Fig. 4B, in CsPb2Br5, Br4 is arranged at the site corresponding to the A site of the perovskite structure, Br is arranged at the site corresponding to the B site, and Cs or Pb is arranged at the site corresponding to the X site. In other words, CsPb2Br5 is expressed as (Br4)Br(CsPb2) in the notation ABX3.

[0033] When the dielectric 20 including the crystal having the composition of APb2X5 has an inverse perovskite structure, for example, Cs is replaced with a cation A, which is a molecular ion, in the crystal structure shown in FIG. 4B. In the inverse perovskite structure shown in FIG. 4B, cations are arranged at the vertices of a plurality of octahedra that share the vertices, and there is a site where an anion is arranged at the center of the octahedron. This makes it easier for ions to be aligned along a straight line in the inverse perovskite structure, and polarization is easier to increase. This makes it easier for the dielectric 20 to have a high relative dielectric constant.

[0034] The anti-perovskite structure of halides with the composition APb2X5 is the NH4Pb2Br5 type structure, the Cs3CoCl5 type structure, the La2CuSbS5 type structure, the La4FeSb2S 10 type structure, Ba4In2Te2S5 type structure, Y2HfS5 type structure, or TlPb2Cl5 type structure.

[0035] The relative dielectric constant of the dielectric 20 is not limited to a specific value. The relative dielectric constant of the dielectric 20 at room temperature is, for example, 30 or more at 1 MHz, and may be 35 or more, 40 or more, 45 or more, 50 or more, 60 or more, 70 or more, 80 or more, 90 or more, or 100 or more. The room temperature is, for example, a specific temperature in the range of 20°C to 25°C. The relative dielectric constant of the dielectric 20 at room temperature is, for example, 10,000 or less at 1 MHz. In other words, the relative dielectric constant of the dielectric 20 at room temperature is, for example, 30 or more and 10,000 or less at 1 MHz.

[0036] As shown in FIG. 1, in the capacitor 1a, the dielectric 20 is formed as, for example, a film. The method of disposing the dielectric 20 on the capacitor 1a is not limited to a specific method. The dielectric 20 may be formed by, for example, spin coating, inkjet, die coating, roll coating, bar coating, Langmuir-Blodgett, dip coating, or spray coating. This makes it easier for the dielectric 20 to exist in a uniform state between the first electrode 11 and the second electrode 12, and makes it easier for the capacitor 1a to have a high withstand voltage. The dielectric 20 may be formed by sputtering, anodization, vacuum evaporation, pulsed laser deposition (PLD), atomic layer deposition (ALD), or chemical vapor deposition (CVD).

[0037] 1, the dielectric 20 is disposed, for example, between the first electrode 11 and the second electrode 12 in the thickness direction of the dielectric 20. The second electrode 12 covers, for example, at least a portion of the dielectric 20.

[0038] The material forming the first electrode 11 and the second electrode 12 is not limited to a specific material. Each of the first electrode 11 and the second electrode 12 includes, for example, a metal. The first electrode 11 includes, for example, a valve metal. Examples of the valve metal are Al, Ta, Nb, Pb, Sn, and Bi. The first electrode 11 includes, for example, at least one valve metal selected from the group consisting of Al, Ta, Nb, Pb, Sn, and Bi. The first electrode 11 may include a precious metal such as gold or platinum, may include nickel, or may include a metal element of group 13, group 14, or group 15.

[0039] The second electrode 12 may contain, for example, a valve metal such as Al, Ta, Nb, Pb, Sn, or Bi, a precious metal such as gold, silver, or platinum, nickel, or a metal element of Group 13, Group 14, or Group 15. The second electrode 12 contains, for example, at least one selected from the group consisting of Al, Ta, Nb, Bi, gold, silver, platinum, and nickel.

[0040] 1, the first electrode 11 has a principal surface 11p. One principal surface of the dielectric 20 is in contact with the principal surface 11p, for example. The second electrode 12 has a principal surface 12p parallel to the principal surface 11p. The other principal surface of the dielectric 20 is in contact with the principal surface 12p, for example.

[0041] Fig. 5A is a cross-sectional view showing another example of a capacitor of the present disclosure. Capacitor 1b shown in Fig. 5A is configured similarly to capacitor 1a, except for parts that will be particularly described. Components of capacitor 1b that are the same as or correspond to those of capacitor 1a are given the same reference numerals, and detailed description will be omitted. The description of capacitor 1a also applies to capacitor 1b as long as there is no technical contradiction. The same also applies to capacitor 1c and capacitor 1d described below.

[0042] The capacitor 1b shown in Fig. 5A is an electrolytic capacitor. As shown in Fig. 5A, in the capacitor 1b, at least a part of the first electrode 11 is porous. With such a configuration, the surface area of ​​the first electrode 11 tends to be large, and the capacitor 1b tends to have a higher capacitance. Such a porous structure can be formed by, for example, a method such as etching a metal foil and sintering a powder.

[0043] 5A, for example, a film of a dielectric 20 is formed on the surface of the porous portion of the first electrode 11. The method of forming the dielectric 20 may be, for example, spin coating, inkjet, die coating, roll coating, bar coating, Langmuir-Blodgett, dip coating, or spray coating. The dielectric 20 may be formed by, for example, sputtering, anodization, vacuum deposition, PLD, ALD, or CVD.

[0044] The first electrode 11 includes a valve metal such as Al, Ta, Nb, Zr, Hf, Pb, Sn, and Bi. The second electrode 12 may include, for example, a solidified silver-containing paste, a carbon material such as graphite, or both the above-mentioned solidified material and a carbon material.

[0045] In capacitor 1b, for example, electrolyte 13 is disposed between first electrode 11 and second electrode 12. In detail, electrolyte 13 is disposed between dielectric 20 and second electrode 12. In capacitor 1b, for example, second electrode 12 and electrolyte 13 form cathode 15. In capacitor 1b, electrolyte 13 is disposed so as to fill voids around a porous portion of first electrode 11, for example.

[0046] The electrolyte 13 includes, for example, at least one selected from the group consisting of an electrolytic solution and a conductive polymer. Examples of the conductive polymer include polypyrrole, polythiophene, polyaniline, and derivatives thereof. The electrolyte 13 may be a manganese compound such as manganese oxide. The electrolyte 13 may include a solid electrolyte.

[0047] The electrolyte 13 containing a conductive polymer can be formed by performing chemical polymerization, electrolytic polymerization, or both chemical polymerization and electrolytic polymerization of a raw material monomer on the dielectric 20. The electrolyte 13 containing a conductive polymer may also be formed by depositing a solution or dispersion of the conductive polymer on the dielectric 20.

[0048] Fig. 5B is a cross-sectional view showing yet another example of the capacitor of the present disclosure. In the capacitor 1c shown in Fig. 5B, at least a part of the first electrode 11 is porous. With such a configuration, the surface area of ​​the first electrode 11 is likely to be large, and the capacitor 1c is likely to have a higher capacitance. Such a porous structure can be formed by, for example, a method such as etching a metal foil and sintering a powder.

[0049] 5B, for example, a film including a dielectric 20 is formed on the upper part of the porous part of the first electrode 11. For example, spin coating, inkjet, die coating, roll coating, bar coating, Langmuir-Blodgett, dip coating, or spray coating can be used as a method for forming the film including the dielectric 20. In the capacitor 1c, the dielectric 20 is disposed so as to fill, for example, the voids around the porous part of the first electrode 11.

[0050] FIG. 5C is a cross-sectional view showing yet another example of the capacitor of the present disclosure. In the capacitor 1d shown in FIG. 5C, the dielectric 20 is formed as, for example, a film. In this film, a different dielectric 22 different from the dielectric 20 is dispersed and arranged. As a method for forming this film, spin coating, inkjet, die coating, roll coating, bar coating, Langmuir-Blodgett, dip coating, or spray coating can be adopted. For example, a film including the dielectric 20 and the different dielectric 22 is obtained by forming a coating of a precursor liquid containing the raw material of the dielectric 20 and particles of the different dielectric 22 by the above-mentioned method. This film may be formed by sputtering, anodization, vacuum deposition, PLD, ALD, or CVD.

[0051] The heterogeneous dielectric 22 is not limited to a specific dielectric as long as it is a dielectric of a different type from the dielectric 20. The heterogeneous dielectric 22 has, for example, a higher dielectric constant than that of the dielectric 20. The heterogeneous dielectric 22 may be, for example, a perovskite compound such as BaTiO3, PbTiO3, and SrTiO3, or may be a layered perovskite compound. The heterogeneous dielectric 22 may include at least one selected from the group consisting of a Ruddlesden-Popper compound, a Dion-Jacobson compound, a tungsten bronze compound, and a pyrochlore compound.

[0052] The size of the particles of the different dielectric material 22 is not limited to a specific value. The particles of the different dielectric material 22 have a size of, for example, 1 nm or more and 100 nm or less.

[0053] FIG. 6A is a diagram showing a schematic example of an electric circuit according to the present disclosure. The electric circuit 3 includes a capacitor 1a. The electric circuit 3 may be an active circuit or a passive circuit. The electric circuit 3 may be a discharge circuit, a smoothing circuit, a decoupling circuit, or a coupling circuit. Since the electric circuit 3 includes the capacitor 1a, the electric circuit 3 is likely to exhibit a desired performance. For example, the noise in the electric circuit 3 is likely to be reduced by the capacitor 1a. The electric circuit 3 may include a capacitor 1b, 1c, or 1d instead of the capacitor 1a.

[0054] Fig. 6B is a diagram showing a schematic diagram of an example of a circuit board according to the present disclosure. As shown in Fig. 6B, the circuit board 5 includes a capacitor 1a. For example, an electric circuit 3 including the capacitor 1a is formed on the circuit board 5. The circuit board 5 may be an embedded board or a motherboard. The circuit board 5 may include a capacitor 1b, 1c, or 1d instead of the capacitor 1a.

[0055] FIG. 6C is a diagram showing an example of the device of the present disclosure. As shown in FIG. 6C, the device 7 includes, for example, a capacitor 1a. The device 7 includes, for example, a circuit board 5 including the capacitor 1a. Since the device 7 includes the capacitor 1a, the device 7 is likely to exhibit a desired performance. The device 7 may be an electronic device, a communication device, a signal processing device, or a power supply device. The device 7 may be a server, an AC adapter, an accelerator, or a flat panel display such as a liquid crystal display (LCD). The device 7 may be a USB charger, a solid state drive (SSD), an information terminal such as a PC, a smartphone, or a tablet PC, or an Ethernet switch.

[0056] (Additional Note) From the above description, the following techniques are disclosed.

[0057] (Technology 1) A first electrode; A second electrode; a dielectric disposed between the first electrode and the second electrode; The dielectric material includes a crystal having a composition of APb2X5, In the above composition, A is a cation that is a molecular ion containing a nitrogen atom, and X is a halogen element. Capacitor.

[0058] (Technology 2) The cation further comprises a carbon atom. The capacitor according to technique 1.

[0059] (Technology 3) The cation is an ammonium ion represented by the following formula (I): In the formula (I), R 1 , R 2 , R 3 , and R 4 each independently is a hydrogen atom, an alkyl group, an aryl group, or NH; The capacitor according to technique 1. [ka]

[0060] (Technology 4) In the formula (I), R 1 and R 2 are each independently a hydrogen atom, an alkyl group, or an aryl group, and R 3 and R 4 each of which is a hydrogen atom; The capacitor according to technique 3.

[0061] (Technology 5) In the formula (I), R 1 , R 2 , R 3 , and R 4 each of which is a hydrogen atom; The capacitor according to technique 4.

[0062] (Technology 6) In the formula (I), R 1 is NH2 and R 2 , R 3 , and R 4 each of which is a hydrogen atom; The capacitor according to technique 3.

[0063] (Technology 7) The dielectric has an inverse perovskite structure. A capacitor according to any one of the first to sixth aspects.

[0064] (Technology 8) A capacitor according to any one of the first to seventh aspects of the present invention is provided. Electrical circuit.

[0065] (Technology 9) A capacitor according to any one of the first to seventh aspects of the present invention is provided. Circuit board.

[0066] (Technology 10) A capacitor according to any one of the first to seventh aspects of the present invention is provided. device. EXAMPLES

[0067] The present disclosure will be described in more detail below with reference to examples. Note that the following examples are merely illustrative and the present disclosure is not limited to the following examples.

[0068] <Example 1> A glass substrate manufactured by Nippon Sheet Glass Co., Ltd. was prepared, which had an indium-doped SnO2 layer on its surface. The indium-doped SnO2 layer served as an electrode. The glass substrate was ultrasonically cleaned for 10 minutes in a container filled with ethanol to clean the surface of the glass substrate. The surface was then treated with UV ozone for 30 minutes to remove any adsorbed material on the surface of the glass substrate.

[0069] Next, 0.5 mmol of NH4Br and 1 mmol of PbBr2 were added to 1 ml of a mixed solvent of DMSO and DMF to obtain a mixed solution. The volume ratio of DMSO:DMF in the mixed solvent was 1:4. When the solution was heated to 80 degrees Celsius, NH4Br and PbBr2 were easily dissolved, and impurities were removed by a filter to obtain a coating solution according to Example 1. In a glove box, 80 μl of the coating solution according to Example 1 was dropped onto the indium-doped SnO2 layer of the above glass substrate, and a coating film was obtained by spin coating. The inside of the glove box was filled with N2, and the oxygen concentration was 0.1 ppm (parts per million) or less on a volume basis. Next, the coating film was baked on a hot plate maintained at 80 degrees Celsius for 30 minutes. In this way, a dielectric layer was formed. This dielectric layer mainly contained an inverse perovskite compound having a composition of NH4Pb2Br5. Finally, gold was evaporated onto this dielectric layer to form an electrode. In this manner, the capacitor according to Example 1 was obtained.

[0070] (Crystal structure analysis) In order to identify the crystal structure of the dielectric material contained in the dielectric layer of the capacitor according to Example 1, an X-ray diffraction (XRD) measurement was performed. In this measurement, Cu-Kα rays were used as X-rays, and the measurement was performed under a dry argon atmosphere. FIG. 7 is a graph showing the XRD pattern of the dielectric material contained in the dielectric layer of the capacitor according to Example 1. In FIG. 7, the horizontal axis is the diffraction angle 2θ [degrees], and the vertical axis is the relative intensity of the X-ray diffraction intensity. The lower part of FIG. 7 shows the simulation result of the XRD pattern of KSn2Cl5 of (NH4)PbBr5 type having an inverse perovskite structure. This suggests that the dielectric material contained in the dielectric layer of the capacitor according to Example 1 has an inverse perovskite structure.

[0071] (composition analysis) The contents of N, Pb, and Br per unit weight of the dielectric material contained in the dielectric layer of the capacitor according to Example 1 were measured by XPS measurement using an X-ray photoelectron spectroscopy (XPS) device PHI VersaProbe 2 manufactured by ULVAC-PHI, Inc. Taking into account the composition assumed from the results of XRD measurement, the N:Pb:Br molar ratio was calculated based on the contents of N, Pb, and Br obtained from the results of XPS measurement. As a result, it was found that the dielectric material contained in the dielectric layer of the capacitor according to Example 1 had a relationship of N substance amount:Pb substance amount:Br substance amount=1:2:5, similar to the molar ratio of the raw materials.

[0072] (Evaluation of withstand voltage and polarization) A Polarization-Electric field (PE) measurement was performed on the capacitor of Example 1 using a ferroelectric tester Premier II manufactured by Radiant Technology, and a P-E curve for the capacitor of Example 1 was obtained. The dielectric properties of the capacitor of Example 1 were evaluated based on this P-E curve. FIG. 8 is a graph (P-E curve) showing the relationship between polarization and electric field strength of the capacitor of Example 1. In FIG. 8, the vertical axis indicates polarization, and the horizontal axis indicates electric field strength. The maximum value of the electric field strength in the P-E curve was determined to be the withstand voltage of the capacitor of Example 1. The withstand voltage of Example 1 was 418 kV / cm, and the maximum polarization was 1.39 μC / cm 2 The results are shown in Table 1.

[0073] <Example 2> A coating solution according to Example 2 was obtained in the same manner as in Example 1, except that 0.375 mmol of NH4Br, 0.75 mmol of PbBr2, 0.125 mmol of NH4Cl, and 0.25 mmol of PbCl2 were added to 1 ml of a mixed solvent of DMSO and DMF. A capacitor according to Example 2 was produced in the same manner as in Example 1, except that the coating solution according to Example 2 was used instead of the coating solution according to Example 1. The composition of the dielectric material contained in the dielectric layer of the capacitor according to Example 2 was determined based on XRD measurement and XPS measurement in the same manner as in Example 1. The crystal structure of the dielectric material contained in the dielectric layer of the capacitor according to Example 2 was determined based on XRD measurement in the same manner as in Example 1. The P-E curve of the capacitor according to Example 2 was obtained, and the withstand voltage and maximum polarization were determined in the same manner as in Example 1. The results are shown in Table 1.

[0074] <Example 3> A coating solution according to Example 3 was obtained in the same manner as in Example 1, except that 0.25 mmol of NH4Br, 0.5 mmol of PbBr2, 0.25 mmol of NH4Cl, and 0.5 mmol of PbCl2 were added to 1 ml of a mixed solvent of DMSO and DMF. A capacitor according to Example 3 was produced in the same manner as in Example 1, except that the coating solution according to Example 3 was used instead of the coating solution according to Example 1. The composition of the dielectric material contained in the dielectric layer of the capacitor according to Example 3 was determined based on XPS measurement in the same manner as in Example 1. The crystal structure of the dielectric material contained in the dielectric layer of the capacitor according to Example 3 was determined based on XRD measurement and XRD measurement in the same manner as in Example 1. The P-E curve of the capacitor according to Example 3 was obtained, and the withstand voltage and maximum polarization were determined in the same manner as in Example 1. The results are shown in Table 1.

[0075] <Example 4> A coating solution according to Example 4 was obtained in the same manner as in Example 1, except that 0.5 mmol of NH4Cl and 1 mmol of PbCl2 were added to 1 ml of a mixed solvent of DMSO and DMF. A capacitor according to Example 4 was produced in the same manner as in Example 1, except that the coating solution according to Example 4 was used instead of the coating solution according to Example 1. The composition of the dielectric material contained in the dielectric layer of the capacitor according to Example 4 was determined based on XRD measurement and XPS measurement in the same manner as in Example 1. The crystal structure of the dielectric material contained in the dielectric layer of the capacitor according to Example 4 was determined based on XRD measurement in the same manner as in Example 1. The P-E curve of the capacitor according to Example 4 was obtained, and the withstand voltage and maximum polarization were determined in the same manner as in Example 1. The results are shown in Table 1.

[0076] <Example 5> A coating solution according to Example 5 was obtained in the same manner as in Example 1, except that 0.45 mmol of NH4Br, 0.05 mmol of CH3NH3Br, and 1 mmol of PbBr2 were added to 1 ml of a mixed solvent of DMSO and DMF. A capacitor according to Example 5 was produced in the same manner as in Example 1, except that the coating solution according to Example 5 was used instead of the coating solution according to Example 1. The composition of the dielectric material contained in the dielectric layer of the capacitor according to Example 5 was determined based on XRD measurement and XPS measurement in the same manner as in Example 1. The crystal structure of the dielectric material contained in the dielectric layer of the capacitor according to Example 5 was determined based on XRD measurement in the same manner as in Example 1. The P-E curve of the capacitor according to Example 5 was obtained, and the withstand voltage and maximum polarization were determined in the same manner as in Example 1. The results are shown in Table 1.

[0077] <Example 6> A coating solution according to Example 6 was obtained in the same manner as in Example 1, except that 0.45 mmol of NH4Br, 0.05 mmol of HC(NH2)2Br, and 1 mmol of PbBr2 were added to 1 ml of a mixed solvent of DMSO and DMF. HC(NH2)2Br is represented by the formula NH2CH=NH2 + is a salt having a cation. A capacitor according to Example 6 was produced in the same manner as in Example 1, except that the coating liquid according to Example 6 was used instead of the coating liquid according to Example 1. The composition of the dielectric material contained in the dielectric layer of the capacitor according to Example 6 was determined based on XRD measurement and XPS measurement in the same manner as in Example 1. The crystal structure of the dielectric material contained in the dielectric layer of the capacitor according to Example 6 was determined based on XRD measurement in the same manner as in Example 1. The P-E curve of the capacitor according to Example 6 was obtained, and the withstand voltage and maximum polarization were determined in the same manner as in Example 1. The results are shown in Table 1.

[0078] <Comparative Example 1> A coating solution according to Comparative Example 1 was obtained in the same manner as in Example 1, except that 0.5 mmol of KBr and 1 mmol of PbBr2 were added to 1 ml of a mixed solvent of DMSO and DMF. A capacitor according to Comparative Example 1 was produced in the same manner as in Example 1, except that the coating solution according to Comparative Example 1 was used instead of the coating solution according to Example 1. The composition of the dielectric material contained in the dielectric layer of the capacitor according to Comparative Example 1 was determined based on XRD measurement and XPS measurement in the same manner as in Example 1. The crystal structure of the dielectric material contained in the dielectric layer of the capacitor according to Comparative Example 1 was determined based on XRD measurement in the same manner as in Example 1. The P-E curve of the capacitor according to Comparative Example 1 was obtained, and the withstand voltage and maximum polarization were determined in the same manner as in Example 1. The results are shown in Table 1. FIG. 9 is a graph (P-E curve) showing the relationship between polarization and electric field strength of the capacitor according to Comparative Example 1. In FIG. 9, the vertical axis indicates polarization, and the horizontal axis indicates electric field strength.

[0079] <Comparative Example 2> A coating solution according to Comparative Example 2 was obtained in the same manner as in Example 1, except that 0.5 mmol of CsBr and 1 mmol of PbBr2 were added to 1 ml of a mixed solvent of DMSO and DMF. A capacitor according to Comparative Example 2 was produced in the same manner as in Example 1, except that the coating solution according to Comparative Example 2 was used instead of the coating solution according to Example 1. The composition of the dielectric material contained in the dielectric layer of the capacitor according to Comparative Example 2 was determined based on XRD measurement and XPS measurement in the same manner as in Example 1. The crystal structure of the dielectric material contained in the dielectric layer of the capacitor according to Comparative Example 2 was determined based on XRD measurement in the same manner as in Example 1. The P-E curve of the capacitor according to Comparative Example 2 was obtained, and the withstand voltage and maximum polarization were determined in the same manner as in Example 1. The results are shown in Table 1. FIG. 10 is a graph (P-E curve) showing the relationship between polarization and electric field strength of the capacitor according to Comparative Example 2. In FIG. 10, the vertical axis indicates polarization, and the horizontal axis indicates electric field strength.

[0080] As shown in Table 1, the dielectric material contained in the dielectric layer of the capacitor according to Examples 1 to 6 contains lead ions as metal cations and cations that are molecular ions containing nitrogen atoms. Comparing each Example with Comparative Examples 1 and 2, it is understood that the inclusion of molecular ions containing nitrogen atoms makes it easier for the withstand voltage of the capacitor to be high. In addition, the high withstand voltage also increases the maximum polarization.

[0081] [Table 1] [Industrial Applicability]

[0082] The capacitor according to the present disclosure is useful because it tends to have a high withstand voltage. [Explanation of symbols]

[0083] 1a, 1b, 1c, 1d capacitors 3 Electrical Circuits 5 Circuit Board 7 Equipment 11 First electrode 11p, 12p main surface 12 Second electrode 13 Electrolytes 15 Cathode 20 Dielectrics 22 Different Dielectrics

Claims

1. A first electrode; A second electrode; a dielectric disposed between the first electrode and the second electrode; The dielectric material is APb 2 X 5 The crystals have a composition of In the above composition, A is a cation that is a molecular ion containing a nitrogen atom, and X is a halogen element. Capacitor.

2. The cation further comprises a carbon atom. The capacitor of claim 1 .

3. The cation is an ammonium ion represented by the following formula (I): In the formula (I), R 1 , R 2 , R 3 , and R 4 each independently represents a hydrogen atom, an alkyl group, an aryl group, or NH 2 That is, The capacitor of claim 1 . 【Chemistry 1】

4. In the formula (I), R 1 and R 2 are each independently a hydrogen atom, an alkyl group, or an aryl group, and R 3 and R 4 each of which is a hydrogen atom; The capacitor of claim 3 .

5. In the formula (I), R 1 , R 2 , R 3 , and R 4 each of which is a hydrogen atom; The capacitor of claim 4.

6. In the formula (I), R 1 NH 2 And R 2 , R 3 , and R 4 each of which is a hydrogen atom; The capacitor of claim 3 .

7. The dielectric has an inverse perovskite structure. The capacitor of claim 1 .

8. A capacitor comprising the capacitor according to claim 1 . Electrical circuit.

9. A capacitor comprising the capacitor according to claim 1 . Circuit board.

10. A capacitor comprising the capacitor according to claim 1 . device.

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