Dielectric, capacitor, electric circuit, circuit board, device, and method for manufacturing dielectric

Abstract

The dielectric includes a first portion and a second portion. The first portion includes tantalum oxide and tellurium and is located on a surface of the dielectric. The second portion includes tantalum oxide and is covered by the first portion. The tellurium content in the first portion is higher than the tellurium content in the second portion.

Description

[Technical field]

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

[0002] Dielectric materials containing metal oxides are known in the art.

[0003] For example, Patent Document 1 describes a dielectric material that is a metal oxide material containing a glass phase. The metal oxide material is produced by producing a sol from a mixture consisting of an epoxide, a metal oxide precursor, a glass-forming oxide precursor, and a solvent alone, drying the sol to produce a film, and annealing the film. It is disclosed that the metal oxide precursor may be tantalum ethoxide and the glass-forming oxide may be TeO2. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2016-47797 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present disclosure provides novel dielectric materials comprising tantalum oxide and tellurium. [Means for solving the problem]

[0006] The dielectric material of the present disclosure is a first portion located at a surface of the dielectric, the first portion including tantalum oxide and tellurium; a second portion including tantalum oxide and covered by the first portion, the first portion having a higher tellurium content than the second portion. Effect of the Invention

[0007] According to the present disclosure, novel dielectric materials are provided that include tantalum oxide and tellurium. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a cross-sectional view showing an example of a dielectric material according to the present disclosure. [Diagram 2] FIG. 2 is a cross-sectional view showing an example of a capacitor according to the present disclosure. [Diagram 3] FIG. 3 is a cross-sectional view showing another example of a capacitor according to the present disclosure. [Figure 4A] FIG. 4A is a diagram illustrating a schematic example of an electric circuit according to the present disclosure. [Figure 4B] FIG. 4B is a diagram illustrating an example of a circuit board according to the present disclosure. [Figure 4C] FIG. 4C is a schematic diagram of an example of an apparatus of the present disclosure. [Diagram 5] FIG. 5 is a graph showing the results of X-ray photoelectron spectroscopy (XPS) measurement of the dielectric film according to Example 2. [Figure 6A] FIG. 6A is a graph showing the relationship between the signal intensity of TeO−, TaO3−, and O− in time-of-flight secondary ion mass spectrometry (TOF-SIMS) of the dielectric film according to Example 1 and the depth in the dielectric film. [Figure 6B] FIG. 6B is a graph showing the relationship between the signal intensity of TeO−, TaO3−, and O− in TOF-SIMS of the dielectric film according to Example 2 and the depth in the dielectric film. [Figure 6C] FIG. 6C is a graph showing the relationship between the signal intensity of TeO−, TaO3−, and O− in TOF-SIMS of the dielectric film according to Example 3 and the depth in the dielectric film. [Figure 6D] FIG. 6D is a graph showing the relationship between the signal intensity of TeO−, TaO3−, and O− in TOF-SIMS of the dielectric films according to Examples 1 to 3 and the depth in the dielectric films. [Figure 6E]FIG. 6E is a graph showing the relationship between the signal intensity of TeO−, TaO3−, and O− in TOF-SIMS of the dielectric films according to Examples 1 to 3 and the depth in the dielectric films. [Figure 7A] FIG. 7A is a graph showing the relationship between the capacitance and frequency of the capacitors including the dielectric films according to Example 1 and Comparative Example 1. [Figure 7B] FIG. 7B is a graph showing the relationship between the capacitance and frequency of the capacitors including the dielectric films according to Example 2 and Comparative Example 1. [Figure 7C] FIG. 7C is a graph showing the relationship between the capacitance and frequency of the capacitors including the dielectric films according to Example 3 and Comparative Example 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] (Findings on which this disclosure is based) Tantalum oxide has a high dielectric constant and is therefore widely used as a dielectric material for high-performance capacitors. In recent years, with the increasing performance of electronic devices, capacitors with higher capacitance are in demand, and it is important to further increase the capacitance of capacitors using dielectric materials containing tantalum oxide.

[0010] In view of these circumstances, the present inventors have conducted extensive research into additives to dielectric materials that can increase the capacitance of a capacitor using a dielectric material containing tantalum oxide. As a result, the present inventors have focused on the fact that tellurium is believed to be likely to cause polarization in an oxide film. Through further research, the present inventors have newly discovered that when the tellurium content in a specific portion of a dielectric containing tantalum oxide is higher than the tellurium content in other portions, the capacitance of a capacitor using the dielectric is likely to be high. As a result, the present inventors have devised the dielectric and capacitor of the present disclosure.

[0011] The metal oxide material described in Patent Document 1 is produced by a sol-gel method, and it is believed that components derived from glass-forming oxides such as tellurium are uniformly present throughout this metal oxide material. Therefore, according to the method for producing a metal oxide material described in Patent Document 1, it is believed to be difficult to adjust the tellurium content in a specific portion of the metal oxide material to be higher than the tellurium content in other portions.

[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 the dielectric of the present disclosure. As shown in FIG. 1, the dielectric 1 includes a first portion 11 and a second portion 12. The first portion 11 contains tantalum oxide and tellurium, and has a surface 1a of the dielectric 1. The second portion 12 contains tantalum oxide and is covered by the first portion 11. The tellurium content in the first portion 11 is higher than the tellurium content in the second portion 12. With this configuration, even if tellurium is not uniformly present throughout the dielectric 1, the dielectric 1 is likely to have advantageous characteristics, for example, from the viewpoint of increasing the capacitance of the capacitor. In addition, oxygen vacancies are unlikely to occur in the dielectric 1 due to the tellurium contained in the first portion 11, and the dielectric 1 is likely to have advantageous characteristics from the viewpoint of increasing the durability of the capacitor.

[0014] As shown in FIG. 1, the second portion 12 is in contact with the substrate 2. The substrate 2 is not limited to a specific substrate. The substrate 2 is, for example, a conductor. The conductor is, for example, metallic tantalum. In this case, the substrate 2 can function as an electrode of a capacitor. The second portion 12 is in contact with the substrate 2 made of, for example, metallic tantalum. In this case, the dielectric 1 can be formed by anodization. The substrate 2 may be a dielectric.

[0015] The shape of the dielectric 1 is not limited to a specific shape. As shown in FIG. 1, the dielectric 1 is, for example, a film. In this case, the thickness of the dielectric 1 is not limited to a specific value. The thickness is, for example, 10 nm or more and 1000 nm or less. The thickness of the dielectric 1 may be determined based on the results of TOF-SIMS, or may be determined based on observation of a cross section of the dielectric 1 using an electron microscope such as a scanning electron microscope (SEM) and a transmission electron microscope (TEM). The shape of the dielectric 1 may be particulate or fibrous.

[0016] 1, in the dielectric 1, for example, the first portion 11 forms a first layer 11a, and the second portion 12 forms a second layer 12a. In this case, the thickness t 11a and the thickness t of the second layer 12a 12a The relationship between the thickness of the first layer t 11a For example, the thickness of the first layer t 11a and the thickness of the second layer t 12a TonowaS 12 Even in such a configuration, the dielectric 1 can have advantageous characteristics from the viewpoint of increasing the capacitance of the capacitor. 11a and thickness t 12a can be determined based on the measurement results of TOF-SIMS, for example, according to the method described in the Examples.

[0017] Thickness t of the first layer 11a 11a , and S 12 The thickness t of the first layer may be 30% or less, 25% or less, 20% or less, or 15% or less. 11a For example, sum S 12 is more than 5%.

[0018] The distribution of the tellurium content in the first region 11 is not limited to a specific distribution. For example, in the first region 11, the tellurium content C P1 is the tellurium content C at the second position P2 P2The first position P1 is a position in the first portion 11 that is a first distance away from the surface 1a in a direction perpendicular to the surface 1a. The second position P2 is a position in the first portion 11 that is a second distance away from the surface 1a in a direction perpendicular to the surface 1a. The second distance is shorter than the first distance. Even in such a configuration, the dielectric 1 can have advantageous characteristics from the viewpoint of increasing the capacitance of the capacitor.

[0019] In the dielectric 1, the tellurium content may decrease continuously or discontinuously with increasing distance from the surface 1a in the direction perpendicular to the surface 1a.

[0020] The tellurium content in the first portion 11 is not limited to a specific value. For example, in TOF-SIMS of the dielectric 1, the signal intensity of ions derived from tellurium is lower than the signal intensity of ions derived from tantalum oxide.

[0021] The oxidation number of tellurium contained in the first portion 11 is not limited to a specific value. The first portion 11 contains, for example, tetravalent tellurium. In this case, polarization caused by tellurium in the dielectric 1 is likely to be large, and the dielectric 1 is likely to have more advantageous characteristics in terms of increasing the capacitance of the capacitor. In addition, oxygen vacancies are less likely to occur in the dielectric 1.

[0022] The method for producing the dielectric 1 is not limited to a specific method. The method for producing the dielectric 1 includes, for example, anodizing the metallic tantalum in a state where the metallic tantalum is brought into contact with a solution containing tellurium. According to such a production method, the dielectric 1 having a higher tellurium content in the first portion 11 than the tellurium content in the second portion 12 can be efficiently produced.

[0023] In the anodization in the above manufacturing method, for example, metallic tantalum is used as the anode and platinum is used as the cathode. A predetermined voltage is applied between the anode and the cathode. As a result, anions such as oxide ions attracted toward metallic tantalum, which is the anode, are bonded with ionized tantalum to obtain a dielectric 1 containing tantalum oxide. At this time, tellurium contained in the solution is taken up into the dielectric. As a result, tellurium can be contained in the portion forming the surface of the dielectric 1. On the other hand, although oxide ions can move to the portion of the dielectric 1 in contact with metallic tantalum, tellurium is hardly taken up into this portion. Therefore, although this portion contains tantalum oxide, the tellurium content in this portion is very low.

[0024] The dielectric 1 may be manufactured by a method other than anodization, for example, sputtering. In this case, the material of the substrate 2 may be other than metallic tantalum.

[0025] The dielectric 1 can be used to provide, for example, a capacitor. Fig. 2 is a cross-sectional view showing an example of a capacitor of the present disclosure. As shown in Fig. 2, the capacitor 3a includes a first electrode 21, a second electrode 22, and a dielectric film 10. The dielectric film 10 includes the dielectric 1, and is disposed between the first electrode 21 and the second electrode 22. With this configuration, the capacitor 3a is likely to have a high capacitance.

[0026] 2, the first electrode 21 is in contact with the second portion 12 of the dielectric 1. In addition, the first portion 11 is disposed between the second portion 12 and the second electrode 22 in the thickness direction of the dielectric film 10.

[0027] The first electrode 21 includes, for example, metallic tantalum. In this case, the capacitor 3a can be manufactured by anodization using a solution containing tellurium. The first electrode 21 may be a conductor other than metallic tantalum.

[0028] The material of the second electrode 22 is not limited to a specific material as long as it is conductive. The second electrode 22 may include valve metals such as aluminum, tantalum, niobium, and bismuth, precious metals such as gold and platinum, or nickel. The second electrode 22 may include a carbon material such as graphite.

[0029] In the capacitor 3a, the surface 1a of the dielectric 1 may be in contact with an electrolyte. In this case, the second electrode 22 may contain an electrolyte. This electrolyte is not limited to a specific electrolyte. The electrolyte includes, for example, at least one selected from the group consisting of an electrolytic solution, a solid electrolyte, and a conductive polymer. Examples of the conductive polymer include polypyrrole, polythiophene, polyaniline, and derivatives thereof. The electrolyte may be a manganese compound such as manganese oxide.

[0030] Fig. 3 is a cross-sectional view showing another example of a capacitor according to the present disclosure. Capacitor 3b shown in Fig. 3 is configured similarly to capacitor 3a, except for parts that will be particularly described. Components of capacitor 3b that are the same as or correspond to those of capacitor 3a are given the same reference numerals, and detailed description will be omitted. The description of capacitor 3a also applies to capacitor 3b, unless technically inconsistent.

[0031] 3, in capacitor 3b, dielectric 1 and first electrode 21 form a porous body 15. Second electrode 22 fills pores 15p of porous body 15. With such a configuration, the area of ​​first electrode 21 is increased, and capacitor 3b is likely to have a higher capacitance.

[0032] The porous body 15 is obtained, for example, by anodizing porous tantalum metal in a state where the porous tantalum metal is brought into contact with a solution containing tellurium. The porous tantalum metal can be obtained, for example, by etching a tantalum metal foil or sintering a tantalum metal powder.

[0033] In the capacitor 3b, the second electrode 22 includes, for example, an electrolyte. The electrolyte includes, for example, at least one selected from the group consisting of an electrolytic solution, a solid electrolyte, and a conductive polymer. Examples of the conductive polymer include polypyrrole, polythiophene, polyaniline, and derivatives thereof. The electrolyte may be a manganese compound such as manganese oxide.

[0034] FIG. 4A is a diagram showing a schematic diagram of an example of an electric circuit of the present disclosure. The electric circuit 4 includes a capacitor 3a. The electric circuit 4 may be an active circuit or a passive circuit. The electric circuit 4 may be a discharge circuit, a smoothing circuit, a decoupling circuit, or a coupling circuit. Since the electric circuit 4 includes the capacitor 3a, the electric circuit 4 is likely to exhibit a desired performance. For example, noise is likely to be reduced in the electric circuit 4. The electric circuit 4 may include a capacitor 3b.

[0035] Fig. 4B is a diagram showing a schematic diagram of an example of a circuit board according to the present disclosure. As shown in Fig. 4B, the circuit board 5 includes a capacitor 3a. For example, an electric circuit 4 including the capacitor 3a is formed on the circuit board 5. Since the circuit board 5 includes the capacitor 3a, the circuit board 5 is likely to exhibit the desired performance. The circuit board 5 may be an embedded board or a motherboard. The circuit board 5 may include a capacitor 3b.

[0036] FIG. 4C is a diagram showing a schematic example of a device according to the present disclosure. As shown in FIG. 4C, the device 7 includes a capacitor 3a. The device 7 includes, for example, a circuit board 5 including the capacitor 3a. Since the device 7 includes the capacitor 3a, 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. The device 7 may include a capacitor 3b.

[0037] (Additional Note) From the above description, the following techniques are disclosed.

[0038] (Technology 1) A dielectric material comprising: a first portion located at a surface of the dielectric, the first portion including tantalum oxide and tellurium; a second portion including tantalum oxide and covered by the first portion; a tellurium content in the first portion is higher than a tellurium content in the second portion; Dielectric.

[0039] (Technology 2) the first portion has a first layer shape; the second portion has a second layer shape; The thickness of the first portion is 24% or less of the sum of the thickness of the first portion and the thickness of the second portion. The dielectric material according to technique 1.

[0040] (Technology 3) In the first portion, a tellurium content at a first position a first distance away from the surface in a direction perpendicular to the surface is lower than a tellurium content at a second position a second distance away from the surface in the same direction that is shorter than the first distance. The dielectric material according to any one of claims 1 to 2.

[0041] (Technology 4) The tellurium contained in the first portion includes tetravalent tellurium. The dielectric material according to any one of claims 1 to 3.

[0042] (Technology 5) A first electrode; A second electrode; a dielectric film disposed between the first electrode and the second electrode; The dielectric film includes the dielectric material according to any one of techniques 1 to 4. Capacitor.

[0043] (Technology 6) the first electrode comprises tantalum metal; The second portion is located between the first electrode and the first portion. The capacitor according to technique 5.

[0044] (Technology 7) An electric circuit comprising the capacitor according to Technology 5 or 6.

[0045] (Technology 8) A circuit board comprising the capacitor according to Technology 5 or 6.

[0046] (Technology 9) A device comprising the capacitor according to Technology 5 or 6.

[0047] (Technology 10) contacting metallic tantalum with a solution containing tellurium; and anodizing the tantalum metal while the tantalum metal is in contact with the solution. A method for manufacturing a dielectric material. EXAMPLES

[0048] 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.

[0049] <Example 1> A tantalum plate having a thickness of 0.1 mm was prepared as an anode. This tantalum plate was rectangular with a short side of 10 mm and a long side of 50 mm in plan view. A tantalum foil having a surface area several times that of this tantalum plate was prepared as a cathode. The tantalum plate and the tantalum foil were ultrasonically cleaned in acetone for 10 minutes, and then washed with water. The tantalum plate and the tantalum foil were placed at a predetermined interval in an aqueous solution containing H6TeO6. The concentration of H6TeO6 in the aqueous solution was 1 mol / L. Next, a voltage was applied in a constant voltage state between the tantalum plate as the anode and the tantalum foil as the cathode using a power supply device, causing an electrochemical reaction on the surface of the tantalum plate, and anodization was performed. As a result, a dielectric film was formed on the tantalum plate. In the anodization, a DC stabilized power supply was used as the power supply device, and the current value during the formation of the dielectric film was measured with a digital multimeter. The voltage in the anodization was increased at a rate of 20 V / min, and after the voltage reached 80 V, it was kept at 80 V for 90 minutes. After the voltage was applied, the dielectric film formed on the tantalum plate was washed with running water for 15 minutes. In this way, the dielectric film according to Example 1 was obtained.

[0050] <Example 2> A dielectric film according to Example 2 was obtained in the same manner as in Example 1, except that the concentration of H6TeO6 in the aqueous solution was changed to 0.1 mol / L.

[0051] <Example 3> A dielectric film according to Example 3 was obtained in the same manner as in Example 1, except that the concentration of H6TeO6 in the aqueous solution was changed to 0.01 mol / L.

[0052] <Comparative Example 1> Except for using an aqueous solution containing H3PO4 instead of the aqueous solution containing H6TeO6, a dielectric film according to Comparative Example 1 was obtained in the same manner as in Example 1. The concentration of H3PO4 in this aqueous solution was 0.0017 mol / L.

[0053] (Elemental composition analysis) XPS measurement was performed to analyze the composition of the dielectric film according to each example using an XPS measurement device PHI 5000 VersaProbe manufactured by ULVAC-PHI. In this measurement, MgKα radiation (1253.6 eV) was used as the characteristic X-ray. FIG. 5 is a graph showing the results of the XPS measurement of the dielectric film according to Example 2. In FIG. 5, the vertical axis represents the intensity of photoelectrons, and the horizontal axis represents the binding energy. In FIG. 5, fitting of the measurement data was performed by the least squares method, and the peak position (578.6 eV) of the graph shown in FIG. 5 was identified. Since this peak position is close to the peak position of TeO2, it is considered that the oxidation number of tellurium contained in the dielectric film according to Example 2 is tetravalent, which is 2 less than the highest oxidation number of hexavalent. It is to be noted that the oxidation number of tellurium contained in these dielectric films was also estimated to be tetravalent from the results of the XPS measurement of the dielectric films according to Examples 1 and 3.

[0054] (Composition analysis in the depth direction) A TOF-SIMS apparatus TOF.SIMS5 manufactured by ION-TOF was used to perform composition analysis of the dielectric film according to each example. In the TOF-SIMS, Bi accelerated at a voltage of 30 kV was used as an ion beam. 3+ The sputtering ion species used was Cs + The depth was determined based on the sputtering rate. Figures 6A, 6B, and 6C show tellurium oxide ions (TeO - ), tantalum oxide ion (TaO 3- ), and oxygen ions (O -6D and 6E are graphs showing the relationship between the signal intensity of tellurium oxide ions (TeO - ), tantalum oxide ion (TaO 3- ), and oxygen ions (O - 6A to 6E are graphs showing the relationship between the signal intensity of each ion in TOF-SIMS and the depth in the dielectric film. In Figures 6A to 6E, the vertical axis represents the signal intensity of each ion in TOF-SIMS, and the horizontal axis represents the depth in the dielectric film.

[0055] According to Figs. 6A to 6C, TaO 3- and O - The signal intensity is almost constant in the range of depth from 0 nm to about 160 nm, and it is understood that tantalum oxide is included in this range. - The signal intensity of TeO decreases with increasing depth in the range from 0 nm to a certain depth, and the certain depth is from about 32 nm to about 38 nm. - The signal intensity of is extremely low in the range of depth of about 40 nm or more. Therefore, it is understood that the dielectric film containing tantalum oxide is formed to have a thickness of about 160 nm, and that tellurium is present in a first portion located between the surface of the dielectric film and a position at a predetermined depth from the surface, the first portion having a thickness of about 32 nm to about 38 nm, but that there is almost no tellurium present in other portions corresponding to the second portion.

[0056] In Fig. 6A to Fig. 6C, TaO 3- and O - The signal intensity is almost constant from 0 to 160 nm in depth, whereas the TeO - The signal intensity of decreases with increasing depth in the range corresponding to the first site, and becomes very low in the depth range of about 40 nm or more corresponding to the second site, which indicates that the tellurium content in the first site is higher than that in the second site.

[0057] In FIG. 6D and FIG. 6E, graphs a, b, and c show the TeO - 6D and 6E show the signal intensity of 1000 . It can be seen from Fig. 6D and Fig. 6E that, for example, by adjusting the concentration of H6TeO6 in the aqueous solution, it is possible to adjust the thickness of the portion of the dielectric film containing tellurium and the tellurium content in that portion.

[0058] (Dielectric properties) AC impedance measurements were performed using the tantalum plates on which the dielectric films of each of the Examples and Comparative Example 1 were formed. The measurements were performed in a phosphoric acid aqueous solution with a concentration of 1 mol / L using a potentiostat and a galvanostat. The voltage amplitude was adjusted to 100 mV, and an AC voltage was applied between a pair of electrodes including the tantalum plate in the range of 0.1 Hz to 1 MHz. The capacitance of the capacitor with the dielectric film was calculated based on the AC impedance measurement results. The AC impedance measurements were performed in a room temperature environment.

[0059] FIG. 7A is a graph showing the relationship between the capacitance and frequency of the capacitors having the dielectric films according to Example 1 and Comparative Example 1. FIG. 7B is a graph showing the relationship between the capacitance and frequency of the capacitors having the dielectric films according to Example 2 and Comparative Example 1. FIG. 7C is a graph showing the relationship between the capacitance and frequency of the capacitors having the dielectric films according to Example 3 and Comparative Example 1. In FIGS. 7A to 7C, the vertical axis indicates the capacitance, and the horizontal axis indicates the frequency of the AC voltage. As shown in FIGS. 7A to 7C, the capacitance of the capacitors having the dielectric films according to Examples 1, 2, and 3 was larger than the capacitance of the capacitor having the dielectric film according to Comparative Example 1. Thus, it was suggested that the inclusion of tellurium in the surface portion of the dielectric containing tantalum oxide is advantageous in increasing the capacitance of the capacitor. As described above, it is considered that the oxidation number of tellurium contained in the dielectric is 4, so that structural asymmetry occurs and polarization is easily generated, which is thought to contribute to the realization of high capacitance. [Industrial Applicability]

[0060] The dielectric material according to the present disclosure can be used in electronic components such as capacitors. [Explanation of symbols]

[0061] 1 Dielectric 1a surface 2 Base material 3a, 3b Capacitor 4 Electrical Circuits 5 Circuit Board 7 Equipment 10 Dielectric film 11 First part 11a First layer 12 Second part 12a Second layer 15 Porous materials 15p hole 21 First electrode 22 Second electrode

Claims

1. A dielectric material comprising: a first portion located at a surface of the dielectric, the first portion including tantalum oxide and tellurium; a second portion including tantalum oxide and covered by the first portion; a tellurium content in the first portion is higher than a tellurium content in the second portion; Dielectric.

2. the first portion has a first layer shape; the second portion has a second layer shape; The thickness of the first portion is 24% or less of the sum of the thickness of the first portion and the thickness of the second portion. The dielectric material according to claim 1 .

3. In the first portion, a tellurium content at a first position a first distance away from the surface in a direction perpendicular to the surface is lower than a tellurium content at a second position a second distance away from the surface in the same direction that is shorter than the first distance. The dielectric material according to claim 1 .

4. The tellurium contained in the first portion includes tetravalent tellurium. The dielectric material according to claim 1 .

5. A first electrode; A second electrode; a dielectric film disposed between the first electrode and the second electrode; The dielectric film comprises the dielectric material according to any one of claims 1 to 4. Capacitor.

6. the first electrode comprises tantalum metal; The second portion is located between the first electrode and the first portion. The capacitor of claim 5 .

7. A capacitor comprising the capacitor according to claim 5 . Electrical circuit.

8. A capacitor comprising the capacitor according to claim 5 . Circuit board.

9. A capacitor comprising the capacitor according to claim 5 . device.

10. contacting metallic tantalum with a solution containing tellurium; and anodizing the tantalum metal while the tantalum metal is in contact with the solution. A method for manufacturing a dielectric material.

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