Tantalum capacitor

Abstract

The present disclosure provides a tantalum capacitor including: a tantalum body including a tantalum element including tantalum particles, a conductive polymer layer disposed on the tantalum element, and a tantalum wire penetrating a portion of each of the tantalum element and the conductive polymer layer in a first direction; a molded portion including fifth and sixth surfaces opposite to each other in the first direction, third and fourth surfaces opposite to each other in the second direction, and first and second surfaces opposite to each other in the third direction, and surrounding the tantalum body; a first coating disposed on at least a portion of an interface between the tantalum body and the molded portion; and a second coating layer disposed on the first coating layer, in which the second coating layer is thicker than the first coating layer.

Description

[0001] This application claims the benefit of priority to Korean Patent Application No. 10-2023-0167128, filed with the Korean Intellectual Property Office on November 27, 2023, the disclosure of which is hereby incorporated by reference in its entirety. Technical Field

[0002] The present disclosure relates to a tantalum capacitor, and more particularly, to a tantalum capacitor having improved stress resistance reliability and moisture resistance. Background Art

[0003] Tantalum (Ta) is a metal that is widely used in various industries, including the electrical and electronics industries, mechanical engineering industries, chemical engineering industries, medical industries, and aerospace and defense industries, due to its mechanical and physical properties, such as a high melting point and excellent ductility and corrosion resistance.

[0004] In particular, due to the property that tantalum forms the most stable anodic oxide film among all metals, tantalum is currently widely used as an anode material for small capacitors.

[0005] In addition, due to the recent rapid development of the information technology (IT) industry, such as the electronics industry and the information and communication industry, the use of tantalum materials has been increasing rapidly every year.

[0006] A tantalum capacitor has a structure in which a tantalum body is connected to an electrode using an internal lead frame. Here, if sufficient adhesion between the internal lead frame and the molding part cannot be ensured, interface defects may occur, and moisture may penetrate through the corresponding interface. This may deteriorate the characteristics of the tantalum capacitor in a high-temperature and high-humidity environment and affect reliability. Summary of the Invention

[0007] One aspect of the present disclosure is to provide a tantalum capacitor having excellent reliability by enhancing the interface to reduce the moisture absorption rate.

[0008] Another aspect of the present disclosure is to provide a tantalum capacitor having enhanced stress resistance characteristics.

[0009] According to one aspect of the present disclosure, a tantalum capacitor includes: a tantalum body including a tantalum element, a conductive polymer layer, and a tantalum wire, the tantalum element including tantalum particles, the conductive polymer layer disposed on the tantalum element, and the tantalum wire penetrating through a part of each of the tantalum element and the conductive polymer layer in a first direction; a molding portion including a fifth surface and a sixth surface opposite to each other in the first direction, a third surface and a fourth surface opposite to each other in a second direction, and a first surface and a second surface opposite to each other in a third direction, the molding portion surrounding the tantalum body; a first coating disposed on at least a part of a first interface between the tantalum body and the molding portion; and a second coating disposed on the first coating, wherein the second coating is thicker than the first coating.

[0010] According to another aspect of the present disclosure, a tantalum capacitor includes: a tantalum body including a tantalum element, a conductive polymer layer, and a tantalum wire, the tantalum element including tantalum particles, the conductive polymer layer disposed on the tantalum element, and the tantalum wire penetrating through a part of each of the tantalum element and the conductive polymer layer in a first direction; a molding portion including a fifth surface and a sixth surface opposite to each other in the first direction, a third surface and a fourth surface opposite to each other in a second direction, and a first surface and a second surface opposite to each other in a third direction, the molding portion surrounding the tantalum body; an anode lead frame extending to the second surface of the molding portion and electrically connected to the tantalum wire; a cathode lead frame spaced apart from the anode lead frame and extending to the second surface of the molding portion; a first coating disposed on at least a part of at least one of a second interface between the molding portion and the anode lead frame and a third interface between the molding portion and the cathode lead frame; and a second coating disposed on the first coating. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The above and other aspects, features, and advantages of the present disclosure will be more clearly understood by combining the drawings and the following detailed description. In the drawings: Figure 1 is a perspective view of a tantalum capacitor according to the present disclosure; Figure 2 is a side view of a tantalum capacitor according to the present disclosure; Figure 3 is along Figure 1 sectional view taken along line I-I' in Figure 4 is Figure 3 an enlarged view of part A in Figure 5 is a sectional view taken along line I-I' of a tantalum capacitor according to a variant example of the present disclosure; Figure 6 isFigure 5 An enlarged view of part B in; and Figure 7 is a cross-sectional view of a tantalum capacitor in the prior art. Detailed Description

[0012] Exemplary embodiments of the present disclosure may be illustrated in many different forms and should not be construed as limited to the specific embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the inventive concept to those skilled in the art. In the drawings, the shapes and sizes of elements may be exaggerated for clarity.

[0013] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings.

[0014] In the drawings, the X direction may be defined as the first direction or the length direction, the Y direction may be defined as the second direction or the width direction, and the Z direction may be defined as the third direction or the thickness direction.

[0015] Figure 1 is a perspective view of a tantalum capacitor according to the present disclosure. Figure 2 is a side view of a tantalum capacitor according to the present disclosure. For ease of description, in Figure 1 and Figure 2 the first coating 510 and the second coating 520 are omitted to show the internal structure.

[0016] Referring to Figure 1 and Figure 2 , the tantalum capacitor 1000 according to this exemplary embodiment may include a tantalum body 100 and a molding part 200, and may further include an anode lead frame 300 and a cathode lead frame 400.

[0017] The tantalum body 100 may have a tantalum wire 150 exposed in the first direction (X direction). Here, the tantalum wire 150 may penetrate a part of the tantalum element 110 (to be described later) in the first direction (X direction). Before the mixture of tantalum powder and binder is pressed, the tantalum wire 150 may be inserted into the mixture of tantalum powder and binder so as to be installed such that the tantalum wire 150 deviates from the center of the mixture. That is, the tantalum body 100 may be formed by inserting the tantalum wire 150 into the mixture of tantalum powder and binder and then sintering in a high-temperature and high-vacuum (10 -5 Torr or lower) atmosphere for about 30 minutes to be molded into a tantalum body of a desired size. In the present disclosure, the term "powder" may include the meanings of powdery and granular.

[0018] The molding part 200 can cover the tantalum body 100 and can be formed such that one surface of the first connection part 320 of the anode lead frame 300 and one surface of the cathode lead frame 400 are exposed. The molding part 200 can include a first surface 1 and a second surface 2 that face each other in the third direction, a third surface 3 and a fourth surface 4 that face each other in the second direction, and a fifth surface 5 and a sixth surface 6 that face each other in the first direction.

[0019] The molding part 200 of the tantalum capacitor 1000 according to the present disclosure can be formed by transfer molding a resin (such as an epoxy molding compound (EMC)) so that the resin surrounds the tantalum body 100. The molding part 200 is used to protect the tantalum wire 150 and the tantalum body 100 from external influences.

[0020] The anode lead frame 300 can be electrically connected to the tantalum wire 150 and can be used as a terminal when the tantalum capacitor 1000 is mounted on a substrate. The anode lead frame 300 can include a first connection part 320 and a first bending part 310, and the first bending part 310 can be inclined toward the tantalum body 100 with respect to the first connection part 320. The first connection part 320 of the anode lead frame 300 can be exposed on the second surface 2 of the molding part 200. The first connection part 320 can be exposed on the lower surface of the molding part 200 and can be used as a terminal when the tantalum capacitor 1000 is mounted on a substrate. Here, the first connection part 320 can be spaced apart from the tantalum body 100 and can be used as the anode of the tantalum capacitor 1000 according to the present disclosure. To this end, the anode lead frame 300 can be formed of a conductive metal (such as a nickel / iron alloy).

[0021] The cathode lead frame 400 can be connected to the tantalum body 100 and can be used as a terminal when the tantalum capacitor 1000 is mounted on a substrate. The cathode lead frame 400 can be arranged to be spaced apart from the anode lead frame 300 and extend along the first direction (X direction). The cathode lead frame 400 can be exposed on the second surface 2 of the molding part 200. The cathode lead frame 400 can be exposed on the lower surface of the molding part 200 and can be used as a terminal when the tantalum capacitor 1000 is mounted on a substrate, and can be used as the cathode of the tantalum capacitor 1000 according to the present disclosure. To this end, the cathode lead frame 400 can be formed of a conductive metal (such as a nickel / iron alloy).

[0022] In addition, although not shown in the drawings, the tantalum capacitor according to an exemplary embodiment in the present disclosure may further include a conductive adhesive layer to bond the cathode lead frame 400 to the tantalum body 100. Such a conductive adhesive layer can be formed, for example, by coating a certain amount of a conductive adhesive (including an epoxy-based thermosetting resin and conductive metal powder (such as silver (Ag) powder)) and curing it, but the present disclosure is not limited thereto.

[0023] Figure 3is taken along Figure 1 the line I-I' in Figure 4 and is Figure 3 an enlarged view of part A of

[0024] Referring to Figure 3 and Figure 4 , the tantalum body 100 of the tantalum capacitor 1000 according to an exemplary embodiment in the present disclosure includes: a tantalum element 110 containing tantalum powder or tantalum granules; a conductive polymer layer 120 disposed on the tantalum element 110; a carbon layer 130 disposed on the conductive polymer layer 120; and a silver (Ag) layer 140 disposed on the carbon layer 130.

[0025] The tantalum capacitor may further include a tantalum wire 150 having an insertion region inside the tantalum element 110 and a non-insertion region outside the tantalum element 110. The tantalum wire 150 may penetrate through a part of each of the tantalum element 110 and the conductive polymer layer 120 in a first direction.

[0026] The tantalum element 110 may be formed by sintering a molded body including a metal powder (e.g., tantalum (Ta) powder) and a binder.

[0027] Specifically, the tantalum element 110 may be manufactured by mixing a metal powder, a binder, and a solvent in a specific ratio, stirring the mixture, pressing the mixture to form a rectangular hexahedron (e.g., a cuboid), and then sintering the obtained rectangular hexahedron at a high temperature and high vibration.

[0028] The metal powder is not particularly limited as long as it can be used in the tantalum element 110 of the tantalum capacitor 1000 according to an exemplary embodiment in the present disclosure, and it may be tantalum (Ta) powder. However, the present disclosure is not limited thereto, and the metal powder may be one or more selected from the group consisting of aluminum (Al), niobium (Nb), vanadium (V), titanium (Ti), and zirconium (Zr). Therefore, aluminum element, niobium element, etc. may be used instead of the tantalum element. Additionally, when the metal powder is tantalum (Ta) powder, the tantalum element in the finished tantalum capacitor includes tantalum granules.

[0029] The binder is not particularly limited and may be, for example, a cellulose-based binder.

[0030] The cellulose-based binder may be one or more selected from the group consisting of nitrocellulose, methylcellulose, ethylcellulose, and hydroxypropylcellulose.

[0031] Furthermore, the tantalum wire 150 may be inserted and installed to deviate from the center of the mixture before pressing the mixture.

[0032] According to an exemplary embodiment in the present disclosure, a dielectric oxide layer may be formed on the tantalum element 110 as an insulating layer. That is, the dielectric oxide layer may be formed by growing an oxide film (e.g., Ta 2 O 5 ) on the surface of the tantalum element 110 through a chemical process using an electrochemical reaction. Here, the dielectric oxide layer turns the tantalum element 110 into a dielectric. In addition, a conductive polymer layer 120 having a negative polarity may be coated and formed on the dielectric oxide layer.

[0033] The conductive polymer layer 120 is not particularly limited and may include, for example, a conductive polymer.

[0034] Specifically, the conductive polymer may be formed by chemical polymerization or electrolytic polymerization using 3,4-ethylenedioxythiophene (EDOT), pyrrole monomer, or polypyrrole, and then may be formed as a cathode layer having the conductive polymer on the outer surface (formed as an insulating layer) of the tantalum element 110.

[0035] That is, the conductive polymer layer 120 may be formed using a polymer slurry, and the polymer slurry may include at least one of polypyrrole, polyaniline, and EDOT (3,4-ethylenedioxythiophene). In addition, the conductive polymer layer 120 may include poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). PEDOT:PSS may be produced by oxidative polymerization of EDOT using poly(styrenesulfonate) (PSS) as a template for charge balancing.

[0036] In addition, a carbon layer 130 is stacked on the conductive polymer layer 120. For example, the carbon layer may be stacked by dissolving carbon powder in an organic solvent including an epoxy resin, dipping the tantalum element 110 in the solution in which the carbon powder is dissolved, and then drying the tantalum element 110 at a specific temperature to volatilize the organic solvent.

[0037] In addition, the carbon layer 130 can be used to prevent silver (Ag) ions from passing through.

[0038] Next, a silver (Ag) layer 140 formed using silver (Ag) paste may be formed on the surface of the carbon layer 130.

[0039] The silver (Ag) layer 140 may be stacked on the outside of the carbon layer 130 to improve conductivity.

[0040] In addition, the silver (Ag) layer 140 can improve the conductivity of the polarity of the cathode layer, thereby promoting electrical connection for polarity transfer.

[0041] Figure 7 is a cross-sectional view of a prior art tantalum capacitor.

[0042] Tantalum capacitors without a coating in the prior art have the problem that sufficient adhesion between the lead frame (or tantalum body) and the molding part cannot be ensured, resulting in interface defects (for example, making the interface have openings or making the interface open). In a high-temperature and high-humidity environment, moisture (for example, water vapor) may penetrate into the capacitor through the open interface (hereinafter referred to as the moisture absorption defect), thereby deteriorating the reliability of the tantalum capacitor.

[0043] The tantalum capacitor 1000 according to the present disclosure includes a first coating 510 and a second coating 520.

[0044] Referring to Figure 3 and Figure 4 , the first coating 510 may be provided on at least a part of the interface (for example, the first interface) between the tantalum body 100 and the molding part 200. Herein, the "interface" may refer to both the surfaces of two elements in contact with each other and the surfaces of two elements opposite to each other and combined together through other elements.

[0045] In addition, the first coating 510 may be provided on at least a part of at least one of the interfaces (for example, the second interface) between the molding part 200 and the anode lead frame 300 and the interface (for example, the third interface) between the molding part 200 and the cathode lead frame 400.

[0046] The first coating 510 can be used to enhance the interface between the tantalum body 100 and the molding part 200 and / or between the lead frames 300 and 400 and the molding part 200. In other words, sufficient interfacial bonding force can be ensured to prevent moisture absorption defects.

[0047] The first coating 510 may extend to the second surface 2 of the molding part 200. When the lead frames 300 and 400 extend to the second surface 2 of the molding part 200, the interface between the second surface 2 of the molding part 200 and the lead frames 300 and 400 may have a structure vulnerable to the penetration of external moisture (for example, water vapor). As in the present disclosure, since the first coating 510 extends to the second surface 2 of the molding part 200, the penetration of external moisture (for example, water vapor) can be fundamentally blocked.

[0048] The first coating 510 may have a thickness t1 greater than 0 μm and less than or equal to 1 μm. Specifically, if the thickness of the first coating 510 exceeds 1 μm, cracking of the coating may occur and moisture penetration through the interface may be promoted.

[0049] The first coating 510 may include a polyfunctional alkoxysilane. Alkoxysilane has hydrophobicity, so it can prevent moisture penetration and contamination, and can improve the mechanical strength against bending stress through a curing reaction.

[0050] As an example, the first coating 510 may include a silane coupling agent. In this case, one end of the silicon (Si) atom of the first coating 510 may be covalently bonded or hydrogen-bonded to the molding part 200 and the lead frames 300 and 400, and the other end of the silicon (Si) atom may be bonded to a hydrophobic functional group.

[0051] Specifically, the silane coupling agent may have two functional groups with different reactivities (i.e., a hydrophilic group and a hydrophobic group) in one molecule, and may be represented by the following [Chemical Formula 1].

[0052] [Chemical Formula 1] X 3-n Me n Si-Q-Y (n = 0, 1).

[0053] Here, X is a functional group that is chemically bonded to an inorganic material, and for example, may be an alkoxy group (R-O) having an alkyl group (R) including 1 to 16 carbon atoms, such as a methoxy group (CH 3 O-) or an ethoxy group (C 2 H 5 O-). X may be a hydrolyzable hydrophilic functional group.

[0054] Me may be a methyl group, and Q may be an ethylene group or a propylene group, but is not limited thereto.

[0055] Y is a functional group that is chemically bonded to an organic material, and may be formed using, for example, an amino group (-NH 2 ), a vinyl group (CH 2 CH-), an acrylic group, a methacryloyl group, an isocyanate group (-N=C=O), a mercapto group (SH-), a ureido group (-NHCONH 2 ), an epoxy group, etc., but is not limited thereto. Y may be a non-hydrolyzable hydrophobic functional group.

[0056] More specifically, the first coating 510 may include an aminosilane-based material. Specific examples may include, but are not limited to, aminopropyltrimethoxysilane (APTMS) and N-aminoethylaminopropyltrimethoxysilane (AEAPS). For example, the first coating 510 may include a polyfunctional alkoxysilane, and the polyfunctional alkoxysilane may include aminopropyltrimethoxysilane (APTMS) and / or N-aminoethylaminopropyltrimethoxysilane (AEAPS). In the case of the aminosilane-based material, the phenomenon of ammonium ions (NH 4+ ) being generated by the amino group may strongly occur at a pH of about 10, and due to the condensation reaction, the growth of polysiloxane in the second coating 520 may be promoted (which will be described below).

[0057] The second coating 520 is disposed on the first coating 510. Specifically, the second coating 520 may be formed along the first coating 510 at the aforementioned interface.

[0058] The tantalum capacitor 1000 according to the present disclosure can further improve the moisture resistance reliability by disposing the second coating 520 on the first coating 510. In addition, when the tantalum body 100 expands due to moisture penetration, internal stress is likely to occur. Here, the elastic second coating 520 can be disposed between the tantalum body 100 and the molding portion 200 so that the tantalum capacitor 1000 has enhanced characteristics of resisting internal stress.

[0059] That is, the second coating 520 is used to release the stress occurring at the interfaces between the tantalum body 100 and the molding portion 200 and / or between the lead frames 300 and 400 and the molding portion 200. Since the second coating 520 serves as a buffer portion to absorb the stress at the interface, the second coating 520 is formed to be thicker than the first coating 510 described above.

[0060] The second coating 520 may have a thickness t2 greater than 10 μm and less than or equal to 50 μm. If the thickness of the second coating 520 exceeds 50 μm, the coating may be exposed to the outside of the chip (as will be described below), thus increasing the probability of defect occurrence.

[0061] The second coating 520 may include polysiloxane. As a specific example, the second coating 520 may include polydimethylsiloxane, polymethylhydrosiloxane, polymethylphenylsiloxane, and polydiphenylsiloxane, but is not limited thereto.

[0062] Polysiloxane is a material having a low storage modulus and good recovery characteristics at room temperature. Specifically, when the second coating 520 is formed using the aforementioned polysiloxane, the second coating 520 may have a storage modulus value (range) as shown in the following [Table 1] according to the temperature.

[0063] [Table 1]

[0064] When the second coating 520 has a storage modulus value within the range shown in [Table 1], a high stress reduction effect can be obtained. However, the present disclosure is not limited to these storage modulus values.

[0065] The coating 500 can be formed on the semi-finished tantalum capacitor by dipping, spraying, jetting, or deposition, but is not limited thereto. Here, the semi-finished state may refer to the state of the tantalum capacitor before forming the molding portion 200 for forming its outer shape.

[0066] In the tantalum capacitor according to the present disclosure, a plurality of coatings 500 can be arranged in the manner described above to enhance the interface between the lead frame (or tantalum body) and the molding portion, thereby reducing the moisture absorption rate and thus ensuring reliability. In addition, by forming the coating using a material having excellent elasticity, the tantalum capacitor can obtain enhanced characteristics of resisting internal stress (which is generated when internal components expand due to moisture penetration).

[0067] The thickness of each of the first coating, the second coating, and the third coating (the third coating will be described later with reference to Figure 5 can refer to the average thickness, and the average thickness can be obtained in the following manner. The surface of the tantalum capacitor in the first direction (X direction) - the third direction (Z direction) is polished in the second direction (W direction) to about 1 / 2 of the depth of the tantalum capacitor to obtain a cross-sectional sample as shown in Figure 3 and Figure 5 . The thickness and arrangement of the first coating, the second coating, and the third coating at the interface between the relevant part in the tantalum capacitor and the molding portion can be checked by observing the obtained cross-sectional sample with a scanning electron microscope (SEM) at a magnification of 500 to 20000. In the cross-sectional sample as shown in Figure 4 and Figure 6 , the average thickness can be obtained by measuring the thickness (t1 or t2 or t3) of the coating in the third direction (Z direction) at five points and calculating the arithmetic mean of the thicknesses at the five points. Even if not described in the present disclosure, other methods and / or other tools understood by those of ordinary skill in the art can be used.

[0068] Figure 5 is a cross-sectional view taken along line I-I' of a tantalum capacitor according to a variant example of the present disclosure. Figure 6 is Figure 5 an enlarged view of part B in

[0069] The tantalum capacitor 1000' according to a variant example of the present disclosure may further include a third coating 530. The third coating 530 may be provided on the second coating 520.

[0070] The third coating 530 may include a material having low moisture permeability, which can further improve the moisture resistance reliability of the tantalum capacitor. Specifically, the third coating 530 may include polysiloxane and / or polyimide. The water vapor transmission rate (WVTR) of the third coating 530 may be 1.3 g / (m 2 × day) or less.

[0071] The third coating 530 may have a thickness t3 greater than 1 μm and less than or equal to 20 μm. The third coating 530 can ensure sufficient moisture resistance reliability within the range of greater than 1 μm and less than or equal to 20 μm and can prevent external defects of the coating.

[0072] The sum of the thicknesses of the first coating 510, the second coating 520, and the third coating 530 may be less than or equal to 60 μm. If the sum of the thicknesses exceeds 60 μm, the coating may be exposed to the outside of the chip, thereby increasing the possibility of defect occurrence.

[0073] The description of the components other than the third coating 530 is redundant, and thus this description is omitted here.

[0074] One effect of the present disclosure is to provide a tantalum capacitor having excellent reliability by enhancing an interface to reduce a moisture absorption rate.

[0075] Another effect of the present disclosure is to provide a tantalum capacitor having enhanced stress resistance characteristics.

[0076] Although the exemplary embodiments have been shown and described above, it will be readily understood by those skilled in the art that modifications and variations can be made without departing from the scope of the present disclosure defined by the appended claims.

Claims

1. A tantalum capacitor, comprising: a tantalum body comprising a tantalum element, a conductive polymer layer, and a tantalum wire, the tantalum element comprising tantalum particles, the conductive polymer layer being disposed on the tantalum element, the tantalum wire penetrating a portion of each of the tantalum element and the conductive polymer layer in a first direction; a molded portion including a fifth surface and a sixth surface opposite to each other in the first direction, a third surface and a fourth surface opposite to each other in the second direction, and a first surface and a second surface opposite to each other in the third direction, the molded portion surrounding the tantalum body; a first coating disposed on at least a portion of a first interface between the tantalum body and the molding portion; as well as a second coating layer disposed on the first coating layer, Wherein, the second coating layer is thicker than the first coating layer.

2. The tantalum capacitor according to claim 1, wherein: The first coating layer includes a multifunctional alkoxysilane.

3. The tantalum capacitor according to claim 1, wherein: The second coating includes polysiloxane.

4. The tantalum capacitor according to claim 1, wherein: The first coating layer has a thickness greater than 0 μm and less than or equal to 1 μm.

5. The tantalum capacitor according to claim 1, wherein The second coating layer has a thickness greater than 10 μm and less than or equal to 50 μm.

6. The tantalum capacitor according to claim 1, wherein: The second coating layer is located on the surface of the first coating layer. 7 . The tantalum capacitor of claim 1 , further comprising a third coating layer disposed on the second coating layer.

8. The tantalum capacitor according to claim 7, wherein: The third coating layer includes polyimide.

9. The tantalum capacitor according to claim 7, wherein: The third coating layer has a thickness greater than 1 μm and less than or equal to 20 μm.

10. The tantalum capacitor according to claim 7, wherein: The sum of the thicknesses of the first coating layer, the second coating layer and the third coating layer is less than or equal to 60 μm.

11. The tantalum capacitor according to claim 1, wherein: The tantalum body further comprises: a carbon layer disposed on the conductive polymer layer; and A silver layer is disposed on the carbon layer.

12. The tantalum capacitor according to claim 1, further comprising: an anode lead frame extending to the second surface of the molded portion and electrically connected to the tantalum wire; as well as A cathode lead frame is spaced apart from the anode lead frame and extends to the second surface of the molding portion.

13. The tantalum capacitor according to claim 12, wherein: The first coating is also disposed on at least a portion of a second interface between the molded portion and the anode lead frame, and / or The first coating layer is also disposed on at least a portion of a third interface between the molding portion and the cathode lead frame.

14. A tantalum capacitor, comprising: a tantalum body comprising a tantalum element, a conductive polymer layer, and a tantalum wire, the tantalum element comprising tantalum particles, the conductive polymer layer being disposed on the tantalum element, the tantalum wire penetrating a portion of each of the tantalum element and the conductive polymer layer in a first direction; a molded portion including a fifth surface and a sixth surface opposite to each other in the first direction, a third surface and a fourth surface opposite to each other in the second direction, and a first surface and a second surface opposite to each other in the third direction, the molded portion surrounding the tantalum body; an anode lead frame extending to the second surface of the molded portion and electrically connected to the tantalum wire; a cathode lead frame spaced apart from the anode lead frame and extending to the second surface of the molding portion; a first coating disposed on at least a portion of at least one of a second interface between the molding portion and the anode lead frame and a third interface between the molding portion and the cathode lead frame; as well as The second coating layer is disposed on the first coating layer.

15. The tantalum capacitor according to claim 14, wherein: The first coating layer includes a multifunctional alkoxysilane, and The second coating includes polysiloxane.

16. The tantalum capacitor according to claim 14, further comprising: a third coating layer, disposed on the second coating layer, Wherein, the third coating layer comprises polyimide.

17. The tantalum capacitor according to claim 14, wherein: The first coating layer extends to the second surface of the molded portion.

18. The tantalum capacitor according to claim 15, wherein: The second coating layer is thicker than the first coating layer.

19. The tantalum capacitor according to claim 15, wherein: The multifunctional alkoxysilane includes aminopropyltrimethoxysilane and / or N-aminoethylaminopropyltrimethoxysilane.

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