Patent Publication Number: US-2023135896-A1

Title: Tantalum capacitor

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     The present application claims the benefit of priority to Korean Patent Application No. 10-2021-0146405, filed on Oct. 29, 2021 in the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. 
     TECHNICAL FIELD 
     The present disclosure relates to a tantalum capacitor, and more particularly, to a tantalum capacitor having improved capacitance. 
     BACKGROUND 
     The slimming of set devices results in the miniaturization of components in the components industry. In addition, battery capacity has been increased as a size of a display device such as a smartphone, a tablet PC, or the like, is increased and high-specification application processors (APs) are applied, so that capacitors are required to have high capacity and miniaturization. 
     A tantalum (Ta) material is a metal that is widely used throughout various industries such as the electrical, electronic, mechanical, chemical, aerospace, and defense industries due to having mechanical and physical characteristics such as a high melting point, excellent ductility and excellent corrosion-resistance, or the like. In particular, since the tantalum material may form the most stable anodic oxide film, tantalum has been widely used as a material in forming anodes for small capacitors. Moreover, due to the rapid development of the IT industry, such as electronics and information and communication, the use of tantalum materials is increasing rapidly every year. 
     A tantalum capacitor according to the related art uses a structure, in which a terminal is led out to an external entity without an internal lead frame or a frame, to connect a tantalum material and an electrode to each other. 
     In this case, in the case of the structure using the internal lead frame, a space occupied by the tantalum material in the molded portion may be decreased by the lead frame constituting an anode and a cathode, and capacitance is in proportion to a volume of the tantalum material. In this case, capacitance may be limited. In the case of the structure in which a terminal is led out to an external entity without a frame, equivalent series resistance (ESR) of a capacitor is increased because a contact resistance is increased by a plurality of contact materials due to presence of the plurality of contact materials. 
     In addition, in the case of a structure according to the related art in which a terminal is led out to the outside without a frame, a cathode lead frame is disposed on a side surface of a product. Thus, capacitance may be deteriorated because an internal volume fraction of the tantalum material is reduced due to the need to secure a welding distance at which a solder is formed between the tantalum material and the cathode lead frame. 
     SUMMARY 
     An aspect of the present disclosure is to provide a tantalum capacitor which may implement high capacitance. 
     Another aspect of the present disclosure is to provide a tantalum capacitor having improved reliability by increasing mechanical strength. 
     Another aspect of the present disclosure is to provide a tantalum capacitor which may improve a breakdown voltage (BDV) by increasing a withstand voltage. 
     Another aspect of the present disclosure is to provide a tantalum capacitor which may prevent short-circuits caused by a contact between a terminal and a tantalum body. 
     Another aspect of the present disclosure is to provide a tantalum capacitor which may reduce equivalent series resistance (ESR). 
     According to an aspect of the present disclosure, a tantalum capacitor includes: a tantalum body including tantalum powder and having a tantalum wire exposed to one end surface of the tantalum body; a molded portion having two surfaces opposing each other in a first direction, two surfaces opposing each other in a second direction, and two direction opposing each other in a third direction, the two surfaces opposing in the third direction being first and second surfaces, the two surfaces opposing in the second direction being third and fourth surfaces, the two surfaces opposing in the first direction being fifth and sixth surfaces; an anode lead frame exposed to the second surface of the molded portion and electrically connected to the tantalum wire; and a cathode lead frame spaced apart from the anode lead frame and exposed to the second surface of the molded portion. The anode lead frame includes a first connection portion and a first bent portion, and the first bent portion forms an angle of inclination, ranging from 70° or more to 80° or less, with respect to the first connection portion, in which the first bent portion is inclined toward a side of the tantalum body. 
     According to another aspect of the present disclosure, a tantalum capacitor includes: a tantalum body including tantalum powder and having a tantalum wire exposed to one end surface of the tantalum body; a molded portion surrounding the tantalum body; an anode lead frame embedded in the molded portion and exposed to one surface of the molded portion; and a cathode lead frame spaced apart from the anode lead frame and exposed to the one surface of the molded portion. The anode lead frame includes a first connection portion exposed to the one surface of the molded portion and a first bent portion extending from the first connection portion to be connected to the tantalum wire in a slanted angle with respect to the first connection portion, and a portion of the first connection portion overlaps at least one portion of the tantalum body in a direction perpendicular to the one surface of the tantalum body. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The above and other aspects, features, and advantages of the present disclosure will be more clearly understood from the following detailed description, taken in conjunction with the accompanying drawings. 
         FIGS.  1  and  2    are perspective views of a tantalum capacitor according to an embodiment of the present disclosure, taken in different directions. 
         FIG.  3    is a side view of the tantalum capacitor of  FIG.  1   , taken in an I-direction. 
         FIG.  4    is a perspective view of a tantalum capacitor according to another embodiment of the present disclosure. 
         FIGS.  5  and  6    are side views of tantalum capacitors according to another embodiment and a modified embodiment of the present disclosure, respectively. 
         FIG.  7    is a perspective view of a tantalum capacitor according to another embodiment of the present disclosure. 
         FIG.  8    is a side view of a tantalum capacitor according to another embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, embodiments of the present disclosure will be described as follows with reference to the attached drawings. It is not intended to limit the techniques described herein to specific embodiments, and it should be understood to include various modifications, equivalents, and/or alternatives to the embodiments of the present disclosure. In connection with the description of the drawings, similar reference numerals may be used for similar components. 
     In the drawings, for clarity of description, parts irrelevant to the description may be omitted, and thicknesses of elements may be magnified to clearly represent layers and regions. Components having the same functions within a scope of the same idea may be described using the same reference numerals. 
     Hereinafter, exemplary embodiments of the present disclosure will be described with reference to accompanying drawings. 
     In the drawings, an X direction may be defined as a first direction, an L direction, or a length direction, a Y direction may be defined as a second direction, a W direction, or a width direction, and a Z direction defined as a third direction, a T direction, or a thickness direction. 
       FIGS.  1  and  2    are perspective views of a tantalum capacitor according to an embodiment, taken in different directions.  FIG.  3    is a side view of the tantalum capacitor of  FIG.  1   , taken in an I-direction. 
     Referring to  FIGS.  1  and  2   , a tantalum capacitor  1000  according to an exemplary embodiment may include a tantalum body  110  including tantalum powder and having a tantalum wire  111  exposed to one end surface, a molded portion  120  having fifth and sixth surfaces  5  and  6  opposing each other in a first direction, third and fourth surfaces  3  and  4  opposing each other in a second direction, and first and second surfaces  1  and  2  opposing each other in a third direction, and formed to surround the tantalum body  110 , an anode lead frame  130  exposed to the second surface  2  of the molded portion  120  and electrically connected to the tantalum wire  111 , and a cathode lead frame  140  spaced apart from the anode lead frame  130  and exposed to the second surface  2  of the molded portion  120 . 
     In this case, the anode lead frame  130  may include a first connection portion  132 , a first lead portion  133 , and a first bent portion  131 . The first bent portion  131  may extend from the first connection portion  132  to be connected to the tantalum wire  111  in a slanted angle with respect to the first connection portion  132 . The first bent portion  131  may have an angle of inclination within a range of 70° or more to 80° or less toward the tantalum body  110  with respect to the first connection portion  132 . 
     The tantalum body  110  may be formed of a tantalum material. As an example, the tantalum body  110  may be manufactured by mixing and stirring a metal powder and a binder at a predetermined ratio, compressing the mixed powder into a rectangular parallelepiped form, and sintering the compressed powder under high temperature and high vibration. 
     The tantalum body  110  may have a tantalum wire  111  exposed in an X direction of the body. The tantalum wire  111  may be inserted into a mixture of the tantalum powder and a binder to be off-centered within the body, before mixed powder of the tantalum powder and the binder is compressed. For example, the tantalum body  110  may be manufactured by molding a tantalum element in a desired size by inserting the tantalum wire  111  into the tantalum powder mixed with the binder and sintering the tantalum element at a high temperature under high vacuum (10 −5  torr or less) for about 30 minutes. 
     The anode lead frame  130  may be formed of a conductive metal such as a nickel/iron alloy, and may include a first connecting portion  132 , a first bent portion  131 , and a first lead portion  133  formed to be integrated with each other. 
     In an exemplary embodiment, the first connection portion  132  of the anode lead frame  130  may be exposed to the second surface  2  of the molded portion  120  to serve as a terminal when a board is mounted. In this case, the first connection portion  132  may be disposed to be spaced apart from the tantalum body  110 , and a space between the connection portion  132  and the tantalum body  110  spaced apart from each other may be filled with a resin component to be described later, or the like, constituting the molded portion  120 . 
     In an exemplary embodiment, the first lead portion  133  may refer to a portion, excluding the first connection portion  132  and the first bent portion  131 , in the anode lead frame  130 . In this case, the anode lead frame  130  may include a cut surface. A portion, which is bent with respect to the cut surface, and a portion, which is not bent with respect to the cut surface, may refer to the first bent portion  131  and the first lead portion  133 , respectively. The cut surface may be formed in a first direction, a second direction, and/or a third direction of the anode lead frame  130 . The tantalum capacitor  100  according to the exemplary embodiment of  FIG.  1    may have a structure in which an anode lead frame has a cut surface and a first lead portion is present. Alternatively, the tantalum capacitor  100  may have a structure, in which an anode lead frame does not have the cut surface, to be described later in  FIG.  7   . The structure, in which an anode lead frame does not have the cut surface, may refer to a structure in which only a first bent portion is present while a first lead portion is absent. 
     In an exemplary embodiment, the first bent portion  131  may form an angle of inclination “a” within a range of 70° or more to 80° or less toward the tantalum body  110  with respect to the first connection portion  132 . For example, a size of the acute angle “a” formed between the first connection portion  132  and the first bent portion  131  may be 70° or more to 80° or less. When the first bent portion  131  forms an angle of inclination “a” toward the tantalum body  110 , it may refer to a structure in which an end of the other side of the bending portion is directed toward the tantalum body in the first bent portion  131 . Referring to  FIGS.  1  to  3   , the angle of inclination “a” may refer to an angle between the first bent portion  131  and the first connection portion  132 . The angle of inclination “a” may be 80° or less, 79° or less, 78° or less, 77° or less, 76° or less, or 75° or less, but exemplary embodiments are not limited thereto. When the angle of inclination “a” between the first bent portion  131  and the first connection portion  132  satisfies the above range, sagging of the first bent portion  131 , caused by depression when the tantalum wire  111  is welded to the first bent portion  131 , may not occur. In addition, since the sagging of the first bent portion  131  may be significantly reduced as compared with the tantalum capacitor according to the related art in which an existing support portion is required, a shape of the first bent portion  131  may be maintained without a support portion. Meanwhile, when the angle of inclination “a” between the first bent portion  131  and the first connection portion  132  is outside of the above range, there is a high possibility that the tantalum wire  111  and/or the tantalum body  110  is exposed due to a change in positions of the tantalum body  110  and the tantalum wire  111 . For example, when the angle of inclination “a” is greater than 80°, the tantalum wire  111  may be outwardly exposed from the fifth surface  5  of the molded portion  120 , or the tantalum body  110  may be outwardly removed from the first surface  1  of the molded portion  120 . 
     In the present disclosure, the angle of inclination angle “a” may refer to an acute angle formed by the first bent portion  131  and the first connection portion  132 . In this case, since each of the first bent portion  131  and the first connection portion  132  has a three-dimensional shape having a width in the Y direction, the angle of inclination “a” may be an average value of angles measured in a plurality of regions having a width of the first bent portion  131  in a Y-direction, rather than an angle in one region. As an example, in a region in which the first bent portion  131  forms an acute angle with the first connection portion  132 , angles of ten points spaced apart from each other at regular intervals in a Y-direction (a width direction) may all be measured, and an average value of the measured angles may be designated as the angle of inclination “a”. Other measurement methods and/or tools appreciated by one of ordinary skill in the art, even if not described in the present disclosure, may also be used. 
     In the tantalum capacitor  100  according to an exemplary embodiment, the angle of inclination “a” between the first bent portion  131  and the first connection portion  132  may be in a range of 70° or more. The angle of inclination “a” may be 71° or more, 72° or more, 73° or more, 74° or more, or 75° or more, but exemplary embodiments are not limited thereto. When the angle of inclination “a” between the first bent portion  131  and the first connection portion  132  satisfies the above-mentioned range, mechanical reliability of a product may be improved while increasing capacity of the product. Meanwhile, when the angle of inclination “a” is outside of the above range, the tantalum body  110  and the first connection portion  132  of the anode lead frame  130  may be brought into contact with each other to cause short-circuits. 
     The above-described first bent portion  131  may be formed in a central portion of the anode lead frame  130  (see  FIGS.  1  to  8   ), but exemplary embodiments are not limited thereto. The first bent portion  131  may be formed on an external side of the anode lead frame  130  or on one side of the anode lead frame  130 , but exemplary embodiments are also not limited thereto. The first bent portion  131  may be bent at the anode lead frame  131  and may be transformed into various forms connected to the tantalum wire  111 , as a structure satisfying the above-described angle of inclination. 
     Table 1 illustrates an experimental example in which an angle of inclination “a” between the first bent portion  131  and the first connection portion  132  is different with respect to the tantalum capacitor  100  in which the tantalum body  110  having a length L of 7.3 mm, a width W of 4.3 mm, and a thickness T of 1.5 mm is applied to a molded portion  120  having a length L of 4.45 mm and a thickness of 1.1 mm. 
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE 1 
               
               
                   
               
               
                   
                 Bending 
                 Wire 
                 Exposure 
                   
                 Exposure 
               
               
                 Gradient 
                 Height 
                 Exposure 
                 Defect 
                 Short-circuits 
                 Defect 
               
               
                 (a) (°) 
                 (mm) 
                 (Top) 
                 (Bot) 
                 (High LC) 
                 (MK) 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 95 
                 0.67 
                 X 
                 ◯ 
                 X 
                 ◯ 
               
               
                 90 
                 0.67 
                 X 
                 ◯ 
                 ◯ 
                 ◯ 
               
               
                 85 
                 0.67 
                 X 
                 ◯ 
                 ◯ 
                 ◯ 
               
               
                 80 
                 0.65 
                 ◯ 
                 ◯ 
                 ◯ 
                 ◯ 
               
               
                 75 
                 0.64 
                 ◯ 
                 ◯ 
                 ◯ 
                 ◯ 
               
               
                 70 
                 0.63 
                 ◯ 
                 ◯ 
                 ◯ 
                 ◯ 
               
               
                 65 
                 0.61 
                 ◯ 
                 ◯ 
                 ◯ 
                 X 
               
               
                 60 
                 0.58 
                 ◯ 
                 X 
                 ◯ 
                 X 
               
               
                 55 
                 0.55 
                 ◯ 
                 X 
                 X 
                 X 
               
               
                   
               
            
           
         
       
     
     Referring to Table 1, when the angle of inclination “a” of the first bent portion  131  to the first connection portion  132  is less than 70°, the tantalum body  110  may be brought close to a side of the sixth surface  6  of the molded portion  120  during welding of the tantalum wire  111  and the first bent part  131 , so that the tantalum body  110  may be exposed outwardly of the molded portion  120 . 
     When an angle of the first bent portion  131  is greater than 80°, the tantalum wire  111  may be brought close to a side of the fifth surface  5  of the molded portion  120  during welding of the tantalum wire  111  and the first bent portion  131 , so that the tantalum wire  111  may be exposed outwardly of the molded portion  120 . 
     From Table 1, it can be seen that the angle of inclination “a” of the first bent portion  131  to the first connection portion  132  of the tantalum capacitor  100  may be adjusted to a predetermined range to provide a tantalum capacitor having capacitance significantly increased even in the same standard. Accordingly, characteristics of a tantalum capacitor, in which a withstand voltage is improved with an increase in volume of a sintered body even in the same size, may be significantly increased. In addition, a breakdown voltage (BDV) may be increased to improve reliability of a product. 
     Also, referring to Table 1, when the angle of inclination “a” the angle of inclination “a” of the first bent portion  131  to the first connection portion  132  is less than 60°, the tantalum body  110  may be brought close to the second surface  2  of the molded portion  120 , so that the tantalum body  110  may be exposed to the outside of the molded portion  120 . 
     Also, referring to Table 1, when the angle of inclination “a” between the first bent portion  131  and the first connection portion  132  is decreased to 55° or less or increased to 95° or more, the tantalum body  110  may be brought close to the first connection portion  132 , so that the tantalum body  110  and the first connection portion  132  of the anode lead frame  130  may be short-circuited. 
     From Table 1, it can be seen that the angle of inclination “a” of the first bent portion  131  to the first connection portion  132  may be adjusted to a predetermined range, so that a bending height of the first bent portion  131  may be adjusted to be constant. The first bent portion  131  having the bending height may effectively mitigate mechanical shock generated during welding due to a bent structure. 
     As described above, when the tantalum wire  111  is bonded to the first bent portion  131 , the first bent portion  131  may have a high angle of inclination to the second surface  2  of the molded portion  120  or the first connection portion  132 . Therefore, mechanical stress of the first connecting portion  132  may be improved in a third direction in which the first bent portion  131  receives a pressure from the tantalum wire  111  during welding. Accordingly, a configuration of the support portion supporting the first connection portion  132 , required in the tantalum capacitor according to the related art, may not be required, so that a volume of the tantalum body  110  may be increased to the extent to achieve high capacitance of the tantalum body  110 . 
     As described above, the first bent portion  131  may have a high angle of inclination “a” to the second surface  2  of the molded portion  120  or the first connection portion  132 . Therefore, assuming that the tantalum wire  111  has the same length, a length of the tantalum body  110  in the first direction X may be increased as compared with a conventional structure, which may also contribute to high capacitance of the tantalum body  110 . 
     In this case, the welding may be performed using, in detail, an electric spot-welding method, but exemplary embodiments are limited thereto. 
     In the tantalum capacitor  100  according to an exemplary embodiment, the molded portion  120  may be formed to expose one surface of the first connection portion  132  of the anode lead frame  130  and one surface of the second connection portion  142  of the cathode lead frame  140 . 
     The molded portion  120  of the tantalum capacitor according to the present disclosure may be formed by transfer-molding a resin such as an epoxy molding compound (EMC) to surround the tantalum body  110 . The molded portion  120  may serve to protect the tantalum wire  111  and the tantalum body  110  from the outside. 
     The first connection portion  132  may include first and second regions  132   a  and  132   b  having different thicknesses. Referring to the side view of  FIG.  3   , a thickness of the first region  132   a  of the first connection portion  132  may be smaller than a thickness of the second region  132   b  of the first connection portion  132 . Accordingly, a step may be formed between upper surfaces of the first and second regions  132   a  and  132   b . For example, as illustrated in  FIG.  3   , a recess or a reduced-thickness portion R may be formed on the first region  132   a  of the first connection portion  132 . On the other hand, the first region  132   a  of the first connector  132  may be closer to the tantalum body  110  than the second region  132   b  of the first connector  132 . For example, the first region  132   a  of the first connection portion  132  may be disclosed inside the second region  132   b  in the first direction X. When viewed in the third direction Z, at least a portion of the tantalum body  110  may overlap at least a portion of the first region  132   a  of the first connection portion  132 . 
     As the thickness of the first region  132   a  close to the tantalum body  110  of the first connection portion  132  is lower than the thickness of the second region  132   b , a distance between the tantalum body  110  and the first connection portion  132  spaced apart from each other may be increased to reduce a possibility that short-circuits occurs. In addition, the volume of the tantalum body  110  may be increased to that extent, which is advantageous in increasing the capacitance of the tantalum body  110  and the tantalum capacitor  100 . 
     The first lead portion  133 , as a configuration of the anode lead frame  130 , may be disposed to protrude outwardly of the molded portion  120 . The first lead portion  133  may refer to a region, divided from the above-described first connection portion  132  by a bent portion of the first bent portion  131  as a boundary, in the anode lead frame  130 . Referring to  FIGS.  1  and  2   , the anode lead frame  130  may include a first bent portion  131 , a first connection portion  132 , and a first lead portion  133 , and the first lead portion  133  may protrude outwardly of the molded portion  120 . As described in the present example, in the case in which the first lead portion  133  is disposed to protrude outwardly of the molded portion  120 , a bonding area of a solder may be increased when a substrate of the tantalum capacitor  100  is mounted, and thus, substrate fixing force may be improved. 
     The cathode lead frame  140  may be formed of a conductive metal such as a nickel/iron alloy, and may include a second bending portion  141 , a second connection portion  142 , and a second lead portion  143  formed to be integrated with each other. 
     The second connection portion  142  may be disposed to be spaced apart from each other in parallel to the first connection portion  132  of the anode lead frame  130  in the first direction X. The second connection portion  142  of the cathode lead frame  140  may be exposed to the second surface  2  of the molded portion  120 . The second connection portion  142  may be exposed to a lower surface of the molded portion  120  to serve as a terminal when the board is mounted. In this case, the second connection portion  142  may be in contact with the tantalum body  110  and may function as a cathode of the tantalum capacitor  100  according to the present disclosure. 
     In an exemplary embodiment, the second bending portion  141  may be vertically bent toward a side of the tantalum body  110 . Referring to  FIG.  2   , the cathode lead frame  140  may include a second bending portion  141 , a second connection portion  142 , and a second lead portion  143 , and the second bending portion  141  may bend toward the tantalum body  110 . Accordingly, mechanical strength of the tantalum capacitor according to the present disclosure may be significantly increased. 
     Referring to  FIG.  2   , the second bending portion  141  may be formed in a central portion of the cathode lead frame  140 , but exemplary embodiments are not limited thereto. The second bending portion  141  may be formed on an external side of the cathode lead frame  140  or formed on one side of the cathode lead frame  140 . In addition, the second bonding portion  141  may be transformed into various forms connected to the tantalum body  110 , as a structure bent at the cathode lead frame  140 . 
     In an exemplary embodiment, the second lead portion  143  may refer to a portion of the cathode lead frame  140  excluding the second connection portion  142  and the second bending portion  141 . In this case, the cathode lead frame  140  may include a cut surface. A portion, which is bent with respect to the cut surface, may refer to the second bending portion  141  and a portion, which is not bent with respect to the cut surface, may refer to the second lead portion  143 . The cut surface may be formed in the first direction X, the second direction Y, and/or the third direction Z of the cathode lead frame  140 . In the present specification, drawings are drawn based on a structure in which the cathode lead frame  140  has a cut surface and the second lead portion is present. In the present disclosure, the anode lead frame  130  or the cathode lead frame  140  may not have the cut surface. When the cathode lead frame  140  does not have the cut surface, it may refer to a structure in which only the second bending portion  141  and the second connection portion  142  are present and the second lead portion is absent. Such a structure may be a structure in which the connection portion is exposed to only the second surface  2  of the molded portion, and may be prevent short-circuits with other components and may be advantageous in increasing board mounting density. 
     Referring to  FIG.  2   , the second lead portion  143  of the cathode lead frame  140  may be disposed to protrude outwardly of the molded portion  120 . The second lead portion  143  may refer to a region, divided from the above-described second connection portion  142  by the bending portion of the second bending portion  141  as a boundary, in the cathode lead frame  140 . Referring to  FIG.  2   , the cathode lead frame  140  may include a second bending portion  141 , a second connection portion  142 , and a second lead portion  143 , and the second lead portion  143  may protrude outwardly of the molded portion  120 . As described in the present example, in the case in which the second lead portion  143  is disposed to protrude outwardly of the molded portion  120 , a bonding area of a solder may be increased when mounting a substrate of the tantalum capacitor according to the present disclosure, and thus, substrate fixing force may be improved. 
     When the cathode lead frame does not have an additional cut surface, the cathode lead frame may include a second bending portion and a second connection portion and may not include a second lead portion. In this case, the cathode lead frame may be exposed outwardly of the molded portion through only the second connection portion. 
     In the tantalum capacitor  100  according to an exemplary embodiment, an anode terminal may be formed on the first connection portion  132  and a cathode terminal may be formed on the second connection portion  142 . The anode terminal and/or the cathode terminal may include a conductive material, for example, one of a chromium-titanium intermetallic compound (Cr(Ti)), copper (Cu), nickel (Ni), palladium (Pd), gold (Au), or combinations thereof and may be formed by a sputter deposition method or a plating method. 
       FIG.  4    is a perspective view of a tantalum capacitor according to another embodiment. 
     Referring to  FIG.  4   , a tantalum capacitor  200  according to another embodiment may include a first connection portion  131  in which a groove  131   h  is formed, as compared with the tantalum capacitor  100  according to the embodiment. Therefore, a description will be provided for only the first connection portion  131  and the groove  131   h . Descriptions of the other configurations of the present embodiment may be substituted with those of an embodiment as it is. 
     In the case of the tantalum capacitor  200  according to another embodiment, an anode lead frame  130  may have a groove  131   h , formed in an end portion of a first bent portion  131 , through which a tantalum wire  111  is fitted. Referring to  FIG.  4   , the groove  131   h  may be disposed in an end portion of the first bent portion  131  of the anode lead frame  130 , and the tantalum wire  111  may be fitted into the groove  131   h  in the end portion of the first bent portion  131 . In this case, a surface on which the tantalum wire  111  and an end portion of the first bent portion  131  are in contact is described as having a U-shape, but exemplary embodiments are not limited thereto. As necessary, the surface may have a V-shape or a rectangular shape. 
     In the tantalum capacitor  200  according to another embodiment, a groove into which the tantalum wire  111  is fitted may be disposed in an end portion of the first bent portion  131  to increase a contact area between the first bent portion  131  and the tantalum wire  111 , so that an operation may be safely performed to prevent deterioration of electrical connectivity. A method of forming such a groove is not limited, and such a groove may be formed, for example, by punching or cutting a portion of the first bent portion  131 . 
     The other contents are substantially the same as those described in the tantalum capacitor  100  according to an embodiment, and a detailed description thereof will be omitted. 
       FIGS.  5  and  6    are side views of tantalum capacitors according to another embodiment and a modified embodiment of the present disclosure, respectively. 
     Referring to  FIGS.  5  and  6   , tantalum capacitors  300 A and  300 B according to another embodiment and a modified embodiment may include an anode lead frame  130  further including a bending portion  134  disposed on an end of a first bent portion  131 , as compared with the tantalum capacitor according to an embodiment. Therefore, a description will be provided for only the bending portion  134  and a groove  134   h  formed in the bending portion  134 . Descriptions of the other configurations of the present embodiment may be substituted with those of an embodiment as it is. 
     In the tantalum capacitor  300 A according to another embodiment, the anode lead frame  130  may include a bending portion  134  on an end of the first bent portion  131 , and the bending portion  134  may be connected to a tantalum wire  111 .  FIG.  5    is a diagram illustrating a tantalum capacitor  300 A according to another embodiment in which a bending portion  134  is disposed on an end of the first bent portion  131  and the bending portion  134  is in contact with and connected to a lower surface of the tantalum wire  111 . In this case, the bending portion  134  may be bent toward a lower end of the tantalum wire  111 , and the upper surface  134   a  of the bending portion  134  may be connected to the lower surface of the tantalum wire  111 . 
     In the case of the tantalum capacitor  300 A according to another embodiment, a groove  134   h  may be disposed in the bending portion  134 . The tantalum wire  111  may be in contact with the bending portion  134  through the groove  134   h  of the bending portion  134 . In this case, the bending portion  134  may be bent toward the tantalum wire  111 , and at least a portion of the tantalum wire  111  may be disposed in the groove  134   h  of the bending portion  134  to be in contact with and connected to the bending portion  134 . 
       FIG.  6    is a diagram illustrating an example of a modified example  300 B of the tantalum capacitor of  FIG.  5   . Referring to  FIG.  6   , a bending portion  134  may be disposed on an end of the first bent portion  131 , and the tantalum wire  111  may be in contact with the bending portion  134 . In this case, the bending portion  134  may be bent to a side surface of the tantalum wire  111 , and a side surface of the bending portion  134  may be connected to one end portion or the side surface of the tantalum wire  111 . 
     As described in the foregoing embodiment, a length of the tantalum wire  111  may be decreased by disposing the bending portion  134  on the end of the first bent portion  131  and connecting a tantalum wire to the bending portion  134 . Accordingly, a length of the tantalum body  110  may be increased by the decreased length of the tantalum wire  111  to further secure a volume and capacity of the tantalum body  110 . 
     In addition, in the above exemplary embodiment, when the tantalum wire  111  is bonded to the first bent portion  131  through the bending portion  134 , the first bent portion  131  has a high angle of inclination to the second surface  2  of the molded portion  120  or the first connection portion  132 . Therefore, mechanical stress of the first connection portion  132  may be improved in a third direction in which the first bent portion  131  receives a pressure from the tantalum wire  111 . Accordingly, a configuration of the support portion supporting the first connection portion  132 , required in the tantalum capacitor according to the related art, may not be required, so that a volume of the tantalum body  110  may be increased to the extent to achieve high capacitance of the tantalum body  110 . As described above, the first bent portion  131  may have a high angle of inclination “a” to the second surface  2  of the molded portion  120  or the first connection portion  132 . Therefore, assuming that the tantalum wire  111  has the same length, a length of the tantalum body  110  in the first direction X may be increased as compared with a conventional structure, which may also contribute to high capacitance of the tantalum body  110 . 
     In this case, the welding may be performed using, in detail, an electric spot-welding method, but exemplary embodiments are not limited thereto. 
     The other contents are substantially the same as those described in the tantalum capacitor  100  according to an embodiment, and a detailed description thereof will be omitted. 
       FIG.  7    is a perspective view of a tantalum capacitor according to another embodiment. 
     Referring to  FIG.  7   , a tantalum capacitor  400  according to another embodiment may include an anode lead frame  130  which does not include a lead portion and includes only a first bent portion  131  and a first connection portion  132 , as compared with the tantalum capacitor  100  according to the embodiment. Therefore, a description will be provided for only a structure of the anode lead frame  131 . Descriptions of the other configurations of the present embodiment may be substituted with those of an embodiment as it is. 
     As illustrated in  7 , when the anode lead frame  130  does not have an additional cut surface, the anode lead frame  130  may include a first bent portion  131  and a first connection portion  132  and may not include a lead portion. In this case, the anode lead frame  130  may be exposed outwardly of the molded portion  120  through only the first connection portion  132 . Such a structure is a structure in which the connection portion is exposed to only the second surface  2  of the molded portion  130 , and is advantageous in preventing short-circuits with other components and increasing board mounting density. 
     The other contents are substantially the same as those described in the tantalum capacitor  100  according to an embodiment, and a detailed description thereof will be omitted. 
       FIG.  8    is a side view of a tantalum capacitor according to another embodiment. 
     Referring to  FIG.  7   , a tantalum capacitor  500  according to another embodiment may further include a conductive adhesive layer  150  disposed between a tantalum body  110  and a cathode lead frame  140 . Therefore, a description will be provided for only a structure of the conductive adhesive layer  150 . Descriptions of the other configurations of the present embodiment may be substituted with those of an embodiment as it is. 
     In an exemplary embodiment, a conductive adhesive layer  150  may be disposed between a second connection portion  142  of the cathode lead frame  140  and the tantalum body  110 . In addition, a conductive adhesive layer may be disposed between a second bending portion  141  of the cathode lead frame  140  and the tantalum body  110 . 
     The conductive adhesive layer  150  may be formed by applying a predetermined amount of conductive adhesive including, for example, an epoxy-based thermosetting resin and a conductive metal powder such as silver (Ag) and curing the applied conductive adhesive, but exemplary embodiments are not limited thereto. When the conductive adhesive layer  150  is applied to the tantalum capacitor  110  according to the present disclosure, adhesion strength of the anode lead frame  140  may be improved. 
     As described above, a tantalum capacitor, which may implement high capacitance, may be provided. 
     In addition, a tantalum capacitor, having improved reliability by increasing mechanical strength, may be provided. 
     In addition, a tantalum capacitor, which may improve a breakdown voltage (BDV) by increasing a withstand voltage, may be provided. 
     In addition, a tantalum capacitor, which may prevent short-circuits caused by a contact between a terminal and a tantalum body, may be provided. 
     In addition, a tantalum capacitor, which may reduce equivalent series resistance (ESR), may be provided. 
     While exemplary embodiments have been shown and described above, it will be apparent to those skilled in the art that modifications and variations could be made without departing from the scope of the present disclosure as defined by the appended claims.