JP2002367862A - Solid electrolytic capacitor and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid electrolytic capacitor capable of being manufactured small and excellent in connection between an anode wire and anode lead. SOLUTION: The solid electrolytic capacitor 1 is formed with a capacitor element C sealed inside a resin package 6 and extending an anode wire 7 from an element body 4. The capacitor 1 comprises an anode lead 3 connected to the anode wire 7, and a cathode lead 2 connected to the element body 4. The anode lead 3 and the cathode lead 2 are formed by a plate conductor and their respective bottom faces are exposed to the down face of the resin package 6 as terminals, and the element body 4 is connected to a top face 2a of the cathode lead 2 and the anode wire 7 is connected to a top face 3a of the anode lead 3 through a conductive beam member 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid electrolytic capacitor that can be surface-mounted on, for example, a printed circuit board, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, capacitors have been widely used in electronic circuits. Among capacitors, electrolytic capacitors are often used in power circuits and the like because of their relatively small size and large capacity. Typical electrolytic capacitors include aluminum electrolytic capacitors, tantalum electrolytic capacitors, and the like.A tantalum electrolytic capacitor, which is excellent in terms of leakage current characteristics, frequency characteristics, and temperature characteristics, requires those characteristics. It is often used for noise limiter circuits, filter circuits, and the like.

FIGS. 34 and 35 show an example of a conventional tantalum solid electrolytic capacitor (hereinafter simply referred to as "solid electrolytic capacitor"). The solid electrolytic capacitor 61 includes a cathode lead 62 and an anode lead 63, a capacitor element C1, and a resin package 65 that partially seals them. The capacitor element C1 has an element body 64 and an anode wire 66 extending from one end surface 64a thereof. A metal layer 67 is formed on the element body 64 so as to cover the outer surface thereof. The metal layer 67 is electrically connected to the cathode lead 62. The anode wire 66 is electrically connected to the anode lead 63.

In the method of manufacturing the solid electrolytic capacitor 61, first, an element body 64 is attached to a cathode lead 62 formed on a manufacturing lead frame (not shown) by a conductive adhesive 6.
The anode wire 66 extending from the element body 64 is connected to the anode lead 63 similarly formed on the manufacturing lead frame by spot welding or the like. afterwards,
These are sealed with an epoxy resin or the like to form a resin package 65. Each of the leads 62 and 63 extending from the resin package 65 to the outside is cut from the manufacturing lead frame and bent into a predetermined shape.

[0005]

When the leads 62 and 63 are bent into a predetermined shape, a considerable bending stress is applied to the resin package 65. Therefore, the solid electrolytic capacitor 61 is required to have strength enough to withstand such bending stress, and usually, the resin package 65 is relatively thick to avoid damage due to bending stress. However, if the thickness of the resin package 65 is increased, a portion other than the volume of the element body 64 is increased, which leads to an increase in the size of the product.

In the solid electrolytic capacitor 61,
In recent years, the need for higher capacity has been increasing. Generally, in order to obtain a high capacity in a solid electrolytic capacitor, it is necessary to increase the size of the capacitor element itself. Therefore, it is necessary to increase the size of the solid electrolytic capacitor that houses the capacitor.

However, the mounting density of a printed wiring board on which the solid electrolytic capacitor 61 is mounted is becoming higher and higher with the miniaturization of electronic components. In the solid electrolytic capacitor 61 as well, a demand for downsizing is unavoidable, and at present it is a matter that is contrary to the increase in size for obtaining a high-capacity solid electrolytic capacitor.

In the capacitor element C1, the anode wire 66 extending from the element body 64 is usually made of tantalum. Therefore, the anode wire 66 has a problem that it is difficult to connect to the anode lead 63 made of, for example, copper due to the compatibility of the material.

The present invention has been conceived in view of the above-mentioned circumstances, and provides a solid electrolytic capacitor which can be reduced in size and has a good bonding property between an anode wire and an anode lead. The task is to provide.

[0010]

DISCLOSURE OF THE INVENTION In order to solve the above problems, the present invention employs the following technical means.

The solid electrolytic capacitor provided by the first aspect of the present invention is a solid electrolytic capacitor in which a capacitor element having an anode wire extending from an element body is sealed in a resin package. An anode lead that conducts to a wire and a cathode lead that conducts to the element body are provided. The anode lead and the cathode lead are formed of a plate-like conductor, and their lower surfaces are exposed to the lower surface of the resin package. The element body is connected to the upper surface of the cathode lead, and the anode wire is connected to the upper surface of the anode lead via a conductive girder member. It is characterized by.

According to this configuration, in the resin package, the element body is connected to the upper surface of the cathode lead, and the anode wire extending from the element body is connected to the upper surface of the anode lead via the conductive girder member. The lower surfaces of the anode lead and the cathode lead are exposed to the lower surface of the resin package. That is, in the solid electrolytic capacitor of the present invention, the cathode lead supports the element main body while being electrically connected thereto, and is exposed on the lower surface as a terminal. on the other hand,
The anode lead supports the anode wire therethrough while conducting with the conductive girder member, and is exposed on the lower surface as a terminal. Therefore, the solid electrolytic capacitor can be surface-mounted on, for example, a printed wiring board by the anode lead and the cathode lead.

In the configuration of the present invention, the cathode lead and the anode lead are respectively exposed from the lower surface of the resin package, so that it is not necessary to bend the lead as in the conventional configuration. That is, the bending stress generated at the time of bending is not applied to the resin package, and therefore, the thickness of the resin package does not need to be increased. Therefore, the capacitor element can be provided so as to occupy as much as possible in the resin package. Therefore, when a capacitor element having the same capacity is mounted, in the present invention, the size of the resin package is reduced compared to the conventional configuration. And a further reduction in size can be achieved. In other words, if the size of the resin package is the same, the present invention can mount a capacitor element having a larger capacity than the conventional configuration.

According to a preferred embodiment of the present invention,
A part of the lower surface side of the cathode lead is half-etched or stamped, so that the area of the upper surface to which the element body is connected is sufficiently large compared to the terminal surface exposed on the lower surface of the resin package. I have. According to this configuration, a part of the lower surface of the cathode lead is exposed from the lower surface of the resin package, so that the cathode lead can be surface-mounted on a printed wiring board or the like, while sufficient for connecting the element body on the upper surface. The area can be secured.

According to another preferred embodiment of the present invention, a step is formed at the end of the upper surface of the anode lead by etching or stamping, so that a wider gap is formed between the element body and the anode lead. . According to this configuration, a short circuit between the element body and the anode lead can be prevented, and a larger element body can be mounted. Further, a high-capacity solid electrolytic capacitor can be provided.

According to another preferred embodiment of the present invention, the anode wire is formed of tantalum, and the conductive beam member is formed of nickel or an alloy containing nickel. They are connected by resistance welding. Normally, in a tantalum solid electrolytic capacitor, the anode wire extending from the element body is
Since the conductive girder member is made of tantalum, if the conductive girder member is formed of nickel or an alloy containing nickel, the anode wire and the conductive girder member are satisfactorily joined by electric resistance welding, and the joint strength between the two can be increased. . Therefore, a highly reliable solid electrolytic capacitor can be provided.

According to another preferred embodiment of the present invention, the element body is connected to the upper surface of the cathode lead by a conductive adhesive, and the conductive girder member is electrically connected to the upper surface of the anode lead. Are connected by a conductive adhesive. As described above, since the element body and the conductive girder member are connected to the cathode lead and the anode lead by the conductive adhesive, the manufacture of the solid electrolytic capacitor is facilitated.

A method for manufacturing a solid electrolytic capacitor provided by the second aspect of the present invention is a method for manufacturing a solid electrolytic capacitor in which a capacitor element having an anode wire extending from an element body is sealed in a resin package. A plate-shaped manufacturing device in which unit areas are arranged in a plurality of rows and columns, and in each unit area, a pair of an anode lead and a cathode lead whose inward ends are located at a predetermined gap are respectively arranged. (A) connecting the element body of the capacitor element to the upper surface of each cathode lead and connecting the anode wire extending from the element body to the upper surface of each anode lead via a conductive spar member; And (b) exposing the lower surface of each anode lead and each cathode lead, and enclosing each capacitor element, thereby forming the manufacturing frame. Obtaining a resin sealed intermediate product is characterized by performing the steps comprising: a step of dividing (c) the intermediate product, for each of the unit areas.

In the step (a), a conductive girder member is connected to an anode wire in advance by electric resistance welding, the element body is placed on the upper surface of the cathode lead, and the conductive girder member is placed on the upper surface of the anode lead. The connection can be performed by using a conductive adhesive.

As described above, according to the above-described manufacturing method, the solid electrolytic capacitor according to the first aspect of the present invention can be manufactured at once and in a large amount by using the manufacturing frame. Reduction can be achieved.

The solid electrolytic capacitor provided by the third aspect of the present invention is a solid electrolytic capacitor in which a capacitor element having an anode wire extending from the element body is sealed in a resin package, A cathode pad and an anode pad are formed, and a substrate is provided on a lower surface of which a terminal surface that is electrically connected to the cathode pad and the anode pad is formed, and the element body is connected to the cathode pad of the substrate. In addition, the anode wire is connected to the anode pad of the substrate via a conductive girder member. Specifically, the anode wire is formed of tantalum, and the conductive girder member is formed of nickel or an alloy containing nickel, and both are connected by electric resistance welding. The element body is connected to a cathode pad of the substrate by a conductive adhesive, and the conductive girder member is connected to an anode pad of the substrate by a conductive adhesive.

As described above, even when a substrate on which a cathode pad and an anode pad are formed in place of the above-mentioned leads is used, a structure having the function and effect of the solid electrolytic capacitor provided by the first aspect of the present invention is realized. It is possible to

A method of manufacturing a solid electrolytic capacitor provided by a fourth aspect of the present invention is a method of manufacturing a solid electrolytic capacitor in which a capacitor element having an anode wire extending from an element body is sealed in a resin package. The unit areas are arranged in a plurality of rows and a plurality of columns, and a pair of an anode pad and a cathode pad are arranged on the upper surface of each unit area, each having an inward end separated by a predetermined gap. On the back surface of the unit area, a material substrate having a terminal surface electrically connected to the anode pad and the cathode pad, respectively, is used. Connecting an anode wire extending from the element main body through a girder member, and (b) exposing each terminal surface, And obtaining an intermediate product which the material substrate sealed with resin so as to enclosed the capacitor element,
(C) dividing the intermediate product for each unit area.

In the step (a), the conductive girder member is connected to the anode pad in advance by electric resistance welding, and then the element body is connected to the cathode pad, the conductive girder member is connected to the anode pad, and the conductive adhesive material It can be done by connecting.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be specifically described below with reference to the accompanying drawings.

FIGS. 1 to 4 are views showing a tantalum solid electrolytic capacitor (hereinafter simply referred to as "solid electrolytic capacitor") according to a first embodiment of the present invention. The solid electrolytic capacitor 1 includes a cathode lead 2 and an anode lead 3 arranged at a predetermined gap, a capacitor element C connected to the cathode lead 2, and a conductive girder member 5 connected to the anode lead 3. And a resin package 6 formed by sealing them with a thermosetting resin such as an epoxy resin.

The capacitor element C has a substantially rectangular parallelepiped element body 4, and an anode wire 7 extends from one end face 4a. As shown in FIG. 5, the element body 4 has a base end portion of the anode wire 7 embedded in a porous sintered body 4A obtained by compression molding and sintering a metal powder such as tantalum. An oxide film 4B as a dielectric is formed on the surface,
Further, a semiconductor layer 4C and a graphite layer 4D are formed on the outer peripheral surface of the porous sintered body 4A, respectively.
The surface of D is configured to be covered with a metal layer 8 made of silver or the like. That is, the metal layer 8 functions as a cathode and is formed on the side surface 4b and the other end surface 4c of the element body 4 (see FIGS. 2 and 3). The element body 4 is connected to the upper surface 2a of the cathode lead 2 by, for example, a conductive adhesive. The porous sintered body 4A may be formed of aluminum, niobium, or the like.

The cathode lead 2 is formed of a plate-like conductor made of, for example, copper, and a part of the lower surface is half-etched. As a result of this process, the cathode lead 2 has a thick portion 11 having a predetermined thickness in the thickness direction, and a thin portion 12 formed thinner in the thickness direction. That is, the lower surface 2c of the cathode lead 2 (see FIGS. 3 and 4) is exposed as a terminal surface on the lower surface of the resin package 6, and for example, a conductor pattern formed on the surface of a printed wiring board (not shown) By soldering, the solid electrolytic capacitor 1 can be surface-mounted on a printed wiring board. On the other hand, the upper surface 2a of the cathode lead 2 is formed so as to have a sufficiently large area as compared with the lower surface 2c so that the capacitor element C can be mounted, while being formed flat. The end face 2b of the cathode lead 2 is also exposed to the outside.

The anode wire 7 of the capacitor element C is formed of tantalum or the like, which is the same kind of metal as the porous sintered body, and extends from one end surface 4a of the element body 4 to a predetermined length via a resin ring 9. ing. The anode wire 7 is connected to the upper surface 3 a of the anode lead 3 via the conductive girder member 5.

The anode lead 3 is formed of a plate-like conductor made of, for example, copper.
A part of the lower surface is half-etched. As a result of this processing, the anode lead 3 has an uneven surface on the lower surface, and has a thick portion 13 having a predetermined thickness in the thickness direction and a thin portion 14 formed thinner in the thickness direction. The anode lead 3 is arranged such that its upper surface 3a is flat and substantially flush with the upper surface 2a of the cathode lead 2. The upper surface 3a of the anode lead 3 is smaller than the upper surface 2a of the cathode lead 2 and is formed to have an area on which the conductive beam member 5 can be mounted. The lower surface 3c of the anode lead 3 is exposed as a terminal surface on the lower surface of the resin package 6, so that the solid electrolytic capacitor 1 can be surface-mounted on a printed wiring board or the like. The end face 3b of the anode lead 3 is also exposed to the outside.

The conductive girder member 5 is made of a substantially rectangular parallelepiped, for example, nickel or an alloy containing nickel typified by 42 alloy. The conductive girder member 5 is connected to the upper surface 3a of the anode lead 3 by a conductive adhesive. The conductive girder member 5 is provided to electrically conduct the anode wire 7 and the anode lead 3 extending in a substantially horizontal direction when the element body 4 is connected to the cathode lead 2.
That is, since the anode wire 7 extends from substantially the center of the one end surface 4a of the element body 4, when the capacitor element C is connected to the cathode lead 2, a gap is generated between the anode wire 7 and the anode lead 3. It becomes non-conductive. Therefore, the upper surface 3a of the anode lead 3 is substantially raised by the conductive girder member 5, and the anode wire 7 and the anode lead 3 are electrically connected. Therefore, the height of the conductive girder member 5 is set to be substantially equal to the interval H (see FIG. 3) between the lower surface of the anode wire 7 extending substantially in the horizontal direction and the upper surface 3a of the anode lead 3. I have.

The material of the conductive girder member 5 is determined in consideration of the fact that the bonding property with the anode wire 7 made of tantalum is improved.
a and the anode wire 7 are connected by, for example, electric resistance welding of spot welding. Here, the conductive girder member 5
It is also conceivable that the anode wire 7 is connected to the anode wire 7 by, for example, conductive resin paste or soldering. However, since the anode wire 7 has a substantially cylindrical shape, the conductive girder member 5
Has a small contact area with the upper surface 5a, and in the case of the conductive resin paste, the connection resistance increases and the impedance characteristics deteriorate. Therefore, the material of the above-mentioned conductive girder member 5 is selected so that a stronger bonding strength is obtained between the conductive girder member 5 and the anode wire 7, and electric resistance welding is adopted as a method of connecting both members. .

The resin package 6 includes a capacitor element C,
The solid electrolytic capacitor 1 is provided so as to cover the conductive girder member 5, the cathode lead 2, the anode lead 3, and the like, and form the appearance of the solid electrolytic capacitor 1. In this case, on the lower surface side of the resin package 6, the lower surfaces 2c and 3c of the cathode lead 2 and the anode lead 3 are exposed to the outside, respectively, and the exposed lower surfaces 2c and 3c have substantially the same size as each other (FIG. 4).
reference).

As described above, according to the solid electrolytic capacitor 1 of the first embodiment, the cathode lead 2 supports the element body 4 and is exposed on the lower surface as a terminal. On the other hand, the anode lead 3 supports the anode wire 7 through the conductive girder member 5 while being electrically connected thereto, and is exposed on the lower surface as a terminal. Therefore, the cathode lead 2 and the anode lead 3 exposed from the lower surface of the resin package 6
This solid electrolytic capacitor 1 can be surface-mounted on a printed wiring board, for example.

In the configuration of the first embodiment, the cathode lead 2 and the anode lead 3 are respectively connected to the resin package 6.
As a result, the lead does not need to be bent unlike the conventional configuration. That is, the bending stress generated at the time of bending is not applied to the resin package 6, and therefore, the thickness of the resin package 6 does not need to be increased. Therefore, since the capacitor element C can be provided so as to occupy as much as possible in the resin package 6, when the capacitor element C having the same capacity is mounted, the size of the resin package 6 is smaller in the present invention than in the conventional configuration. It can be formed small, and further downsizing can be achieved. In other words, the resin package 6
Are the same, the present invention can mount a capacitor element C having a larger capacity than the conventional configuration.

The conductive girder member 5 may have various shapes as described below. For example, as shown in FIG. 6, a conductive girder member 5A as a modification of the conductive girder member 5 may have a shape in which a groove 15 is formed on the upper surface 5a. The groove 15 has an inner diameter that is substantially the same as or slightly larger than the outer diameter of the anode wire 7. By mounting the anode wire 7 in the groove 15, the contact area between the anode wire 7 and the conductive beam member 5 </ b> A is reduced. By performing electric resistance welding, the two can be more firmly connected.

Further, as shown in FIG.
The conductive spar member 5 </ b> B as another modification may have a shape in which a through hole 16 penetrating in the thickness direction is formed.
The inner diameter of the through-hole 16 is slightly larger than the outer diameter of the anode wire 7. The anode wire 7 is inserted into the through-hole 16 and electric resistance welding is performed, so that the anode wire 7 and the conductive girder member 5 </ b> B are formed. And can be connected more firmly.

Next, a method for manufacturing the solid electrolytic capacitor will be described with reference to FIGS. 5, 8 to 16. First, as shown in FIG. 5, the element main body 4 of the capacitor element C is formed by compressing and sintering a metal powder such as tantalum to form a porous sintered body 4A. The base end of the wire 7 is buried, then an oxide film 4B functioning as a dielectric is formed on the powder surface of the porous sintered body 4A, and further, a semiconductor layer 4C, a graphite layer 4D,
And the metal layer 8 is laminated.

The capacitor element C is, as shown in FIG.
The tip of the anode wire 7 extending from the element main body 4 is welded and connected to the band-shaped tie bar 21, and a plurality of capacitor elements C are connected to the tie bar 21 at predetermined intervals in the next step. move on.

In the next step, as shown in FIG. 9, a rod-shaped conductive girder member 5 having a predetermined length is prepared, and it is positioned so as to span the anode wires 7 of a plurality of capacitor elements C. Next, the bar-shaped conductive beam member 5 and the anode wire 7 are connected by electric resistance welding such as spot welding. In this case, the anode wire 7 is made of tantalum, and the conductive beam member 5 is made of 42 alloy or the like that is compatible with tantalum.

Thereafter, the anode wire 7 is cut along the cutting line L1 shown in FIG. As a result, as shown in FIG. 10, a capacitor element C in which an excess portion of the anode wire 7 has been cut is obtained. Next, the bar-shaped conductive girder member 5 is cut along a cutting line L2 shown in FIG.
Remove excess parts. As a result, a conductive girder member 5 having a length corresponding to each capacitor element C is obtained, and each of the conductive girder members 5 is connected to the capacitor element C connected to the anode wire 7.
Get.

On the other hand, as shown in FIG. 11, the cathode lead 2 and the anode lead 3 have a thickness of, for example, 0.15 mm.
A plate-like frame 23 of about mm is used. The plate-shaped frame 23 has, at a side edge thereof, an engagement hole 24 for fixing to a fixing table or the like (not shown).

FIG. 12 is an enlarged view of a region A indicated by a dotted line in FIG. The plate-shaped frame 23 has been subjected to a punching process, and unit regions B (see FIG. 12) that will eventually become solid electrolytic capacitors are arranged in a plurality of rows and a plurality of columns. In each unit area B, a pair of the anode lead 3 and the cathode lead 2 is arranged such that their inward ends are located with a predetermined clearance therebetween. The leads 2 and 3 in each unit area B are connected by an outer frame of the plate-like frame 23 and a continuous portion 28. Further, as shown in FIG. 13, the back side of each of the leads 2 and 3 in the plate-shaped frame 23 is subjected to a half-etching process, and the thin portions 12 and 14 shown in FIG. 3 are respectively formed. That is, the hatched portion D in FIG. 13 is a portion where the half etching process is performed,
These are the thin portions 12 and 14.

A capacitor element C to which the conductive girder member 5 is connected is connected to each of the leads 2 and 3 of the plate frame 23. Specifically, as shown in FIG. 14, a conductive paste made of, for example, an Ag paste is applied as a conductive adhesive 30 to a predetermined portion on the upper surfaces 2 a and 3 a of the leads 2 and 3. The element main body 4 is positioned and mounted on the upper surface 2 a of the cathode lead 2, and at the same time, the conductive beam member 5 is positioned and mounted on the upper surface 3 a of the anode lead 3.
Thereby, the capacitor element C and the conductive girder member 5
Are mounted on the leads 2 and 3 and are electrically connected.

Thereafter, the resin package 6 is formed by, for example, transfer molding. Specifically, as shown in FIG. 15, the surroundings of the plurality of capacitor elements C and the plate-shaped frame 23 are surrounded from above and below using predetermined molds 31 and 32. Next, a thermosetting resin such as an epoxy resin in a flowing state is injected into the cavity 33 and solidified, whereby the plate frame 23, the capacitor element C, and the conductive girder member 5 are integrally molded to obtain an intermediate product. .

Next, FIG. 16 (region A of the plate-like frame 23)
Of the leads 2 and 3 as terminals which are finally exposed to the outside as shown in FIG. Thereafter, the molded intermediate product is cut in the vertical direction by cutting a region indicated by the hatched portion E in FIG. 16 with a dicing saw having a width of about 0.3 mm, for example, to obtain a horizontally long secondary intermediate product.
Next, by cutting off the area indicated by the hatched portion F in FIG. 16, the horizontally long secondary intermediate product is cut in the vertical direction, and the solid electrolytic capacitor 1 shown in FIGS. 1 and 2 is obtained.

As described above, in the above-described manufacturing method, the solid electrolytic capacitor 1 can be manufactured in large quantities at one time by using the plate-shaped frame 23, so that the manufacturing cost can be reduced. In the above-described manufacturing method, the conductive girder member 5 was connected to the anode lead 3 after being joined to the anode wire 7, but instead of this,
The conductive girder member 5 may be connected to the anode lead 3 in advance and then joined to the anode wire 7.

FIG. 17 is a partially cutaway perspective view showing a first modification of the solid electrolytic capacitor shown in FIG. In this solid electrolytic capacitor 1A, the upper end of the anode lead 3
A step 17 is formed. Step 17 is the anode lead 3
Is formed, for example, by etching.
Other configurations are substantially the same as those of the first embodiment shown in FIG.

For example, when the element body 4 is formed large or when the resin package 6 is compressed and deformed when the resin package 6 is molded, one end face 4 of the element body 4 is formed.
The lower edge of “a” may come in contact with the anode lead 3. However, by providing the step 17 on the anode lead 3, a wider gap is created between the one end face 4a of the element body 4 and the anode lead 3 (see FIG. 18). Thus, the possibility that the element body 4 comes into contact with the anode lead 3 is reduced, and a short circuit between the two can be prevented. Therefore, a larger element body 4 can be mounted. Further, a high-capacity solid electrolytic capacitor can be provided.

FIG. 19 is a partially cutaway perspective view showing a second modification of the solid electrolytic capacitor shown in FIG. In this solid electrolytic capacitor 1 </ b> B, unlike the conductive girder member 5 shown in FIG. 1, the conductive girder member 35 extends in the longitudinal direction and both end surfaces 35 a reach the side surfaces of the resin package 6. That is, both end surfaces 35a of the conductive girder member 35 are exposed to the outside. Other configurations are substantially the same as those of the embodiment shown in FIG.

According to the above configuration, both end surfaces 35a of the conductive girder member 35 are exposed in the vicinity of the anode lead 3, which is a terminal on the anode side, in the resin package 6. Therefore, the solid electrolytic capacitor 1B has an advantage that the distinction between the anode side and the cathode side of the solid electrolytic capacitor 1B can be immediately grasped from the outside, and the handling of the solid electrolytic capacitor 1B becomes easy.

In manufacturing the solid electrolytic capacitor element 1B, the following method may be used. That is,
The conductive girder member 3 is previously attached to the anode wire 7 of the capacitor element C.
5, a bar-shaped conductive girder member 3 having a predetermined length
Prepare 5 Then, it is connected to each anode lead 3 of the plate-like frame 23 by bridging it, and the anode wire 7 of each capacitor element C is positioned and connected to the rod-shaped conductive girder member 35. After that, the molded plate-like frame 23 is cut together with the conductive girder member 35. In this way, since the bar-shaped conductive girder member 35 is cut directly, both end surfaces 35a can be easily exposed to the outside, and the production can be performed efficiently.

FIG. 20 is a partially cutaway perspective view showing a third modification of the solid electrolytic capacitor shown in FIG. In the solid electrolytic capacitor 1C, the cathode lead 2 and the anode lead 3 are configured not to be exposed from both end surfaces of the resin package 6. That is, in the solid electrolytic capacitor 1 shown in FIG. 1, the side surfaces 2b and 3b of each of the leads 2 and 3 are
Although each of the leads 2 and 3 is provided on the inner portion of the resin package 6 and the side surfaces 2 b and 3 b are provided on the inner surface of the resin package 6. Not exposed to the outside. That is,
The lower surfaces 2c and 3c of the leads 2 and 3 are exposed only from the lower surface of the resin package 6. For other configurations,
This is substantially the same as the embodiment shown in FIG.

According to such a configuration, each of the leads 2 and 3
Is provided inside the resin package 6, so that, for example, when the solid electrolytic capacitor 1C is mounted on a printed wiring board (not shown), other electronic components mounted near the solid electrolytic capacitor 1C In addition, it is possible to prevent problems such as a short circuit between the leads 2 and 3 as terminals.

FIG. 21 is a partially cutaway perspective view showing a fourth modification of the solid electrolytic capacitor shown in FIG. According to the figure, in this solid electrolytic capacitor 1D, the conductive girder member 35 extends in the longitudinal direction, its both end surfaces 35a are exposed to the outside, and the cathode lead 2 and the anode lead 3 are located inside the resin package 6. The resin package 6
The lower surfaces 2c and 3c of the leads 2 and 3 are exposed only from the lower surface of the lead. As shown in FIG. 21, the anode lead 3 connected to the conductive girder member 35 is wide along the longitudinal direction of the conductive girder member 35 in order to stably mount the conductive girder member 35. May be formed. Other configurations are substantially the same as those of the embodiment shown in FIG. With such a configuration, the anode lead 3 can stably mount the conductive girder member 35.

FIG. 22 is a partially cutaway perspective view showing a solid electrolytic capacitor according to a second embodiment of the present invention. In this embodiment, the solid electrolytic capacitor 1E includes an insulating substrate 40 instead of the cathode lead 2 and the anode lead 3, as shown in FIG. 5 are connected.

The substrate 40 is made of glass epoxy resin, polyimide resin such as BT resin, ceramics, or the like, and has a cathode pad 41 and an anode pad 42 formed on the upper surface 40a. Further, on the lower surface 40c, there are formed terminal surfaces 41A and 42A which are electrically connected to the cathode pad 41 and the anode pad 42, respectively. That is, the cathode pad 41 is electrically connected to the terminal surface 41A of the lower surface 40c via the conductor portion 41B formed on the one end surface 40b of the substrate 40. On the other hand, the anode pad 42 is electrically connected to the terminal surface 42A of the lower surface 40c via the conductor portion 42B formed on the other end surface 40d of the substrate 40.

The element body 4 of the capacitor element C is connected to the upper surface of the cathode pad 41 via a conductive adhesive. Further, on the upper surface of the anode pad 42, the conductive girder member 5 is provided.
Are connected via a conductive adhesive.

The resin package 6 is provided on the upper surface 40 of the substrate 40.
a is formed so as to cover the capacitor element C, the conductive girder member 5 and a part of the cathode and anode pads 41 and 42, and is not formed at both ends of the substrate 40. Other configurations are substantially the same as those in the first embodiment.

According to this configuration, as the members for connecting and supporting the capacitor element C and the conductive beam member 5, the cathode pads 41 and the anode pads 42 are formed instead of the leads 2 and 3 shown in the first embodiment. A substrate 40 is used. Therefore, even in this configuration, unlike the conventional configuration, an operation such as bending of the lead does not occur, and no bending stress is applied to the resin package 6. Therefore, as in the first embodiment, the capacitor element C can be provided so as to occupy as much as possible in the resin package 6, so that when the capacitor element C having the same capacity is mounted, the size of the resin package 6 can be reduced. , Miniaturization becomes possible.

Next, a method of manufacturing the solid electrolytic capacitor shown in FIG. 22 will be described with reference to FIGS.
In this manufacturing method, the flat material substrate 44 shown in FIG.
Is used. In the material substrate 44, a plurality of slits 45 extending in the horizontal direction are formed in parallel at a predetermined interval in the vertical direction, and finally a solid electrolytic capacitor is formed in the strip-shaped member 46 between the slits 45. A plurality of unit areas G (see FIG. 24) are arranged. In the belt-shaped member 46,
As shown in FIG. 24, a cathode pad 41 and an anode pad 42 are formed on each unit region G on the surface by a known photolithography method or the like. In addition, the band-shaped member 4
In FIG. 6, as shown in FIG. 25, terminal surfaces 41A and 42A as conductor patterns are formed for each unit region G on the back surface by a known photolithography method or the like. The terminal surfaces 41A and 42A are provided at both end surfaces 46a of each band-shaped member 46.
Conductor portion 41 formed by, for example, electrolytic plating or the like.
B and 42B (see FIG. 22) are electrically connected to the cathode pad 41 and the anode pad 42, respectively.

Next, as shown in FIG. 26, capacitor element C is connected to cathode pad 41 and anode pad 42. Specifically, in the first embodiment, FIGS.
As described above, the capacitor element C to which the conductive girder member 5 is connected is separately manufactured. Then, each cathode pad 4
The conductive adhesive 30 is applied to the upper surface 41 a of the first electrode 41 and the upper surface 42 a of each anode pad 42. Then, each element body 4 is positioned and mounted on each cathode pad 41 to which the conductive adhesive 30 has been applied. At this time, the anode wire 7 extending from the element body 4 is positioned and mounted on the upper surface 5a of the conductive girder member 5, and the anode wire 7 is connected to the conductive girder member 5 by electric resistance welding.

Thereafter, a resin package 6 is formed.
More specifically, as shown in FIG. 27, a plurality of capacitor elements C, conductive girder members 5 and band members 46 are surrounded from above and below by using predetermined molds 47 and 48, By injecting and solidifying a resin or the like, the belt-shaped member 46, each capacitor element C, and the conductive beam member 5 are integrally molded to obtain an intermediate product. In this case, the terminal surfaces 41A and 42A on the back surface of the band-shaped member 46 have
Since the resin package 6 is not formed, it is exposed to the outside.

Next, the molded intermediate product is divided into single solid electrolytic capacitors. Specifically, the intermediate product is cut in the vertical direction by cutting off the area indicated by the shaded portion J in FIG. 28, and the single solid electrolytic capacitor 1E shown in FIG. 22 is obtained. As described above, also in the above manufacturing method, the solid electrolytic capacitor 1E
Can be manufactured at once and in large quantities, so that the manufacturing cost can be reduced.

FIG. 29 is a partially cutaway perspective view showing a first modification of the solid electrolytic capacitor shown in FIG. In this solid electrolytic capacitor 1F, the conductive girder member 51 extends in the longitudinal direction, and both end surfaces 55a are exposed to the outside. Other configurations are substantially the same as those of the second embodiment shown in FIG. With this configuration, the same operation and effect as those of the second modification of the first embodiment shown in FIG. 19 can be obtained.

The method of manufacturing the solid electrolytic capacitor 1F is the same as that of the solid electrolytic capacitor 1F shown in FIGS.
The method is substantially the same as the method of manufacturing E, but the following method may be used. That is, the conductive girder member 55 connected to the capacitor element C is a rod-shaped member extending to a predetermined length. Then, as shown in FIG. 30, when the conductive girder member 55 is connected to the anode pad 42, the rod-shaped conductive girder member 5
5 is connected to each anode pad 42 via the conductive adhesive 30 so as to be bridged. In addition, each cathode pad 4
1, each element body 4 is connected via a conductive adhesive 30.

Thereafter, a resin package 6 is formed so as to cover each capacitor element C. Then, the intermediate product is cut together with the conductive girder member 55 by cutting off the area indicated by the hatched portion K in FIG. As a result, both ends 55 a of the conductive girder member 55 are provided on the cut surface of each resin package 6.
Will be exposed to the outside.

In addition to this manufacturing method, the bar-shaped conductive girder member 55 is not connected to the capacitor element C in advance, but is directly connected to the anode pad 42 of the band-shaped member 46 via the conductive adhesive 30. After that, the anode wire 7 of the capacitor element C may be connected to the upper surface 55a of the bar-shaped conductive girder member 55 by electric resistance welding.

As described above, by using the rod-shaped conductive girder members 55, it is not necessary to manufacture a plurality of conductive girder members 55 for each capacitor element C. Since the labor of the operation can be omitted, the efficiency of production can be improved.

FIG. 32 is a partially cutaway perspective view showing a second modification of the solid electrolytic capacitor shown in FIG. According to the solid electrolytic capacitor 1G, a groove 57 extending in the thickness direction of the substrate 56 is formed in the substrate 56 at an intermediate portion between both end surfaces 56b and 56d. Zu). Here, the groove 57 on the near side of the substrate 56
In the following, the anode pad 42 is formed in the groove 57
Terminal surface 42 formed on lower surface 56c of substrate 56
A is electrically connected to A. That is, the groove 57
A conductive layer 58 made of copper is formed on the inner surface of the substrate 56 by, for example, electroless plating, and the conductive layer 58 is electrically connected to the anode pad 42 on the upper surface 56 a side of the substrate 56.
It is electrically connected to the terminal surface 42A on the lower surface 56c side of the substrate 56. The cathode pad 41 is connected to one end face 56b (not shown).
The terminal surface 41A of the lower surface 56c of the substrate 56 is formed by the side groove.
And are electrically connected to each other.

The resin package 6 is formed over the entire upper surface 56a of the substrate 56. Other configurations are substantially the same as those of the seventh embodiment shown in FIG. 29, and have the same functions and effects. The substrate 56 is formed with a through hole (not shown) penetrating in the thickness direction of the substrate 56 instead of the groove portion 57, and the upper surface 5 of the substrate 56 is formed by a conductor layer formed on the inner surface of the through hole.
The anode pad 42 (or the cathode pad 41) on the 6a side may be electrically connected to the terminal surface 42A (or the terminal surface 41A) on the lower surface 56c.

The groove 57 may be formed at the same time as when the slit 45 is formed by punching the material substrate 44 shown in FIG. Alternatively, a groove may be formed by forming a through hole in advance with a drill or the like and cutting out half of the through hole by punching.

FIG. 33 is a partially cutaway perspective view showing a third modification of the solid electrolytic capacitor shown in FIG. According to the figure, in the solid electrolytic capacitor 1H, the conductive girder member 55 extends in the longitudinal direction, and both end surfaces 55a are exposed to the outside. Also, both end surfaces 56 of the substrate 56
A groove 57 extending in the thickness direction of the substrate 56 is formed at an intermediate portion between the substrate b and 56d (a groove on one end surface 56b side is not shown).
6 is electrically connected to the terminal surface 42A formed on the lower surface 56c. Other configurations are substantially the same as those of the second modification of the second embodiment shown in FIG. With such a configuration, the same operation and effect as those of the second modification of the second embodiment can be obtained.

Of course, the scope of the present invention is not limited to the above embodiment. For example, in the above embodiment, the tantalum solid electrolytic capacitor using tantalum as the metal on the anode side was described, but the above-described configuration may be applied to a solid electrolytic capacitor using aluminum, niobium, or the like as the metal on the anode side. Good. Further, the solid electrolytic capacitor described in the above embodiment may be provided with a fuse wire.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view showing a structure of a solid electrolytic capacitor according to a first embodiment of the present invention.

FIG. 2 is a top perspective view showing the solid electrolytic capacitor of FIG.

FIG. 3 is a side perspective view showing the solid electrolytic capacitor of FIG. 1;

FIG. 4 is a bottom view showing the solid electrolytic capacitor of FIG. 1;

FIG. 5 is a sectional view of a capacitor element.

FIG. 6 is a perspective view showing another conductive girder member.

FIG. 7 is a perspective view showing still another conductive girder member.

FIG. 8 is a diagram illustrating a method of manufacturing the solid electrolytic capacitor of FIG.

FIG. 9 is a diagram illustrating a method of manufacturing the solid electrolytic capacitor of FIG.

FIG. 10 is a diagram illustrating a method of manufacturing the solid electrolytic capacitor of FIG.

FIG. 11 is a diagram illustrating a method of manufacturing the solid electrolytic capacitor of FIG.

FIG. 12 is a diagram illustrating a method of manufacturing the solid electrolytic capacitor of FIG.

FIG. 13 is a diagram illustrating a method of manufacturing the solid electrolytic capacitor of FIG.

FIG. 14 is a diagram illustrating a method of manufacturing the solid electrolytic capacitor of FIG.

FIG. 15 is a diagram illustrating a method of manufacturing the solid electrolytic capacitor of FIG.

FIG. 16 is a diagram illustrating a method of manufacturing the solid electrolytic capacitor of FIG.

FIG. 17 is a partially cutaway perspective view showing a first modification of the solid electrolytic capacitor according to the first embodiment.

18 is a side perspective view showing the solid electrolytic capacitor of FIG.

FIG. 19 is a partially cutaway perspective view showing a second modification of the solid electrolytic capacitor according to the first embodiment.

FIG. 20 is a partially cutaway perspective view showing a third modification of the solid electrolytic capacitor according to the first embodiment.

FIG. 21 is a partially cutaway perspective view showing a fourth modification of the solid electrolytic capacitor according to the first embodiment.

FIG. 22 is a partially cutaway perspective view showing a solid electrolytic capacitor according to a second embodiment of the present invention.

FIG. 23 is a diagram illustrating a method of manufacturing the solid electrolytic capacitor of FIG.

24 is a diagram illustrating a method of manufacturing the solid electrolytic capacitor of FIG.

25 is a diagram illustrating a method of manufacturing the solid electrolytic capacitor of FIG.

26 is a diagram illustrating a method of manufacturing the solid electrolytic capacitor of FIG.

FIG. 27 is a diagram illustrating a method of manufacturing the solid electrolytic capacitor of FIG.

FIG. 28 is a diagram illustrating the method of manufacturing the solid electrolytic capacitor in FIG.

FIG. 29 is a partially cutaway perspective view showing a first modification of the solid electrolytic capacitor according to the second embodiment.

30 is a view illustrating a method of manufacturing the solid electrolytic capacitor of FIG. 29.

FIG. 31 is a diagram illustrating the method of manufacturing the solid electrolytic capacitor in FIG. 29.

FIG. 32 is a partially cutaway perspective view showing a second modification of the solid electrolytic capacitor according to the second embodiment.

FIG. 33 is a partially cutaway perspective view showing a third modification of the solid electrolytic capacitor according to the second embodiment.

FIG. 34 is a partially cutaway perspective view showing a conventional solid electrolytic capacitor.

FIG. 35 is a side perspective view showing the solid electrolytic capacitor of FIG. 34.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Solid electrolytic capacitor 2 Cathode lead 3 Anode lead 4 Capacitor element 5 Conductive girder member 6 Resin package 7 Anode wire 40 Substrate 41 Cathode pad 42 Anode pad C Capacitor element

Claims (13)

[Claims] 1. A solid electrolytic capacitor in which a capacitor element having an anode wire extending from an element body is sealed in a resin package, wherein the anode lead is electrically connected to the anode wire, and is electrically connected to the element body. A cathode lead, wherein the anode lead and the cathode lead are formed of a plate-like conductor, and their respective lower surfaces are exposed to the lower surface of the resin package to serve as terminal surfaces. A solid electrolytic capacitor connected to the upper surface of the cathode lead, and the anode wire is connected to the upper surface of the anode lead via a conductive girder member. 2. A part of the lower surface side of the cathode lead is half-etched or stamped, so that the area of the upper surface to which the element body is connected is sufficient as compared with the terminal surface exposed on the lower surface of the resin package. The solid electrolytic capacitor according to claim 1, wherein: 3. The solid electrolytic capacitor according to claim 1, wherein a step is formed at an end of an upper surface of the anode lead. 4. The step formed on the anode lead is formed by etching or stamping.
3. The solid electrolytic capacitor according to item 1. 5. The anode wire is formed of tantalum, the conductive girder member is formed of nickel or an alloy containing nickel, and both are connected by electric resistance welding. 5. The solid electrolytic capacitor according to any one of items 1 to 4. 6. The element body is connected to a top surface of the cathode lead by a conductive adhesive, and the conductive girder member is connected to a top surface of the anode lead by a conductive adhesive. 6. The solid electrolytic capacitor according to 5. 7. A method for manufacturing a solid electrolytic capacitor in which a capacitor element having an anode wire extending from an element body is sealed in a resin package, wherein the unit regions are arranged in a plurality of rows and a plurality of columns. In each unit area, a plate-shaped manufacturing frame in which a pair of an anode lead and a cathode lead whose inwardly facing ends are separated by a predetermined gap is used, and (a) the capacitor is provided on the upper surface of each of the cathode leads Connecting the element body of the element and connecting an anode wire extending from the element body to the upper surface of each anode lead via the conductive girder member; and (b) the lower surface of each anode lead and each cathode lead. Exposing the capacitor and enclosing each capacitor element to obtain an intermediate product in which the manufacturing frame is resin-sealed, and (c) removing the intermediate product from the unit area. And performing the steps comprising the steps of dividing each method for producing a solid electrolytic capacitor. 8. In the step (a), a conductive girder member is connected to an anode wire in advance by electric resistance welding.
8. The method for manufacturing a solid electrolytic capacitor according to claim 7, wherein the element main body is connected to an upper surface of a cathode lead, and the conductive beam member is connected to an upper surface of an anode lead by a conductive adhesive. 9. A solid electrolytic capacitor in which a capacitor element having an anode wire extending from an element body is sealed in a resin package, wherein a cathode pad and an anode pad are formed on an upper surface, and the solid electrolytic capacitor is formed on a lower surface. A substrate having a terminal surface formed to be electrically connected to the cathode pad and the anode pad, wherein the element body is connected to the cathode pad of the substrate, and the anode wire is electrically conductive to the anode pad of the substrate. A solid electrolytic capacitor which is connected via a girder member. 10. The anode wire is formed of tantalum, the conductive girder member is formed of nickel or an alloy containing nickel, and both are connected by electric resistance welding. 3. The solid electrolytic capacitor according to item 1. 11. The element body is connected to a cathode pad of the substrate by a conductive adhesive, and the conductive girder member is connected to an anode pad of the substrate by a conductive adhesive. 9. The solid electrolytic capacitor according to 9 or 10. 12. A method for manufacturing a solid electrolytic capacitor in which a capacitor element having an anode wire extending from an element body is sealed in a resin package, wherein the unit regions are arranged in a plurality of rows and a plurality of columns. On the upper surface of each unit region, a pair of an anode pad and a cathode pad whose inward ends are located with a predetermined gap therebetween are respectively arranged, and on the back surface of each unit region, a terminal surface electrically connected to the anode pad and the cathode pad respectively (A) Connect the element body of the capacitor element to each of the cathode pads, and connect the anode wires extending from the element body to each of the anode pads via a conductive girder member. And (b) an intermediate product in which each terminal surface is exposed, and the material substrate is resin-sealed so as to enclose each capacitor element. And obtaining, (c)
And a step of dividing the intermediate product for each unit area. 13. In the step (a), the conductive girder member is connected to the anode pad in advance by electric resistance welding, and the element body is connected to the cathode pad and the conductive girder member is connected to the anode pad. 13. The method for manufacturing a solid electrolytic capacitor according to claim 12, wherein the method is performed by connecting the capacitors.