JP2012134436A - Capacitors and electronic devices - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a capacitor 1 for preventing noise without using other members.
SOLUTION: A multilayer body 2 in which a plurality of dielectric layers 5 are stacked, and a first internal electrode 3a and a second internal electrode 3b provided between the dielectric layers 5 so as to face each other through the dielectric layer 5. And has an internal electrode 3 composed of a first internal electrode 3a and a second internal electrode 3b. The first internal electrode 3a is at least partially divided through a slit 9, and is adjacent to the slit 9. Since the bent portion 10 is opposed to each other through the slit 9 in the adjacent first and second internal electrodes 3a and 3b, the bent direction 10 is Voltage is applied in the intersecting direction, electrostriction occurs, and it is possible to reduce the height of the capacitor 1 as a countermeasure against noise without using a separate member.
[Selection] Figure 2

Description

  The present invention relates to a capacitor and an electronic device.

  Generally, a capacitor is provided on both end surfaces of a laminate in which a plurality of dielectric layers are laminated, an internal electrode provided between the dielectric layers of the laminate, and an internal electrode. And an external electrode. In an electronic device having such a capacitor, the capacitor is mounted on the wiring board with external electrodes soldered to predetermined electrode pads on the wiring board.

  However, when the capacitor using the barium titanate ceramic as the dielectric layer is used in a high voltage and high frequency region, vibration is generated due to electrostriction due to the piezoelectric phenomenon of the dielectric layer. Stress due to vibration generated by this electrostriction is transmitted to the wiring board. Accordingly, the wiring board also vibrates. When the vibration frequency of the wiring board reaches the audible frequency band, an audible sound is generated from the wiring board. That is, a phenomenon called “board squeal” or “squeal” may occur.

  In view of this, an electronic device having a configuration in which one end portion is connected to an external electrode of a capacitor and the other end portion is connected to an electrode pad of a wiring board is employed. The capacitor in such an electronic device is mounted on the wiring board in a state of being separated from the wiring board because the external electrodes at both ends are supported by the pair of terminal members.

  Therefore, the stress due to the electrostriction described above is suppressed by the terminal member and is difficult to be transmitted to the wiring board, so that squeal can be suppressed.

JP 2000-235931 A

  Here, in recent electronic parts industry, downsizing of electronic parts such as capacitors has been strictly demanded. However, the above-described conventional capacitor is mounted on the wiring board in a state of being separated from the wiring board. Therefore, even if the capacitor itself can be reduced in size, it is difficult to reduce the height. Therefore, the electronic device using such a capacitor has a problem that it is difficult to reduce the size.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a capacitor and an electronic device for noise reduction that can be reduced in height.

  A capacitor according to the present invention includes a laminate in which a plurality of dielectric layers are laminated, and a first internal electrode and a second internal electrode provided between the dielectric layers so as to face each other with the dielectric layer interposed therebetween. The first internal electrode includes an internal electrode composed of the first internal electrode and the second internal electrode, and the first internal electrode is at least partially divided through a slit, and the second internal It has a curved part bent to the electrode side.

An electronic device according to the present invention includes the above capacitor and a wiring board provided with an electrode pad on a main surface, and the capacitor electrically connects the first extraction electrode and the second extraction electrode to the electrode pad. And being mounted on the main surface of the wiring board.

  According to the capacitor of the present invention, there is provided a laminated body in which a plurality of dielectric layers are laminated, and a first internal electrode and a second internal electrode provided between the dielectric layers so as to face each other through the dielectric layer. The first internal electrode has an internal electrode composed of a first internal electrode and a second internal electrode, and the first internal electrode is at least partially divided through a slit, and is bent toward the second internal electrode at a portion adjacent to the slit. Therefore, the direction of electrostriction between the bent portion and the second internal electrode is a direction that intersects the direction of electrostriction in the stacking direction of the first and second internal electrodes. Therefore, since the electrostriction between the curved portion and the second internal electrode cancels the electrostriction in the opposing region in the stacking direction of the first and second internal electrodes, the stress due to electrostriction in the entire capacitor can be suppressed.

  As a result, for example, it is not necessary to use a separate member such as a conventional terminal member, so that it is possible to reduce the height of the squeal capacitor.

It is a perspective view which shows an example of embodiment of the electronic device of this invention. (A) is sectional drawing in the AA of the capacitor | condenser shown in FIG. 1, (b) is a longitudinal cross-sectional view of the laminated body of the capacitor | condenser shown in FIG. It is a longitudinal cross-sectional view of the electronic device shown in FIG. (A) is a top view of the internal electrode of the conventional capacitor | condenser, (b) is a top view of the internal electrode of the capacitor | condenser of this invention. It is an enlarged view of the longitudinal cross-sectional view of the laminated body of the capacitor | condenser shown in FIG.2 (b). It is a longitudinal cross-sectional view of the raw laminated body of the capacitor | condenser of this invention, Comprising: It is a figure at the time of pressing with a pressing board. (A)-(c) is a top view which shows the other example of embodiment of the internal electrode shown in FIG. (A) And (b) is a top view which shows the further another example of embodiment of the internal electrode shown in FIG. It is a top view which shows the further another example of embodiment of the internal electrode shown in FIG. It is a longitudinal cross-sectional view which shows the other example of embodiment of the electronic device of this invention. It is an enlarged view of the longitudinal cross-section of the laminated body of the capacitor | condenser of the other example of embodiment of this invention. It is explanatory drawing of the crimping | compression-bonding process in the preparation process of the laminated body of the capacitor | condenser of the other example of embodiment of this invention. It is an enlarged view of the longitudinal cross-section of the laminated body of the capacitor | condenser of the other example of embodiment of this invention. It is an enlarged view of the longitudinal cross-section of the laminated body of the capacitor | condenser of the other example of embodiment of this invention. It is an enlarged view of the longitudinal cross-section of the laminated body of the capacitor | condenser of the other example of embodiment of this invention.

  Hereinafter, an example of an embodiment of a capacitor of the present invention will be described in detail with reference to the drawings.

As shown in FIG. 1, the electronic device 7 includes a wiring board 6 and a capacitor 1 mounted on the wiring board 6. The wiring substrate 6 is a substrate on which an electrode pad 14 to which the capacitor 1 is electrically connected is provided on the surface, and an electronic circuit (not shown) is formed on the surface or inside. The wiring board 6 is not particularly limited, and may not be flexible, for example, or may be a flexible sheet. The wiring board 6 may be a flexible printed circuit board (FPC) on which an electronic circuit is printed, for example.

  The dimensions of the electrode pad 14 are about 0.1 to 5 mm in width and about 0.1 to 5 mm in length when the laminate 2 is viewed in plan. The electrode pad 14 is mainly composed of, for example, an alloy mainly composed of silver such as silver (Ag), copper (Cu), silver-platinum (Ag—Pt), or copper such as a copper-zinc (Cu—Zn) alloy. A conductor material made of an alloy or the like can be used. Further, a plating film may be formed on the surface of the electrode pad 14 as necessary.

  A capacitor 1 shown in FIG. 1 includes a multilayer body 2, an internal electrode 3, and an external electrode 4 as a basic configuration.

  The laminate 2 is formed by laminating a plurality of dielectric layers 5. This laminated body 2 is a rectangular parallelepiped dielectric block formed by laminating, for example, 20 to 2000 layers of a plurality of rectangular dielectric layers 5 formed to have a thickness of 1 to 5 μm per layer, for example.

  Moreover, the dimension of the laminated body 2 makes the length of the long side of the laminated body 2 into 0.4-3.2 mm, for example, and makes the length of the short side of the laminated body 2 into 0.2-1.6 mm, for example.

Examples of the material for the dielectric layer 5 include BaTiO ₃ , CaTiO ₃ , SrTiO _{3, and} CaZrO ₃ . As another _example, BaTiO _3, CaTiO 3, and SrTiO ₃ or CaZrO ₃ as a main component, Mn compound, Fe compound, Cr compounds, Co compounds, or may be Ni compound or the like is added .

  As shown in FIGS. 1 to 3, the laminate 2 includes a first main surface 2 a (upper surface) and a second main surface (lower surface) 2 b that face each other, and a first side surface 2 c and a second surface that face each other. The side surface 2d is formed in a substantially rectangular parallelepiped shape having a first end surface 2e and a second end surface 2f facing each other.

  As shown in FIG. 3, the first external electrode 4a and the second external electrode 4b are connected to the first internal electrode 3a and the second internal electrode 3b, respectively. The first external electrode 4 a and the second external electrode 4 b are provided on the surface of the multilayer body 2. In the following description, when the term “external electrode 4” is simply used, it means both the first external electrode 4a and the second external electrode 4b. In the example shown in FIG. 3, the first external electrode 4 a and the second external electrode 4 b are provided at the end of the multilayer body 2. The external electrode 4 has a thickness of 5 to 50 μm.

  As shown in FIG. 1, the external electrode 4 is electrically connected to the electrode pad 14 and plays a role of ensuring electrical continuity with the wiring board 6.

  As shown in FIG. 3, the first external electrode 4a is formed on the second end face 2f. As shown in FIG. 1, the end of the first external electrode 4a reaches the first and second main surfaces 2a and 2b and the first and second side surfaces 2c and 2d. As shown in FIG. 3, the first external electrode 4a is electrically connected to each of the plurality of first internal electrodes 3a drawn to the second end face 2f.

  As shown in FIG. 3, the second external electrode 4b is formed on the first end face 2e. As shown in FIG. 1, the end of the second external electrode 4b reaches the first and second main surfaces 2a and 2b and the first and second side surfaces 2c and 2d. As shown in FIG. 3, the second external electrode 4b is electrically connected to each of the plurality of second internal electrodes 3b drawn to the first end face 2e.

  In addition, in order to suppress the modification | denaturation etc. of the external electrode 4 on the surface of the external electrode 4, it is preferable that 1 or several plating films, such as Ni plating film and Sn plating film, are formed, for example. For example, a laminate of a Ni plating film and a Sn plating film may be formed on the surface of the external electrode 4.

  A method for bonding the external electrode 4 to the wiring substrate 6 is not particularly limited. For example, an appropriate joining member such as high-temperature solder such as Sn-Sb-based high-temperature solder, Sb-Pb eutectic solder, Sn-Ag-Cu-based Pb-free solder, Sn-Cu-based Pb-free solder, or resin containing conductive fine particles The external electrode 4 and the wiring board 6 can be joined using

  The first internal electrode 3a and the second internal electrode 3b are provided between the dielectric layers 5 so as to face each other with the dielectric layer 5 interposed therebetween. In the following description, the expression “internal electrode 3” simply means both the first internal electrode 3a and the second internal electrode 3b.

  In the example illustrated in FIG. 3, a plurality of first internal electrodes 3 a and a plurality of second internal electrodes 3 b are alternately arranged in the stacked body 2 along the stacking direction. Thereby, the plurality of first internal electrodes 3a and the plurality of second internal electrodes 3b are insulated from each other.

  As shown in FIGS. 2A and 3, one end of the plurality of first internal electrodes 3 a is drawn out to the second end face 2 f. The plurality of first internal electrodes 3a are arranged at equal intervals in the stacking direction of the capacitor 1 so as to extend in a direction parallel to the first and second main surfaces 2a, 2b. The first internal electrode 3a does not reach the first and second side surfaces 2c and 2d.

  As shown in FIG. 3, one end of the plurality of second internal electrodes 3b is drawn out to the first end face 2e. The plurality of second internal electrodes 3b are arranged at equal intervals in the stacking direction of the capacitor 1 so as to extend in a direction parallel to the first and second main surfaces 2a, 2b. The second internal electrode 3b does not reach the first and second side surfaces 2c and 2d.

  The internal electrode 3 is formed between 20 and 2000 layers between the dielectric layers 5 of the laminate 2. Examples of the material of the internal electrode 3 include metals such as Ni, Cu, Ag, Pd, and Au, or alloys such as an Ag—Pd alloy containing one or more of these metals. All the internal electrodes 3 are preferably formed of the same metal or alloy.

  The overall dimensions of the internal electrode 3 are, for example, 0.39 to 3.1 mm in the long side direction of the multilayer body 2 in FIG. 2A, and are 0.19 to 1.5 mm, for example, in the short side direction of the multilayer body 2. The thickness of the internal electrode 3 is not particularly limited. The thickness of the internal electrode 3 may be, for example, about 0.3 to 2 μm.

  In the example shown in FIGS. 2A and 5, the first internal electrode 3 a is at least partially divided through the slit 9, and is bent to the second internal electrode side 3 b at a portion adjacent to the slit 9. It has a curved portion 10. The slit 9 is an elongated area where no electrode is formed. A groove or the like that divides the internal electrode 3.

  In the example shown in FIG. 2B, the second internal electrode 3a is also divided at least partially via the slit 9 and is located on the first internal electrode side 3a at a portion adjacent to the slit 9. It has a bent portion 10. The length of the curved portion 10 is about 0.1 to 4 μm.

  As shown in FIG. 2A, since the internal electrode 3 is at least partially divided through the slit 9, it is a region where the first and second internal electrodes 3a and 3b face each other in the stacking direction. The generated electrostrictive stress is divided by the slit 9 and relaxed.

  Further, as shown in FIG. 2B, the curved portion 10 of the first internal electrode 3a and the curved portion 10 of the second internal electrode 3b face each other in the direction intersecting the stacking direction. Therefore, a voltage is applied at the facing portion, and electrostriction occurs. Therefore, this electrostriction cancels the electrostriction in the opposing region in the stacking direction of the first and second internal electrodes 3a, 3b, so that the stress due to electrostriction in the entire capacitor 1 can be suppressed.

  As a result, for example, it is not necessary to use a separate member such as a conventional terminal member, so that the electronic device 7 having the capacitor 1 for noise reduction can be reduced in height.

  The above operation will be described below with reference to FIG. In the conventional internal electrode shown in FIG. 4A, the entire region L1 expands and contracts due to electrostriction. On the other hand, in the internal electrode 3 in the example shown in FIG. 4B, the region that expands and contracts due to electrostriction is divided into L <b> 2 and L <b> 3 by the slit 9. Therefore, the slit 9 suppresses expansion and contraction due to electrostriction of the entire internal electrode 3.

  The suppression of stress due to electrostriction is also apparent when viewed from the longitudinal section of the laminate 2. Here, this will be described in detail with reference to FIG. As in the example shown in FIG. 2B, the internal electrodes 3 are arranged in the stacking direction. Therefore, the slits 9 shown in FIG. 2A are arranged in the stacking direction. Here, in the example shown in FIG. 5, the internal electrode part 31 and the internal electrode part 33 are part of the second internal electrode 3b, and the internal electrode part 32 and the internal electrode part 34 are part of the first internal electrode 3a. is there. A voltage is applied in the stacking direction between the internal electrode unit 31 and the internal electrode unit 32 adjacent in the stacking direction. Similarly, a voltage is also applied in the stacking direction between the internal electrode part 33 and the internal electrode part 34 adjacent in the stacking direction. On the other hand, a voltage is applied between the internal electrode portion 31 and the internal electrode portion 34 in a direction crossing the stacking direction. Similarly, a voltage is applied between the internal electrode portion 33 and the internal electrode portion 32 in a direction crossing the stacking direction. Therefore, a voltage is applied between the first and second internal electrodes 3a and 3b in the direction intersecting the stacking direction and in the stacking direction.

  Furthermore, since the curved portions 3d of the internal electrode portion 31 and the internal electrode portion 34 face each other through the slit 9, the facing area of both can be increased. Similarly, the facing area between the internal electrode portion 33 and the internal electrode portion 32 can be increased. Therefore, the electrostriction in the direction crossing the stacking direction can be further increased.

  Therefore, the expansion and contraction due to electrostriction occurring in the direction intersecting the stacking direction and the expansion and contraction due to electrostriction occurring in the stacking direction cancel each other. Therefore, the expansion and contraction due to electrostriction can be suppressed in the entire capacitor 1.

  The capacitor 1 having the above configuration is manufactured by a ceramic green sheet lamination method as described below.

  Specifically, a plurality of green sheets to be the dielectric layer 5 are prepared. In this step, the ceramic green sheet is obtained by preparing a slurry-like ceramic slurry by adding an appropriate organic solvent or the like to the ceramic raw material powder and mixing it, and then molding the slurry by a doctor blade method or the like.

  Next, the internal electrode 3 is formed on the green sheet. In this step, a conductive material to be a pattern of the internal electrode 3 is formed on the obtained ceramic green sheet by screen printing or the like. In addition, the pattern of the several internal electrode 3 is printed on this one green sheet so that many capacitors can be obtained from one green sheet.

Next, after laminating and pressing a plurality of ceramic green sheets, a raw laminated body in which many pieces are integrated is produced. This laminated body is cut to obtain a raw body of the capacitor 1 as a single laminated body. Here, when pressing is performed, a pressing plate having a convex portion having a width approximately equal to or smaller than the width of the slit 9 is used. As shown in FIG. 6, the pressing plate 8 is pressed against at least one of the upper surface and the lower surface of the laminate so that the position of the convex portion 8 a matches the position of the slit 9. By such a press, it is possible to form curved portions 3d that are bent in the stacking direction at the edge portions on both sides of the slit 9. In addition, it is preferable to make the height of the convex part 8a of the pressing plate 8 smaller than the interval between the internal electrodes 3 so that the adjacent internal electrodes 3 do not contact each other.

  In addition to the pressing plate 8, pressing may be performed using hydrostatic pressure. For example, a bag whose surface is made of rubber may be filled with liquid, and this may be pressed against at least one of the upper surface or the lower surface of the laminate.

  When one of the upper surface and the lower surface of the laminated body is pressed by the pressing plate 8 or a hydrostatic pressure press, all the curved portions 10 are laminated as shown in FIG. Bend uniformly toward the other side of. In addition, when both the upper surface and the lower surface of the laminated body are pressed by the pressing plate 8 or a hydrostatic pressure press, the bent portion 10 does not occur in the central portion of the laminated body, and the upper surface side of the laminated body And the curved part 10 arises in the lower surface side. The bent portion 10 on the upper surface side is bent to the lower surface side, and the bent portion 10 on the lower surface side is bent to the upper surface side.

Next, the capacitor body 1 in a raw state is fired to obtain a laminate 2. In this step, for example, the laminate 2 is obtained by baking at 800 to 1050 ° C. By this step, the green sheet becomes the dielectric layer 6 and the conductive material becomes the internal electrode 3.

  Next, the external electrode 4 is formed by applying a conductive paste to both ends of the laminate 2 and baking it. The external electrode 4 may be formed by a thin film forming method such as vapor deposition, plating, or sputtering.

  The material of the external electrode 4 thus obtained may be a metal material such as silver, nickel, palladium, or an alloy thereof other than copper.

  Next, a plating layer 2b such as a nickel (Ni) plating layer, a gold (Au) plating layer, a tin (Sn) plating layer, or a solder plating layer is formed on the surface of the obtained external electrode 4 as necessary. , Capacitor 1 is obtained.

  The present invention is not limited to the embodiments described above, and various changes and improvements can be made without departing from the scope of the present invention.

  For example, the laminate 2 may be chamfered to form a rounded portion. By this step, it is possible to prevent microcracks from being removed and chipped in the rounded portion of the obtained laminate 2. Furthermore, the barrel polishing has an effect of removing the surface oxide film of the metal particles and exposing the metal surface to improve the plating adhesion.

Further, in the example shown in FIG. 2B, both the first and second internal electrodes 3a and 3b have the slit 9 and the curved portion 10, but the slit 9 and the curved portion 10 are provided. Only the first internal electrode 3a may be used. Even in this case, the electrostrictive stress generated in the region where the first and second internal electrodes 3a and 3b are opposed to each other in the stacking direction can be divided and relaxed. Even in this case, the curved portion 10 of the first internal electrode 3a and the second internal electrode 3b face each other in the direction crossing the stacking direction. Therefore, a voltage is applied to the opposing portions, electrostriction is generated, and the electrostriction in the opposing region in the stacking direction of the first and second internal electrodes 3a and 3b can be canceled.

  Further, as shown in FIG. 2A, the internal electrode 3 has a rectangular shape, and the slit 9 extends in the length direction of the internal electrode 3 so as to reach at least one side 11 of the internal electrode 3. . Here, the length direction is the long side direction of the stacked body 2 and is a direction connecting the first and second external electrodes 4a and 4b. With such a configuration, the area of the region divided by the slit 9 is increased. Therefore, the slit 9 is preferable because expansion and contraction due to electrostriction in the width direction of the internal electrode 3 can be greatly suppressed.

In addition, as in the example shown in FIG.
312 and the plurality of regions 311 and 312 preferably have the same area.
With such a configuration, electrostriction generated in the width direction of the internal electrode 3 becomes uniform. Therefore, since the stress due to electrostriction does not concentrate in one place in the entire capacitor 1, it is possible to provide a capacitor that disperses vibrations, does not squeeze the substrate, and is difficult to break.

  Further, as in the example shown in FIG. 7A, the region 3A where the first and second internal electrodes 3a, 3b are opposed is divided by the slit 9, and the slit 9 is another electrode opposed from one side of the electrode facing region 3A. It is preferable to extend to the side. With such a configuration, a region where electrostriction occurs can be completely divided, and electrostriction in the width direction of the internal electrode 3 can be further suppressed.

  Further, as in the example shown in FIG. 7B, it is preferable that the internal electrode 3 reaches the other side 12 where the slit 9 faces the side 11. With such a configuration, the internal electrode 3 is completely separated. Therefore, electrostriction in the width direction of the internal electrode 3 can be further suppressed.

Further, as in the example shown in FIG. 7B, a plurality of regions 313 divided by the slits 9 are provided.
, 314 preferably have the same area. With such a configuration, the internal electrode 3
The electrostriction that occurs in the width direction is uniform. Therefore, since the stress due to electrostriction does not concentrate in one place in the entire capacitor 1, it is possible to provide a capacitor that disperses vibrations, does not squeeze the substrate, and is difficult to break.

  Further, as in the example shown in FIG. 7C, the slit 9 may extend in the width direction of the internal electrode 3 so as to reach at least one side 13 of the internal electrode 3. Here, the width direction is a short side direction of the multilayer body 2 and is a direction orthogonal to a direction connecting the first and second external electrodes 4a and 4b. With such a configuration, electrostriction in the long side direction of the stacked body 2 can be divided. Here, since the electrostriction of the capacitor 1 is relatively large in the long side direction of the multilayer body 2, it is preferable that the electrostriction in this direction can be divided.

Further, as in the example shown in FIG. 7C, a plurality of regions 315 divided by the slits 9 is obtained.
316 preferably have the same area. Here, in FIG. 7C, it is preferable that the divided regions 315 and 316 have the same area in the electrode facing region 3A excluding the entire electrode 3 but not the electrode non-facing region 3B. With such a configuration, electrostriction generated in the length direction of the internal electrode 3 becomes uniform. Therefore, since the stress due to electrostriction does not concentrate in one place in the entire capacitor 1, it is possible to provide a capacitor that disperses vibrations, does not squeeze the substrate, and is difficult to break.

  In addition, it is preferable that the slit 9 is provided with two or more like the example shown to Fig.8 (a). With such a configuration, a region where electrostriction does not occur can be further provided. Therefore, it is preferable because electrostriction of the entire capacitor 1 can be further suppressed.

Further, as in the example illustrated in FIG. 8B, it is preferable that the slit 9 is a mixture of the slit 9 extending in the length direction and the slit 9 extending in the width direction. According to such a configuration, the electrostriction in the width direction and the length direction of the internal electrode 3 can be suppressed at the same time. Therefore, electrostriction of the entire capacitor 1 can be suppressed.

  Further, as in the example shown in FIG. 9, the slits 9 are mixed with those extending in the length direction and those extending in the width direction, and the electrode facing region 3 </ b> A has the same area by the slits 9. It is preferable to be divided into a plurality of regions 317 to 320 so as to be. With such a configuration, electrostriction generated in the length direction and width direction of the internal electrode 3 becomes uniform. Therefore, since the stress due to electrostriction does not concentrate in one place in the entire capacitor 1, it is possible to provide a capacitor that disperses vibrations, does not squeeze the substrate, and is difficult to break.

  Further, as in the example shown in FIG. 10, the first external electrode 4a and the second external electrode 4b may be provided only on the second main surface 2b. In this case, as shown in FIG. 10, the first lead electrode 15 a and the second lead electrode 15 b as through conductors connected to the first internal electrode 3 a and the second internal electrode 3 b, respectively, in the multilayer body 2. Is provided. The first extraction electrode 15a and the second extraction electrode 15b are connected to the first external electrode 4a and the second external electrode 4b at the second main surface 2b.

  In the example shown in FIG. 11, the first internal electrode 3a and the second internal electrode 3b have one and the other end portions 31a, 32a, 31b, 32b adjacent to the slit 9, and the first internal electrode The slit 9 of 3a and the slit 9 of the second internal electrode 3b are provided at corresponding positions in plan view, and one end 31a of the first internal electrode 3a is bent toward the second internal electrode 3b. At the same time, one end 31a of the first internal electrode 3a is located on the other end 32a side of the second internal electrode 3b, which is directly below the end 31a.

  In such a case, as will be described later, since the curved portion 10 of one end 31a of the first internal electrode 3a can be lengthened, the one end 31a of the first internal electrode 3a and the second internal electrode 3b The facing area between the curved portions 10 can be increased with the other end portion 32b. As a result, the electrostriction in the direction crossing the stacking direction can be further increased. Therefore, the expansion and contraction due to electrostriction occurring in the direction crossing the stacking direction and the expansion and contraction due to electrostriction occurring in the stacking direction further cancel each other. Therefore, expansion and contraction due to electrostriction can be further suppressed in the entire capacitor 1.

  Note that the slits 9 of the first internal electrode 3a and the second internal electrode 3b are provided at positions corresponding to each other when seen in a plan view. It means that it may be.

  In the example shown in FIG. 11, one end 31a of the first internal electrode 3a is longer than the one end 31b of the second internal electrode 3b. In such a configuration, as shown in FIG. 12, one end 31a of the first internal electrode 3a is positioned closer to the other end 32a than the one end 31b of the second internal electrode 3b. -It can be manufactured by pressure bonding. That is, one end 31a of the first internal electrode 3a is easily bent downward because the second internal electrode 3b does not exist immediately below it.

  Further, as in the example illustrated in FIG. 13, one end 31 b of the second internal electrode 3 b may not have the curved portion 10. Even in such a case, as described above, the curved portion 10 of the one end portion 31a can be enlarged in the stacking process.

  Further, as in the example shown in FIG. 14, the other end 32b of the second internal electrode 3b is bent toward the first internal electrode 3a, and the other end 32b of the second internal electrode 3b It is located on the side of one end 31b from the other end 32a of the first internal electrode 3a immediately below the end 32b.

  In such a case, as described later, the curved portion 10 of the other end portion 32b of the second internal electrode 3b can be lengthened. Therefore, as in the example shown in FIG. 14, both of the curved portions 10 at one end 31a of the first internal electrode 3a and the other end 32b of the second internal electrode 3b can be enlarged. Therefore, the facing area between the curved portions 10 of the first internal electrode 3a and the second internal electrode 3b can be increased. As a result, the electrostriction in the direction crossing the stacking direction can be further increased. Therefore, the expansion and contraction due to electrostriction occurring in the direction crossing the stacking direction and the expansion and contraction due to electrostriction occurring in the stacking direction further cancel each other. Therefore, expansion and contraction due to electrostriction can be further suppressed in the entire capacitor 1.

  In the example shown in FIG. 14, the other end portion 32b of the second internal electrode 3b has a curved portion 10 longer than the other end portion 32a of the first internal electrode 3a. Also in such a configuration, as shown in FIG. 12, the other end 32b of the second internal electrode 3b is positioned closer to the one end 31b than the other end 32a of the first internal electrode 3a. -It can be manufactured by pressure bonding.

  Further, as in the example shown in FIG. 15, the other end portion 32 a of the first internal electrode 3 a may not have the curved portion 10. Even in such a case, the curved portion 10 at the other end portion 32b of the second internal electrode 3b can be enlarged in the step of laminating and crimping as described above. Therefore, both of the bent portions 10 at one end 31a of the first internal electrode 3a and the other end 32b of the second internal electrode 3b can be enlarged. Therefore, the facing area between the curved portions 10 can be increased, and the electrostriction in the direction intersecting the stacking direction can be further increased.

  Note that the embodiments in FIGS. 11 to 15 described above may be combined with each other to constitute another form.

1: Capacitor 2: Laminated body 3: Internal electrode 4: External electrode 5: Dielectric layer 6: Wiring board 7: Electronic device 9: Slit 10: Curved part
31a: One end of the first internal electrode 3a
32a: The other end of the first internal electrode 3a
31b: One end of the second internal electrode 3b
32b: the other end of the second internal electrode 3b

Claims (9)

A laminate in which a plurality of dielectric layers are laminated;
A first internal electrode and a second internal electrode provided between the dielectric layers so as to face each other through the dielectric layer;
An internal electrode comprising the first internal electrode and the second internal electrode;
The capacitor is characterized in that the first internal electrode is at least partially divided through a slit, and has a curved portion bent toward the second internal electrode at a portion adjacent to the slit.   The said 2nd internal electrode is at least partially parted through the slit, and has the curved part bent to the said 1st internal electrode side in the site | part adjacent to the said slit. Capacitor.   The internal electrode has a rectangular shape, and the slit extends in the length direction of the internal electrode so as to reach at least one side of the internal electrode. The capacitor described.   The capacitor according to claim 3, wherein the internal electrode has the slit reaching another side opposite to the one side.   The internal electrode has a rectangular shape, and the slit extends in the width direction of the internal electrode so as to reach at least one side of the internal electrode. Capacitor.   The capacitor according to claim 1, wherein the internal electrode is divided into a plurality of regions by the slit, and the plurality of regions have the same area.   The capacitor according to claim 2, wherein the slit of the first internal electrode and the slit of the second internal electrode are provided at corresponding positions in plan view.   The capacitor according to claim 1, further comprising a first extraction electrode and a second extraction electrode connected to the first internal electrode and the second internal electrode, respectively. The capacitor according to claim 1, further comprising a first external electrode and a second external electrode that are electrically connected to the first internal electrode and the second internal electrode, respectively.
A wiring board provided with electrode pads on the main surface;
The electronic device is characterized in that the capacitor is mounted on the main surface of the wiring board by electrically connecting the first external electrode and the second external electrode to the electrode pad.

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