JP2009021280A - Multilayer capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multilayer capacitor which is made lower in ESL. <P>SOLUTION: Center intervals b1 and b3 of lead-out portions 14a and 15a of first and second internal conductor layers 14 and 15 constituting respective independent capacitor portions are made narrower than a center interval b2 of lead-out portions 14a and 15b of first and second internal conductor layers 14 and 15 which are most adjacent of an adjacent independent capacitor portion, and thus the length of a current path from the lead-out portion 14a of one polarity to the lead-out portion 15a of the other polarity is made to be short to lower inductance generated on the current path. Further, the lead-out portion 14a of the one polarity is put closer to the lead-out portion 15a of the other polarity to effectively achieve magnetic field canceling operation obtained with currents flowing to the lead-out portions 14a and 15a in opposite directions. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a multilayer capacitor suitable for decoupling applications.

  A multilayer capacitor used for decoupling requires high capacitance and low ESL (equivalent series inductance). Patent Documents 1 and 2 disclose this type of multilayer capacitor.

  The multilayer capacitor disclosed in Patent Document 1 includes a rectangular parallelepiped main body and a total of eight external electrodes that are provided in a non-contact manner on each of both sides in the width direction of the main body and have four different polarities. The main body has a first inner conductor layer having a total of four lead portions provided on each side edge in the width direction and a total of four lead portions provided on each side edge in the width direction. It has a structure in which the second inner conductor layers having positions different from the lead portions of the one inner conductor layer are alternately laminated and integrated through the dielectric layers. The four lead portions of each first inner conductor layer are connected to four external electrodes of one polarity, and the four lead portions of each second inner conductor layer are connected to the remaining four external electrodes of the other polarity. ing.

On the other hand, the multilayer capacitor disclosed in Patent Document 2 has a structure in which each first inner conductor layer of the multilayer capacitor disclosed in Patent Document 1 is divided into two in the width direction and each second inner conductor layer is divided in two in the width direction. Yes.
Special table 2002-508114 gazette JP 2002-151349 A

  Since the capacitance of the multilayer capacitor can be basically adjusted by the number of laminated inner conductor layers, both of the multilayer capacitors disclosed in Patent Document 1 and Patent Document 2 can obtain sufficient capacitance suitable for decoupling applications. Can do.

  On the other hand, the ESL of the multilayer capacitor is determined by the overall structure of the multilayer capacitor. However, in the multilayer capacitors of Patent Document 1 and Patent Document 2, the direction of the current flowing through the different-polarity lead-out portions through the dielectric layer is determined. By making it reverse, the magnetic field generated by the current flowing through each lead-out portion is canceled out to reduce ESL.

  The ESL reduction method employed in the multilayer capacitors disclosed in Patent Document 1 and Patent Document 2 is to reduce the inductance generated in the current path from the one polarity lead portion to the other polarity lead portion by the magnetic field canceling action. If the length of the current path from the one-polarity lead part to the other-polarity lead part is shortened to reduce the inductance that can occur in the current path, the ESL can be further reduced. If the lead portion and the other polarity lead portion are brought close to each other so that the magnetic field canceling action can be effectively performed, the ESL can be further reduced.

  The present invention was created in view of the above circumstances, and an object of the present invention is to provide a multilayer capacitor in which ESL is further reduced.

  To achieve the above object, the present invention provides a multilayer capacitor in which a first external electrode having one polarity and a second external electrode having the other polarity are alternately provided in a non-contact manner on a side surface of a rectangular parallelepiped body. A plurality of first inner conductor layers arranged in a non-contact manner on the same plane and the same number of second inner conductor layers as the first inner conductor layers arranged in a non-contact manner on the same plane are alternately stacked via dielectric layers. A plurality of independent capacitor portions are constituted by the first and second internal electrode layers arranged in the stacking direction via the dielectric layers, and the first and second inner capacitor portions are respectively The second inner conductor layer has one lead portion at a different position on the same side edge, the lead portion of the first inner conductor layer of each independent capacitor portion is connected to the first outer electrode, and the second The lead portion of the inner conductor layer is connected to the second outer electrode adjacent to the first outer electrode. The center intervals of the lead portions of the first and second inner conductor layers of each independent capacitor portion are connected to each other. It is characterized by being narrower than the center interval of the parts.

  According to the multilayer capacitor, the center interval of the lead portions of the first and second inner conductor layers of each independent capacitor portion is set so that the lead portions of the first and second inner conductor layers that are closest to each other in the adjacent independent capacitor portion. By making the center interval smaller than the center interval, the length of the current path from the one polarity lead portion to the other polarity lead portion can be shortened, and the inductance that can be generated in the current path can be reduced. The lead portion and the lead portion with the other polarity can be brought close to each other to effectively perform the magnetic field canceling action obtained by the current flowing in the reverse direction to the lead portion, thereby further reducing the ESL of the multilayer capacitor.

  According to the present invention, it is possible to provide a multilayer capacitor in which ESL is further reduced.

  The above object and other objects, structural features, and operational effects of the present invention will become apparent from the following description and the accompanying drawings.

[First Embodiment]
1 to 3 show a first embodiment of the present invention (multilayer capacitor). FIG. 1 is a perspective view of the multilayer capacitor, FIG. 2 is a cross-sectional view of the multilayer capacitor shown in FIG. 1, and FIG. FIG. 2 is a perspective view showing a layer configuration of a main body shown in FIG.

  The multilayer capacitor 10 according to the first embodiment includes a rectangular parallelepiped main body 11 having a predetermined length, width, and height, and a first polarity first provided alternately in a non-contact manner on both side surfaces of the main body 11 in the width direction. An external electrode 12 and a second external electrode 13 having the other polarity are provided.

  Two first external electrodes 12 and two second external electrodes 13 are provided on each side surface in the width direction of the main body 11, and a total of four first, first and second external electrodes 12 are provided on one side surface (the right side surface in FIG. 1). The second external electrodes 12, 13 are arranged in the order of the first external electrode 12, the second external electrode 13, the first external electrode 12, and the second external electrode 13 from the left, and the other side surface of the main body 11 (the left side surface in FIG. 1). ), A total of four first and second external electrodes 12 and 13 are arranged from the left so as to face the first and second external electrodes 12 and 13 on one side surface. The two external electrodes 13 and the first external electrode 12 are arranged in this order.

  The main body 11 includes two first inner conductor layers 14 arranged in a non-contact manner on the same plane, and the same number of second inner conductor layers 15 as the first inner conductor layers 15 arranged in a non-contact manner on the same plane. It has the structure which laminated | stacked alternately and integrated. Each of the first inner conductor layers 14 and each of the second inner conductor layers 15 has a substantially rectangular shape, and is arranged in a non-contact manner in the same plane as the two first inner conductor layers 14 arranged in a non-contact manner in the same plane. The two second inner conductor layers 15 face each other in the stacking direction via the dielectric layer DL. In other words, in the main body 11, two independent capacitor portions (not indicated) are spaced in the length direction by the first and second internal electrode layers 14 and 15 arranged in the stacking direction via the dielectric layer DL. It is configured.

  Each first inner conductor layer 14 has one lead portion 14a on one side edge in the width direction (right side edge in FIG. 3) and the other side edge in the width direction (left side edge in FIG. 3). The conductor layer 15 has one lead portion 14a on one side edge in the width direction (right side edge in FIG. 3) and the other side edge in the width direction (left side edge in FIG. 3). The lead portion 14a of each first inner conductor layer 14 and the lead portion 15a of each second inner conductor layer 15 form a substantially rectangular shape, and the two first inner conductor layers 14 are arranged in a non-contact manner on the same plane. The positions of the lead portions 15a of the two second inner conductor layers 15 arranged in a non-contact manner in the same plane as the positions of the lead portions 14a differ in the length direction and do not face each other in the stacking direction.

  As shown in FIG. 2, the lead-out portion 14a on one side edge (upper edge in FIG. 2) of each first internal electrode layer 14 constituting one independent capacitor portion (capacitor portion configured on the left side in FIG. 2) Connected to the first external electrode 12 located on the leftmost side of one side surface (upper side surface in FIG. 2) of the main body 11, the lead-out portion 14a on the other side edge (lower side edge in FIG. 2) is connected to the other side surface (see FIG. 2 is connected to the first external electrode 12 located second from the left. In addition, the lead-out portion 15a at one side edge (upper edge in FIG. 2) of each second internal electrode layer 15 constituting one independent capacitor portion (capacitor portion configured on the left side in FIG. Connected to the second external electrode 13 located second from the left (upper side surface in FIG. 2), the lead portion 15a at the other side edge (lower side edge in FIG. 2) is connected to the other side surface of the main body 11 (lower side in FIG. The second external electrode 13 located on the leftmost side of the side surface is connected.

  The lead-out portion 14a at one side edge (upper edge in FIG. 2) of each first internal electrode layer 14 constituting the other independent capacitor portion (capacitor portion configured on the right side in FIG. 2) is one side surface (FIG. 2). 2 is connected to the first external electrode 12 located third from the left of the second outer surface (the upper side surface of FIG. 2), and the lead-out portion 14a of the other side edge (the lower side edge of FIG. 2) is the other side surface (the lower side surface of FIG. 2). Is connected to the first external electrode 12 located fourth from the left. Further, the lead-out portion 15a at one side edge (upper edge in FIG. 2) of each second internal electrode layer 15 constituting one independent capacitor portion (capacitor portion configured on the right side in FIG. 2) is one side surface of the main body 11. Connected to the second external electrode 13 located fourth from the left (upper side surface in FIG. 2), the leading portion 15a at the other side edge (lower side edge in FIG. 2) is connected to the other side surface of the main body 11 (lower side in FIG. 2). The second external electrode 13 located third from the left side surface is connected.

  As shown in FIG. 2, a total of four first and second external electrodes 12 and 13 (two first external electrodes 12 and two first external electrodes 12 and two pieces provided on one side surface (upper side surface in FIG. 2) of the main body 11 are provided. In the second external electrode 13), the center intervals a1 to a3 of the first and second external electrodes 12 and 13 adjacent to each other are all equal.

  The center intervals b1 and b3 of the lead portions 14a and 15a of the first and second inner conductor layers 14 and 15 constituting each independent capacitor portion are the first and second adjacent ones in the adjacent independent capacitor portions. It is narrower than the center distance b2 of the lead portions 14a, 15a of the inner conductor layers 14, 15. Moreover, the center intervals b1 and b3 are narrower than the center intervals a1 to a3, and the center interval b2 is wider than the center intervals a1 to a3.

  Although illustration of dimension lines and the like is omitted, the center distance between the first and second external electrodes 12 and 13 on the other side of the main body 11 (the lower side of FIG. 2) and the first and second inner conductor layers 14 and 15 are omitted. The center distance between the leading portions 14a and 15a is the same as described above.

  The variable range when the center distances b1 and b3 are reduced depends on the difference between the widths of the first and second external electrodes 12 and 13 and the lead portions 14a and 15a. FIG. 2 shows an example in which the center intervals b1 and b3 are narrowed to the maximum value of the variable range, but the center intervals b1 and b3 are not necessarily narrowed to the maximum value of the variable range.

  In the above-described multilayer capacitor 10, the length of the current path from the one polarity lead portion 14a to the other polarity lead portion 15a is shortened by making the center intervals b1 and b3 narrower than the center interval b2. In addition, the inductance that can be generated in the current path can be reduced, and the magnetic field obtained by the current flowing in the opposite direction to the lead portions 14a and 15a by bringing the lead portion 14a of one polarity close to the lead portion 15a of the other polarity. The canceling action can be effectively performed, whereby the ESL of the multilayer capacitor 10 can be further reduced.

  Incidentally, according to an experiment, in the multilayer capacitor in which each of the lead portions 14a and 15a has a width of 150 μm and a length of 125 μm, the center intervals a1 to a3 are set to 500 μm, the center intervals b1 and b3 are set to 400 μm, and the center interval b2 is set to 600 μm. In this case, it is added that the ESL can be lowered by about 5 pH compared to the case where the center intervals a1 to a3 are set to 500 μm and the center intervals b1 to b3 are set to 500 μm.

[Second Embodiment]
4 to 6 show a second embodiment of the present invention (multilayer capacitor). FIG. 4 is a perspective view of the multilayer capacitor, FIG. 5 is a cross-sectional view of the multilayer capacitor shown in FIG. 4, and FIG. 5 is a perspective view showing a layer configuration of a main body shown in FIG.

  The multilayer capacitor 20 of the second embodiment includes a rectangular parallelepiped main body 21 having a predetermined length, width, and height, and a first polarity first provided alternately in a non-contact manner on both side surfaces of the main body 21 in the width direction. An external electrode 22 and a second external electrode 23 having the other polarity are provided.

  Two first external electrodes 22 and two second external electrodes 23 are provided on each side surface in the width direction of the main body 21, and a total of four first, first and second external electrodes 22 are provided on one side surface (the right side surface in FIG. 4). The second external electrodes 22, 23 are arranged in the order of the first external electrode 22, the second external electrode 23, the first external electrode 22, and the second external electrode 23 from the left, and the other side surface of the main body 21 (the left side surface in FIG. 4). ), A total of four first and second external electrodes 22 and 23 from the left face the first and second external electrodes 22 and 23 on one side. The two external electrodes 23 and the first external electrode 22 are arranged in this order.

  The main body 21 includes two first inner conductor layers 24 arranged in a non-contact manner on the same plane, and the same number of second inner conductor layers 25 as the first inner conductor layers arranged in a non-contact manner on the same plane. It has the structure which laminated | stacked alternately and integrated. Each first inner conductor layer 24 and each second inner conductor layer 25 have a rectangular shape of almost the same size, and are arranged in a non-contact manner on the same plane with two first inner conductor layers 24 arranged in a non-contact manner on the same plane. The two second inner conductor layers 25 face each other in the stacking direction via the dielectric layer DL. In other words, in the main body 21, two independent capacitor portions (not shown) are spaced in the length direction by the first and second internal electrode layers 24 and 25 arranged in the stacking direction via the dielectric layer DL. It is configured.

  Each first inner conductor layer 24 has one lead portion 24a on one side edge in the width direction (right side edge in FIG. 6) and the other side edge in the width direction (left side edge in FIG. 6). The conductor layer 25 has one lead portion 24a on one side edge in the width direction (right side edge in FIG. 6) and the other side edge in the width direction (left side edge in FIG. 6). The lead portion 24a of each first inner conductor layer 24 and the lead portion 25a of each second inner conductor layer 25 form a rectangular shape having substantially the same size, and are arranged in a non-contact manner on the same plane. The positions of the lead portions 25a of the two second inner conductor layers 25 arranged in a non-contact manner in the same plane as the positions of the lead portions 24a are different in the length direction and are not facing each other in the stacking direction.

  As shown in FIG. 5, the lead-out portion 24a on one side edge (upper edge in FIG. 5) of each first internal electrode layer 24 constituting one independent capacitor portion (capacitor portion configured on the left side in FIG. 5) Connected to the first external electrode 22 located on the leftmost side of one side surface (upper side surface in FIG. 5) of the main body 21, the lead-out portion 24 a on the other side edge (lower side edge in FIG. 5) 5 is connected to the first external electrode 22 located second from the left. In addition, a lead portion 25a at one side edge (upper edge in FIG. 5) of each second internal electrode layer 25 constituting one independent capacitor portion (capacitor portion configured on the left side in FIG. Connected to the second external electrode 23 located second from the left (upper side surface in FIG. 5), the leading portion 25a at the other side edge (lower side edge in FIG. 5) is connected to the other side surface of the main body 21 (lower side in FIG. 5). The second external electrode 23 located on the leftmost side) is connected.

  The lead portion 24a at one side edge (upper edge in FIG. 5) of each first internal electrode layer 24 constituting the other independent capacitor portion (capacitor portion configured on the right side in FIG. 5) is one side surface (FIG. 5). 5 is connected to the first external electrode 22 located third from the left on the left side, and the lead-out portion 24a of the other side edge (lower side edge in FIG. 5) is the other side surface of the main body 21 (lower side surface in FIG. 5). Are connected to the first external electrode 22 located fourth from the left. In addition, the lead portion 25a at one side edge (upper edge in FIG. 5) of each second internal electrode layer 25 constituting one independent capacitor portion (capacitor portion configured on the right side in FIG. It is connected to the second external electrode 23 located fourth from the left (upper side surface in FIG. 5), and the leading portion 25a at the other side edge (lower side edge in FIG. 5) is connected to the other side surface of the main body 21 (lower side in FIG. 5). The second external electrode 23 located third from the left of the side surface is connected.

  As shown in FIG. 5, a total of four first and second external electrodes 22, 23 (two first external electrodes 22 and two pieces provided on one side surface (upper side surface in FIG. 5)) of the main body 21. Out of the center intervals a1 to a3 of the first and second outer electrodes 22 and 23 adjacent to each other in the second outer electrode 23), the lead portions 24a of the first and second inner conductor layers 24 and 25 constituting the independent capacitor portions. , 25a connected to each other, the center distances a1 and a3 of the first and second external electrodes 22 and 23 are in the adjacent independent capacitor portions and the lead portions 24a of the first and second inner conductor layers 24 and 25 that are the most adjacent. , 25a is narrower than the center interval a2 of the first and second external electrodes 23, 24 connected thereto.

  Further, the center intervals b1 and b3 of the lead portions 24a and 25a of the first and second inner conductor layers 24 and 25 constituting each independent capacitor portion are the first and second adjacent ones in the adjacent independent capacitor portions. It is narrower than the center interval b2 of the lead portions 24a, 25a of the inner conductor layers 24, 25. In addition, the center intervals b1 and b3 are narrower than the center intervals a1 and a3, and the center interval b2 is wider than the center interval a2.

  Although illustration of dimension lines and the like is omitted, the center distance between the first and second external electrodes 22 and 23 on the other side of the main body 21 (the lower side of FIG. 5) and the first and second inner conductor layers 24 and 25 are omitted. The distance between the centers of the leading portions 24a and 25a is the same as described above.

  The center intervals a1 to a3 can be varied within a range that falls within a tolerance of a standard value determined for each multilayer capacitor. Further, the variable range when the center distances b1 and b3 are narrowed depends on the difference between the widths of the first and second external electrodes 22 and 23 and the lead portions 24a and 25a. FIG. 5 shows an example in which the center intervals b1 and b3 are narrowed to the maximum value of the variable range, but the center intervals b1 and b3 are not necessarily narrowed to the maximum value of the variable range.

  In the above-described multilayer capacitor 20, the length of the current path from the one polarity lead portion 24a to the other polarity lead portion 25a is shortened by making the center intervals b1 and b3 narrower than the center interval b3. In addition, the inductance that can be generated in the current path can be reduced, and the magnetic field obtained by the current flowing in the opposite direction to the lead portions 24a and 25a by bringing the lead portion 24a of one polarity close to the lead portion 15a of the other polarity. The canceling action can be effectively performed, whereby the ESL of the multilayer capacitor 20 can be further reduced.

  Further, since the center intervals b1 and b3 can be made narrower by making the center intervals a1 and a3 narrower than the center interval a2, the current from the one polarity lead portion 24a to the other polarity lead portion 15a. By reducing the length of the path, the inductance that can be generated in the current path can be further reduced, and the one-polarity lead portion 24a and the other-polarity lead portion 15a are brought closer to the lead-out portions 24a and 25a. The magnetic field canceling action obtained by the current flowing in the opposite direction can be performed more effectively, and thereby the ESL of the multilayer capacitor 20 can be further reduced.

  Incidentally, according to the experiment, in the multilayer capacitor in which the lead portions 24a and 25a have a width of 150 μm and a length of 125 μm, the center intervals a1 and a3 are 400 μm, the center interval a2 is 00 μm, and the center intervals b1 and b3 are 300 μm. When the center distance b2 is 700 μm, the ESL can be reduced by about 6 pH compared to the case where the center distances a1 to a3 are 500 μm and the center distances b1 to b3 are 500 μm. To do.

The perspective view of the multilayer capacitor which shows 1st Embodiment of this invention FIG. 2 is a transverse cross-sectional view of the multilayer capacitor shown in FIG. 1. It is a perspective view which shows the layer structure of the main body shown in FIG. It is a perspective view of a multilayer capacitor showing a second embodiment of the present invention. FIG. 5 is a cross-sectional view of the multilayer capacitor shown in FIG. 4. It is a perspective view which shows the layer structure of the main body shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Multilayer capacitor, 11 ... Main body, 12 ... 1st external electrode, 13 ... 2nd external electrode, 14 ... 1st internal conductor layer, 14a ... Lead part, 15 ... 2nd internal conductor layer, 15a ... Lead part, DL ... Dielectric layer, 20 ... Multilayer capacitor, 21 ... Main body, 22 ... First external electrode, 23 ... Second external electrode, 24 ... First internal conductor layer, 24a ... Lead-out part, 25 ... Second internal conductor layer, 25a ... leader, DL ... dielectric layer.

Claims (4)

A multilayer capacitor in which a first external electrode having one polarity and a second external electrode having the other polarity are alternately provided in a non-contact manner on a side surface of a rectangular parallelepiped body,
The main body alternately includes a plurality of first inner conductor layers arranged in a non-contact manner on the same plane, and the same number of first inner conductor layers arranged in a non-contact manner on the same plane as the second inner conductor layers via a dielectric layer. A plurality of independent capacitor portions are configured by the first and second internal electrode layers arranged in the stacking direction via the dielectric layer, and having a structure integrated by stacking,
The first and second inner conductor layers of each independent capacitor portion have one lead portion at different positions on the same side edge, and the lead portion of the first inner conductor layer of each independent capacitor portion serves as the first outer electrode. Each connected, and the lead portion of the second inner conductor layer is connected to the second outer electrode adjacent to the first outer electrode,
The center interval between the lead portions of the first and second inner conductor layers of each independent capacitor portion is narrower than the center interval between the lead portions of the first and second inner conductor layers adjacent to each other in the adjacent independent capacitor portion.
A multilayer capacitor characterized by that. Two first external electrodes and two second external electrodes are provided on each side surface in the width direction of the main body,
The number of first internal conductor layers arranged in a non-contact manner on the same plane is 2, the number of second internal conductor layers arranged in a non-contact manner on the same plane is 2, and the number of independent capacitor portions is 2.
One lead-out portion is provided on each side edge in the width direction of the first and second inner conductor layers of each independent capacitor portion, and the lead-out portion on one side edge of the first inner conductor layer of each independent capacitor portion is the main body. The lead portion on the other side is connected to the first external electrode on the other side of the main body, and the lead on the one side edge of the second internal conductor layer of each independent capacitor portion is connected to the first outer electrode on the other side. The part is connected to the second external electrode on one side of the main body, and the lead-out part on the other side edge is connected to the second external electrode on the other side of the main body.
The multilayer capacitor according to claim 1. The center intervals of the first and second external electrodes to which the lead portions of the first and second inner conductor layers of each independent capacitor portion are connected are all equal, and the lead portions of the first and second inner conductor layers of each independent capacitor portion are the same. The center interval of is narrower than the center interval of the first and second external electrodes,
The multilayer capacitor according to claim 1 or 2, wherein The center distance between the first and second external electrodes to which the lead portions of the first and second inner conductor layers of each independent capacitor portion are connected is the first and second inner conductors closest to each other in the adjacent independent capacitor portion. Narrower than the center interval of the first and second external electrodes to which the lead portions of the layers are connected,
The center distance between the lead portions of the first and second internal conductor layers of each independent capacitor portion is the center of the first and second external electrodes to which the lead portions of the first and second internal conductor layers of each independent capacitor portion are connected. Narrower than the interval,
The multilayer capacitor according to claim 1 or 2, wherein

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