JP2018133419A - Multilayer ceramic capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable multilayer ceramic capacitor in which structural defects, such as peeling and crack, are improved.SOLUTION: In a multilayer ceramic capacitor 10 including a laminate 20 formed in rectangular parallelepiped shape by laminating a dielectric layer 40, a first internal electrode 50a, and a second internal electrode 50b, a first external electrode 90a formed on the first end face 26a of the laminate 20 and a second external electrode 90b formed on the second end face 26b of the laminate 20, when viewing the first internal electrode 50a in the T direction, an acute angle αformed by a straight xpassing the end on the first end face 26a side of a first lead-out ramp 76a and extending in the L direction, and the first lead-out ramp 76a is smaller than an acute angle βformed by a straight ypassing the end on the second end face 26b side of a first opposite ramp 66a and extending in the L direction, and the first opposite ramp 66a.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a multilayer ceramic capacitor.

  The multilayer ceramic capacitor includes, for example, a multilayer body formed in a rectangular parallelepiped shape by alternately laminating dielectric layers including barium titanate and the like and internal electrodes including a metal such as nickel, and both end surfaces of the multilayer body And a pair of external electrodes formed. The internal electrodes are stacked so as to be alternately exposed from both end faces of the stacked body, and are electrically connected to each of the pair of external electrodes. In general, the characteristics of a multilayer ceramic capacitor can be deteriorated by moisture entering the multilayer body from between the exposed portion of the internal electrode and the dielectric layer. In addition, there has been a problem that peeling or cracking occurs due to a difference in shrinkage between the internal electrode and the dielectric layer or a difference in expansion caused by a temperature difference between inside and outside of the multilayer ceramic capacitor. Multilayer ceramic capacitors aimed at solving such problems are disclosed in, for example, Patent Document 1 and Patent Document 2.

  In Patent Document 1, by making the width dimension of the lead-out portion of the internal electrode smaller than that of the other portion of the internal electrode (that is, the capacitance forming portion), moisture intrusion from the outside, internal peeling, etc. Multilayer ceramic capacitors that can suppress generation have been proposed. However, when the width dimension of the extraction portion is reduced as in Patent Document 1, the thickness dimension of the internal electrode increases at the corner portion of the capacitance forming portion, the boundary portion between the extraction portion and the capacitance forming portion, or the like. As a result, an internal stress is generated in the laminated body, the thermal shock resistance is lowered, cracks are easily generated, and the characteristics are deteriorated.

  In Patent Document 2, in order to solve the above-described problem of Patent Document 1, an internal electrode having a tapered lead portion that gradually decreases in width as it approaches the end surface of the multilayer body, and a dielectric layer is used. In the pair of internal electrodes facing each other, the internal electrodes are stacked so that the corners of the rectangular portion of one internal electrode are positioned near and outside the tapered portion of the other internal electrode. A structure has been proposed. Thereby, since the multilayer ceramic capacitor of Patent Document 2 can relieve internal stress generated in the multilayer body, structural defects can be improved.

JP-A-8-97071 JP 2004-47536 A

  The inventor paid attention to the corner portion of the rectangular portion of the other internal electrode protruding from the tapered shape portion of one internal electrode when viewed from the stacking direction in the structure of the multilayer ceramic capacitor of Patent Document 2. As a result of earnest research, the inventor has found a problem that structural defects such as peeling and cracking may occur due to stress easily concentrating on the corner portion.

  Therefore, an object of the present invention is to provide a highly reliable multilayer ceramic capacitor in which structural defects such as peeling and cracks are improved.

The multilayer ceramic capacitor according to the present invention is formed in a rectangular parallelepiped shape by laminating a plurality of dielectric layers, a plurality of first internal electrodes, and a plurality of second internal electrodes, and is opposed in the laminating direction. The first main surface and the second main surface, the first side surface and the second side surface facing each other in the width direction orthogonal to the stacking direction, and the first surface facing the length direction orthogonal to the stacking direction and the width direction. A laminated body including the end face and the second end face, a first external electrode electrically connected to the plurality of first internal electrodes by being formed on the first end face, and a second end face And a second external electrode electrically connected to the plurality of second internal electrodes, wherein the first internal electrode is interposed via the dielectric layer. 1st opposing part which opposes 2nd internal electrode And a first drawer portion that is pulled out from the first facing portion to the first end face side and has a smaller dimension in the width direction than the first facing portion, and the first facing portion includes the second In a corner portion where the edge portion located on the end surface side and the edge portion in the width direction cross each other, the first inclining linearly as viewed in the stacking direction so that the dimension in the width direction decreases as the second end surface is approached. The first drawer portion has a width direction dimension that increases toward the first facing portion at a portion of the width direction edge portion on the first facing portion side. The second internal electrode includes a second opposing portion that opposes the first internal electrode via the dielectric layer, and a second opposing portion that is linearly inclined when viewed in the stacking direction. A second drawer portion that is drawn from the opposite portion to the second end face side and has a smaller dimension in the width direction than the second opposite portion. The second facing portion is laminated so that the dimension in the width direction becomes smaller toward the first end surface at the corner portion where the edge portion located on the first end surface side and the edge portion in the width direction intersect. A second opposing inclined portion that inclines in a straight line when viewed in the direction, and the second lead-out portion approaches the second opposing portion at the second opposing portion side portion of the edge in the width direction. Accordingly, it has a second drawer inclined portion that inclines linearly when viewed in the stacking direction so that the dimension in the width direction increases, and when viewed in the stacking direction, the first end face side of the first drawer inclined portion The acute angle formed between the straight line extending through the end of the first portion and along the length direction and the first drawer inclined portion passes through the second end face side end of the first opposing inclined portion and extends in the length direction. The second end face side end portion of the second drawer inclined portion is smaller than the acute angle formed by the straight line extending along the first opposing inclined portion. And an acute angle formed between the straight line extending along the length direction and the second drawer inclined portion extends through the end portion on the first end face side of the second opposing inclined portion and extends along the length direction. It is smaller than the acute angle formed by the straight line and the second opposing inclined portion.
Preferably, when viewed in the stacking direction, the first opposing inclined portion is disposed so as to be located on the inner side in the length direction of the second drawer inclined portion opposed via the dielectric layer, and the first The two opposing inclined portions are disposed so as to be located on the inner side in the length direction of the first drawer inclined portion facing each other through the dielectric layer.
Preferably, when viewed in the stacking direction, the first opposing inclined portion is disposed so as to be positioned on the inner side in the width direction than the second drawer inclined portion, and the second opposing inclined portion is the first It arrange | positions so that it may be located inside the width direction rather than the drawer | drawing-in inclination part.
Preferably, when viewed in the stacking direction, an acute angle formed by a straight line that extends through the end portion on the first end face side of the first drawer inclined portion and along the length direction, and the first drawer inclined portion, and The acute angles formed between the straight line that passes through the end of the second drawer inclined portion on the second end face side and extends along the length direction and the second drawer inclined portion are 45 degrees or more and 60 degrees or less, respectively. .
Preferably, when viewed in the stacking direction, an acute angle formed between a straight line passing through the end portion on the second end face side of the first opposing inclined portion and extending along the length direction, and the first opposing inclined portion, and The acute angles formed between the straight line that passes through the end portion on the first end face side of the second opposing inclined portion and extends along the length direction and the second opposing inclined portion are 55 degrees or more and 70 degrees or less, respectively. .
Preferably, the width direction dimension of the first drawer portion excluding a portion having the first drawer inclined portion as an edge and the second drawer portion excluding a portion having the second drawer inclined portion as an edge portion. Are 60 μm or more and 200 μm or less, respectively.
Preferably, the width direction dimension of the first opposing portion excluding the portion having the first opposing inclined portion as an edge and the second opposing portion excluding the portion having the second opposing inclined portion as an edge. Are 1400 μm or more and 3500 μm or less, respectively.
Preferably, the dimension in the length direction is 1.5 mm or more and 3.4 mm or less, the dimension in the width direction is 0.7 mm or more and 2.7 mm or less, and the dimension in the stacking direction is 0.5 mm or more and 2.7 mm or less. It is.
Preferably, the total number of stacked layers of the first internal electrode and the second internal electrode is 150 or more and 700 or less.

  According to the present invention, it is possible to provide a highly reliable multilayer ceramic capacitor in which structural defects such as peeling and cracks are improved.

  The above-described object, other objects, features, and advantages of the present invention will become more apparent from the following description of embodiments for carrying out the invention with reference to the drawings.

1 is an external perspective view of a multilayer ceramic capacitor according to an embodiment of the present invention. It is sectional drawing along the length direction of the multilayer ceramic capacitor which concerns on one embodiment of this invention. It is sectional drawing along the width direction of the multilayer ceramic capacitor which concerns on one embodiment of this invention. It is the schematic which looked at the 1st internal electrode with which the multilayer ceramic capacitor concerning one embodiment of this invention is provided along the lamination direction. It is the schematic which looked at the 2nd internal electrode with which the multilayer ceramic capacitor concerning one embodiment of this invention is provided along the lamination direction. It is the schematic which looked at the state where the 1st internal electrode with which the multilayer ceramic capacitor concerning one embodiment of this invention is provided, and the 2nd internal electrode were laminated along the lamination direction.

1. Multilayer Ceramic Capacitor Hereinafter, a multilayer ceramic capacitor according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an external perspective view of a multilayer ceramic capacitor according to an embodiment of the present invention. FIG. 2 is a cross-sectional view (II-II cross-sectional view shown in FIG. 1) along the length direction of the multilayer ceramic capacitor according to one embodiment of the present invention. 3 is a cross-sectional view (III-III cross-sectional view shown in FIG. 2) along the width direction of the multilayer ceramic capacitor according to one embodiment of the present invention. FIG. 4 is a schematic view of the first internal electrode provided in the multilayer ceramic capacitor according to one embodiment of the present invention as viewed in the stacking direction. FIG. 5 is a schematic view of the second internal electrode provided in the multilayer ceramic capacitor according to the embodiment of the present invention as viewed in the stacking direction. FIG. 6 is a schematic view of a state in which the first internal electrode and the second internal electrode provided in the multilayer ceramic capacitor according to one embodiment of the present invention are stacked along the stacking direction.

  The multilayer ceramic capacitor 10 according to this embodiment includes a multilayer body 20 formed in a rectangular parallelepiped shape, and a first external electrode 90 a and a second external electrode 90 b formed on the surface of the multilayer body 20. The multilayer ceramic capacitor 10 has a length direction (hereinafter referred to as “L direction”) dimension L, a width direction (hereinafter referred to as “W direction”) dimension W, and a dimension in the stacking direction (hereinafter “T”). Direction)) is T dimension, L dimension is 1.5 mm or more and 3.4 mm or less, W dimension is 0.7 mm or more and 2.7 mm or less, and T dimension is 0.5 mm or more and 2.7 mm. The following is preferable.

(Laminated body 20)
The stacked body 20 is formed in a rectangular parallelepiped shape by stacking a plurality of dielectric layers 40, a plurality of first internal electrodes 50a, and a plurality of second internal electrodes 50b. The stacked body 20 includes a first main surface 22a and a second main surface 22b opposed in the T direction, a first side surface 24a and a second side surface 24b opposed in the W direction orthogonal to the T direction, and the T direction. And a first end face 26a and a second end face 26b that face each other in the L direction orthogonal to the W direction. The laminated body 20 is preferably rounded at its corners and ridges. Here, the corner portion is a portion where three surfaces of the surface of the laminate 20 intersect, and the ridge line portion is a portion where two surfaces of the surface of the laminate 20 intersect. In addition, unevenness or the like may be formed on part or all of the main surface, side surfaces, and end surfaces of the stacked body 20. The laminate 20 has a dimension in the L direction of 0.25 mm to 3.20 mm, a dimension in the W direction of 0.125 mm to 2.50 mm, and a dimension in the T direction of 0.125 mm to 2.50 mm. Although it is preferable that it is as follows, it is not particularly limited.

  The stacked body 20 includes a counter electrode portion 32 where the first internal electrode 50a and the second internal electrode 50b face each other, and a first side portion 34a located between the counter electrode portion 32 and the first side surface 24a. (W gap), the second side part 34b (same as above) located between the counter electrode part 32 and the second side surface 24b, and the counter electrode part 32 and the first end face 26a. The first end portion 36a (L gap) having a first lead portion 70a, which will be described later, is located between the counter electrode portion 32 and the second end face 26b, and has a second lead portion 70b, which will be described later. Second end 36b (same as above).

(Dielectric layer 40)
The dielectric layer 40 is sandwiched and laminated between the first internal electrode 50a and the second internal electrode 50b. The dielectric layer 40 can be formed using a dielectric material whose main component is a dielectric ceramic such as BaTiO ₃ , CaTiO ₃ , SrTiO _3, or CaZrO ₃ . Moreover, you may add subcomponents, such as a Mn compound, Fe compound, Cr compound, Co compound, Ni compound, to the main components as mentioned above. The subcomponent is less in content than the main component. The number of laminated dielectric layers 40 is not particularly limited, but is preferably 170 or more and 720 or less (including an outer layer portion described later). The thickness of the dielectric layer 40 per layer is preferably 0.4 μm or more and 20 μm or less.

  Dielectric layer 40 includes an outer layer portion located on each of first main surface 22a side and second main surface 22b side, and an inner layer portion located in a region sandwiched between these outer layer portions in the T direction. Specifically, the outer layer portion located on the first main surface 22a side includes an inner electrode (first inner electrode 50a or second inner electrode 50b) closest to the first main surface 22a and the first main surface 22a. The dielectric layer 40 located between the surface 22a and the outer layer portion located on the second main surface 22b side includes the inner electrode closest to the second main surface 22b and the second main surface 22b. It is a dielectric layer 40 located between the two. The inner layer portion is the dielectric layer 40 located between the internal electrode closest to the first main surface 22a and the internal electrode closest to the second main surface 22b. The thickness along the T direction of the outer layer portion on the first main surface 22a side and the outer layer portion on the second main surface 22b side is preferably 10 μm or more and 300 μm or less, respectively.

(First internal electrode 50a and second internal electrode 50b)
The first internal electrode 50 a extends in a flat plate shape on the surface of the dielectric layer 40, and its end is exposed to the first end surface 26 a of the multilayer body 20, so that the first internal electrode 50 a is electrically connected to the first external electrode 90 a. Connected to. The second internal electrode 50 b extends in a flat plate shape on the surface of the dielectric layer 40, and its end is exposed to the second end surface 26 b of the multilayer body 20, so that the second internal electrode 50 b is electrically connected to the second external electrode 90 b. Connected to.

  In this embodiment, a first opposing portion 60a, which will be described later, which is a part of the first internal electrode 50a, and a second opposing portion 60b, which will be described later, which is a part of the second internal electrode 50b, are dielectrics. Capacitance is generated by facing each other through the layer 40. As a result, the multilayer ceramic capacitor 10 according to this embodiment functions as a capacitor. The first internal electrode 50a and the second internal electrode 50b include, for example, metals such as Ni, Cu, Ag, Pd, and Au, and alloys containing at least one of these metals (for example, Ag—Pd alloy) ) Using an appropriate conductive material. Moreover, it is preferable that the thickness per one layer of the 1st internal electrode 50a and the 2nd internal electrode 50b is about 0.2 micrometer or more and 2.0 micrometers or less, respectively. Furthermore, the total number of stacked layers of the first internal electrode 50a and the second internal electrode 50b is preferably 150 or more and 700 or less. When viewed in the T direction, the ratio of the first internal electrode 50a and the second internal electrode 50b covering the surface of the dielectric layer 40 is preferably 50% or more and 95% or less.

(First internal electrode 50a)
The first internal electrode 50a is drawn out to the first end face 26a side from the first opposing portion 60a, the first opposing portion 60a facing the second internal electrode 50b via the dielectric layer 40, and And a first lead portion 70a having a smaller dimension in the W direction than the first facing portion 60a.

(First facing portion 60a)
As for the 1st opposing part 60a, the edge part 62a of the W direction extends linearly along the L direction seeing in the T direction. The first facing portion 60a has a first tip edge portion 64a positioned on the tip end side (ie, an edge portion positioned on the second end face 26b side) when the first lead portion 70a side is the base side. ) Extends linearly along the W direction as viewed in the T direction. Then, the first facing portion 60a approaches the first tip edge portion 64a (or the second end surface 26b) at the corner portion where the edge 62a in the W direction and the first tip edge portion 64a intersect. In order to reduce the dimension in the W direction, the first opposing inclined portion 66a that inclines linearly when viewed in the T direction is provided. In addition, it is preferable that the 1st opposing part 60a is axisymmetric about the centerline extended along the L direction in the center part of the W direction seeing in the T direction.

(First drawer portion 70a)
The first lead portion 70a has a first lead flat portion 74a that extends linearly along the L direction when viewed in the T direction at a portion on the first end face 26a side of the edge portion 72a in the W direction. In addition, the first lead-out portion 70a is formed in the T direction so that the dimension in the W direction increases as it approaches the first facing portion 60a in the portion on the first facing portion 60a side of the edge portion 72a in the W direction. The first drawer inclined portion 76a is linearly inclined as viewed in FIG. The 1st drawer | tilt inclination part 76a connects the edge part by the side of the 2nd end surface 26b of the 1st drawer | drawing-out flat part 74a, and the edge part by the side of the 1st end surface 26a of the 1st opposing part 60a mutually. In addition, it is preferable that the 1st drawer | drawing-out part 70a is axisymmetric about the centerline extended along the L direction in the center part of the W direction seeing in the T direction.

(Second internal electrode 50b)
The second internal electrode 50b is drawn out through the dielectric layer 40 to the second facing portion 60b facing the first internal electrode 50a, the second facing portion 60b to the second end face 26b side, and And a second lead portion 70b having a smaller dimension in the W direction than the second facing portion 60b.

(Second facing portion 60b)
As for the 2nd opposing part 60b, the edge part 62b of the W direction extends linearly along the L direction seeing in the T direction. Further, the second facing portion 60b has a second leading edge portion 64b positioned on the leading end side (that is, an edge portion positioned on the first end face 26a side) when the second lead portion 70b side is the root side. ) Extends linearly along the W direction as viewed in the T direction. Then, as the second facing portion 60b approaches the second tip edge portion 64b (or the first end surface 26a) at the corner portion where the edge portion 62b in the W direction and the second tip edge portion 64b cross each other. In order to reduce the dimension in the W direction, there is a second opposing inclined portion 66b that inclines linearly when viewed in the T direction. In addition, it is preferable that the 2nd opposing part 60b is axisymmetric about the centerline extended along the L direction in the center part of the W direction seeing in the T direction.

(Second drawer portion 70b)
The second lead portion 70b has a second lead flat portion 74b that extends linearly along the L direction when viewed in the T direction at a portion of the edge portion 72b in the W direction on the second end face 26b side. In addition, the second lead-out portion 70b is formed in the T direction so that the dimension in the W direction increases as it approaches the second facing portion 60b in the portion on the second facing portion 60b side of the edge portion 72b in the W direction. The second drawer inclined portion 76b is inclined linearly as viewed in FIG. The second drawer inclined part 76b connects the end part on the first end face 26a side of the second drawer flat part 74b and the end part on the second end face 26b side of the second facing part 60b to each other. In addition, it is preferable that the 2nd drawer | drawing-out part 70b is axisymmetric about the centerline extended along the L direction in the center part of the W direction seeing in the T direction.

(Relationship between first opposing inclined portion 66a and first drawer inclined portion 76a)
As shown in FIG. 4, when viewed in the T direction, a straight line x ₁ indicated by a one-dot chain line in FIG. 4 that passes through the end portion on the first end face 26 a side of the first drawer inclined portion 76 a and extends along the L direction. And the acute angle α ₁ formed by the first drawer inclined portion 76a passes through the end of the first opposing inclined portion 66a on the first tip edge portion 64a side (or the second end face 26b side) and in the L direction. It is smaller than the acute angle β ₁ formed by the straight line y ₁ indicated by the alternate long and short dash line in FIG.

Preferably, as shown in FIG. 6, when viewed in the T direction, the first opposing inclined portion 66 a is positioned on the inner side in the L direction than the second leading inclined portion 76 b that faces through the dielectric layer 40. (That is, located on the right side of the straight line z ₁ indicated by the one-dot chain line on the left side of FIG. 6).

Preferably, as shown in FIG. 6, when viewed in the T direction, the first opposing inclined portion 66a is positioned on the inner side in the W direction than the second drawer inclined portion 76b (that is, in FIG. 6). It is arranged on the left side so as to be located below the straight line z ₃ indicated by a two-dot chain line.

(Relationship between second opposing inclined portion 66b and second drawer inclined portion 76b)
As shown in FIG. 5, when viewed in the T direction, a straight line x ₂ indicated by a one-dot chain line in FIG. 5 that passes through the end portion on the second end face 26 b side of the second drawer inclined portion 76 b and extends along the L direction. And the acute angle α ₂ formed by the second drawer inclined portion 76b passes through the end of the second opposing inclined portion 66b on the second tip edge 64b side (or the first end surface 26a side) and in the L direction. Is smaller than the acute angle β ₂ formed by the straight line y ₂ indicated by the alternate long and short dash line in FIG.

Preferably, as shown in FIG. 6, when viewed in the T direction, the second opposing inclined portion 66 b is located on the inner side in the L direction with respect to the first leading inclined portion 76 a facing through the dielectric layer 40. (That is, located on the left side of the straight line z ₂ indicated by the one-dot chain line on the right side of FIG. 6).

Preferably, as shown in FIG. 6, when viewed in the T direction, the second opposing inclined portion 66b is positioned on the inner side in the W direction with respect to the first drawer inclined portion 76a (that is, in FIG. 6). It is arranged on the right side so as to be located below the straight line z ₄ indicated by a two-dot chain line.

(Preferred acute angle size)
Preferably, the acute angle alpha ₂ of acute alpha ₁ and the second lead-out inclined portion 76b of the first lead inclined portion 76a, respectively, it is less than 60 degrees 45 degrees.

Preferably, an acute angle beta ₂ acute beta ₁ and second opposing inclined portion 66b of the first opposing inclined portion 66a, respectively, is less than 70 degrees 55 degrees.

(Preferred dimensions in the W direction)
Preferably, the first drawer portion 70a (that is, the portion having the first drawer flat portion 74a as an edge) excluding the portion having the first drawer inclined portion 76a as an edge, and the second drawer inclined portion. The dimension in the W direction of the second lead portion 70b (that is, the portion having the second lead flat portion 74b as an edge portion) excluding the portion having the edge portion 76b is 60 μm or more and 200 μm or less, respectively.

  Preferably, the first opposing portion 60a excluding the portion having the first opposing inclined portion 66a as an edge, and the second opposing portion 60b excluding the portion having the second opposing inclined portion 66b as an edge. The dimension in the W direction is 1400 μm or more and 3500 μm or less, respectively.

(First external electrode 90a and second external electrode 90b)
The first external electrode 90a is formed so as to cover the first end face 26a, and its end is electrically connected to the first internal electrode 50a exposed at the first end face 26a. The first external electrode 90a is extended from a portion formed on the first end surface 26a, and each of the first main surface 22a, the second main surface 22b, the first side surface 24a, and the second side surface 24b. It is preferable to be formed so as to reach a part. The first external electrode 90a may be formed only on the first end face 26a. On the other hand, the second external electrode 90b is formed so as to cover the second end surface 26b of the multilayer body 20, and its end is electrically connected to the second internal electrode 50b exposed at the second end surface 26b. The The second external electrode 90b is extended from the portion formed on the second end surface 26b, and each of the first main surface 22a, the second main surface 22b, the first side surface 24a, and the second side surface 24b. It is preferable to be formed so as to reach a part. The second external electrode 90b may be formed only on the second end face 26b.

  Each of the first external electrode 90a and the second external electrode 90b includes a base electrode layer formed so as to cover the first end face 26a or the second end face 26b, and plating formed on the surface of the base electrode layer Including layers.

  The base electrode layer includes at least one selected from a baking layer, a resin layer, a thin film layer, and the like.

  The baking layer is formed on the surface of the first end face 26a or the second end face 26b. The baking layer includes glass and metal. The glass of the baking layer contains, for example, B, Si, Ba, Mg, Al and Li. Moreover, the metal of the baking layer contains at least one selected from Cu, Ni, Ag, Pd, Ag—Pd alloy, Au, and the like, for example. The baking layer is formed by applying and baking a conductive paste containing glass and metal on the laminate 20. The baking layer may be formed by simultaneous baking with the first internal electrode 50a and the second internal electrode 50b, or baking after baking the first internal electrode 50a and the second internal electrode 50b. May be formed. Note that the baking layer may have a multilayer structure. The thickness of the thickest portion of the baking layer is preferably 10 μm or more and 50 μm or less.

  The resin layer may be formed on the surface of the baking layer, or may be directly formed on the surface of the first end surface 26a or the second end surface 26b without forming the baking layer. The resin layer includes, for example, conductive particles and a thermosetting resin. The resin layer may have a multi-layer structure. The thickness of the thickest part of the resin layer is preferably 10 μm or more and 150 μm or less.

  The thin film layer is formed by a thin film forming method such as sputtering or vapor deposition. The thin film layer is a layer of 1 μm or less on which metal particles are deposited.

  The plating layer preferably contains at least one metal or alloy selected from, for example, Cu, Ni, Sn, Ag, Pd, an Ag—Pd alloy and Au. The plating layer may have a multi-layer structure. Preferably, it is a two-layer structure including Ni plating formed on the lower layer side and Sn plating formed on the upper layer side. By forming the Ni plating so as to cover the base electrode layer, erosion due to solder can be prevented. Further, since the Sn plating is further formed on the surface of the Ni plating, the wettability of the solder can be improved, so that the mounting operation can be easily performed. The thickness of each plating layer is preferably 1 μm or more and 15 μm or less.

  Each of the first external electrode 90a and the second external electrode 90b is directly formed on the surface of the laminate 20, and is a plating electrode that is electrically connected to the first internal electrode 50a or the second internal electrode 50b. The structure may include a layer. In such a case, the plating electrode layer may be formed after disposing the catalyst on the surface of the laminate 20 as a pretreatment. The plating electrode layer preferably includes a lower layer plating electrode formed on the surface of the laminate 20 and an upper layer plating electrode formed on the surface of the lower layer plating electrode.

  Each of the lower plating electrode and the upper plating electrode preferably includes at least one metal selected from, for example, Cu, Ni, Sn, Pb, Au, Ag, Pd, Bi, and Zn, or an alloy containing the metal. The lower plating electrode is preferably formed using Ni having solder barrier performance, and the upper plating electrode is preferably formed using Sn or Au having good solder wettability. In addition, for example, when the first internal electrode 50a and the second internal electrode 50b are formed using Ni, the lower plating electrode is preferably formed using Cu having good bonding properties with Ni.

  Note that the upper plating electrode may be formed as necessary, and each of the first external electrode 90a and the second external electrode 90b may be composed of only the lower plating electrode. The upper plating electrode may be the outermost layer, or another plating electrode may be formed on the surface of the upper plating electrode. The thickness per layer of the plating electrode layer is preferably 1 μm or more and 15 μm or less. It is preferable that a plating electrode layer does not contain glass. The metal ratio per unit volume of the plating electrode layer is preferably 99% by volume or more.

(effect)
In the multilayer ceramic capacitor 10 according to this embodiment, when the first internal electrode 50a is viewed in the T direction, the acute angle α ₁ formed by the straight line x ₁ indicated by the alternate long and short dash line in FIG. 4 and the first lead inclined portion 76a. However, it is smaller than the acute angle β ₁ formed by the straight line y ₁ indicated by the alternate long and short dash line in FIG. Note that the second internal electrode 50b has the same shape as the first internal electrode 50a. With such a shape, the area where the first internal electrode 50a and the second internal electrode 50b exist independently when viewed in the T direction can be reduced. That is, since the portion where the first internal electrode 50a and the second internal electrode 50b are fixed to the dielectric layer 40 can be increased, the internal stress generated in the stacked body 20 can be relaxed. As a result, the multilayer ceramic capacitor 10 according to this embodiment can provide a highly reliable multilayer ceramic capacitor 10 with improved structural defects such as peeling and cracks.

Further, when viewed in the T direction, the first opposing inclined portion 66a is positioned on the inner side in the L direction with respect to the second leading inclined portion 76b opposed via the dielectric layer 40 (that is, FIG. 6). Are arranged on the left side of the straight line ₁ so as to be located on the right side of the straight line z ₁ indicated by a one-dot chain line. Note that the second internal electrode 50b has the same shape as the first internal electrode 50a. Thereby, since the internal stress which generate | occur | produces in the laminated body 20 can be relieve | moderated further, it becomes possible to exhibit the effect of this invention more reliably.

  Further, when viewed in the T direction, the first opposing inclined portion 66a is disposed so as to be located on the inner side in the W direction than the second drawer inclined portion 76b. The second opposing inclined portion 66b is also disposed in the same manner. As a result, the effects of the present invention can be more reliably exhibited.

The acute angle alpha ₂ of acute alpha ₁ and the second lead-out inclined portion 76b of the first lead inclined portion 76a, respectively, is preferably 60 degrees or less than 45 degrees. As a result, the effects of the present invention can be more reliably exhibited.

Moreover, an acute angle beta ₂ acute beta ₁ and second opposing inclined portion 66b of the first opposing inclined portion 66a, respectively, is preferably 70 degrees or less than 55 degrees. As a result, the effects of the present invention can be more reliably exhibited.

  Furthermore, W of the 1st drawer | drawing-out part 70a except the part which uses the 1st drawer | drawing-in inclination part 76a as an edge, and the 2nd drawer part 70b except the part which uses the 2nd drawer | tilt inclination part 76b as an edge. The dimension in the direction is preferably 60 μm or more and 200 μm or less, respectively. As a result, the effects of the present invention can be more reliably exhibited.

  And W of the 1st opposing part 60a except the part which makes the edge part the 1st opposing inclination part 66a, and the 2nd opposing part 60b except the part which makes the 2nd opposing inclination part 66b an edge part. The dimension in the direction is preferably 1400 μm or more and 3500 μm or less, respectively. As a result, the effects of the present invention can be more reliably exhibited.

  Further, in the multilayer ceramic capacitor 10 according to this embodiment, the L dimension is 1.5 mm or more and 3.4 mm or less, the W dimension is 0.7 mm or more and 2.7 mm or less, and the T dimension is 0.5 mm or more. It is preferable that it is 2.7 mm or less. Thereby, when viewed in the T direction, the area of the first internal electrode 50a protruding from the second internal electrode 50b (and the area of the second internal electrode 50b protruding from the first internal electrode 50a) becomes a certain level or more. Peeling and cracking due to the increase in internal stress can be suppressed.

  Furthermore, the total number of stacked layers of the first internal electrode 50a and the second internal electrode 50b is preferably 150 or more and 700 or less. Thereby, when viewed in the T direction, the area of the first internal electrode 50a protruding from the second internal electrode 50b (and the area of the second internal electrode 50b protruding from the first internal electrode 50a) becomes a certain level or more. Peeling and cracking due to the increase in internal stress can be suppressed.

2. Manufacturing Method An example of a manufacturing method of a multilayer ceramic capacitor according to an embodiment of the present invention will be described by taking the above-described manufacturing method of the multilayer ceramic capacitor 10 as an example.

  First, a conductive paste for a dielectric sheet and internal electrodes is prepared. The dielectric sheet and the conductive paste for internal electrodes include a binder and a solvent. As the binder and the solvent, known organic binders and organic solvents can be used.

  Next, an internal electrode pattern is formed on the surface of the dielectric sheet using a conductive paste for internal electrodes. The internal electrode pattern is formed, for example, by printing a conductive paste for internal electrodes on the surface of the dielectric sheet so as to be the internal electrode pattern according to the present invention by screen printing or gravure printing.

  Furthermore, a predetermined number of dielectric sheets for outer layers on which no internal electrode pattern is formed are laminated, a predetermined number of dielectric sheets for inner layers on which the internal electrode patterns are formed are laminated, and the internal electrode pattern is formed on the surface. A laminated sheet is produced by laminating a predetermined number of dielectric sheets for outer layers in which no is formed.

  And a lamination block is produced by pressing a lamination sheet in the T direction. Examples of the pressing means include an isostatic press.

  Next, the laminated chip is cut out by cutting the laminated block into a predetermined dimension.

  Furthermore, a laminated body is produced by firing the laminated chip. The firing temperature is preferably 900 ° C. or higher and 1300 ° C. or lower, although it depends on the dielectric and internal electrode materials.

  Finally, external electrodes are formed on each end face of the laminate. An external electrode baking layer can be formed by applying and baking a conductive paste for an external electrode on each of both end faces of the laminate. The baking temperature is preferably 700 ° C. or higher and 900 ° C. or lower. If necessary, the surface of the baking layer may be plated. In addition, you may form a plating electrode layer directly on the surface of a laminated body, without forming a baking layer. In such a case, after plating the surface of the laminate, a base plating film is formed on a portion exposed from the laminate of the internal electrodes. In performing the plating treatment, either electrolytic plating or electroless plating may be employed. The electroless plating has a demerit that a pretreatment with a catalyst or the like is required to improve the plating deposition rate, and the process becomes complicated. Therefore, it is usually preferable to employ electrolytic plating. As the plating method, barrel plating is preferably used. A surface conductor can also be formed. The surface conductor may be formed by printing a surface conductor pattern in advance on the surface of the outermost dielectric sheet and firing it simultaneously with the laminate, or the surface conductor pattern on the main surface of the laminate after firing. May be formed by printing and baking. If necessary, a plating layer may be formed on the surface of the plating electrode layer.

  As described above, the multilayer ceramic capacitor 10 according to one embodiment of the present invention can be manufactured.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation is carried out within the range of the summary.

DESCRIPTION OF SYMBOLS 10 Multilayer ceramic capacitor 20 Laminated body 22a 1st main surface 22b 2nd main surface 24a 1st side surface 24b 2nd side surface 26a 1st end surface 26b 2nd end surface 34a 1st side part (W gap)
34b Second side (same as above)
36a First end (L gap)
36b Second end (same as above)
40 Dielectric layer 50a 1st internal electrode 50b 2nd internal electrode 60a 1st opposing part 60b 2nd opposing part 62a Edge of W direction of 1st opposing part 62b W direction of 2nd opposing part Edge portion 64a First tip edge portion 64b Second tip edge portion 66a First counter inclined portion 66b Second counter inclined portion 70a First drawer portion 70b Second drawer portion 72a First drawer portion W Direction edge portion 72b W-direction edge portion of second extraction portion 74a first extraction flat portion 74b second extraction flat portion 76a first extraction inclined portion 76b second extraction inclined portion 90a first external electrode 90b Second external electrode

Claims (9)

A plurality of dielectric layers, a plurality of first internal electrodes, and a plurality of second internal electrodes are stacked to form a rectangular parallelepiped shape. A main surface, a first side surface and a second side surface facing each other in a width direction orthogonal to the stacking direction, a first end surface and a second side facing each other in a length direction orthogonal to the stacking direction and the width direction. A laminate including an end surface;
By being formed on the first end surface, the first external electrode electrically connected to the plurality of first internal electrodes, and by being formed on the second end surface, the plurality of first A multilayer ceramic capacitor comprising: a second external electrode electrically connected to the two internal electrodes;
The first internal electrode is led out to the first end face side from the first opposing portion, the first opposing portion facing the second internal electrode through the dielectric layer, and A first drawer portion having a width dimension smaller than that of the first facing portion,
The first facing portion has a widthwise dimension that decreases as it approaches the second end surface at a corner where the edge located on the second end surface side and the edge in the width direction intersect. Having a first opposing inclined portion that is inclined linearly when viewed in the stacking direction,
The first drawer portion is seen in the stacking direction so that the width direction dimension becomes larger as it approaches the first opposing portion in the portion on the first opposing portion side of the edge portion in the width direction. A first drawer inclined portion that is inclined linearly;
The second internal electrode is led out to the second end face side from the second opposing portion, the second opposing portion facing the first internal electrode through the dielectric layer, and A second drawer portion having a width dimension smaller than that of the second facing portion,
The second facing portion has a width-direction dimension that decreases as it approaches the first end surface at a corner portion where the edge portion located on the first end surface side and the edge portion in the width direction intersect. Having a second opposing inclined portion inclined linearly when viewed in the stacking direction,
The second drawer portion is seen in the stacking direction so that the width direction dimension becomes larger as it approaches the second facing portion at the portion on the second facing portion side of the edge in the width direction. A second drawer inclined portion that is inclined linearly;
When viewed in the stacking direction, an acute angle formed between a straight line that passes through the first end face side end portion of the first drawer inclined portion and extends along the length direction, and the first drawer inclined portion is: It is smaller than an acute angle formed between a straight line that passes through the end portion on the second end face side of the first opposing inclined portion and extends in the length direction, and the first opposing inclined portion, and the second opposing inclined portion An acute angle formed between a straight line that passes through the end portion on the second end face side of the drawer inclined portion and extends in the length direction and the second drawer inclined portion is the first angle of the second opposing inclined portion. A multilayer ceramic capacitor characterized in that the multilayer ceramic capacitor is smaller than an acute angle formed by a straight line passing through an end portion on the end face side and extending along the length direction and the second opposing inclined portion.   When viewed in the stacking direction, the first opposing inclined portion is disposed so as to be located on the inner side in the length direction than the second drawer inclined portion facing through the dielectric layer, and 2. The multilayer ceramic capacitor according to claim 1, wherein the second opposing inclined portion is disposed so as to be located on an inner side in a length direction than the first drawer inclined portion facing through the dielectric layer. .   When viewed in the stacking direction, the first opposing inclined portion is disposed so as to be positioned on the inner side in the width direction than the second drawer inclined portion, and the second opposing inclined portion is the first opposing inclined portion. 3. The multilayer ceramic capacitor according to claim 1, wherein the multilayer ceramic capacitor is disposed so as to be located on an inner side in a width direction than one drawer inclined portion.   When viewed in the stacking direction, an acute angle formed between a straight line that passes through the first end face side end portion of the first drawer inclined portion and extends along the length direction, and the first drawer inclined portion, and The acute angle formed between the straight line extending through the end of the second drawer inclined portion on the second end face side and extending along the length direction and the second drawer inclined portion is 45 degrees or more and 60 degrees, respectively. The multilayer ceramic capacitor according to claim 1, which is the following.   When viewed in the stacking direction, an acute angle formed by a straight line passing through the end of the first opposing inclined portion on the second end face side and extending along the length direction, and the first opposing inclined portion, and The acute angle formed between the straight line that passes through the first end face side end portion of the second opposing inclined portion and extends in the length direction and the second opposing inclined portion is 55 degrees or more and 70 degrees, respectively. The multilayer ceramic capacitor according to claim 1, which is as follows.   A width direction of the first drawer portion excluding a portion having the first drawer inclined portion as an edge portion and a width of the second drawer portion excluding a portion having the second drawer inclined portion as an edge portion. 6. The multilayer ceramic capacitor according to claim 1, wherein the dimensions are 60 μm or more and 200 μm or less, respectively.   A width direction of the first opposing portion excluding a portion having the first opposing inclined portion as an edge and a second opposing portion excluding a portion having the second opposing inclined portion as an edge 7. The multilayer ceramic capacitor according to claim 1, wherein each of the dimensions is 1400 μm or more and 3500 μm or less.   The dimension in the length direction is 1.5 mm or more and 3.4 mm or less, the dimension in the width direction is 0.7 mm or more and 2.7 mm or less, and the dimension in the stacking direction is 0.5 mm or more and 2.7 mm or less. The multilayer ceramic capacitor according to claim 1.   The multilayer ceramic capacitor according to claim 1, wherein a total number of the first internal electrode and the second internal electrode is 150 or more and 700 or less.

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