Multilayer ceramic capacitor

Abstract

Provided is a laminated ceramic capacitor having high moisture resistance reliability by forming a dense dielectric in an outer layer portion constituting a laminated body. In the multilayer ceramic capacitor, the dielectric in the region DW of the outer layer on the side surface side contains 0.995-1.003 relative to Ba / (Ti + Zr), and the content of Mg per 100 mol parts of Ti is 0.5-5.0 mol parts more than that of the dielectric in the central part of the effective part 11, or the content of Mg per 100 mol parts of Ti is 0.5-5.0 mol parts more than that of Mg per 100 mol parts of Ti in the dielectric in the region DW of the outer layer on the side surface side. The content of Mn per 100 mol parts of Ti is 0.4-2.0 mol parts more than that of the dielectric in the central part of the effective part (11), the content of Ba / (Ti + Zr) in the dielectric in the region DL of the outer layer on the end surface side is 0.995-1.003, the content of Mg per 100 mol parts of Ti is 0.25-2.5 mol parts more than that of the dielectric in the central part of the effective part (11), or the content of Mn per 100 mol parts of Ti in the dielectric in the region DL of the outer layer on the end surface side is 0.995-1.003, and the content of Mg per 100 mol parts of Ti in the dielectric in the region DL of the outer layer on the end surface side is 0.995-1.003. The content of Mn relative to 100 parts by mole of Ti is more than 0.2 parts by mole and less than 1.0 parts by mole more than the dielectric in the central part of the effective part (11).

Description

Technical Field

[0001] The present invention relates to a laminated ceramic capacitor. Background Art

[0002] Typically, a multilayer ceramic capacitor comprises a stack including a plurality of stacked dielectric layers and a plurality of internal electrode layers, and an external electrode disposed at a given position of the stack to be electrically connected to the internal electrode layer. As main regions constituting the stack, there are an effective portion in which the internal electrode layers overlap with each other and form a capacitor, an outer layer portion sandwiching the effective portion from the stacking direction (hereinafter referred to as a “main surface side outer layer portion”), an outer layer portion sandwiching the effective portion from a width direction intersecting the stacking direction (hereinafter referred to as a “side surface side outer layer portion”), an outer layer portion sandwiching the effective portion from a length direction intersecting the stacking direction and the width direction (hereinafter referred to as a “end surface side outer layer portion”), and an outer layer portion disposed at the four corners of the stack in a plan view so as to connect the side surface side outer layer portion and the end surface side outer layer portion (hereinafter referred to as a “corner side outer layer portion”).

[0003] The laminate is formed through a firing process. However, if the conditions of the firing process are adapted to the effective part, the above-mentioned outer layer parts tend to generate grain growth of dielectric particles and spaces between particles inside the outer layer parts. Such grain growth (increase in the diameter of sintered particles) tends to cause a deviation in insulation resistance. On the other hand, the spaces between particles become a path for water infiltrating from the outside. In particular, the spaces generated in the side outer layer parts and the end outer layer parts form a path for water to reach the effective part, thereby reducing the moisture resistance reliability of the laminated ceramic capacitor.

[0004] Therefore, there is a demand for the development of a multilayer ceramic capacitor that has improved moisture resistance reliability by preventing moisture intrusion from the outside by forming a dense dielectric in a predetermined region such as a side outer layer portion.

[0005] Prior Art Literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2009-32833 Summary of the invention

[0008] Problem that the invention aims to solve

[0009] An object of the present invention is to provide a laminated ceramic capacitor having high moisture resistance reliability by preventing water from entering from the outside by forming a dense dielectric in a predetermined region such as a side outer layer portion constituting a laminated body.

[0010] Technical solutions to solve problems

[0011] The inventors of the present invention discovered that by forming a dielectric layer of a stacked ceramic capacitor containing Ba, Ti and Zr, and containing Mg or Mn, and adjusting the content ratio of Ba, Ti and Zr and the content of Mg or Mn in a given area such as the side outer layer, a dense dielectric can be formed and the moisture resistance reliability of the stacked ceramic capacitor is improved, thereby ultimately completing the present invention.

[0012] That is, the present invention is a laminated ceramic capacitor comprising a laminated body including a plurality of laminated dielectric layers and a plurality of internal electrode layers, and external electrodes arranged to be electrically connected to the internal electrode layers, wherein:

[0013] The dielectric layer contains Ba, Ti and Zr, and contains Mg or Mn,

[0014] The stacked body comprises a first main surface and a second main surface which are opposite to each other in a stacking direction of the dielectric layer and the internal electrode layer, a first side surface and a second side surface which are opposite to each other in a width direction which intersects both the stacking direction and a length direction in which the internal electrode layer extends toward the external electrode, and a first end surface and a second end surface which are opposite to each other in a length direction which intersects the stacking direction and the width direction.

[0015] The external electrodes are respectively arranged on the first end surface and the second end surface,

[0016] In the stacked body, when the area where the internal electrode layers overlap each other when viewed from the stacking direction is set as the effective part, the area opposite to the effective part sandwiched in the stacking direction is set as the first main surface side outer layer part and the second main surface side outer layer part, the area opposite to the effective part sandwiched in the width direction is set as the first side surface side outer layer part and the second side surface side outer layer part, and the area opposite to the effective part sandwiched in the length direction is set as the first end surface side outer layer part and the second end surface side outer layer part,

[0017] In the central portion in the longitudinal direction of the first side surface outer layer portion or the second side surface outer layer portion, in the dielectric in the region between the first side surface or the second side surface and the internal electrode layer,

[0018] The content ratio of Ba, Ti and Zr, Ba / (Ti+Zr), is 0.995 or more and 1.003 or less.

[0019] The content of Mg relative to 100 molar parts of Ti is 0.5 molar parts or more and 5.0 molar parts or less than the content of Mg relative to 100 molar parts of Ti in the dielectric of the region in the central part of the width direction and the longitudinal direction of the stack, or the content of Mn relative to 100 molar parts of Ti is 0.4 molar parts or more and 2.0 molar parts or less than the content of Mn relative to 100 molar parts of Ti in the dielectric of the effective part in the central part of the width direction and the longitudinal direction,

[0020] In the first end surface side outer layer portion or the second end surface side outer layer portion, in the dielectric in the region between the first end surface or the second end surface and the internal electrode layer,

[0021] The content ratio of Ba, Ti and Zr, Ba / (Ti+Zr), is 0.995 or more and 1.003 or less.

[0022] The content of Mg relative to 100 mole parts of Ti is 0.25 mole parts or more and 2.5 mole parts or less than the content of Mg relative to 100 mole parts of Ti in the dielectric in the effective part in the central part of the width direction and the longitudinal direction, or the content of Mn relative to 100 mole parts of Ti is 0.2 mole parts or more and 1.0 mole parts or less than the content of Mn relative to 100 mole parts of Ti in the dielectric in the region of the stack located in the central part of the width direction and the longitudinal direction.

[0023] Effects of the Invention

[0024] According to the present invention, a laminated ceramic capacitor can be provided which has a high moisture resistance reliability and can prevent water intrusion from the outside by forming a dense dielectric in a predetermined region such as a side outer layer portion constituting a laminated body. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a perspective view of the appearance of a multilayer ceramic capacitor according to the present invention.

[0026] Figure 2 It is along Figure 1 A cross-sectional view of a multilayer ceramic capacitor taken along line II is shown.

[0027] Figure 3 It is along Figure 2 FIG. 1 is a cross-sectional view of a multilayer ceramic capacitor taken along line II-II.

[0028] Figure 4 It is along Figure 2 FIG. 1 is a cross-sectional view of a multilayer ceramic capacitor taken along line III-III.

[0029] Figure 5It is along Figure 1 FIG. 1 is a cross-sectional view of a multilayer ceramic capacitor taken along line IV-IV.

[0030] Figure 6 It is along Figure 2 FIG. 1 is a cross-sectional view of a multilayer ceramic capacitor taken along line VV shown in FIG.

[0031] Figure 7 Yes Figure 5 The enlarged partial view shows the vicinity of the end in the width direction W of the internal electrode layer. DETAILED DESCRIPTION

[0032] Hereinafter, embodiments of the present invention will be described. Figure 1 It is a schematic perspective view of a multilayer ceramic capacitor 1 according to the embodiment. Figure 2 It is along Figure 1 FIG. 1 is a cross-sectional view of the multilayer ceramic capacitor 1 taken along line II shown in FIG. Figure 3 It is along Figure 2 FIG. 1 is a cross-sectional view of the multilayer ceramic capacitor 1 taken along line II-II. Figure 4 It is along Figure 2 FIG. 1 is a cross-sectional view of the multilayer ceramic capacitor 1 taken along line III-III. Figure 5 It is along Figure 1 FIG. 1 is a cross-sectional view of the multilayer ceramic capacitor 1 taken along line IV-IV. Figure 6 It is along Figure 2 FIG. 1 is a cross-sectional view of the multilayer ceramic capacitor 1 taken along line VV. Figure 7 Yes Figure 5 The enlarged partial view of the end of the internal electrode layer in the width direction W is shown. The II line passes through the center of the multilayer ceramic capacitor 1 in the width direction W described later, and the IV-IV line passes through the center in the length direction L described later.

[0033] In the following description, as a term indicating the orientation of the multilayer ceramic capacitor 1, the direction in which the pair of external electrodes 40 are provided is referred to as the length direction L. The direction in which the dielectric layer 20 and the internal electrode layer 30 are stacked is referred to as the stacking direction T. The direction intersecting either the length direction L or the stacking direction T is referred to as the width direction W. In the embodiment, the length direction L, the stacking direction T, and the width direction W are orthogonal to each other. In addition, Figure 2 The section shown is also referred to as the LT section. Figure 3 , Figure 4 The section shown is also referred to as the LW section. Figure 5 , Figure 6 The section shown is also referred to as the WT section.

[0034] (Multilayer Ceramic Capacitors)

[0035] The multilayer ceramic capacitor 1 includes a laminate 10 including a plurality of laminated dielectric layers 20 and a plurality of internal electrode layers 30 , and a pair of external electrodes 40 provided at both ends of the laminate 10 .

[0036] (Laminated body)

[0037] The laminate 10 has a substantially rectangular parallelepiped shape. Preferably, the corners and ridges of the laminate 10 are rounded. The corner is a portion where three faces of the laminate intersect, and the ridge is a portion where two faces of the laminate intersect. In addition, the dimension of the length direction L of the laminate 10 is not necessarily longer than the dimension of the width direction W. In addition, a part or all of the surface constituting the laminate 10 may be formed with concavities and convexities.

[0038] The size of the laminate 10 is not particularly limited, but if the dimension in the longitudinal direction L of the laminate 10 is set as the L dimension, the L dimension is preferably 0.2 mm or more and 10 mm or less. In addition, if the dimension in the stacking direction T of the laminate 10 is set as the T dimension, the T dimension is preferably 0.1 mm or more and 10 mm or less. In addition, if the dimension in the width direction W of the laminate 10 is set as the W dimension, the W dimension is preferably 0.1 mm or more and 10 mm or less.

[0039] like Figure 1 as well as Figure 2 As shown, the stack 10 has a first main surface TS1 and a second main surface TS2 opposite to each other in the stacking direction T, a first side surface WS1 and a second side surface WS2 opposite to each other in the width direction W intersecting the stacking direction T, and a first end surface LS1 and a second end surface LS2 opposite to each other in the length direction L intersecting the stacking direction T and the width direction W.

[0040] (Dielectric layer)

[0041] The plurality of dielectric layers 20 stacked in the stacked body 10 include a plurality of ceramic particles containing Ba and Ti. The ceramic particles are, for example, of the general formula A m Crystal particles of a perovskite type compound represented by BO3 (A is Ba, B is Ti, and may contain Zr in addition to Ti, O is oxygen, and m is the molar ratio of A to B).

[0042] The dielectric layer 20 contains Zr as a minor component in the perovskite compound as a main component. There is no particular limitation on the existence form of Zr in the dielectric layer 20. For example, it can be set to a structure in which the core and the shell cannot be clearly distinguished inside the crystal particles of the perovskite compound, or it can also be a structure in which the core of the perovskite compound containing Ba and Ti and the shell formed by Zr solid solution around the core constitute the ceramic particles.

[0043] In addition, the dielectric layer 20 contains Mg or Mn as a minor component in the perovskite compound as the main component. There is no particular limitation on the existence form of Mg or Mn in the dielectric layer 20. For example, it can also be a structure in which the core and shell cannot be clearly distinguished by solid solution in the crystalline particles of the perovskite compound, or it can also be a structure in which the core of the perovskite compound containing Ba and Ti and the shell formed by solid solution of Mg or Mn around the core constitute the ceramic particles. In addition, RE (Y, La, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb), Si, Ni, V, Al, etc. can also be contained as minor components together with Mg or Mn.

[0044] The thickness of the dielectric layer 20 is preferably not less than 0.5 μm and not more than 72 μm. The number of laminated dielectric layers 20 is preferably not less than 10 and not more than 700. In addition, the number of dielectric layers 20 is the sum of the number of dielectric layers of the effective portion 11 and the number of dielectric layers of the first main surface side outer layer portion TG1 and the second main surface side outer layer portion TG2.

[0045] (Internal electrode layer)

[0046] The plurality of internal electrode layers 30 stacked in the stacked body 10 are composed of first internal electrode layers 31 and second internal electrode layers 32. The plurality of first internal electrode layers 31 are arranged on the plurality of dielectric layers 20. The plurality of second internal electrode layers 32 are arranged on the plurality of dielectric layers 20. The plurality of first internal electrode layers 31 and the plurality of second internal electrode layers 32 are alternately arranged in the stacking direction T of the stacked body 10.

[0047] The first internal electrode layer 31 includes a first opposing portion 31A opposing the second internal electrode layer 32 and a first lead portion 31B led out from the first opposing portion 31A toward the first end surface LS1. The first lead portion 31B is exposed at the first end surface LS1.

[0048] The second internal electrode layer 32 includes a second opposing portion 32A opposed to the first internal electrode layer 31 and a second lead portion 32B led out from the second opposing portion 32A toward the second end surface LS2. The second lead portion 32B is exposed at the second end surface LS2.

[0049] The first internal electrode layer 31 and the second internal electrode layer 32 are made of a suitable conductive material such as a metal such as Ni, Cu, Ag, Pd, Au, or an alloy containing at least one of these metals. When an alloy is used, the first internal electrode layer 31 and the second internal electrode layer 32 may be made of, for example, an Ag-Pd alloy.

[0050] The thickness of each of the first internal electrode layer 31 and the second internal electrode layer 32 is preferably about 0.2 μm or more and 3.0 μm or less, for example. The total number of the first internal electrode layers 31 and the second internal electrode layers 32 is preferably 5 or more and 350 or less.

[0051] (External Electrode)

[0052] The external electrode 40 is composed of a first external electrode 40A and a second external electrode 40B.

[0053] The first external electrode 40A is arranged on the first end surface LS1 side. The first external electrode 40A is connected to the first internal electrode layer 31. The first external electrode 40A is arranged on the first end surface LS1, but it can also be arranged on at least any one of the first main surface TS1, the second main surface TS2, the first side surface WS1, and the second side surface WS2 in addition to the first end surface LS1. In the present embodiment, the first external electrode 40A is arranged on a part of the first main surface TS1, a part of the second main surface TS2, a part of the first side surface WS1, and a part of the second side surface WS2 in addition to being arranged on the first end surface LS1. In addition, the first external electrode 40A can also be arranged from the first end surface LS1 to either the first main surface TS1 or the second main surface TS2. That is, the cross-sectional shape of the first external electrode 40A can also be L-shaped (not shown).

[0054] The second external electrode 40B is arranged on the second end surface LS2 side. The second external electrode 40B is connected to the second internal electrode layer 32. The second external electrode 40B is arranged on the second end surface LS2, but it can also be arranged on at least any one of the first main surface TS1, the second main surface TS2, the first side surface WS1, and the second side surface WS2 in addition to being arranged on the second end surface LS2. In the present embodiment, the second external electrode 40B is arranged on a part of the first main surface TS1, a part of the second main surface TS2, a part of the first side surface WS1, and a part of the second side surface WS2 in addition to being arranged on the second end surface LS2. In addition, the second external electrode 40B can also be arranged from the second end surface LS2 to either the first main surface TS1 or the second main surface TS2. That is, the cross-sectional shape of the second external electrode 40B can also be L-shaped (not shown).

[0055] In the laminate 10, the first opposing portion 31A of the first internal electrode layer 31 and the second opposing portion 32A of the second internal electrode layer 32 are opposed to each other via the dielectric layer 20, thereby forming a capacitor. Therefore, a capacitor function is exerted between the first external electrode 40A connected to the first internal electrode layer 31 and the second external electrode 40B connected to the second internal electrode layer 32.

[0056] The first external electrode 40A and the second external electrode 40B can be formed, for example, by a base electrode layer and a plating layer disposed on the base electrode layer. A conductive paste containing a metal component and a glass component is applied to the first end face LS1 and the second end face LS2 of the stacked body 10, and then sintered to form the base electrode layer. As the metal component mixed in the conductive paste, for example, metals such as Cu, Ni, Ag, Pd, and Au, or alloys of Ag and Pd can be used.

[0057] The plating layer disposed on the base electrode layer includes, for example, at least one of metals such as Cu, Ni, Ag, Pd, and Au, or alloys such as Ag and Pd. The plating layer can be, for example, a two-layer structure of a Ni plating layer and a Sn plating layer. However, the plating layer can also be a single layer or multiple layers.

[0058] The stack 10 has an effective portion 11 in which internal electrode layers overlap with each other to form a capacitor, an outer layer portion TG on the main surface side of the effective portion 11 clamped from the stacking direction T, an outer layer portion WG on the side surface side of the effective portion 11 clamped from the width direction W intersecting the stacking direction T, and an outer layer portion LG on the end surface side of the effective portion 11 clamped from the length direction L intersecting the stacking direction T and the width direction W, as regions constituting the stack 10.

[0059] (Effective part)

[0060] The effective portion 11 is a portion that substantially functions as a capacitor in the laminate 10 and generates capacitance due to the first opposing portion 31A of the first internal electrode layer 31 and the second opposing portion 32A of the second internal electrode layer 32 facing each other via the dielectric layer 20 .

[0061] like Figure 2 As shown in FIG. 1 , the laminated body 10 includes an effective portion 11 , and a first main surface side outer layer portion TG1 and a second main surface side outer layer portion TG2 arranged in the lamination direction T so as to sandwich the effective portion 11 .

[0062] (Main surface side outer layer)

[0063] The first main surface side outer layer portion TG1 is located on the first main surface TS1 side of the stacked body 10. The first main surface side outer layer portion TG1 can be formed by laminating a plurality of dielectric layers 20 as ceramic layers located between the first main surface TS1 and the internal electrode layer 30 closest to the first main surface TS1. The dielectric layer 20 used in the first main surface side outer layer portion TG1 may be the same as the dielectric layer 20 used in the effective portion 11.

[0064] The second main surface side outer layer portion TG2 is located on the second main surface TS2 side of the stacked body 10. The second main surface side outer layer portion TG2 can be formed by stacking a plurality of dielectric layers 20 as ceramic layers located between the second main surface TS2 and the internal electrode layer 30 closest to the second main surface TS2. The dielectric layer 20 used in the second main surface side outer layer portion TG2 may be the same as the dielectric layer 20 used in the effective portion 11.

[0065] (Side outer layer)

[0066] The side outer layer portion WG is composed of a first side outer layer portion WG1 and a second side outer layer portion WG2. The first side outer layer portion WG1 is a portion including the dielectric layer 20 located between the effective portion 11 and the first side WS1. The second side outer layer portion WG2 is a portion including the dielectric layer 20 located between the effective portion 11 and the second side WS2. Figure 5 , the range of the first side outer layer portion WG1 and the second side outer layer portion WG2 in the WT cross section of the multilayer ceramic capacitor is shown. The side outer layer portion WG is also called a W gap or a side gap.

[0067] (Outer layer on the end surface)

[0068] The end surface side outer layer portion LG is composed of a first end surface side outer layer portion LG1 and a second end surface side outer layer portion LG2. The first end surface side outer layer portion LG1 is a portion including the dielectric layer 20 located between the effective portion 11 and the first end surface LS1. The second end surface side outer layer portion LG2 is a portion including the dielectric layer 20 located between the effective portion 11 and the second end surface LS2. Figure 2 , the range of the first end surface side outer layer portion LG1 and the second end surface side outer layer portion LG2 in the LT cross section of the multilayer ceramic capacitor is shown. The end surface side outer layer portion LG is also called an L gap or an end gap.

[0069] (area)

[0070] In the first side outer layer portion WG1 or the second side outer layer portion WG2, Figure 5 As shown in FIG. 1 , there is a region DW between the first side surface WS1 or the second side surface WS2 and the internal electrode layer 30. When moisture in the atmosphere penetrates into the interior of the stack 10 from the first side surface WS1 or the second side surface WS2, the region DW easily becomes a path for moisture to reach the internal electrode layer 30. In addition, in the first end surface side outer layer portion LG1 or the second end surface side outer layer portion LG2, Figure 2As shown in the figure, there is a region DL between the first end face LS1 or the second end face LS2 and the internal electrode layer 30. When moisture in the atmosphere penetrates into the interior of the stacked body 10 from the first end face LS1 or the second end face LS2 of the stacked body 10, the region DL easily becomes a path for moisture to reach the internal electrode layer 30. Therefore, by improving the density of the dielectric in the region DW and the region DL and reducing the gap between particles, it is possible to suppress the penetration of moisture into the internal electrode layer 30, thereby improving the moisture resistance reliability of the stacked ceramic capacitor.

[0071] (Moisture resistance reliability)

[0072] Multilayer ceramic capacitors having different content ratios of Ba, Ti, and Zr (Ba / Ti+Zr) and Mg or Mn in the dielectric in the side outer layer region DW and the end outer layer region DL were prepared as samples and a moisture resistance reliability evaluation test was performed.

[0073] The content ratio (Ba / Ti+Zr) and the increase in Mg or Mn are measured by performing elemental analysis based on transmission electron microscopy-energy dispersive X-ray spectroscopy (TEM-EDX) on the dielectric in the region DW and the region DL. The increase in Mg or Mn is the increase in the dielectric in the central portion of the effective portion 11 in the width direction W and the length direction L, and is a numerical value converted by converting the Ti content to 100 parts by mole. In addition, the content ratio (Ba / Ti+Zr) and the Mg or Mn content in the region DW of the side outer layer portion are measured in the central portion of the length direction L of the first side outer layer portion WG1 or the second side outer layer portion WG2.

[0074] (Test method)

[0075] A moisture load test was conducted on 36 samples at 125°C, 95% relative humidity, 0.1 MPa gauge pressure, and 4 V applied voltage. Samples whose logarithm of insulation resistance LogIR dropped by two digits from the start of the test were judged as failures. A Weibull plot was drawn, and MTTF (mean time to failure) of less than 72 hours was judged as unqualified (×), and 72 hours or more was judged as qualified (○).

[0076] (Test method for densification)

[0077] The end / side surface of the polished surface of the LT section and the LW section was observed by SEM, and the total area of ​​the voids relative to the total area of ​​the dielectric was measured within a range of 10 μm×10 μm from the end of the end / side surface, and the void ratio was calculated. When the void ratio was 3% or less, it was judged as qualified (0), and in other cases it was judged as unqualified (×).

[0078] (Test method for particle growth / sintered particle size)

[0079] Five samples were fractured to expose the end / side portions of the LT section and the LW section. In order to make the boundary (grain boundary) between the grains in the dielectric layer clear, the above samples were heat treated. The heat treatment temperature was set to a temperature at which grain growth (grain growth) did not occur and the grain boundary became clear, and in this experimental example, the treatment was performed at 1000°C.

[0080] The particles of the exposed dielectric layer were observed with a scanning electron microscope (SEM) at 20,000 times magnification. The field size was set to an area of ​​6.3 μm × 4.4 μm. A total of 300 particles of each sample were randomly selected from the obtained SEM image, and the area of ​​the inner part of the grain boundary of each particle was calculated by image analysis and the equivalent circle diameter was calculated, which was set as the sintered particle diameter.

[0081] The case where the sintered particle diameter D99 ≤ 0.5 μm was judged as acceptable (◯), and the cases other than that were judged as unacceptable (×).

[0082] [Table 1]

[0083]

[0084] [Table 2]

[0085]

[0086] As shown in Table 1, in the case where Mg was contained, good results of moisture resistance reliability were obtained in Examples 1 to 9.

[0087] That is, in the central portion of the first side outer layer portion WG1 or the second side outer layer portion WG2 in the longitudinal direction L, in the dielectric in the region DW between the first side surface WS1 or the second side surface WS2 and the internal electrode layer 30, the content ratio of Ba, Ti, and Zr Ba / (Ti+Zr) is greater than or equal to 0.995 and less than or equal to 1.003,

[0088] The content of Mg relative to 100 parts by mole of Ti is greater than the content of Mg relative to 100 parts by mole of Ti in the dielectric region of the effective portion 11 in the central portion in the width direction W and the length direction L by 0.5 parts by mole or more and 5.0 parts by mole or less,

[0089] In the first end surface side outer layer portion LG1 or the second end surface side outer layer portion LG2, in the dielectric in the region DL between the first end surface LS1 or the second end surface LS2 and the internal electrode layer 30,

[0090] The content ratio of Ba, Ti and Zr, Ba / (Ti+Zr), is 0.995 or more and 1.003 or less.

[0091] The content of Mg per 100 mol parts of Ti is 0.25 mol parts or more and 2.5 mol parts or less than the content of Mg per 100 mol parts of Ti in the central region of the effective portion 11 in the width direction W and the length direction L, thereby obtaining good results in the evaluation of moisture resistance reliability.

[0092] As shown in Table 2, in the case where Mn was contained, good results of moisture resistance reliability were obtained in Examples 10 to 18.

[0093] That is, in the central portion of the first side outer layer portion WG1 or the second side outer layer portion WG2 in the longitudinal direction L, in the dielectric in the region DW between the first side surface WS1 or the second side surface WS2 and the internal electrode layer 30, the content ratio of Ba, Ti, and Zr Ba / (Ti+Zr) is greater than or equal to 0.995 and less than or equal to 1.003,

[0094] The content of Mn relative to 100 mol parts of Ti is 0.4 mol parts or more and 2.0 mol parts or less than the content of Mn relative to 100 mol parts of Ti in the dielectric region of the central portion of the effective portion 11 in the width direction W and the length direction L,

[0095] In the first end surface side outer layer portion LG1 or the second end surface side outer layer portion LG2, in the dielectric in the region DL between the first end surface LS1 or the second end surface LS2 and the internal electrode layer 30,

[0096] The content ratio of Ba, Ti and Zr, Ba / (Ti+Zr), is 0.995 or more and 1.003 or less.

[0097] The content of Mn relative to 100 mol parts of Ti is 0.2 mol parts or more and 1.0 mol parts or less than the content of Mn relative to 100 mol parts of Ti in the central region of the effective portion 11 in the width direction W and the length direction L, thereby obtaining good results in the evaluation of moisture resistance reliability.

[0098] The corner outer layer portions CG adjacent to the first side outer layer portion WG1 or the second side outer layer portion WG2 in the length direction L and adjacent to the first end surface outer layer portion LG1 or the second end surface outer layer portion LG2 in the width direction W are located at the four corners of the stacked body 10 in a plan view. This region is an area covered by the external electrode 40 ( Figure 3 , Figure 4), and is therefore susceptible to stress due to the bending of the substrate, resulting in cracks and defects in the dielectric, and is a portion that is easily damaged in the stacked ceramic capacitor. However, by increasing the density of the dielectric in a given area of ​​the corner side outer layer CG, the mechanical strength can be improved and the reliability of the stacked ceramic capacitor can be improved.

[0099] In the corner outer layer portion CG, in the dielectric in the region DC surrounded by an imaginary surface obtained by extending the front end face of the internal electrode layer 30 on the opposite side to the side connected to the external electrode 40 in the width direction W, an imaginary surface obtained by extending the side face extending in the length direction L of the internal electrode layer 30 in the length direction L, the first side face WS1 or the second side face WS2, and the first end face LS1 or the second end face LS2,

[0100] The content ratio of Ba, Ti and Zr, Ba / (Ti+Zr), is 0.995 or more and 1.003 or less.

[0101] The content of Mg or Mn relative to 100 molar parts of Ti is 0.4 molar parts or more and 2.0 molar parts or less than the content of Mg or Mn relative to 100 molar parts of Ti in the dielectric region of the effective portion 11 in the central portion in the width direction W and the length direction L. In this case, the porosity becomes less than 3%, and the grain growth can be set to a sintered particle diameter of less than 0.5 μm, so that the density of the dielectric is improved, the mechanical strength can be improved, and the stacked ceramic capacitor can be effectively prevented from being damaged by cracks, defects, and the like.

[0102] In the first side outer layer portion WG1 or the second side outer layer portion WG2, in the dielectric of the region DW between the internal electrode layer 30 and the first side WS1 or between the internal electrode layer 30 and the second side WS2, it is appropriate to increase the content of Mg or Mn in the direction from the internal electrode layer 30 toward the first side WS or from the internal electrode layer 30 toward the second side WS2. By increasing the content of Mg or Mn, Mg and the like are present in the grain boundary, which can inhibit grain growth, promote densification and reduce the particle size. Thus, moisture resistance reliability and reliability (suppressing the generation of large particles) can be taken into account. In addition, the firing temperature is different between the side and the inside during sintering, so by increasing the content of Mg and the like toward the first side WS or the second side WS2, the densification and particle size deviation can be reduced.

[0103] It is suitable to form the structure as follows: that is, in the internal electrode layer 30, in a range of 5 μm from the end in the width direction W toward the center in the width direction W, as shown in FIG. Figure 7As shown, the thickness of the internal electrode layer 30 in the stacking direction T gradually decreases toward the end to form an inclined surface, and the dielectric 20a with a particle diameter of all particles of 500nm or less is stacked on the inclined surface. In this way, by configuring a dense dielectric on the side of the internal electrode layer 30, it is possible to prevent moisture infiltrated from the outside from reaching the internal electrode layer, and it is possible to have high moisture resistance reliability.

[0104] Description of Reference Numerals

[0105] 1 Multilayer Ceramic Capacitors

[0106] 10 Laminated body

[0107] 11 Effective part

[0108] 20 Dielectric layer

[0109] 20a Dielectric

[0110] 30 Internal electrode layer

[0111] 31 1st internal electrode layer

[0112] 31A First opposing part

[0113] 31B 1st lead

[0114] 32 2nd internal electrode layer

[0115] 32A Second opposing portion

[0116] 32B 2nd lead section

[0117] 40 External electrodes

[0118] 40A 1st external electrode

[0119] 40B 2nd external electrode

[0120] TS1 Main side 1

[0121] TS2 2nd main side

[0122] WS1 Side 1

[0123] WS2 Side 2

[0124] LS1 1st end face

[0125] LS2 2nd end face

[0126] TG Main surface side outer layer

[0127] TG1 1st main surface side outer layer

[0128] TG2 Second main surface side outer layer

[0129] WG Side outer layer

[0130] WG1 1st side outer layer

[0131] WG2 Second side outer layer

[0132] LG End surface side outer layer

[0133] LG1 1st end surface side outer layer

[0134] LG2 2nd end surface side outer layer

[0135] CG Corner outer layer

[0136] DC, DL, DW areas.

Claims

1. A laminated ceramic capacitor comprising a laminated body including a plurality of laminated dielectric layers and a plurality of internal electrode layers, and an external electrode arranged to be electrically connected to the internal electrode layers, wherein: The dielectric layer contains Ba, Ti and Zr, and contains Mg or Mn, The stacked body comprises a first main surface and a second main surface which are opposite to each other in a stacking direction of the dielectric layer and the internal electrode layer, a first side surface and a second side surface which are opposite to each other in a width direction which intersects both the stacking direction and a length direction in which the internal electrode layer extends toward the external electrode, and a first end surface and a second end surface which are opposite to each other in a length direction which intersects the stacking direction and the width direction. The external electrodes are respectively arranged on the first end surface and the second end surface, In the stacked body, when the area where the internal electrode layers overlap each other when viewed from the stacking direction is set as the effective part, the area opposite to the effective part sandwiched in the stacking direction is set as the first main surface side outer layer part and the second main surface side outer layer part, the area opposite to the effective part sandwiched in the width direction is set as the first side surface side outer layer part and the second side surface side outer layer part, and the area opposite to the effective part sandwiched in the length direction is set as the first end surface side outer layer part and the second end surface side outer layer part, In the central portion in the longitudinal direction of the first side surface outer layer portion or the second side surface outer layer portion, in the dielectric in the region between the first side surface or the second side surface and the internal electrode layer, The content ratio of Ba, Ti and Zr, Ba / (Ti+Zr), is 0.995 or more and 1.003 or less. The content of Mg relative to 100 molar parts of Ti is 0.5 molar parts or more and 5.0 molar parts or less than the content of Mg relative to 100 molar parts of Ti in the dielectric region of the effective portion located in the central portion in the width direction and the longitudinal direction, or the content of Mn relative to 100 molar parts of Ti is 0.4 molar parts or more and 2.0 molar parts or less than the content of Mn relative to 100 molar parts of Ti in the dielectric region of the effective portion located in the central portion in the width direction and the longitudinal direction, In the first end surface side outer layer portion or the second end surface side outer layer portion, in the dielectric in the region between the first end surface or the second end surface and the internal electrode layer, The content ratio of Ba, Ti and Zr, Ba / (Ti+Zr), is 0.995 or more and 1.003 or less. The content of Mg relative to 100 molar parts of Ti is 0.25 molar parts or more and 2.5 molar parts or less than the content of Mg relative to 100 molar parts of Ti in the dielectric of the effective portion in the central portion of the width direction and the length direction, or the content of Mn relative to 100 molar parts of Ti is 0.2 molar parts or more and 1.0 molar parts or less than the content of Mn relative to 100 molar parts of Ti in the dielectric of the effective portion in the central portion of the width direction and the length direction.

2. The multilayer ceramic capacitor according to claim 1, wherein When a region adjacent to the first side surface outer layer portion or the second side surface outer layer portion in the length direction and adjacent to the first end surface outer layer portion or the second end surface outer layer portion in the width direction is set as a corner side outer layer portion, In the corner side outer layer portion, in the dielectric in a region surrounded by an imaginary surface obtained by extending the front end face of the internal electrode layer on the side opposite to the side connected to the external electrode in the width direction, an imaginary surface obtained by extending the side face of the internal electrode layer extending in the length direction in the length direction, the first side face or the second side face, and the first end face or the second end face, The content ratio of Ba, Ti and Zr, Ba / (Ti+Zr), is 0.995 or more and 1.003 or less. The content of Mg or Mn per 100 mol parts of Ti is 0.4 mol parts or more and 2.0 mol parts or less than the content of Mg or Mn per 100 mol parts of Ti in the dielectric region of the effective portion in the central portion in the width direction and the longitudinal direction.

3. The multilayer ceramic capacitor according to claim 1 or 2, wherein: In the outer layer portion on the first side surface or the outer layer portion on the second side surface, in the dielectric in the area between the internal electrode layer and the first side surface or between the internal electrode layer and the second side surface, the content of Mg or Mn increases in the direction from the internal electrode layer toward the first side surface or from the internal electrode layer toward the second side surface.

4. The multilayer ceramic capacitor according to claim 1 or 2, wherein: In the internal electrode layer, within a range of 5 μm from the end in the width direction toward the center in the width direction, an inclined surface is formed in which the thickness of the internal electrode layer in the stacking direction gradually decreases toward the end, and the particle size of all particles of the dielectric stacked on the inclined surface is less than 500 nm.

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