JP6474930B2 - Multilayer ceramic capacitor - Google Patents

Description

  The present invention relates to a multilayer ceramic capacitor in which a first external electrode and a second external electrode are provided on one surface in the height direction of a substantially rectangular parallelepiped capacitor body.

  1 to 7 of Patent Document 1 described later disclose a multilayer ceramic capacitor related to the above. This monolithic ceramic capacitor is a substantially rectangular parallelepiped capacitor including a plurality of substantially rectangular first internal electrode layers and a plurality of substantially rectangular internal electrode layers alternately arranged in the width direction through dielectric layers. The main body includes a substantially rectangular first external electrode and a substantially rectangular second external electrode provided on one surface of the capacitor main body in the height direction. Each first internal electrode layer has a substantially rectangular first lead portion extending to one surface in the height direction of the capacitor body, and an end edge of each first lead portion is connected to the first external electrode. Each second internal electrode layer has a substantially rectangular second lead portion that extends to one surface in the height direction of the capacitor body, and an end edge of each second lead portion is connected to the second external electrode.

  The multilayer ceramic capacitor has a structure in which each first internal electrode layer and each second internal electrode layer are arranged in a direction substantially perpendicular to the first external electrode and the second external electrode. The lengthwise dimension (width) is narrower than the heightwise dimension (width) of each first internal electrode layer, and the lengthwise dimension (width) of each second lead portion is the same as that of each second internal electrode layer. It becomes narrower than the height direction dimension (width). Therefore, when trying to meet the demands for downsizing and large capacity in the multilayer ceramic capacitor, the connection of each first lead part to the first external electrode and the connection of each second lead part to the second external electrode are unstable. There is a concern to become.

  That is, in order to meet the demands for miniaturization and large capacity in the multilayer ceramic capacitor, the height direction dimension (width) and length direction of each first internal electrode layer and the height direction of each second internal electrode layer Although it is necessary to reduce the dimension (width) and the length dimension, the length dimension (width) of each first drawer part and the length direction of each second drawer part in particular with the reduction of the length dimension. Since the dimension (width) becomes extremely narrow, the connection of each first lead portion to the first external electrode and the connection of each second lead portion to the second external electrode tend to be unstable.

JP, 2014-116571, A

  The subject of the present invention is a case where a multilayer ceramic capacitor in which a first external electrode and a second external electrode are provided on one surface in the height direction of a substantially rectangular parallelepiped capacitor body meets the demand for miniaturization and large capacity. An object of the present invention is to provide a multilayer ceramic capacitor capable of realizing a highly reliable connection between the connection of each first internal electrode layer to the first external electrode and the connection of each second internal electrode layer to the second external electrode.

  In order to solve the above problems, a multilayer ceramic capacitor according to the present invention is a multilayer ceramic body in which a substantially rectangular first external electrode and a substantially rectangular second external electrode are provided on one surface in the height direction of a substantially rectangular parallelepiped capacitor body. The capacitor body includes (1) a plurality of substantially rectangular first internal electrode layers and a plurality of substantially rectangular second internal electrode layers that are alternately arranged via dielectric layers. A substantially rectangular parallelepiped capacitive element included therein, (2) a first coating layer covering one side in the width direction of the capacitive element, (3) a second coating layer covering the other side in the width direction of the capacitive element, and (4) A first relay layer that covers one surface in the length direction of the capacitive element and is in contact with one edge in the length direction of the first coating layer and one edge in the length direction of the second coating layer; Covering the other surface in the length direction, the other end in the length direction of the first coating layer and the second coating layer A second relay layer in contact with the other edge in the lengthwise direction; (6) a third coating layer covering the outer surface of the first relay layer; and (7) a fourth coating layer covering the outer surface of the second relay layer. The first relay layer includes a substantially rectangular conductive portion facing one end edge in the length direction of the plurality of first internal electrode layers, and one end edge in the height direction of the conductive portion. The second relay layer has a substantially rectangular conductive portion facing each other end in the longitudinal direction of the plurality of second internal electrode layers; and A conductive portion of the first relay layer surrounding the periphery excluding one edge in the height direction, and the conductive portion of the first relay layer includes a length direction of the plurality of first internal electrode layers. One end edge is connected with a connection width equal to the width of each of the plurality of first internal electrode layers, and the conductive layer of the second relay layer is connected. The other ends in the length direction of the plurality of second internal electrode layers are connected to the active portion with connection widths equal to the widths of the plurality of second internal electrode layers, respectively, One end edge in the height direction of the conductive portion of the first relay layer is connected with a connection width equal to the width of the conductive portion of the first relay layer, and the second external electrode is connected to the second external electrode. One end edge in the height direction of the conductive portion of the two relay layers is connected with a connection width equal to the width of the conductive portion of the second relay layer.

  According to the present invention, even when a multilayer ceramic capacitor in which a first external electrode and a second external electrode are provided on one surface in the height direction of a substantially rectangular parallelepiped capacitor body meets the demand for miniaturization and large capacity. In addition, it is possible to provide a multilayer ceramic capacitor capable of realizing a highly reliable connection between the connection of each first internal electrode layer to the first external electrode and the connection of each second internal electrode layer to the second external electrode.

FIG. 1 is a view of a multilayer ceramic capacitor to which the present invention is applied as viewed from the sixth surface f6 side of the capacitive element. 2 is a view of the multilayer ceramic capacitor shown in FIG. 1 as viewed from the third surface f3 side of the capacitive element. FIG. 3 is a view of the multilayer ceramic capacitor shown in FIG. 1 as viewed from the fifth surface f5 side of the capacitive element. 4 is a cross-sectional view taken along line S1-S1 of FIG. 5A is a cross-sectional view taken along line S2-S2 in FIG. 2, and FIG. 5B is a cross-sectional view taken along line S3-S3 in FIG. 6A and 6B are partially enlarged views of FIG. FIGS. 7A to 7C are diagrams for explaining an example of a method for manufacturing the multilayer ceramic capacitor shown in FIG. 8A and FIG. 8B are diagrams corresponding to FIG. 6 showing a modification of the multilayer ceramic capacitor shown in FIG.

  First, the structure of a multilayer ceramic capacitor to which the present invention is applied will be described with reference to FIGS. In this description, the horizontal direction in FIG. 1 is referred to as the length direction, the vertical direction in FIG. 1 is referred to as the width direction, the vertical direction in FIG. 2 is referred to as the height direction, and the length direction and width direction of each component. And the dimension along each height direction is called length, width, and height.

  This multilayer ceramic capacitor includes a substantially rectangular parallelepiped capacitor body 110, a substantially rectangular first external electrode 120 and a substantially rectangular second external electrode 130 provided on one surface of the capacitor body 110 in the height direction. The overall dimensions are defined by the length L, the width W, and the height H. Incidentally, the length L, width W, and height H of the multilayer ceramic capacitor shown in FIGS. 1 to 6 are, for example, 1000 μm, 500 μm, and 500 μm, or 600 μm, 300 μm, and 300 μm, respectively. 1 to 6 illustrate a multilayer ceramic capacitor in which the length L, the width W, and the height H are such that length L> width W = height H. These length L and width W are illustrated. And height H are length L> width W> height H, length L> height H> width W, width W> length L = height H, width W> length L > Height H or width W> height H> length L may be sufficient.

  The capacitor body 110 includes a capacitive element 111, a first coating layer 112, a second coating layer 113, a first relay layer 114, a second relay layer 115, a third coating layer 116, and a fourth coating layer 117. And is composed of.

  The capacitive element 111 has a substantially rectangular parallelepiped shape, and faces the first surface f1 and the second surface f2 facing in the length direction and the third surface f3 and the fourth surface f4 facing in the width direction in the height direction. It has the 5th surface f5 and the 6th surface f6. The capacitive element 111 includes a plurality of substantially rectangular first internal electrode layers 111a and a plurality of substantially rectangular second internal electrode layers 111b arranged alternately in the height direction via dielectric layers (reference numerals omitted). Contains. The width, length and thickness of each first internal electrode layer 111a and the width, length and thickness of each second internal electrode layer 111b are substantially the same, and the thickness of each dielectric layer is substantially the same. Incidentally, the thickness of each first internal electrode layer 111a and the thickness of each second internal electrode layer 111b are set within a range of 0.5 to 2 μm, for example, and the thickness of each dielectric layer is 0, for example. It is set within a range of 0.5 to 2 μm. As can be seen from FIG. 7A, the width of the capacitive element 111 is substantially the same as the width of each of the first internal electrode layer 111a and the second internal electrode layer 111b, and the capacitive element 111 is on the fifth surface f5 side. And the sixth surface f6 side have margin portions (reference numerals omitted). 1 to FIG. 6, 10 layers of the first internal electrode layer 111a and the second internal electrode layer 111b are respectively drawn for convenience of illustration, and the first internal electrode layer 111a is illustrated. The number of second internal electrode layers 111b may be 11 or more.

  The portion of the capacitive element 111 excluding each first internal electrode layer 111a and each second internal electrode layer 111b has barium titanate, strontium titanate, calcium titanate, magnesium titanate, calcium zirconate, and calcium zirconate titanate. Dielectric ceramics mainly composed of barium zirconate, titanium oxide, etc., preferably high dielectric constant dielectric ceramics having a relative dielectric constant of 1000 or more can be used. Further, a good conductor mainly composed of nickel, copper, palladium, platinum, silver, gold, an alloy thereof, or the like can be used for each first internal electrode layer 111a and each second internal electrode layer 111b.

  The first coating layer 112 has a substantially rectangular shape and covers the third surface f3 of the capacitive element 111 in a close contact state. The length and height of the first coating layer 112 are substantially the same as the length and height of the third surface f3. Since the thickness of the first coating layer 112 is related to the width of the capacitor body 110, it is desirable that the thickness is as thin as possible. Incidentally, the thickness of the first coating layer 112 is set within a range of 1 to 20 times the thickness of the third coating layer 116 or the thickness of the fourth coating layer 117, which will be described later, preferably 5 to 20 μm. Is set within the range. In addition, the first coating layer 112 has a dielectric material mainly composed of barium titanate, strontium titanate, calcium titanate, magnesium titanate, calcium zirconate, calcium zirconate titanate, barium zirconate, titanium oxide and the like. Ceramics, preferably a high dielectric constant dielectric ceramic having a relative dielectric constant of 1000 or more, more preferably the same main component as the main component of the capacitive element 111 excluding the first internal electrode layer 111a and the second internal electrode layer 111b Dielectric ceramics can be used.

  The second coating layer 113 has a substantially rectangular shape, and covers the fourth surface f4 of the capacitive element 111 in a close contact state. The length and height of the second coating layer 113 are substantially the same as the length and height of the fourth surface f4. Since the thickness of the second coating layer 113 is related to the width of the capacitor body 110, it is desirable that the thickness is as thin as possible. Incidentally, the thickness of the second coating layer 113 is set within a range of 1 to 20 times the thickness of the third coating layer 116 or the thickness of the fourth coating layer 117, which will be described later, preferably 5 to 20 μm. Is set within the range. In addition, the second coating layer 113 has a dielectric material mainly composed of barium titanate, strontium titanate, calcium titanate, magnesium titanate, calcium zirconate, calcium zirconate titanate, barium zirconate, titanium oxide and the like. Ceramics, preferably a high dielectric constant dielectric ceramic having a relative dielectric constant of 1000 or more, more preferably the same main component as the main component of the capacitive element 111 excluding the first internal electrode layer 111a and the second internal electrode layer 111b Dielectric ceramics can be used.

  The first relay layer 114 has a substantially rectangular shape, covers the first surface f1 of the capacitive element 111 in a close contact state, one end edge in the length direction of the first coating layer 112, and the length of the second coating layer 113. It is in contact with one edge in the vertical direction. The width of the first relay layer 114 is substantially the same as the sum of the width of the first surface f1 of the capacitive element 111, the thickness of the first covering layer 112, and the thickness of the second covering layer 113. The height of the first relay layer 114 is substantially the same as the height of the first surface f1 of the capacitive element 111. Since the thickness of the first relay layer 114 is related to the length of the capacitor body 110, it is desirable that the thickness is as thin as possible. Incidentally, the thickness of the first relay layer 114 is set, for example, within a range of 1 to 5 times the thickness of the first internal electrode layer 111a, and preferably within a range of 0.5-5 μm. Yes.

  As shown in FIGS. 4 and 5A, the first relay layer 114 includes a substantially rectangular conductive portion 114a facing one end edge in the length direction of each first internal electrode layer 111a of the capacitor 111, and The conductive portion 114a has a substantially U-shaped hardly conductive portion 114b surrounding a peripheral edge excluding one edge in the height direction. Here, “difficult conductivity” means that the conductivity is lower than that of the conductive portion 114a, and it means that there is almost no conductivity. For the conductive portion 114a, a good conductor mainly composed of nickel, copper, or an alloy thereof can be used. Preferably, a good conductor having the same main component as the main component of each of the first internal electrode layer 111a and the second internal electrode layer 112a is used. Can be used. Further, the hardly conductive portion 114b includes a component for reducing conductivity, preferably a metal oxide which is a main component of the conductive portion 114a, specifically nickel oxide, nickel magnesium composite oxide, or the like. Things can be used. One end edge in the length direction of each first internal electrode layer 111a is connected to the conductive portion 114a of the first relay layer 114 with a connection width equivalent to the width of each first internal electrode layer 111a. Note that the connection width of one edge in the length direction of each first internal electrode layer 111a to the conductive portion 114a of the first relay layer 114 is ideally the width of each first internal electrode layer 111a, but it is an actual one. Then, since the fluctuation of about ± 5% of the width of each first internal electrode layer 111a was confirmed in the width of one edge in the longitudinal direction of each first internal electrode layer 111a, here, “ Instead of expressing “the same connection width as the width”, it is expressed as “a connection width equivalent to the width of each first internal electrode layer 111a”.

  The second relay layer 115 has a substantially rectangular shape, the second surface f2 of the capacitive element 111, the other edge in the length direction of the first coating layer 112, the length direction of the second coating layer 113, and the like. The edges are covered in close contact. The width of the second relay layer 115 is substantially the same as the sum of the width of the second surface f2 of the capacitive element 111, the thickness of the first covering layer 112, and the thickness of the second covering layer 113. The height of the second relay layer 115 is substantially the same as the height of the second surface f2 of the capacitive element 111. Since the thickness of the second relay layer 115 is related to the length of the capacitor body 110, it is desirable that the thickness is as thin as possible. Incidentally, the thickness of the second relay layer 115 is set within a range of, for example, 1 to 5 times the thickness of the second internal electrode layer 111b, and preferably within a range of 0.5 to 5 μm. Yes.

  As shown in FIGS. 4 and 5B, the second relay layer 115 includes a substantially rectangular conductive portion 115a facing the other end in the length direction of each second internal electrode layer 111b of the capacitive element 111. The conductive portion 115a has a substantially U-shaped hardly conductive portion 115b surrounding a peripheral edge excluding one edge in the height direction. Here, “difficult conductivity” means that the conductivity is lower than that of the conductive portion 115a, and it means that there is almost no conductivity. For the conductive portion 115a, a good conductor mainly composed of nickel, copper, or an alloy thereof can be used. Preferably, a good conductor having the same main component as the main components of the first internal electrode layer 111a and the second internal electrode layer 112a is used. Can be used. Further, the hardly conductive portion 115b includes a component for reducing conductivity, preferably a metal oxide which is a main component of the conductive portion 115a, specifically nickel oxide, nickel magnesium composite oxide, or the like. Things can be used. The other end edge in the length direction of each second internal electrode layer 111b is connected to the conductive portion 115a of the second relay layer 115 with a connection width equivalent to the width of each second internal electrode layer 111b. It should be noted that the connection width of the other end in the longitudinal direction of each second internal electrode layer 111b with respect to the conductive portion 115a of the second relay layer 115 is ideally the width of each second internal electrode layer 111b. In the present embodiment, since the variation of the width of each first internal electrode layer 111a by about ± 5% was confirmed in the width of the other edge in the length direction of each second internal electrode layer 111b, the “second second internal electrode layer” It is expressed as “a connection width equivalent to the width of each second internal electrode layer 111b” instead of “the same connection width as the width of 111b”.

  The third coating layer 116 has a substantially rectangular shape and covers the outer surface of the first relay layer 114 in a close contact state. The width and height of the third coating layer 116 are substantially the same as the width and height of the outer surface of the first relay layer 114. Since the thickness of the third coating layer 116 is related to the length of the capacitor body 110, it is desirable that the thickness is as thin as possible. Incidentally, the thickness of the third coating layer 116 is set within a range of 1 to 10 times the thickness of the dielectric layer interposed between the first internal electrode layer 111a and the second internal electrode layer 111b, for example. Preferably, it is set within a range of 1 to 10 μm. The third coating layer 116 has a dielectric material mainly composed of barium titanate, strontium titanate, calcium titanate, magnesium titanate, calcium zirconate, calcium zirconate titanate, barium zirconate, titanium oxide and the like. Ceramics, preferably a high dielectric constant dielectric ceramic having a relative dielectric constant of 1000 or more, more preferably the same main component as the main component of the capacitive element 111 excluding the first internal electrode layer 111a and the second internal electrode layer 111b Dielectric ceramics can be used.

  The fourth coating layer 117 has a substantially rectangular shape, and covers the outer surface of the second relay layer 115 in a close contact state. The width and height of the fourth coating layer 117 are substantially the same as the width and height of the outer surface of the second relay layer 115. Since the thickness of the fourth coating layer 117 is related to the length of the capacitor body 110, it is desirable that the thickness is as thin as possible. Incidentally, the thickness of the fourth covering layer 117 is set within a range of 1 to 10 times the thickness of the dielectric layer interposed between the first internal electrode layer 111a and the second internal electrode layer 111b, for example. Preferably, it is set within a range of 1 to 10 μm. The fourth coating layer 117 includes a dielectric material mainly composed of barium titanate, strontium titanate, calcium titanate, magnesium titanate, calcium zirconate, calcium zirconate titanate, barium zirconate, titanium oxide, and the like. Ceramics, preferably a high dielectric constant dielectric ceramic having a relative dielectric constant of 1000 or more, more preferably the same main component as the main component of the capacitive element 111 excluding the first internal electrode layer 111a and the second internal electrode layer 111b Dielectric ceramics can be used.

  The first external electrode 120 has a substantially rectangular shape, and is provided in close contact with the third coating layer 116 side of the fifth surface f5 of the capacitive element 111 corresponding to one surface of the capacitor body 110 in the height direction. . The width of the first external electrode 120 is substantially the same as the sum of the width of the fifth surface f5 of the capacitive element 111, the thickness of the first covering layer 112, and the thickness of the second covering layer 113. The length of the first external electrode 120 is set, for example, within a range of 1/8 to 1/3 of the length L of the multilayer ceramic capacitor, and the thickness is set within a range of, for example, 1-15 μm. In addition, one end edge in the length direction of the first external electrode 120 reaches below the outer surface of the third coating layer 116. One end edge in the height direction of the conductive portion 114 a of the first relay layer 114 is connected to the first external electrode 120 with a connection width equal to the width of the conductive portion 114 a of the first relay layer 114. The connection width of the one end edge in the height direction of the conductive portion 114a of the first relay layer 114 with respect to the first external electrode 120 is ideally the width of the conductive portion 114a of the first relay layer 114. In this case, since a variation of about ± 5% of the width of the conductive portion 114a of the first relay layer 114 was confirmed in the width of the one end edge in the height direction of the conductive portion 114a of the first relay layer 114, the “first Instead of expressing “the same connection width as the width of the conductive portion 114 a of the first relay layer 114”, it is expressed as “the connection width equivalent to the width of the conductive portion 114 a of the first relay layer 114”.

  The second external electrode 130 has a substantially rectangular shape and is provided in close contact with the fourth coating layer 117 side of the fifth surface f5 of the capacitive element 111 corresponding to one surface in the height direction of the capacitor body 110. . The width of the second external electrode 130 is substantially the same as the sum of the width of the fifth surface f5 of the capacitive element 111, the thickness of the first covering layer 112, and the thickness of the second covering layer 113. The length of the second external electrode 130 is set, for example, within a range of 1/8 to 1/3 of the length L of the multilayer ceramic capacitor, and the thickness is set within a range of, for example, 1-15 μm. In addition, the other end in the length direction of the second external electrode 130 reaches below the outer surface of the fourth coating layer 117. One end edge in the height direction of the conductive portion 115 a of the second relay layer 115 is connected to the second external electrode 130 with a connection width equal to the width of the conductive portion 115 a of the second relay layer 115. The connection width of one end edge in the height direction of the conductive portion 115a of the second relay layer 115 to the second external electrode 130 is ideally the width of the conductive portion 115a of the second relay layer 115. In this case, since a variation of about ± 5% of the width of the conductive portion 115a of the second relay layer 115 can be confirmed in the width of the one end edge in the height direction of the conductive portion 115a of the second relay layer 115, here, “ It is expressed as “a connection width equivalent to the width of the conductive portion 115a of the second relay layer 115” instead of “the same connection width as the width of the conductive portion 115a of the second relay layer 115”.

  Here, using FIGS. 5 and 6, the aspect of the first external electrode 120 and the second external electrode 130 will be supplemented.

  The first external electrode 120 shown in FIG. 6A is in close contact with (5) the fifth surface f5 of the capacitive element 111, and one edge in the height direction of the first coating layer 112 and the height of the second coating layer 113. A base film 121 in contact with one edge in the direction, one edge in the height direction of the first relay layer 114, and one edge in the height direction of the third coating layer 116; and (2) an intermediate film 122 in close contact with the outer surface of the base film 121. And (3) a three-layer structure having a surface film 123 in close contact with the outer surface of the intermediate film 122. 6B is in close contact with the fifth surface f5 of the capacitive element 111, and one end edge in the height direction of the first coating layer 112 and the second coating layer 113. A base film 131 in contact with one end edge in the height direction, one end edge in the height direction of the second relay layer 115 and one end edge in the height direction of the fourth coating layer 117; and (2) an intermediate portion in close contact with the outer surface of the base film 131 It has a three-layer structure including a film 132 and (3) a surface film 133 in close contact with the outer surface of the intermediate film 132.

  The base films 121 and 131 are made of, for example, a baked film, and a good conductor mainly composed of nickel, copper, palladium, platinum, silver, gold, or an alloy thereof can be used for the baked film. The intermediate films 122 and 132 are made of, for example, a plating film, and a good conductor mainly composed of platinum, palladium, gold, copper, nickel, alloys thereof, or the like can be used for the plating film. The surface films 123 and 133 are made of, for example, a plating film, and a good conductor mainly composed of copper, tin, palladium, gold, zinc, alloys thereof, or the like can be used for the plating film. The first external electrode 120 and the second external electrode 130 do not necessarily have a three-layer structure, and a two-layer structure excluding the intermediate films 122 and 132 or a multilayer structure in which the intermediate films 122 and 132 are two or more layers. Alternatively, a single layer structure having only the surface films 123 and 133 may be used.

  Next, an example of a manufacturing method suitable for the above-described multilayer ceramic capacitor will be described using FIG. 7 and appropriately using the reference numerals shown in FIGS.

  During production, a first ceramic slurry containing a dielectric ceramic powder, an organic binder, an organic solvent and various additives, and an oxidation promoter such as MgO are added to the first ceramic slurry within a range of 0.1 to 30 at%. An electrode paste containing the second ceramic slurry, a good conductor powder, an organic binder, an organic solvent and various additives, and a conductor paste containing only the good conductor powder, the organic binder and the organic solvent are prepared.

  Subsequently, a first ceramic slurry is applied to the surface of the carrier film and dried to produce a first sheet. Moreover, the 2nd sheet in which the internal electrode layer pattern group was formed is produced by printing and drying an electrode paste on the surface of the 1st sheet. Furthermore, the 3rd sheet in which the conductor layer pattern group was formed is produced by printing and drying a conductor paste on the surface of the 1st sheet. Furthermore, a 4th sheet | seat is produced by apply | coating a 2nd ceramic slurry to the surface of a carrier film, and drying.

  Subsequently, the unit sheet taken out from the first sheet is repeatedly stacked and thermocompression bonded until a predetermined number of sheets are reached, thereby forming a portion corresponding to one margin portion of the capacitive element 111 in the height direction. Subsequently, the unit sheets (including the internal electrode layer pattern group) taken out from the second sheet are stacked and thermocompression bonded until a predetermined number of sheets are reached, thereby repeating the first internal electrode layer 111a and the second internal electrode layer 111a of the capacitive element 111. A portion corresponding to a portion where the internal electrode layer 111b exists is formed. Subsequently, a unit corresponding to the other margin part in the height direction of the capacitive element 111 is formed by repeating the operation of stacking the unit sheets taken out from the fourth sheet until the predetermined number is reached and thermocompression bonding. Finally, an unfired sheet is produced by subjecting the entire stacked body to thermocompression bonding.

  Subsequently, an unsintered element CE corresponding to the capacitor 111 is manufactured by cutting the unsintered sheet into a lattice shape (see FIG. 7A). This unfired element CE has a plurality of unfired internal electrode layers IEL1 and IEL2 to be the first internal electrode layer 111a and the second internal electrode layer 111b, and also has a height of an unfired margin portion CEa containing an oxidation accelerator. It has in the direction other side.

  Subsequently, after aligning the direction of the unfired element CE shown in FIG. 7A, the fourth sheet is pressed against the one surface in the width direction and the other surface in the width direction to perform thermocompression bonding. By cutting, an unsintered coating layer DL1 serving as the first coating layer 112 is formed on one surface in the width direction of the unfired element CE, and an unsintered coating layer DL2 serving as the second coating layer 113 is formed on the other surface in the width direction. (See FIG. 7B). The unsintered coating layers DL1 and DL2 contain an oxidation accelerator.

  Subsequently, after aligning the orientation shown in FIG. 7B, the conductor layer pattern group side of the third sheet is pressed against the one surface in the length direction and the other surface in the length direction, followed by thermocompression bonding. By cutting the third sheet, the unfired conductor layer CL1 and the unfired coating layer DL3, which become the first relay layer 114 and the third coating layer 116, are formed on one surface in the length direction of the one shown in FIG. 7B. At the same time, the unfired conductor layer CL2 and the unfired coating layer DL4 to be the second relay layer 115 and the fourth cover layer 117 are formed on the other surface in the length direction (see FIG. 7C).

  Subsequently, a large number of the ceramics shown in FIG. 7C are fired together in an atmosphere corresponding to the dielectric ceramic powder and good conductor powder contained therein, and in a temperature profile (binder removal treatment and firing treatment). And barrel-polishing as many as needed. Thereby, the capacitor body 110 is manufactured.

  In the firing step, when the good conductor powder contained in each of the unfired conductor layers CL1 and CL2 shown in FIG. 7C is, for example, nickel powder, the unfired margin portion CEa of the unfired conductor layers CL1 and CL2 and Nickel oxide is positively generated at the portions in contact with the unsintered coating layer DL1 and the unsintered coating layer DL2, thereby changing the same portion into a hardly conductive portion. That is, the unfired conductor layer CL1 and the unfired conductor layer CL2 shown in FIG. 7C are subjected to the firing process, and the first relay layer 114 having the conductive portion 114a and the hardly conductive portion 114b (see FIG. A)), a second relay layer 115 (see FIG. 5B) having a conductive portion 115a and a hardly conductive portion 115b is obtained.

  Subsequently, after aligning the orientation of the capacitor body 110, an electrode paste (the same paste as the electrode paste or another paste having a different kind of good conductor powder) is applied or printed on one surface in each height direction. After drying, a baking process is performed to form the base films 121 and 131. Subsequently, the intermediate films 122 and 132 and the surface films 123 and 133 covering the base films 121 and 131 are formed by plating, and the first external electrode 120 and the second external electrode 130 are manufactured.

  Next, main effects (effects e1 and e2) obtained by the above-described multilayer ceramic capacitor will be described.

  (E1) The capacitor body 110 includes (1) a plurality of substantially rectangular first internal electrode layers 111a and a plurality of substantially rectangular second internal electrode layers 111b arranged alternately via dielectric layers. A substantially rectangular parallelepiped capacitive element 111, (2) a first coating layer 112 covering one surface in the width direction of the capacitor element 111, (3) a second coating layer 113 covering the other surface in the width direction of the capacitor element 111, 4) a first relay layer 114 that covers one surface in the length direction of the capacitive element 111 and is in contact with one end edge in the length direction of the first covering layer 112 and one end edge in the length direction of the second covering layer 113; A second relay layer 115 that covers the other longitudinal surface of the element 111 and is in contact with the other longitudinal edge of the first coating layer 112 and the other longitudinal edge of the second coating layer 113; (6) a first A third covering layer 116 covering the outer surface of the relay layer 114; and (7) covering an outer surface of the second relay layer 115. 4 coating layer 117 is composed of a.

  The first relay layer 114 has a substantially rectangular conductive portion 114a facing each of one end edge in the length direction of the plurality of first internal electrode layers 111a, and a peripheral edge excluding one end edge in the height direction of the conductive portion 114a. The second relay layer 115 includes a substantially rectangular conductive portion 115a facing each of the other end in the length direction of the plurality of second internal electrode layers 111b, and a conductive layer. The portion 115a has a non-conductive portion 115b surrounding the periphery except for one edge in the height direction. Further, one end edge in the length direction of the plurality of first internal electrode layers 111a is connected to the conductive portion 114a of the first relay layer 114 with a connection width equivalent to the width of each of the plurality of first internal electrode layers 111a. The other end edges in the length direction of the plurality of second internal electrode layers 111b are connected to the conductive portions 115a of the second relay layer 115 with connection widths equivalent to the widths of the plurality of second internal electrode layers 111b. It is connected. Further, one end edge in the height direction of the conductive portion 114a of the first relay layer 114 is connected to the first external electrode 120 with a connection width equal to the width of the conductive portion 114a of the first relay layer 114. One end edge in the height direction of the conductive portion 115 a of the second relay layer 115 is connected to the two external electrodes 130 with a connection width equivalent to the width of the conductive portion 115 a of the second relay layer 115.

  That is, the conductive portion 114a of the first relay layer 114 that serves to connect the first internal electrode layers 111a to the first external electrodes 120 by utilizing the respective widths of the capacitor body 110 and the second internal electrode layers. Since the conductive portion 115a of the second relay layer 115 serving to connect the 111b to the second external electrode 130 by utilizing each width is provided, the width and length of each first internal electrode layer 111a and each of the first internal electrode layers 111a are provided. Even if the width and length of the two internal electrode layers 111b are reduced, the connection of each first internal electrode layer 111a to the first external electrode 120 and the connection of each second internal electrode layer 111b to the second external electrode 130 are unstable. Can be avoided as much as possible. Therefore, even if the multilayer ceramic capacitor in which the first external electrode 120 and the second external electrode 130 are provided on one surface in the height direction of the substantially rectangular parallelepiped capacitor main body 110 meets the demand for miniaturization and large capacity. The connection of each first internal electrode layer 111 a to the first external electrode 120 and the connection of each second internal electrode layer 111 b to the second external electrode 130 can be realized with high reliability.

  The capacitor body 110 includes a third coating layer 116 that covers the outer surface of the first relay layer 114 and a fourth coating layer 117 that covers the outer surface of the second relay layer 115. The first relay layer 114 includes The conductive portion 114a has a hardly conductive portion 114b surrounding a peripheral edge except for one edge in the height direction, and the second relay layer 115 has a hard conductive portion 115b surrounding the peripheral edge except the one edge in the height direction of the conductive portion 115a. have. That is, even when the multilayer ceramic capacitor falls down when mounted on the circuit board, the conductive portion 114a of the first relay layer 114 and the conductive portion 115a of the second relay layer 115 are connected to the conductor lines of the circuit board, adjacent electronic components, etc. It is possible to surely prevent a problem such as a short circuit from coming into contact with the battery.

  (E2) The poorly conductive portions 114b and 115b of the first relay layer 114 and the second relay layer 115 of the capacitor body 110 are components for reducing conductivity, preferably the first relay layer 114 and the second relay layer 115. Since the metal oxide which is the main component of the respective conductive portions 114a and 115a is included, the conductivity of the hardly conductive portions 114b and 115b is made higher than the conductivity of the conductive portions 114a and 115a by this metal oxide. Can be reduced easily and reliably.

<Modification>
Next, modified examples (modified examples m1 and m2) of the above-described multilayer ceramic capacitor will be described.

  (M1) FIGS. 1 to 6 show the first covering layer 112 having a height substantially the same as the height of the third surface f3 of the capacitive element 111, and the second covering layer 113 has a height that is a capacity. Although the same height as that of the fourth surface f5 of the element 111 is shown, the widths of the first external electrode 120 and the second external electrode 130 at both ends in the length direction of one edge of the first coating layer 112 in the height direction are shown. A substantially rectangular projecting portion extending to one edge in the direction is provided, and each of the first external electrode 120 and the second external electrode 130 in the width direction is provided at both ends in the length direction of the second coating layer 113 in the height direction. You may make it provide the substantially rectangular overhang | projection part which extends to an edge. In this way, although the width of each of the first external electrode 120 and the second external electrode 130 is somewhat narrowed, at least a part in the thickness direction of one edge in the width direction of the first external electrode 120 and the second external electrode 130 is the first. It is also possible to cover each overhanging portion of the first covering layer 112, and at least a part in the thickness direction of the other edge in the width direction of the first external electrode 120 and the second external electrode 130 is covered with each overhanging portion of the second covering layer 113. It is also possible to cover with parts.

  (M2) In FIGS. 1 to 6, one end in the length direction of the first external electrode 120 reaches the outer surface of the third coating layer 116, and the other end in the length direction of the second external electrode 130 is the fourth coating layer. Although it has shown what has reached the outer surface of 117, as shown to FIG. 8 (A) and FIG. 8 (B), the height of each of the 1st relay layer 114 and the 3rd coating layer 116 was increased. The increased amount protrudes downward in the drawing from the fifth surface f5 of the capacitive element 111, and the height of each of the second relay layer 115 and the fourth covering layer 117 is increased to increase the increased amount of the capacitive element 111. You may make it protrude in the figure lower side rather than the 5th surface f5. In this way, at least a portion in the thickness direction of one end edge in the length direction of the first external electrode 120 can be covered with the protruding portions of the first relay layer 114 and the third covering layer 116, and the second external electrode It is also possible to cover at least a part in the thickness direction at the other end in the length direction of the electrode 130 with the protruding portions of the second relay layer 115 and the fourth coating layer 117. Further, by combining the modified example m1 with the modified example m2, it is possible to cover at least a part in the thickness direction of both the widthwise both ends and the lengthwise one end edge of the first external electrode 120, and the second external electrode It is also possible to cover at least a part in the thickness direction of the both ends in the width direction and the other end in the length direction of the electrode 130.

  DESCRIPTION OF SYMBOLS 110 ... Capacitor main body, 111 ... Capacitance element, 111a ... 1st internal electrode layer, 111b ... 2nd internal electrode layer, 112 ... 1st coating layer, 113 ... 2nd coating layer, 114 ... 1st relay layer, 114a ... 1st 1 conductive layer of the relay layer, 114b ... the poorly conductive part of the first relay layer, 115 ... the second relay layer, 115a ... the conductive part of the second relay layer, 115b ... the poorly conductive part of the second relay layer, 116 ... third coating layer, 117 ... fourth coating layer, 120 ... first external electrode, 130 ... second external electrode.

Claims (3)

A monolithic ceramic capacitor in which a substantially rectangular first external electrode and a substantially rectangular second external electrode are provided on one surface in the height direction of a substantially rectangular parallelepiped capacitor body,
The capacitor body includes (1) a substantially rectangular parallelepiped capacitive element including a plurality of first internal electrode layers and a plurality of second internal electrode layers alternately arranged via dielectric layers, and (2) A first covering layer covering one surface in the width direction of the capacitive element; (3) a second covering layer covering the other surface in the width direction of the capacitive element; and (4) covering one surface in the length direction of the capacitive element. A first relay layer in contact with one end edge in the length direction of the covering layer and one end edge in the length direction of the second covering layer; (5) covering the other surface in the length direction of the capacitive element; A second relay layer in contact with the other end in the length direction and the other end in the length direction of the second coating layer; (6) a third coating layer covering an outer surface of the first relay layer; A fourth covering layer covering the outer surface of the second relay layer,
The first relay layer has a substantially rectangular conductive portion facing each of one end edge in the length direction of the plurality of first internal electrode layers, and hardly conductive surrounding a peripheral edge excluding one end edge in the height direction of the conductive portion. And the second relay layer has a substantially rectangular conductive portion facing each other end in the longitudinal direction of the plurality of second internal electrode layers, and one end in the height direction of the conductive portion. A non-conductive part surrounding the periphery except the edge,
One end edge in the length direction of the plurality of first internal electrode layers is connected to the conductive portion of the first relay layer, and the plurality of second internal layers are connected to the conductive portion of the second relay layer. Each other end in the length direction of the internal electrode layer is connected,
The first relay layer and the third cover layer each have a protruding portion that protrudes from one surface in the height direction of the capacitive element, and the second relay layer and the fourth cover layer have a height of the capacitive element. Each has a protruding part that protrudes from one side in the direction,
One end edge in the length direction of the first external electrode is connected to the conductive portion of the protruding portion of the first relay layer, and the conductive portion of the protruding portion of the second relay layer includes the The other end in the length direction of the second external electrode is connected,
Multilayer ceramic capacitor. Each of the hardly conductive portions of the first relay layer and the second relay layer includes a component for reducing conductivity.
The multilayer ceramic capacitor according to claim 1. The component for reducing the conductivity is a metal oxide that is a main component of each of the conductive portion of the first relay layer and the conductive portion of the second relay layer.
The multilayer ceramic capacitor according to claim 2.

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