Multilayer ceramic capacitors and mounting structures

Abstract

To provide a multilayer ceramic capacitor with which it is possible to reduce the squeak noise of substrates.SOLUTION: A multilayer ceramic capacitor 1 comprises: a laminate 2 that includes a first plane 7a and a second plane 7b, a first end face 8a and a second end face 8b, and a first side face 9a and a second side face 9b; a first side margin part 3a that is located to the first side face 9a and has a first outside face 3aa; and a first external electrode 4a and a second external electrode 4b. Each of the first external electrode 4a and the second external electrode 4b includes a first section 41 that is located on the first plane 7a and a second section 42 that is located on the first outside face 3aa. The first section 41 includes a first electrode face 41a, and the second section 42 includes a second electrode face 42a. The first outside face 3aa includes an exposed region 3ac that is not covered by the second section 42. An interval s1 between the second electrode face 42a and the exposed region 3ac is smaller than an interval s2 between the first electrode face 41a and the first plane 7a.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a multilayer ceramic capacitor and a mounting structure.

Background Art

[0002] A multilayer ceramic capacitor includes a laminate in which dielectric layers and internal electrode layers are alternately laminated. Multilayer ceramic capacitors are usually mounted on a substrate and used. However, when the multilayer ceramic capacitor is driven, the dielectric layer expands and contracts due to the electrostriction effect, causing the substrate to bend and the substrate to make a ringing sound. In recent years, miniaturization of multilayer ceramic capacitors has been promoted. However, even in the case of a miniaturized multilayer ceramic capacitor, a thin-layered and highly laminated multilayer ceramic capacitor may cause the substrate to make a ringing sound.

[0003] Various multilayer ceramic capacitors for reducing the ringing sound of the substrate have been proposed. For example, Patent Document 1 discloses a multilayer ceramic capacitor that reduces the ringing sound of the substrate by making the thickness of the outer layer portion on the side facing the substrate thicker than the thickness of the outer layer portion on the side opposite to the side facing the substrate.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Conventional multilayer ceramic capacitors had room for improvement in reducing the ringing sound of the substrate.

Means for Solving the Problems

[0006] The multilayer ceramic capacitor of this disclosure is a substantially rectangular parallelepiped laminate in which dielectric layers and internal electrode layers are alternately stacked, and the laminate has a first and second surface facing each other, a first and second side surface facing each other, and a first and second end surface facing each other. A first side margin portion located on the first side surface and having a first outer surface opposite to the first side surface, A second side margin portion located on the second side and having a second outer surface opposite to the second side, A first external electrode is located extending from the first end face to the first surface, the second surface, the first outer surface, and the second outer surface, The present invention includes a second external electrode located from the second end face to the first face, the second face, the first outer surface, and the second outer surface, The first external electrode and the second external electrode are connected to different internal electrode layers of the internal electrode layer, The first external electrode and the second external electrode each have a first portion located on the first surface and a second portion located on the first outer surface, The first portion of the series has a first electrode surface opposite to the first surface side, The second portion has a second electrode surface opposite to the first outer surface side, The first outer surface has a covered area covered by the second portion and an exposed area not covered by the second portion. The distance between the second electrode surface and the exposed area in a direction perpendicular to the first side surface is smaller than the distance between the first electrode surface and the first surface in a direction perpendicular to the first surface.

[0007] The implementation structure of this disclosure includes the above-mentioned multilayer ceramic capacitor, A substrate having a mounting surface, The multilayer ceramic capacitor is mounted on the substrate such that the first side surface faces the mounting surface. [Effects of the Invention]

[0008] According to the multilayer ceramic capacitor and mounting structure of the present disclosure, the ringing of the substrate can be reduced.

Brief Description of the Drawings

[0009] [Figure 1] It is a perspective view showing a multilayer ceramic capacitor according to an embodiment of the present disclosure. [Figure 2] It is a cross-sectional view taken along the cutting plane line II-II of FIG. 1. [Figure 3] It is a cross-sectional view taken along the cutting plane line III-III of FIG. 1. [Figure 4] It is a cross-sectional view showing another example of a multilayer ceramic capacitor according to an embodiment of the present disclosure. [Figure 5] It is a cross-sectional view showing another example of a multilayer ceramic capacitor according to an embodiment of the present disclosure. [Figure 6] It is a cross-sectional view showing another example of a multilayer ceramic capacitor according to an embodiment of the present disclosure. [Figure 7A] It is a perspective view showing the manufacturing process of a temporary laminate. [Figure 7B] It is a perspective view showing a mother laminate. [Figure 7C] It is a perspective view showing a plurality of laminate precursors obtained by cutting a mother laminate. [Figure 8A] It is a side view showing the configuration of an apparatus for forming a side margin portion on the side surface of a laminate precursor. [Figure 8B] It is a side view showing the process of forming a side margin portion on the side surface of a laminate precursor. [Figure 8C] It is a side view showing the process of forming a side margin portion on the side surface of a laminate precursor. [Figure 9] It is a perspective view showing a main body portion. [Figure 10] It is a perspective view showing a mounting structure according to an embodiment of the present disclosure. [Figure 11] It is a cross-sectional view taken along the cutting plane line XI-XI of FIG. 10.

Embodiments for Carrying Out the Invention

[0010] Hereinafter, embodiments of the multilayer ceramic capacitor and the mounting structure of the present disclosure will be described while referring to the drawings. The drawings referred to below are schematic, and the dimensional ratios and the like shown in the drawings are not necessarily exactly as illustrated. Also, in this specification, for convenience, a rectangular coordinate system XYZ is defined. The X-axis direction is also referred to as the first direction or the length direction. The Y-axis direction is also referred to as the second direction or the width direction. The Z-axis direction is also referred to as the third direction or the height direction.

[0011] FIG. 1 is a perspective view showing a multilayer ceramic capacitor according to an embodiment of the present disclosure, FIG. 2 is a cross-sectional view taken along the cutting plane line II-II of FIG. 1, and FIG. 3 is a cross-sectional view taken along the cutting plane line III-III of FIG. 1. FIGS. 4 to 6 are cross-sectional views showing other examples of the multilayer ceramic capacitor according to an embodiment of the present disclosure. The cross-sectional views shown in FIGS. 4 and 5 correspond to the cross-sectional view shown in FIG. 2, and the cross-sectional view shown in FIG. 6 corresponds to the cross-sectional view shown in FIG. 3. FIG. 7A is a perspective view showing a process of manufacturing a temporary laminate, FIG. 7B is a perspective view showing a mother laminate, and FIG. 7C is a perspective view showing a plurality of laminate precursors obtained by cutting the mother laminate. FIG. 8A is a side view showing the configuration of an apparatus for forming a side margin portion on the side surface of a laminate precursor, and FIGS. 8B and 8C are side views showing the process of forming a side margin portion on the side surface of a laminate precursor. FIG. 9 is a perspective view showing a main body portion. FIG. 10 is a perspective view showing a mounting structure according to an embodiment of the present disclosure, and FIG. 11 is a cross-sectional view taken along the cutting plane line XI-XI of FIG. 10.

[0012] As shown in FIGS. 1 to 3, the multilayer ceramic capacitor 1 of the present embodiment includes a laminate 2, a first side margin portion 3a, a second side margin portion 3b, a first external electrode 4a, and a second external electrode 4b. Hereinafter, the laminate 2, the first side margin portion 3a, and the second side margin portion 3b may be collectively referred to as the main body portions 2, 3a, 3b. Also, the first side margin portion 3a and the second side margin portion 3b may be collectively referred to as the side margin portions 3a, 3b. Further, the first external electrode 4a and the second external electrode 4b may be collectively referred to as the external electrodes 4a, 4b.

[0013] The laminate 2 has a substantially rectangular parallelepiped shape. The laminate 2 has a first face 7a and a second face 7b facing each other in the third direction, a first end face 8a and a second end face 8b facing each other in the first direction, and a first side face 9a and a second side face 9b facing each other in the second direction. Hereinafter, the first face 7a and the second face 7b may be collectively referred to as main faces 7a and 7b, the first end face 8a and the second end face 8b may be collectively referred to as end faces 8a and 8b, and the first side face 9a and the second side face 9b may be collectively referred to as side faces 9a and 9b. The main faces 7a and 7b may be perpendicular to the third direction, the end faces 8a and 8b may be perpendicular to the first direction, and the side faces 9a and 9b may be perpendicular to the second direction.

[0014] The laminate 2 is composed of alternating layers of dielectric layers 5 and internal electrode layers 6. The dielectric layers 5 and internal electrode layers 6 are stacked in a third direction. The internal electrode layers 6 are exposed on the first side surface 9a and the second side surface 9b. In addition, the internal electrode layers 6 are exposed on either the first end surface 8a or the second end surface 8b, depending on their polarity.

[0015] The dielectric layer 5 is composed of an insulating material. The dielectric layer 5 may be composed of a ceramic material mainly composed of, for example, BaTiO3 (barium titanate), CaTiO3 (calcium titanate), SrTiO3 (strontium titanate), BaZrO3 (barium zirconate), etc. In this specification, "main component" refers to the component with the highest proportion in the material or component of interest. The proportion may be expressed as concentration (mol%).

[0016] The internal electrode layer 6 is made of a conductive material. The internal electrode layer 6 may be made of a metallic material mainly composed of, for example, Ni (nickel), Pd (palladium), Ag (silver), Cu (copper), etc.

[0017] The thinner the dielectric layer 5 is in the third direction, the more the capacitance (hereinafter also simply referred to as capacitance) of the multilayer ceramic capacitor 1 can be increased. The dielectric layer 5 may have a thickness of, for example, 0.1 μm to 10 μm. Furthermore, as long as the characteristics as a capacitor can be ensured, the thinner the internal electrode layer 6 is in the third direction, the more internal defects caused by internal stress can be suppressed, and the reliability of the multilayer ceramic capacitor 1 can be improved. The internal electrode layer 6 may have a thickness of, for example, 1.5 μm or less.

[0018] The ends of the laminate 2 in the third direction may be composed of cover layers. The cover layers are made of an insulating material. The cover layers may be composed of, for example, one or more dielectric layers 5.

[0019] The first side margin portion 3a is located on the first side surface 9a of the laminate 2 and has a first outer surface 3aa on the opposite side from the first side surface 9a. The first side margin portion 3a electrically insulates the internal electrode layers 6 with different polarities that are exposed on the first side surface 9a. In addition, the first side margin portion 3a physically protects the edges of the internal electrode layers 6 that are exposed on the first side surface 9a.

[0020] The second side margin portion 3b is located on the second side surface 9b of the laminate 2 and has a second outer surface 3ba on the opposite side from the second side surface 9b. The second side margin portion 3b electrically insulates the internal electrode layers 6 with different polarities that are exposed on the second side surface 9b. In addition, the second side margin portion 3b physically protects the edges of the internal electrode layers 6 that are exposed on the second side surface 9b. Hereinafter, the components composed of the laminate 2 and the side margin portions 3a and 3b may be referred to as the main body portions 2, 3a and 3b.

[0021] The side margins 3a and 3b are made of an insulating material. The side margins 3a and 3b may also be made of a ceramic material. This configuration allows the side margins 3a and 3b to have insulating properties and relatively high mechanical strength. Furthermore, if the side margins 3a and 3b are made of a ceramic material, it becomes possible to fire the laminate 2 and the side margins 3a and 3b simultaneously. The side margins 3a and 3b may be made of a ceramic material mainly composed of, for example, BaTiO3, CaTiO3, SrTiO3, BaZrO3, etc. In Figure 1, the boundary between the laminate 2 and the side margins 3a and 3b is shown by a dashed line, but the actual boundary is not clearly visible.

[0022] The thinner the thickness of the side margin portions 3a and 3b in the second direction, the smaller and larger the multilayer ceramic capacitor 1 can be. The first side margin portion 3a and the second side margin portion 3b may each have a thickness of, for example, about 30 μm or less.

[0023] The first external electrode 4a is located from the first end face 8a to the first surface 7a, the second surface 7b, the first outer surface 3aa, and the second outer surface 3ba. The first external electrode 4a is electrically connected to the internal electrode layer 6 exposed on the first end face 8a. The second external electrode 4b is located from the second end face 8b to the first surface 7a, the second surface 7b, the first outer surface 3aa, and the second outer surface 3ba. The second external electrode 4b is electrically connected to the internal electrode layer 6 exposed on the second end face 8b.

[0024] The first external electrode 4a and the second external electrode 4b each have a first portion 41 and a second portion 42. The first portion 41 is located on the first surface 7a and covers the portion of the first surface 7a near the first end surface 8a and the portion of the first surface 7a near the second end surface 8b. The first portion 41 has a first electrode surface 41a on the side opposite to the first surface 7a. The second portion 42 is located on the first outer surface 3aa and covers the portion of the first outer surface 3aa near the first end surface 8a and the portion of the first outer surface 3aa near the second end surface 8b. The second portion 42 has a second electrode surface 42a on the side opposite to the first outer surface 3aa. The first outer surface 3aa has a covered area 3ab covered by the second portion 42 and an exposed area 3ac exposed from the second portion 42.

[0025] The external electrodes 4a and 4b are composed of one or more conductive layers. As shown in Figures 2 and 3, the external electrodes 4a and 4b may be composed of a first layer 43 and a second layer 44. The first layer 43 is also called the base layer. The second layer 44 is also called the outer layer. The base layer 43 is in direct contact with the main body portions 2, 3a, and 3b and is connected to the ends of the internal electrode layer 6 that are exposed on the end faces 8a and 8b. The outer layer 44 covers the side of the base layer 43 opposite to the laminate 2 side. By composing the external electrodes 4a and 4b with multiple conductive layers, the adhesion between the external electrodes 4a and 4b and the main body portions 2, 3a, and 3b can be improved. Furthermore, the wettability of the external electrodes 4a and 4b to the conductive bonding material used when mounting the multilayer ceramic capacitor 1 to a substrate can be improved. As a result, the reliability of the multilayer ceramic capacitor 1 and the mounting structure including the multilayer ceramic capacitor 1 can be improved.

[0026] The base layer 43 is composed of a metallic material. Examples of metallic materials used for the base layer 43 include metals such as Ni, Cu, Ag, Pd, and Au, or alloys made of these metals. The base layer 43 may be formed using thin-film formation techniques such as plating, sputtering, or vapor deposition, or it may be formed using thick-film formation techniques such as dip lithography, screen printing, or gravure printing.

[0027] The outer layer 44 is made of a metallic material. Examples of metallic materials used for the outer layer 44 include metals such as Ni, Cu, Au, and Sn. The outer layer 44 may be formed using thin-film formation techniques such as electroless plating or electrolytic plating.

[0028] As shown in Figures 2 and 3, the multilayer ceramic capacitor 1 has a configuration in which the distance s1 between the second electrode surface 42a and the exposed area 3ac in a direction perpendicular to the first side surface 9a is smaller than the distance s2 between the first electrode surface 41a and the first surface 7a in a direction perpendicular to the first surface 7a. With this configuration, when mounting the multilayer ceramic capacitor 1 on the substrate 10, mounting it so that the first side surface 9a faces the mounting surface 10a of the substrate 10 (see Figures 10 and 11) allows for a smaller distance between the multilayer ceramic capacitor 1 and the mounting surface 10a compared to mounting it so that the first surface 7a faces the mounting surface 10a. As a result, when the multilayer ceramic capacitor 1 is driven, the multilayer ceramic capacitor 1 and the substrate 10 can be substantially in surface contact, suppressing the deflection of the substrate 10. Consequently, vibration of the substrate 10 due to the deflection of the substrate 10 can be reduced, and noise from the substrate 10 can be reduced. In this specification, the distance between the multilayer ceramic capacitor 1 and the mounting surface 10a refers to the distance between the parts of the main body 2, 3a, 3b that are not covered by the external electrodes 4a, 4b and the mounting surface 10a. Furthermore, if the distance between the second electrode surface 42a and the exposed area 3ac is not constant, the average value of the distance between the second electrode surface 42a and the exposed area 3ac may be used as the distance s1. Also, if the distance between the first electrode surface 41a and the first surface 7a is not constant, the average value of the distance between the first electrode surface 41a and the first surface 7a may be used as the distance s2.

[0029] The multilayer ceramic capacitor 1 may have a configuration in which the second electrode surface 42a and the exposed area 3ac are flush. With this configuration, when mounting the multilayer ceramic capacitor 1 on the substrate 10, the gap between the multilayer ceramic capacitor 1 and the mounting surface 10a can be substantially eliminated by mounting it so that the first side surface 9a faces the mounting surface 10a. As a result, the deflection of the substrate 10 when the multilayer ceramic capacitor 1 is driven can be effectively reduced, and the noise of the substrate 10 can be effectively reduced.

[0030] In the multilayer ceramic capacitor 1, the difference between the spacing s1 and the spacing s2 results in different visibility when viewed from the first surface 7a side and when viewed from the first outer surface 3aa side, making it easy to distinguish the first outer surface 3aa. As a result, when mounting the multilayer ceramic capacitor 1 on the substrate 10, it becomes easy to mount it with the first surface 9a facing the mounting surface 10a.

[0031] In the multilayer ceramic capacitor 1 of this disclosure, the second side margin portion 3b may be configured in the same way as the first side margin portion 3a, and the portion of the external electrodes 4a and 4b located on the second outer surface 3ba may be configured in the same way as the second portion 42 of the external electrodes 4a and 4b. Furthermore, the second surface 7b may be configured in the same way as the first surface 7a, and the portion of the external electrodes 4a and 4b located on the second surface 7b may be configured in the same way as the first portion 41 of the external electrodes 4a and 4b.

[0032] Next, another example of the multilayer ceramic capacitor 1 of this disclosure will be described.

[0033] As shown in Figure 4, the multilayer ceramic capacitor 1 may have a configuration in which the distance s3 between the exposed area 3ac of the first outer surface 3aa and the first surface 9a (also called the central side margin) is larger than the distance s4 between the covered area 3ab of the first outer surface 3aa and the first surface 9a (also called the end face side margin). A relatively large central side margin s3 increases the mechanical strength of the first outer surface 3aa side of the main body parts 2, 3a, and 3b. As a result, even if the exposed area 3ac is subjected to impact when mounting the multilayer ceramic capacitor 1 on the substrate 10, the occurrence of cracks originating from the exposed area 3ac can be reduced, thereby improving the reliability of the multilayer ceramic capacitor 1. The size of the central side margin s3 may be, for example, about 30 μm or less. Furthermore, even if it is necessary to secure a central side margin s3 of a predetermined size for a multilayer ceramic capacitor 1 of predetermined dimensions, a large area of ​​the internal electrode layer 6 can be secured when viewed along the third direction. As a result, it becomes possible to provide a small and high-capacity multilayer ceramic capacitor 1. If the distance between the exposed region 3ac and the first side surface 9a is not constant, the average value of the distance between the exposed region 3ac and the first side surface 9a may be used as interval s3. Also, if the distance between the covered region 3ab and the first side surface 9a is not constant, the average value of the distance between the covered region 3ab and the first side surface 9a may be used as interval s4.

[0034] The end face side margin s4 should be of a size that electrically insulates the internal electrode layer 6 connected to the first external electrode 4a and the second external electrode 4b, and electrically insulates the internal electrode layer 6 connected to the second external electrode 4b and the first external electrode 4a. The size of the end face side margin s4 may be about 5% to 80% of the size of the center side margin s3. The size of the end face side margin s4 may be, for example, about 1 μm or more. Since the covered area 3ab is covered by the external electrodes 4a and 4b, even if the end face side margin s4 is relatively small, cracks originating from the covered area 3ab are unlikely to occur.

[0035] As shown in Figure 4, the multilayer ceramic capacitor 1 may have a configuration in which, in a cross-section parallel to the first surface 7a, the first outer surface 3aa has at least two bent portions 3ad, and the first external electrode 4a and the second external electrode 4b each extend to the two bent portions 3ad. This configuration increases the contact area between the external electrodes 4a, 4b and the first side margin portion 3a, thereby increasing the connection strength between the external electrodes 4a, 4b and the main body portions 2, 3a, 3b. As a result, the risk of the external electrodes 4a, 4b peeling off from the main body portions 2, 3a, 3b is reduced, thus improving the reliability of the multilayer ceramic capacitor 1.

[0036] The first side margin portion 3a may have a thickness in the second direction at each of the two bent portions 3ad, increasing from the end faces 8a, 8b of the main body portions 2, 3a, 3b toward the center in the first direction. This allows the first side margin portion 3a and the external electrodes 4a, 4b to form a recess 22, as shown in Figure 4. As a result, even if a large amount of conductive bonding material 12 flows between the multilayer ceramic capacitor 1 and the substrate 10 when mounting the multilayer ceramic capacitor 1 to the substrate 10, the excess conductive bonding material 12 accumulates in the recess 22, making it less likely for it to flow toward the center in the first direction of the multilayer ceramic capacitor 1 (see Figures 10 and 11). Consequently, the risk of electrical short circuits between the first external electrode 4a and the second external electrode 4b can be reduced, thereby improving the reliability of the mounting structure including the multilayer ceramic capacitor 1.

[0037] As shown in Figures 5 and 6, the multilayer ceramic capacitor 1 may have a configuration in which the distance s5 between the second electrode surface 42a and the exposed area 3ac in a direction perpendicular to the first side surface 9a is smaller than the distance s6 between the first electrode surface 41a and the first surface 7a in a direction perpendicular to the first surface 7a. In other words, the multilayer ceramic capacitor 1 may have a configuration in which the thickness of the second portion 42 of the external electrodes 4a and 4b is thinner than the thickness of the first portion 41 of the external electrodes 4a and 4b. With this configuration, when mounting the multilayer ceramic capacitor 1 on the substrate 10, by mounting it so that the first side surface 9a faces the mounting surface 10a of the substrate 10 (see Figures 10 and 11), the distance between the substrate electrodes 11a and 11b to which the external electrodes 4a and 4b are electrically connected and the internal electrode layer 6 can be shortened. As a result, the equivalent series inductance of the mounting structure including the multilayer ceramic capacitor 1 can be reduced. Ultimately, this reduces the noise of the substrate 10 and provides a multilayer ceramic capacitor 1 that can be used in the high-frequency range. If the distance between the second electrode surface 42a and the exposed area 3ac is not constant, the average value of the distance between the second electrode surface 42a and the exposed area 3ac may be used as interval s5. Also, if the distance between the first electrode surface 41a and the first surface 7a is not constant, the average value of the distance between the first electrode surface 41a and the first surface 7a may be used as interval s6.

[0038] By making the thickness of the second portion 42 thinner than the thickness of the first portion 41, the spacing s1 can be made smaller than the spacing s2 even when the thickness of the first side margin portion 3a is constant (see Figures 2 and 3). Therefore, the process of forming the side margin portions 3a and 3b in the manufacturing of the multilayer ceramic capacitor 1 can be simplified.

[0039] Next, an example of a manufacturing method for the multilayer ceramic capacitor 1 will be described.

[0040] First, a powder mainly composed of dielectric materials such as BaTiO3, CaTiO3, SrTiO3, or mixtures thereof is prepared as the material for the dielectric layer 5, and an organic vehicle is added to the powder to prepare a ceramic slurry. Next, a ceramic green sheet (hereinafter also simply called a green sheet) 13 is fabricated using a sheet forming method such as the doctor blade method or the die coater method. The thickness of the green sheet 13 may be, for example, about 0.5 to 10 μm.

[0041] Next, a conductive paste is prepared using a powder mainly composed of metal materials such as Ni, Cu, Ag, or mixtures thereof as the material for the internal electrode layer 6. Subsequently, a pattern sheet 14, on which the electrode pattern that will form the internal electrode layer is printed, is formed on the main surface of the green sheet 13 using the prepared conductive paste. For printing the electrode pattern, printing methods such as screen printing or gravure printing can be used.

[0042] Next, a temporary laminate is created by stacking a predetermined number of pattern sheets 14 on top of a predetermined number of stacked green sheets 13, and then stacking a predetermined number of green sheets 13 (see Figure 7A). Next, the temporary laminate is pressed in the stacking direction to obtain a base laminate 15 (see Figure 7B). The temporary laminate can be pressed using, for example, a hydrostatic press. The base laminate 15 is cut along a virtual dividing line 16 to create a laminate precursor 2p that will become the laminate 2 (see Figure 7C). The base laminate 15 can be cut using, for example, a push-cutting machine or a dicing saw. Since the laminate precursor 2p has the same structure as the laminate 2, the terms and reference numerals such as main faces 7a, 7b, end faces 8a, 8b, and side faces 9a, 9b will also be used for the laminate precursor 2p below.

[0043] Next, ceramic green sheets that will become side margins 3a and 3b are formed on the sides 9a and 9b of the laminate precursor 2p. Figure 8A shows an example of the configuration of an apparatus for forming green sheets that will become side margins 3a and 3b on the sides 9a and 9b. The laminate precursor 2p has its second side 9b fixed to the lower surface of the first base 18a via an adhesive and peelable support sheet 17. Below the laminate precursor 2p fixed to the first base 18a, the second base 18b is positioned. The first base 18a and the second base 18b are positioned such that the lower surface of the first base 18a and the upper surface of the second base 18b are substantially parallel. Multiple strip-shaped members 19 are positioned on the upper surface of the second base 18b. The multiple strip-shaped members 19 are positioned to extend in a direction perpendicular to the first surface 7a of the laminate precursor 2p. The spacing between adjacent strip-shaped members 19 is shorter than the length of the laminate precursor 2p (the distance between the first end face 8a and the second end face 8b). Above the second base 18b, a resin sheet 20 made of an elastic material is arranged to cover the multiple strip-shaped members 19. A green sheet 21, which forms the first side margin portion 3a, is placed on the upper surface of the resin sheet 20.

[0044] First, as shown in Figure 8B, the first base 18a is moved downward and the laminate precursor 2p is pressed against the green sheet 21, thereby pressing the green sheet 21 against the first side surface 9a. At this time, the laminate precursor 2p is pressed with a pressing force such that the resin sheet 20 deforms according to the shape of the stripe-shaped step formed by the second base 18b and the multiple strip-shaped members. This makes it possible to make the green sheet 21 pressed against the first side surface 9a such that the thickness on the central side in the longitudinal direction (left-right direction in Figure 9B) is greater than the thickness on the end face side.

[0045] Next, as shown in Figure 8C, with the green sheet 21 pressed against the first side surface 9a of the laminate precursor 2p, the first base 18a is moved upward. Since the portion of the green sheet 21 that is not in contact with the first side surface 9a remains on the resin sheet 20, the green sheet 21 that will become the first side margin portion 3a can be formed on the first side surface 9a. Similarly, the green sheet 21 that will become the second side margin portion 3b can be formed on the second side surface 9b, and the main body precursors that will become the main body portions 2, 3a, and 3b can be manufactured.

[0046] Next, the main body precursor is degreased in an air atmosphere, an inert gas atmosphere, or a reducing atmosphere at atmospheric pressure or reduced pressure, and then fired in a reducing atmosphere. The firing temperature may be, for example, around 1100°C to 1300°C. Subsequently, the fired main body precursor is re-oxidized in a nitrogen atmosphere. The re-oxidized main body precursor is placed in a pot containing polishing powder, polishing media, etc., and rotated to polish it, thereby removing the corners and burrs of the main body precursor and obtaining the main body parts 2, 3a, and 3b as shown in Figure 9. By forming external electrodes 4a and 4b on the obtained main body parts 2, 3a, and 3b, a multilayer ceramic capacitor 1 can be manufactured.

[0047] As mentioned above, the multilayer ceramic capacitor 1 may have a configuration in which the thickness of the second portion 42 of the external electrodes 4a and 4b is thinner than the thickness of the first portion 41 of the external electrodes 4a and 4b (see Figures 5 and 6). Such a multilayer ceramic capacitor 1 can be manufactured as follows.

[0048] First, the main body parts 2, 3a, and 3b are manufactured in the same manner as described above. Note that the side margin parts 3a and 3b may have a central side margin s3 that is larger than the end face side margin s4 (see Figure 4), or the central side margin s3 and the end face side margin s4 may be the same size. In other words, when forming the ceramic green sheets 21 that will become the side margin parts 3a and 3b on the sides 9a and 9b, the apparatus with the configuration shown in Figure 9A may be used, or an apparatus in which multiple strip-shaped members 19 are not arranged and the ceramic green sheets 21 are arranged on the upper surface of the second base 18b via a resin sheet 20 may be used.

[0049] Next, a conductive paste to form the base layer 43 is prepared, and the prepared conductive paste is applied to the parts of the main body parts 2, 3a, and 3b near the first end face 8a and near the second end face 8b with a constant thickness. Subsequently, the conductive paste applied to the first outer surface 3aa is subjected to blotting. Blotting is a process in which a portion of the conductive paste applied to the first outer surface 3aa is removed (wiped off) by pressing the conductive paste applied to the first outer surface 3aa onto a plate and then pulling it away. After firing the main body parts 2, 3a, and 3b to which the conductive paste has been applied to form the base layer 43, an outer layer 44 is formed, thereby creating external electrodes 4a and 4b in which the thickness of the second part 42 is thinner than the thickness of the first part 41.

[0050] Next, we will describe the implementation structure of this disclosure.

[0051] As shown in Figures 10 and 11, the mounting structure 100 of this embodiment comprises a multilayer ceramic capacitor 1 and a substrate 10. The substrate 10 has a mounting surface 10a. A first substrate electrode 11a and a second substrate electrode 11b are located on the mounting surface 10a. The first substrate electrode 11a and the second substrate electrode 11b are electrically connected to a first external electrode 4a and a second external electrode 4b, respectively. An electrical circuit electrically connected to the multilayer ceramic capacitor 1 may also be located on the mounting surface 10a.

[0052] The multilayer ceramic capacitor 1 is mounted on the mounting surface 10a such that its first side surface 9a faces the mounting surface 10a. The first external electrode 4a and the second external electrode 4b are bonded to the first substrate electrode 11a and the second substrate electrode 11b, respectively, via a conductive bonding material 12. Solder, brazing material, etc. can be used as the conductive bonding material 12.

[0053] Because the mounting structure 100 has a small gap between the multilayer ceramic capacitor 1 and the mounting surface 10a, it can reduce the noise of the substrate 10 when the multilayer ceramic capacitor 1 is driven.

[0054] Although embodiments of this disclosure have been described in detail above, this disclosure is not limited to the embodiments described above, and various modifications and improvements are possible without departing from the gist of this disclosure.

[0055] The multilayer ceramic capacitor and mounting structure of this disclosure can be implemented in the following configurations (1) to (6).

[0056] (1) A substantially rectangular parallelepiped laminate in which dielectric layers and internal electrode layers are alternately stacked, the laminate having a first and second surface facing each other, a first and second side surface facing each other, and a first and second end surface facing each other, A first side margin portion located on the first side surface and having a first outer surface opposite to the first side surface, A second side margin portion located on the second side and having a second outer surface opposite to the second side, A first external electrode is located extending from the first end face to the first surface, the second surface, the first outer surface, and the second outer surface, The present invention includes a second external electrode located from the second end face to the first face, the second face, the first outer surface, and the second outer surface, The first external electrode and the second external electrode are connected to different internal electrode layers of the internal electrode layer, The first external electrode and the second external electrode each have a first portion located on the first surface and a second portion located on the first outer surface, The first portion of the series has a first electrode surface opposite to the first surface side, The second portion has a second electrode surface opposite to the first outer surface side, The first outer surface has a covered area covered by the second portion and an exposed area not covered by the second portion. A multilayer ceramic capacitor in which the distance between the second electrode surface and the exposed area in a direction perpendicular to the first side surface is smaller than the distance between the first electrode surface and the first surface in a direction perpendicular to the first surface.

[0057] (2) The multilayer ceramic capacitor according to (1) above, wherein the first side surface is positioned to face the substrate when the multilayer ceramic capacitor is mounted on the substrate.

[0058] (3) The multilayer ceramic capacitor according to (1) or (2) above, wherein, in a direction perpendicular to the first side surface, the distance between the exposed area and the first side surface is greater than the distance between the covered area and the first side surface.

[0059] (4) The multilayer ceramic capacitor according to (3) above, wherein the first outer surface has two bent portions, and the first external electrode and the second external electrode each extend to the two bent portions.

[0060] (5) A multilayer ceramic capacitor according to any one of (1) to (4) above, wherein the distance between the second electrode surface and the covering region in a direction perpendicular to the first side surface is smaller than the distance between the first electrode surface and the first surface in a direction perpendicular to the first surface.

[0061] (6) A multilayer ceramic capacitor as described in any of (1) to (5) above, A substrate having a mounting surface, The multilayer ceramic capacitor is mounted on the substrate such that the first side surface faces the mounting surface, forming a mounting structure. [Explanation of symbols]

[0062] 1. Multilayer ceramic capacitor 2 Laminate 2p laminate precursor 3a First side margin section 3a Side margin section 3aa 1st outer surface 3ab coverage area 3ac exposed area 3ad bend 3b Second side margin section 3ba 2nd outer surface 4a 1st external electrode 4b 2nd external electrode 41 Part 1 41a 1st electrode surface 42 Part 2 42a 2nd electrode surface 43 1st layer (base layer) 44 2nd layer (outer layer) 5. Dielectric layer 6 Internal electrode layer 7a 1st page 7b 2nd side 8a 1st end face 8b 2nd end face 9a 1st side 9b Second side 10 circuit boards 10a Mounting surface 11a 1st substrate electrode 11b 2nd substrate electrode 12 Conductive bonding material 13 Ceramic Green Sheet 14 Pattern Sheets 15 Mother laminate 16 virtual partition lines 17 Support Sheet 18a First Pedestal 18b Second Pedestal 19 Strip-shaped member 20 resin sheets 21 Ceramic Green Sheet 22 recess 100 Implementation Structures

Claims

1. A substantially rectangular parallelepiped laminate in which dielectric layers and internal electrode layers are alternately stacked, the laminate having a first and second surface facing each other, a first and second side surface facing each other, and a first and second end surface facing each other, A first side margin portion located on the first side surface and having a first outer surface opposite to the first side surface, A second side margin portion located on the second side surface and having a second outer surface opposite to the second side surface, A first external electrode located from the first end face to the first surface, the second surface, the first outer surface, and the second outer surface, The second external electrode is located extending from the second end face to the first face, the second face, the first outer surface, and the second outer surface, The first external electrode and the second external electrode are connected to different internal electrode layers of the internal electrode layer, The first external electrode and the second external electrode each have a first portion located on the first surface and a second portion located on the first outer surface, The first part of the above has a first electrode surface opposite to the first surface side, The second portion has a second electrode surface opposite to the first outer surface side, The first outer surface has a covered area covered by the second portion and an exposed area not covered by the second portion. A multilayer ceramic capacitor in which the distance between the second electrode surface and the exposed region in a direction perpendicular to the first side surface is smaller than the distance between the first electrode surface and the first surface in a direction perpendicular to the first surface, The first side surface is a multilayer ceramic capacitor positioned to face the substrate when the multilayer ceramic capacitor is mounted on the substrate.

2. The multilayer ceramic capacitor according to claim 1, wherein, in a direction perpendicular to the first side surface, the distance between the exposed area and the first side surface is greater than the distance between the covered area and the first side surface.

3. The multilayer ceramic capacitor according to claim 2, wherein the first outer surface has two bent portions, and the first external electrode and the second external electrode each extend to the two bent portions.

4. The multilayer ceramic capacitor according to claim 1 or 2, wherein the distance between the second electrode surface and the covering region in a direction perpendicular to the first side surface is smaller than the distance between the first electrode surface and the first surface in a direction perpendicular to the first surface.

5. A multilayer ceramic capacitor according to claim 1, A substrate having a mounting surface, The multilayer ceramic capacitor is mounted on the substrate such that the first side surface faces the mounting surface, forming a mounting structure.

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