Mounting structure for electronic component

Abstract

Provided is a mounting structure for an electronic component, the structure being capable of suppressing occurrence of cracks in the electronic component.　A mounting structure 1 comprises: a pair of lands 30 disposed on a substrate 20 so as to be apart from each other; a solder 40 disposed on each of the lands 30; and a multilayer ceramic capacitor 10 that has a component body 11 and a pair of external electrodes 16, each of the external electrodes 16 being connected to the land 30 via the solder 40. Each of the external electrodes 16 includes an extension part 16c that covers a main surface 17a and a side surface of the component body 11. When a direction orthogonal to the surface of the substrate 20 is defined as the Z-direction, the dimension in the Z-direction of the solder 40 disposed in a region sandwiched between the land 30 and the extension part 16c is 1-100 μm.

Description

Mounting structure for electronic components

[0001] The present invention relates to a mounting structure for electronic components.

[0002] Conventionally, two-terminal electronic components such as multilayer ceramic capacitors and inductors have been mounted on a circuit board by soldering. Patent Document 1 discloses a mounting structure in which a pair of external electrodes provided at both ends of a multilayer ceramic capacitor in the longitudinal direction are connected to a pair of electrode pads provided on the board by soldering.

[0003] JP 2014-086606 A

[0004] When the ambient temperature changes during use of electronic devices, stress occurs in the electronic components due to differences in the linear expansion coefficients of the electronic components, solder, and substrate. Stress in electronic components can cause cracks to form at the interface between the element body and the external electrodes. Furthermore, if electronic components with such cracks are exposed to a humidity-resistant environment, the internal insulation resistance decreases, generating heat and potentially damaging the electronic device.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a mounting structure for electronic components that can suppress the occurrence of cracks in electronic components.

[0006] In order to solve the above-mentioned problems, the mounting structure of an electronic component of the present invention comprises: a pair of lands arranged spaced apart on a substrate; solder arranged on each of the lands; a component body having laminated dielectric layers and internal electrode layers, the component body including a pair of main surfaces facing each other in a stacking direction, a pair of side surfaces facing each other in a width direction perpendicular to the stacking direction, and a pair of end surfaces facing each other in a length direction perpendicular to the stacking direction and the width direction; and a pair of external electrodes arranged on each of the end surfaces, each of the external electrodes being connected to a corresponding land via the solder, wherein each of the external electrodes includes an extension portion extending to at least a portion of each of the main surfaces and each of the side surfaces, and wherein, when the direction perpendicular to the surface of the substrate is defined as the Z direction, the dimension of the solder arranged in the region between the land and the extension portion in the Z direction is 1 μm or more and 100 μm or less.

[0007] According to the present invention, it is possible to provide a mounting structure for electronic components that can suppress the occurrence of cracks in electronic components.

[0008] Fig. 1 is a perspective view showing a multilayer ceramic capacitor as an electronic component applied to the electronic component mounting structure according to the first embodiment. Fig. 2 is a plan view showing the electronic component mounting structure according to the first embodiment. Fig. 3 is a cross-sectional view taken along line III-III in Fig. 2. Fig. 4 is an enlarged cross-sectional view showing a main portion of the electronic component mounting structure according to the first embodiment. Fig. 5 is a plan view showing the electronic component mounting structure according to a second embodiment. Fig. 6 is a cross-sectional view taken along line VI-VI in Fig. 5.

[0009] Hereinafter, embodiments will be described with reference to the drawings. (First Embodiment) Fig. 1 shows a multilayer ceramic capacitor 10 as an electronic component applied to a mounting structure for an electronic component according to a first embodiment. The first embodiment is one form of a structure in which the multilayer ceramic capacitor 10 is mounted on a substrate.

[0010] The multilayer ceramic capacitor 10 has a generally rectangular parallelepiped shape as a whole and includes a component body 11 and a pair of external electrodes 16. The component body 11 has an internal layer portion 12 configured by alternately stacking a plurality of dielectric layers 121 and internal electrode layers 122.

[0011] In this specification, the direction in which the dielectric layers 121 and the internal electrode layers 122 are stacked is referred to as the "stacking direction T." The direction perpendicular to the stacking direction T is referred to as the "length direction L." The direction perpendicular to the stacking direction T and the length direction L is referred to as the "width direction W." The pair of external electrodes 16 are aligned in the length direction L.

[0012] The dimensions of the multilayer ceramic capacitor 10 include, for example, dimensions of 0.2 mm or more and 1.7 mm or less in the length direction L, 0.12 mm or more and 0.9 mm or less in the width direction W, and 0.12 mm or more and 0.9 mm or less in the stacking direction T, but are not limited to these.

[0013] The component body 11 has a substantially rectangular parallelepiped shape and includes a pair of main surfaces 17 a facing each other in the stacking direction T, a pair of side surfaces 17 b facing each other in the width direction W, and a pair of end surfaces 17 c facing each other in the length direction L.

[0014] The component body 11 has an inner layer portion 12 therein. The inner layer portion 12 has a multilayer structure in which a plurality of internal electrode layers 122 and a plurality of dielectric layers 121 are alternately stacked in a stacking direction T. The four surfaces of the inner layer portion 12, on both sides in the width direction W and on both sides in the stacking direction T, are covered with outer dielectric ceramic layers 13 made of the same material as the dielectric ceramic layers.

[0015] The internal electrode layer 122 is formed of a metal material such as Ni, Cu, Ag, Pd, Ag-Pd alloy, Au, etc., but is not limited to these metal materials and may be formed of other conductive materials.

[0016] The dielectric layer 121 and the outer dielectric ceramic layer 13 are made of, for example, a ceramic material containing barium titanate as a main component or other ceramic material with a high dielectric constant (for example, CaTiO ３ , SrTiO ３ , CaZrO ３ It is formed by firing a material containing, for example, tungsten, tungsten oxide, tungsten carbide ...

[0017] A pair of external electrodes 16 are respectively arranged at both ends of the component body 11 in the longitudinal direction L. Each external electrode 16 covers a pair of end faces 17c of the component body 11. Note that each of the pair of external electrodes 16 may also be arranged on a portion of the pair of main surfaces 17a or a portion of the pair of side surfaces 17b. In the multiple internal electrode layers 122 in the inner layer portion 12, one side of the internal electrode layers adjacent in the stacking direction T is connected to one external electrode 16, and the other side is connected to the other external electrode. Each of the pair of external electrodes 16 has an end face 16a in the longitudinal direction L.

[0018] The external electrodes 16 are formed, for example, by a laminated film of a sintered metal layer and a plating layer. The sintered metal layer is formed by baking a paste of, for example, Cu, Ni, Ag, Pd, an Ag-Pd alloy, Au, etc. The plating layer is formed, for example, by a Ni plating layer covered with a Sn plating layer.

[0019] The multilayer ceramic capacitor 10 is manufactured, for example, by firing the component body 11 and then forming a pair of external electrodes 16 by baking, plating, etc. In some cases, a portion of the external electrodes 16 is fired simultaneously with the component body 11, and then a plating layer of the external electrodes 16 is formed.

[0020] 2 to 4, the mounting structure 1 includes a substrate 20, a pair of lands 30 spaced apart from each other on the substrate 20, solder 40 disposed on each of the lands 30, and a multilayer ceramic capacitor 10. The multilayer ceramic capacitor 10 is mounted on the substrate 20 by soldering.

[0021] The substrate 20 is formed in a sheet shape from an insulating material such as resin, glass, glass epoxy, paper phenol, or ceramics.

[0022] Wiring 33 is formed on the surface 20a of the substrate 20. The wiring 33 is discontinuous with a separation portion 21 sandwiched therebetween, and a pair of lands 30, which are part of the wiring 33 and connected to the external electrodes 16, are exposed on both sides of the separation portion 21. The pair of lands 30 are arranged spaced apart from each other on the surface 20a of the substrate 20. Therefore, the separation portion 21 can also be said to be the region between the pair of lands 30. The pair of lands 30 are arranged side by side so that their positions are the same in a direction perpendicular to the direction in which the lands 30 are arranged.

[0023] The wiring 33 including the lands 30 is formed by depositing a highly conductive metal such as Cu or Ag on the surface 20a of the substrate 20. Each of the pair of lands 30 has a rectangular shape in a plan view and has approximately the same shape and dimensions as each other.

[0024] In this specification, the direction perpendicular to the surface 20a of the substrate 20 is referred to as the "Z direction." The direction perpendicular to the Z direction and in which a pair of lands 30 are aligned is referred to as the "X direction." The direction perpendicular to the X direction and the Z direction is referred to as the "Y direction." Within the X direction, the direction in which the pair of lands 30 are spaced apart is referred to as the "separating direction," and the direction in which the pair of lands 30 face each other is referred to as the "facing direction." Furthermore, "land thickness" refers to the dimension of the land 30 in the Z direction.

[0025] The peripheral edges of the pair of lands 30 in the X and Y directions are referred to as "peripheral edges 31." The edge of the peripheral edges 31 on the separation portion 21 side is referred to as "inner edges 31a." The inner edges 31a are linear and extend in the Y direction.

[0026] The surface 20a of the substrate 20 is covered with an insulating film 22. The insulating film 22 is made of an insulating material, such as solder resist. However, the insulating material is not limited to this, and an insulating coating material for substrates containing a resin as a main component, such as polyolefin resin, acrylic resin, or polyurethane resin, can be suitably used as the insulating material for the insulating film 22. The insulating film 22 extends onto each of the lands 30, and a portion of each land 30 near its peripheral edge 31 is covered with the insulating film 22. The peripheral edge 31 of each land 30 is covered with the insulating film 22. In the separation portion 21, the surface 20a of the substrate 20 is covered with the insulating film 22. In FIG. 2, the portion where the insulating film 22 is disposed is indicated by dot hatching.

[0027] Note that the portion of the insulating film 22 that is arranged on the surface of each land 30 is referred to as the "insulating film 22a," and the portion that is arranged in the region that overlaps with the separation portion 21 as viewed in the Z direction is referred to as the "insulating film 22b." Note that the insulating film 22 that is arranged in the separation portion 21 is included in the insulating film 22b. If the inner edge 31a of the land 30 forms an inclined surface that slopes toward the substrate 20 as it approaches the facing direction, the insulating film 22 that is arranged in the region that overlaps with the inclined surface as viewed in the Z direction is included in the insulating film 22b, but is not included in the insulating film 22a. In this specification, the "thickness of the insulating film 22" means the dimension of the insulating film 22 in the Z direction.

[0028] The multilayer ceramic capacitor 10 mounted on the substrate 20 has a length direction L that is approximately aligned with the X direction, a width direction W that is approximately aligned with the Y direction, and a stacking direction T that is approximately aligned with the Z direction. This causes one main surface 17a of the component body 11 to face substantially parallel to the surface 20a of the substrate 20. Note that the multilayer ceramic capacitor 10 does not necessarily have to be mounted on the substrate 20 with the main surface 17a facing the substrate 20, and may be mounted on the substrate 20 with one side surface 17b facing the substrate 20.

[0029] In the multilayer ceramic capacitor 10, one external electrode 16 is connected to one land 30 via solder 40, and the other external electrode 16 is connected to the other land 30 via solder 40. The end faces 16a of each external electrode 16 are almost all covered with solder 40. Note that the end faces 16a of each external electrode 16 may be partially covered with solder 40. The multilayer ceramic capacitor 10 is arranged so that its center in the width direction W substantially coincides with the center of each land 30 in the width direction W.

[0030] Each of the pair of external electrodes 16 includes a flat end surface covering portion 16b that covers the end surface 17c of the component body 11, and an extension portion 16c that extends from the end surface covering portion 16b in the opposing direction and is disposed on a portion of the pair of principal surfaces 17a and the pair of side surfaces 17b. The extension portion 16c covers only a portion of each of the principal surfaces 17a and the side surfaces 17b on the side of the end surface 17c. The extension portion 16c has an overall rectangular cylindrical shape. The end of the extension portion 16c on the opposing side forms the boundary portion between the external electrode 16 and the component body 11 (hereinafter referred to as the "boundary portion 15"). Note that the extension portion 16c does not necessarily have to have an overall rectangular cylindrical shape. The extension portion 16c does not need to extend to all of the main surfaces 17a and side surfaces 17b, but only needs to extend to at least one of the main surfaces 17a and side surfaces 17b that faces the substrate 20.

[0031] An extension portion 16c covering one main surface 17a of the component body 11 facing the substrate 20 is connected to the land 30 via solder 40. The end portion (boundary portion 15) of the extension portion 16c on the facing side is located further away from the inner edge 31a of the land 30 connected to the extension portion 16c. Note that the end portion (boundary portion 15) of the extension portion 16c on the facing side may be located further away from the inner edge 31a of the land 30 connected to the extension portion 16c or at approximately the same position as the inner edge 31a. In this case, the insulating film 22a may be located between the extension portion 16c and the land 30, or the insulating film 22a may not be provided.

[0032] The insulating film 22b fills the region between the substrate 20 and the component body 11 without leaving any gaps. The dimension of the insulating film 22 in the Z direction is the same as the distance between the substrate 20 and the component body 11. The insulating film 22b supports the component body 11 on the substrate 20. The insulating film 22b corresponds to a support member (more specifically, a first support member). The insulating film 22b may be provided so as to partially fill the region between the substrate 20 and the component body 11. In other words, the region between the substrate 20 and the component body 11 may have a region where the insulating film 22 is not present. In this case, the insulating film 22a can also support the component body 11 on the land 30.

[0033] The insulating film 22a is continuous with the insulating film 22b and extends from the insulating film 22b in the separation direction. The dimension of the insulating film 22a in the Z direction is the same as the separation dimension between the component body 11 and the land 30. The surfaces of the insulating films 22a and 22b (the surfaces on the side away from the substrate 20 in the Z direction) are flush with each other. The insulating film 22a supports the component body 11 on the land 30. The insulating film 22a corresponds to a support member (more specifically, a second support member).

[0034] Each end of the insulating film 22a in the separation direction is in contact with the boundary portion 15. The boundary portion 15 is covered with the insulating film 22b. Each end of the insulating film 22b in the separation direction forms an inclined surface, more specifically, an inclined surface that slopes toward the substrate 20 as it approaches the facing direction. Furthermore, the insulating film 22a does not extend beyond the boundary portion 15 in the separation direction. Note that each end of the insulating film 22a in the separation direction does not have to be in contact with the boundary portion 15. For example, the insulating film 22a may not be present around the boundary portion 15 due to a gap or the like. Furthermore, the insulating film 22a may extend beyond the boundary portion 15 in the separation direction.

[0035] The end of the solder 40 in the facing direction is in contact with the insulating film 22a. The end of the solder 40 on the facing side is an inclined surface, more specifically, an inclined surface that slopes away from the substrate 20 as it approaches the facing direction. Since the end of the insulating film 22a in the separating direction is an inclined surface that slopes toward the substrate 20 as it approaches the facing direction, it is possible to prevent the solder 40 from climbing up onto the insulating film 22a. Note that the end of the solder 40 in the facing direction does not have to be in contact with the insulating film 22a. In other words, a gap or the like may be present between the end of the solder 40 in the facing direction and the insulating film 22.

[0036] The entire area between the extension 16c and the land 30 is filled with the solder 40. This allows the external electrode 16 to be firmly joined to the land 30.

[0037] The type of solder 40 is not particularly limited as long as it has properties that are compatible with each external electrode 16 and each land 30, and may be, for example, Sn-Pb based solder, Sn-Ag-Cu based solder, Sn-Cu based solder, Sn-Bi based solder, etc.

[0038] A gap GAP is formed between the land 30 and the extension 16c of the external electrode 16 facing the land 30. The gap GAP can also be said to be the area sandwiched between the extension 16c and the land 30. The entire gap GAP overlaps with the component body 11 when viewed in the Z direction.

[0039] The dimension of the gap GAP in the Z direction corresponds to the thickness of the insulating film 22b between the component body 11 and the substrate 20 and the thickness of the insulating film 22a between the component body 11 and the land 30. In other words, the dimension of the gap GAP in the Z direction can be adjusted by adjusting the thickness of the insulating film 22a and the thickness of the insulating film 22b.

[0040] The solder 40 is disposed in the gap Gap, and more specifically, fills the entire gap Gap without any gaps. Therefore, the Z-direction dimension of the gap Gap is the same as the Z-direction dimension of the solder 40 disposed in the gap Gap. In this specification, the "thickness of the solder" refers to the Z-direction dimension of the solder. The region sandwiched between the extension portion 16c and the land 30 does not need to be filled with solder 40; the solder 40 may be partially present, or the solder 40 may not be present at all. In this case, a gap or an insulating film 22a may be present in place of the solder 40 in the region sandwiched between the extension portion 16c and the land 30.

[0041] Thermal shock or the like may apply stress to the ceramic sintered body near the tip of the external electrode 16. In this case, cracks may occur in the component body 11, starting from the boundary 15 between the edge of the extension 16c of the external electrode 16 and the component body 11.

[0042] Therefore, it is preferable that the thickness of the solder 40 disposed in the region between the extension 16c and the land 30 (i.e., the gap) be 1 μm or more and 100 μm or less. In this case, stress is less likely to be applied to the boundary portion 15, thereby suppressing the occurrence of cracks. In addition to stress caused by thermal shock, stress caused by bending of the substrate 20 is also less likely to act on the boundary portion 15.

[0043] It is believed that the larger the contact area between the extending portion 16c and the solder 40, the more likely stress caused by thermal shock or the like is to be applied to the boundary portion 15. In the mounting structure 1, the contact area between the extending portion 16c and the solder 40 is relatively large. However, by setting the thickness of the solder 40 within the above-mentioned range, stress is less likely to be applied to the boundary portion 15, and therefore the occurrence of cracks can be suppressed.

[0044] The distance in the Z direction between the land 30 and the extension 16c (in other words, the dimension of the gap Gap in the Z direction) is preferably 1 μm or more and 100 μm or less. Since the thickness of the solder 40 is determined according to the dimension of the gap Gap in the Z direction, the thickness of the solder 40 can be adjusted to a suitable range.

[0045] The thickness of the insulating film 22a is preferably adjusted so that the distance between the extension 16c and the land 30 is within a range of 1 μm to 100 μm. In other words, the thickness of the insulating film 22a is preferably within a range such that the dimension obtained by subtracting the thickness of the land 30 and the extension 16c from the thickness of the insulating film 22b is within a range of 1 μm to 100 μm. In this case, the dimension of the gap GAP in the Z direction can be set to a desired dimension, and the thickness of the solder 40 arranged in the gap GAP can also be set to a desired dimension.

[0046] The thickness of the insulating film 22, the thickness of the lands 30, and the thickness of the solder 40 disposed in the gaps Gap are measured, for example, on a cross section obtained by cutting the mounting structure 1 parallel to the X and Z directions so as to pass through the center of the multilayer ceramic capacitor 1 in the Y direction. The thickness value of the solder 40 is determined, for example, by measuring the thickness of the solder 40 at multiple (e.g., three) positions on the cross section that are equally spaced in the X direction, and averaging the obtained values. The same applies to the insulating film 22 and the lands 30.

[0047] Furthermore, as described above, the boundary portion 15 is in contact with the insulating film 22a, which prevents the boundary portion 15 from coming into contact with the solder 40. This reduces the amount of stress applied to the boundary portion 15, thereby preventing cracks from occurring.

[0048] In the first embodiment, the soldering using the solder 40 is performed by, for example, reflow. That is, the multilayer ceramic capacitor 10 can be reflow-mounted on the substrate 20. A method for mounting the multilayer ceramic capacitor 1 will be described below.

[0049] First, prior to soldering, an insulating film 22 is disposed on the substrate 20. The insulating film 22 is disposed, for example, so as to cover a portion of the land 30, including the peripheral edge portion 31. At this time, the thickness of the insulating film 22 is adjusted so that the Z-direction dimension of the gap G is the desired dimension. Next, a paste-like solder material is applied to the area of ​​the land 30 that is not covered by the insulating film 22. Next, the multilayer ceramic capacitor 1 is disposed in a predetermined position on the land 30. The external electrode 16 sinks into the paste-like solder material until the component body 11 abuts against the insulating films 22a and 22b. A gap Gap is formed between the extension portion 16c of the external electrode 16 and the land 30. The gap Gap is filled with solder material. Some of the solder material is pushed out from between the extension portion 16c and the land 30 and wets up onto the end face covering portion 16b of the external electrode 16. In this state, the solder material solidifies, and the external electrodes 16 and the lands 30 are connected by the solder 40 .

[0050] According to the mounting structure 1 according to the first embodiment, the following effects can be obtained.

[0051] According to the above embodiment, the thickness of the solder 40 disposed in the region between the extension 16c and the land 30 is preferably 1 μm or more and 100 μm or less.

[0052] Thermal shock and the like can cause stress to be applied to the ceramic sintered body near the tip of the external electrode 16. In this case, cracks may occur in the component body 11, starting near the boundary 15 between the edge of the extension 16c of the external electrode 16 and the component body 11. However, by setting the thickness of the solder 40 disposed in the gap Gap to a range of 1 μm to 100 μm, stress can be made less likely to be applied to the boundary 15. This can suppress the occurrence of cracks.

[0053] According to the above embodiment, the distance in the Z direction between the land 30 and the extension portion 16c is preferably 1 μm or more and 100 μm or less.

[0054] This allows the thickness of the solder 40 to be adjusted within a suitable range.

[0055] According to the above embodiment, the insulating film 22a is disposed in the region between the component body 11 and the lands 30. The insulating film 22a supports the component body 11 on the lands 30. The insulating film 22b is disposed in the region defined by the region between the pair of lands 30 when viewed in the Z direction. The insulating film 22b supports the component body 11 on the substrate 20.

[0056] By adjusting the Z-direction dimensions of the insulating films 22a and 22b, the Z-direction dimension of the gap Gap and the thickness of the solder 40 placed in the gap Gap can be adjusted to the desired dimensions.

[0057] According to the above embodiment, the thickness of the insulating film 22a is preferably adjusted so that the distance between the extension portion 16c and the land 30 is within a range of 1 μm to 100 μm. The thickness of the insulating film 22b is preferably set so that the distance between the extension portion 16c and the land 30 is within a range of 1 μm to 100 μm, as described above, by subtracting the thickness of the land 30 from the thickness of the insulating film 22b.

[0058] In these cases, the dimension of the gap GAP in the Z direction can be set in the range of 1 μm to 100 μm, and the thickness of the solder 40 disposed in the gap GAP can be set in the range of 1 μm to 100 μm, thereby making it possible to suppress the occurrence of cracks in the electronic component.

[0059] Second Embodiment Next, a second embodiment will be described with reference to FIGS. 5 and 6. The second embodiment is a partial modification of the first embodiment. Therefore, in the reference drawings, components similar to those of the first embodiment are denoted by the same reference numerals, and their description will be omitted. Only the differences will be described. In FIG. 5, the portion where the insulating film 22 is disposed is indicated by dot hatching. In FIG. 6, the internal structure of the multilayer ceramic capacitor 10 is not shown.

[0060] In the mounting structure 2 of the second embodiment, a support member 50 is disposed between a pair of lands 30. The support member 50 is a member that supports the component body 11 on the substrate 20 and corresponds to a first support member. The support member 50 is disposed approximately in the center of the separation portion 21. The support member 50 includes a block member 51 that is shaped like a rectangular parallelepiped as a whole. The block member 51 is formed, for example, from a metal, more specifically, from copper foil. The block member 51 is formed from a material that has a higher melting point than solder. The block member 51 is disposed on the surface 20a of the substrate 20. The block member 51 is adhered to the surface 20a with, for example, an adhesive.

[0061] The material of the block member 51 is not limited to metal. The block member 51 does not need to be made of a single material. For example, the block member 51 may be formed by stacking multiple layers made of different materials.

[0062] The surface of the separation portion 21 is covered with an insulating film 22b made of solder resist. However, in the second embodiment, the insulating film 22b is formed as a thin film and is thinner than in the first embodiment. Therefore, there is a space between the substrate 20 and the component body 11 where no solder resist is arranged. In this way, the insulating film 22b does not necessarily fill the area between the substrate 20 and the component body 11 without any gaps.

[0063] The insulating film 22b covers the surface of the block member 51. Therefore, the support member 50 is configured to include the block member 51 and a resist film portion 52 that covers the surface of the block member 51. Silk may further be applied to the surface of the resist film portion 52. Note that the block member 51 does not necessarily have to be covered with the insulating film 22, and the resist film portion 52 is not an essential component of the support member 50.

[0064] The support member 50 is tightly sandwiched between the component body 11 and the substrate 20. The Z-direction dimension of the support member 50 is greater than the thickness of the land 30. In the second embodiment, the insulating film 22 is not disposed between the land 30 and the extension 16c. Therefore, the separation distance between the component body 11 and the substrate 20 is the same as the Z-direction dimension of the support member 50. A gap GAP is formed between the component body 11 and the land 30. The Z-direction dimension of the gap GAP is the same as the Z-direction dimension of the support member 50 minus the thickness of the land 30. Therefore, the Z-direction dimension of the gap GAP can be adjusted by adjusting the Z-direction dimension of the support member 50. The thickness of the solder 40 disposed in the gap GAP can then be adjusted.

[0065] The dimension in the Z direction of the support member 50 disposed in the separation portion 21 is preferably set so that the separation dimension between the extension portion 16c and the land 30 is within a range of 1 μm to 100 μm. In this case, the thickness of the solder 40 disposed in the gap Gap can be set to 1 μm to 100 μm. This can suppress the occurrence of cracks in the multilayer ceramic capacitor 1.

[0066] In the second embodiment, the solder 40 extends to the inner edge 31 a of the land 30 and covers the end of the extension 16 c facing the land 30. Even in this configuration, by setting the thickness of the solder 40 within the above range, it is possible to sufficiently suppress the occurrence of cracks.

[0067] Furthermore, the position where the support member 50 can be placed is not limited to on the separation portion 21. For example, the support member 50 may be placed in the gap Gap, or the block member 51 may be placed on the land 30. In this case, the dimension in the Z direction of the support member 50 placed in the gap Gap is preferably 1 μm or more and 100 μm or less. This allows the thickness of the solder 40 placed in the gap Gap to be within a desired range.

[0068] The present invention is not limited to the above-described embodiment, and modifications and improvements within the scope of achieving the object of the present invention are included in the present invention.

[0069] For example, in the first embodiment, the end of the insulating film 22a in the separation direction extends to a position where it contacts the end of the extending portion 16c in the opposing direction, but the insulating film 22a may extend further in the separation direction than the boundary portion 15. The insulating film 22a may be disposed in the region sandwiched between the extending portion 16c and the land 30, and the region sandwiched between the extending portion 16c and the land 30 does not have to be filled with solder 40 over the entire region. In this case, the distance between the solder 40 and the boundary portion 15 can be increased, thereby more effectively preventing the solder 40 from contacting the boundary portion 15. However, the configuration of the first embodiment is preferable in that it enables the external electrode 16 to be firmly soldered to the land 30.

[0070] The support member 50 is not limited to the configuration of the second embodiment, as long as it can maintain a distance between the extensions 16c of the external electrodes 16 and the substrate 20. The support member may be, for example, an adhesive. In this case, the adhesive may be, for example, an epoxy-based resin adhesive. However, it is preferable that the support member 50 be made of a material with a higher melting point than solder. Furthermore, solder connecting the external electrodes and lands is not considered to be a support member.

[0071] The multilayer ceramic capacitor 10 in the above embodiment is an example of an electronic component, but the electronic component is not limited to this, and other two-terminal electronic components such as inductors are also applicable. For example, in the case of an inductor, the component body is made of magnetic ceramics or the like.

[0072] The present invention also includes the following combinations:

[0073] <1> An electronic component comprising: a component body having a pair of lands arranged spaced apart from each other on a substrate, solder respectively arranged on the lands, dielectric layers and internal electrode layers stacked together, the component body including a pair of main surfaces opposing each other in a stacking direction, a pair of side surfaces opposing each other in a width direction perpendicular to the stacking direction, and a pair of end surfaces opposing each other in a length direction perpendicular to the stacking direction and the width direction, and a pair of external electrodes respectively arranged on each of the end surfaces, each of the external electrodes being connected to a respective land via the solder, wherein each of the external electrodes includes an extension portion extending to at least a portion of each of the main surfaces and each of the side surfaces, and wherein, when a direction perpendicular to the surface of the substrate is defined as a Z direction, the dimension of the solder in the Z direction, which is located in the region between the land and the extension portion, is 1 μm or more and 100 μm or less.

[0074] <2> The mounting structure according to <1>, wherein at least one of the substrate and the land is provided with a support member for supporting the component body.

[0075] <3> The mounting structure according to <2>, wherein the support member includes an insulating material.

[0076] <4> The electronic component mounting structure described in <2> or <3>, wherein the support member has a first support member arranged in the region between the pair of lands, and the Z-direction dimension of the first support member is in the range of 1 μm or more and 100 μm or less, obtained by subtracting the Z-direction dimension of the land from the Z-direction dimension of the first support member.

[0077] <5> The mounting structure of an electronic component described in any one of <2> to <4>, wherein the support member has a second support member arranged in an area sandwiched between the land and the extension portion, and the dimension of the second support member in the Z direction is 1 μm or more and 100 μm or less.

[0078] <6> An electronic component mounting structure according to any one of <1> to <5>, comprising: a pair of lands arranged spaced apart on a substrate; solder respectively arranged on the lands; a component body having laminated dielectric layers and internal electrode layers, the component body including a pair of main surfaces opposing each other in a stacking direction, a pair of side surfaces opposing each other in a width direction perpendicular to the stacking direction, and a pair of end surfaces opposing each other in a length direction perpendicular to the stacking direction and the width direction; and external electrodes respectively arranged on the end surfaces, the external electrodes being connected to the lands via the solder, wherein each of the external electrodes includes an extension portion extending to at least a part of each of the main surfaces and each of the side surfaces, and wherein, when a direction substantially perpendicular to a surface of the substrate is defined as a Z direction, the distance in the Z direction between the land and the extension portion is 1 μm or more and 100 μm or less.

[0079] REFERENCE SIGNS LIST 1 Mounting structure 10 Multilayer ceramic capacitor (electronic component) 11 Component body 16 External electrode 16b End face covering portion 16c Extension portion 17a Main surface 17b Side surface 17c End face 20 Substrate 22a Insulating film (second support member and insulating material) 22b Insulating film (first support member and insulating material) 30 Land 40 Solder 50 Support member (first support member) 51 Block member (first support member) 52 Resist film portion (first support member and insulating material) 121 Dielectric layer 122 Internal electrode layer

Claims

1. a pair of lands spaced apart from each other on the substrate; solder disposed on each of the lands; an electronic component having a component body having laminated dielectric layers and internal electrode layers, the component body including a pair of main surfaces opposing each other in a lamination direction, a pair of side surfaces opposing each other in a width direction perpendicular to the lamination direction, and a pair of end faces opposing each other in a length direction perpendicular to the lamination direction and the width direction; and a pair of external electrodes respectively disposed on each of the end faces, each of the external electrodes being connected to a corresponding one of the lands via the solder; Equipped with each of the external electrodes includes an extension portion extending to at least a part of the main surface and the side surface; If the direction perpendicular to the surface of the substrate is defined as the Z direction, The mounting structure of an electronic component, wherein the dimension in the Z direction of the solder arranged in the region between the land and the extension portion is 1 μm or more and 100 μm or less.

2. 2. The electronic component mounting structure according to claim 1, further comprising a support member for supporting the component body on at least one of the substrate and the land.

3. The electronic component mounting structure according to claim 2 , wherein the support member includes an insulating material.

4. the support member has a first support member disposed in a region between the pair of lands, 4. The electronic component mounting structure according to claim 2, wherein the Z-direction dimension of the first support member is in a range of 1 μm or more and 100 μm or less, the Z-direction dimension of the land and the Z-direction dimension of the extension portion being subtracted from the Z-direction dimension of the first support member.

5. the support member has a second support member disposed in a region between the land and the extension portion, 4. The electronic component mounting structure according to claim 2, wherein the dimension of the second support member in the Z direction is not less than 1 [mu]m and not more than 100 [mu]m.

6. a pair of lands spaced apart from each other on the substrate; solder disposed on each of the lands; an electronic component having laminated dielectric layers and internal electrode layers, the component body including a pair of main surfaces opposing each other in a lamination direction, a pair of side surfaces opposing each other in a width direction perpendicular to the lamination direction, and a pair of end faces opposing each other in a length direction perpendicular to the lamination direction and the width direction; and external electrodes respectively disposed on the end faces, the external electrodes being connected to the lands via the solder; Equipped with each of the external electrodes includes an extension portion extending to at least a part of each of the main surfaces and each of the side surfaces; If the direction substantially perpendicular to the surface of the substrate is defined as the Z direction, a distance in the Z direction between the land and the extension portion being 1 μm or more and 100 μm or less;