JP2015222833A - Capacitor, capacitor mounting structure, and taping electronic component train - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress acoustic noise furthermore in a capacitor mounting structure.SOLUTION: In a capacitor, t2/t1>0.15 and t3/t1>0.15 are satisfied, where t1 represents a dimension along a thickness direction of a first region A1 including first and second internal electrodes 11, 12 provided therein, in a capacitor body 10, t2 represents a dimension along a thickness direction of a second region A2 located closer to a first main surface 10a side than the first region A1, in the capacitor body 10, and t3 represents a dimension along a thickness direction of a third region A3 located closer to a second main surface 10b side than the first region A1, in the capacitor body 10.

Description

  The present invention relates to a capacitor, a capacitor mounting structure, and a taping electronic component series.

  Currently, capacitors such as multilayer ceramic capacitors are used in many electronic components.

  When the voltage applied to the multilayer ceramic capacitor changes, the multilayer ceramic capacitor may be distorted. The distortion of the multilayer ceramic capacitor is transmitted to the circuit board on which the multilayer ceramic capacitor is mounted via the bonding material. Along with this, the circuit board vibrates. When the vibration frequency of the circuit board is about 20 Hz to 20 kHz, the vibration of the circuit board is recognized as sound. The generation of sound in the frequency band that can be heard by humans is called “acoustic noise”. For example, this noise is a problem in various electronic devices such as mobile communication terminals such as televisions, personal computers, and mobile phones.

  In Patent Document 1, it is possible to suppress squealing by making the suppression region located on one side of the capacitor region facing the first and second internal electrodes thicker than the suppression region located on the other side. Is described.

JP 2013-38332 A

  There is a demand for further suppressing noise in the capacitor mounting structure.

  A main object of the present invention is to further suppress squeal in a capacitor mounting structure.

  The capacitor according to the present invention includes a capacitor body and first and second internal electrodes. The capacitor main body has first and second main surfaces, first and second side surfaces, and first and second end surfaces. The first and second main surfaces extend along the length direction and the width direction. The first and second side surfaces extend along the length direction and the thickness direction. The first and second end faces extend along the width direction and the thickness direction. The first and second internal electrodes are provided in the capacitor body. The first and second internal electrodes are opposed to each other via the ceramic portion. The ceramic portion includes a ferroelectric ceramic. A dimension along the thickness direction of the first region in which the first and second internal electrodes are provided in the capacitor body is defined as t1. The dimension along the thickness direction of the 2nd area | region located in the 1st main surface side rather than a 1st area | region among capacitor bodies is set to t2. A dimension along the thickness direction of the third region located on the second main surface side of the first region of the capacitor body is defined as t3. t2 / t1> 0.07 and t3 / t1> 0.07 are satisfied.

  In the capacitor according to the present invention, the shortest distance along the width direction from the portion where both the first and second internal electrodes of the capacitor main body are provided to the first side surface is w2, and the first and second capacitor main bodies are defined as w2. Preferably, t2 and t3 are larger than w2 and w3, respectively, where w3 is the shortest distance along the width direction from the portion where both of the two internal electrodes are provided to the second side surface.

  In the capacitor according to the present invention, it is preferable that 2.0> t3 / t2> 0.5 is satisfied.

  In the capacitor according to the present invention, it is preferable that t2 and t3 are substantially equal.

  In the capacitor according to the present invention, the first internal electrode and the second internal electrode may face each other in the thickness direction.

  A capacitor mounting structure according to the present invention includes the capacitor according to the present invention and a mounting substrate on which the capacitor is mounted. A capacitor is mounted such that the second main surface faces the mounting substrate.

  The taping electronic component series according to the present invention includes the capacitor according to the present invention and a tape provided in the longitudinal direction and provided with a plurality of recesses into which the capacitor is inserted. The capacitor is arranged such that the second main surface faces the bottom surface of the recess.

  According to the present invention, noise can be further suppressed in the capacitor mounting structure.

It is a typical perspective view of the capacitor concerning one embodiment of the present invention. It is typical sectional drawing in line II-II of FIG. FIG. 3 is a schematic cross-sectional view taken along line III-III in FIG. 1. It is typical sectional drawing of the taping electronic component series in one Embodiment of this invention. It is a typical sectional view of a mounting structure of a capacitor in one embodiment of the present invention. It is a typical perspective view of the capacitor concerning a modification. It is the photograph of the cross section along the width direction and thickness direction in the center of the length direction of the capacitor | condenser actually produced. It is a schematic diagram showing expansion and contraction of a capacitor when both t2 / t1 and t3 / t1 are small. It is a schematic diagram showing expansion and contraction of a capacitor when t2 / t1 is large and t3 / t1 is small. It is a schematic diagram showing expansion and contraction of a capacitor when both t2 / t1 and t3 / t1 are large.

  Hereinafter, an example of the preferable form which implemented this invention is demonstrated. However, the following embodiment is merely an example. The present invention is not limited to the following embodiments.

  Moreover, in each drawing referred in embodiment etc., the member which has a substantially the same function shall be referred with the same code | symbol. The drawings referred to in the embodiments and the like are schematically described. A ratio of dimensions of an object drawn in a drawing may be different from a ratio of dimensions of an actual object. The dimensional ratio of the object may be different between the drawings. The specific dimensional ratio of the object should be determined in consideration of the following description.

  FIG. 1 is a schematic perspective view of a capacitor according to the present embodiment. 2 is a schematic cross-sectional view taken along line II-II in FIG. 3 is a schematic cross-sectional view taken along line III-III in FIG.

  The capacitor 1 shown in FIGS. 1 to 3 is a multilayer ceramic capacitor. The present invention is suitable for the capacitor 1 having a large capacitance that easily generates squeal, and is particularly suitable for the capacitor 1 having a capacitance of 1 μF or more or 10 μF or more.

  The capacitor 1 includes a capacitor body 10. The capacitor body 10 has a substantially rectangular parallelepiped shape. In addition to the rectangular parallelepiped, the substantially rectangular parallelepiped includes a rectangular parallelepiped whose corners and ridge lines are chamfered or rounded.

  The capacitor body 10 includes first and second main surfaces 10a and 10b, first and second side surfaces 10c and 10d, and first and second end surfaces 10e and 10f (see FIG. 2). The first and second main surfaces 10a and 10b extend along the length direction L and the width direction W, respectively. The length direction L and the width direction W are orthogonal to each other. The first and second side surfaces 10c and 10d extend along the length direction L and the thickness direction T, respectively. The thickness direction T is orthogonal to each of the length direction L and the width direction W. The first and second end faces 10e, 10f extend along the width direction W and the thickness direction T, respectively.

  The dimension along the length direction L of the capacitor body 10 is preferably 0.6 mm to 1.8 mm. The dimension along the width direction W of the capacitor body 10 is preferably 0.3 mm to 1.0 mm. The dimension along the thickness direction T of the capacitor body 10 is preferably 0.3 mm to 1.2 mm.

The capacitor body 10 is made of ferroelectric ceramics in order to obtain a large capacitance. Specific examples of dielectric ceramics include BaTiO ₃ , CaTiO ₃ , SrTiO _{3 and the} like. Depending on the characteristics required for the capacitor 1, subcomponents such as Mn compound, Mg compound, Si compound, Fe compound, Cr compound, Co compound, Ni compound, rare earth compound are appropriately added to the capacitor body 10. May be. The relative dielectric constant of the ferroelectric ceramic is preferably 2000 or more, and more preferably 3000 or more. In this case, a capacitance of 1 μF or more or 10 μF or more can be realized within the above-described dimension range of the capacitor body 10. Such a capacitor 1 is liable to squeal, and the present invention can be suitably applied.

When a Mn compound is added to the ferroelectric ceramic, the Mn content in the dielectric ceramic is preferably 0.5 mol parts or less with respect to 100 mol parts of BaTiO ₃ , and 0.2 mol parts The following is preferable. From the viewpoint of improving the reliability of the capacitor 1, the Mn compound is preferably 0.05 mol part or more.

  As shown in FIGS. 2 and 3, a plurality of first internal electrodes 11 and a plurality of second internal electrodes 12 are provided inside the capacitor body 10. The first internal electrode 11 and the second internal electrode 12 are opposed to each other through the ceramic portion 10g. In the present embodiment, the first internal electrodes 11 and the second internal electrodes 12 are alternately provided along the thickness direction T. The first internal electrode 11 and the second internal electrode 12 are opposed to each other through the ceramic portion 10g in the thickness direction T. However, the present invention is not limited to this configuration. In the present invention, the first internal electrode and the second internal electrode may be opposed in the width direction W or may be opposed in the length direction L, for example.

  The present invention is particularly suitable for a capacitor in which the number of laminated ceramic portions 10g sandwiched between the first internal electrode 11 and the second internal electrode 12 is 350 or more. That is, the total number of internal electrodes 11 and 12 is preferably 351 or more. In order to include 350 or more ceramic parts 10g in the capacitor body having a limited thickness, the thickness of the ceramic part 10g is preferably 1 μm or less. When the thickness of the ceramic portion 10g is 1 μm or less, the electrostatic capacity per unit area of the surface orthogonal to the thickness direction T of the ceramic portion 10g is increased, so that squeal is likely to occur. Therefore, the present invention is applied to a capacitor 1 having a capacitance of 1 μF or more and a ceramic portion 10 g of 1 μm or less, and further to a capacitor 1 having a capacitance of 10 μF or more and a ceramic portion 10 g of 1 μm or less. It can be used suitably.

  The first internal electrode 11 is provided along the length direction L and the width direction W. The first internal electrode 11 is drawn out to the first end face 10e, and is drawn out to the first and second main faces 10a and 10b, the first and second side faces 10c and 10d, and the second end face 10f. Not.

  The second internal electrode 12 is provided along the length direction L and the width direction W. The second internal electrode 12 is drawn out to the second end face 10f, and is drawn out to the first and second main faces 10a and 10b, the first and second side faces 10c and 10d, and the first end face 10e. Not.

  Each of the first and second internal electrodes 11 and 12 can be made of at least one of Pt, Au, Ag, Cu, Ni, Cr, and the like, for example.

  A first external electrode 13 is provided on the first end face 10e. The first external electrode 13 extends from the first end face 10e to the first and second main faces 10a and 10b and the first and second side faces 10c and 10d. The first external electrode 13 is electrically connected to the first internal electrode 11 at the first end face 10e.

  A second external electrode 14 is provided on the second end face 10f. The second external electrode 14 extends from the second end face 10f to the first and second main faces 10a and 10b and the first and second side faces 10c and 10d. The second external electrode 14 is electrically connected to the second internal electrode 12 at the second end face 10f.

  Each of the first and second external electrodes 13 and 14 can be made of at least one of Pt, Au, Ag, Cu, Ni, Cr, and the like, for example.

  FIG. 4 is a schematic cross-sectional view of the taping electronic component series in the present embodiment.

  As shown in FIG. 4, the taping electronic component series 2 is obtained by fixing a plurality of capacitors 1 by taping. The taping electronic component series 2 has a long tape 20. The tape 20 includes a long carrier tape 21 and a long cover tape 22. The carrier tape 21 has a plurality of recesses 21a that are spaced apart from each other along the longitudinal direction. The cover tape 22 is provided on the carrier tape 21 so as to cover the plurality of recesses 21a. The capacitor 1 is accommodated in each of the plurality of recesses 21a. The plurality of capacitors 1 are arranged such that the second main surface 10b faces the bottom surface side of the recess 21a. For this reason, the plurality of capacitors 1 of the taping electronic component series 2 are mounted so that they are attracted and held on the first main surface 10a side, and the second main surface 10b side faces the wiring board side.

  FIG. 5 is a schematic cross-sectional view of the capacitor mounting structure in the present embodiment.

  As shown in FIG. 5, the capacitor mounting structure 3 includes a capacitor 1 and a mounting substrate 30. The capacitor 1 is mounted on the mounting substrate 30 such that the second main surface 10b faces the mounting substrate 30 side.

  The first and second internal electrodes 11 and 12 are provided in a part of the capacitor body 10 in the thickness direction T. The capacitor body 10 includes a first region A1 in which the first and second internal electrodes 11 and 12 are provided, and a second region located on the first main surface 10a side with respect to the first region A1. A2 and a third region A3 located on the second main surface 10b side with respect to the first region A1. Since the first region A1 is a region that exhibits a function as a capacitor, it may be referred to as an effective region. On the other hand, the second and third regions A2 and A3 are regions that do not exhibit a function as a capacitor, and may be referred to as invalid regions. Since the thickness of the second and third regions A2 and A3 is thicker than that of a general capacitor having a large capacitance, the second and third regions A2 and A3 are dielectric ceramics that are thicker than the ceramic portion 10g. It is formed by laminating a plurality of sheets.

  Here, as shown in FIG. 3, the dimension along the thickness direction T of the first region A1 is defined as t1. A dimension along the thickness direction T of the second region A2 is assumed to be t2. A dimension along the thickness direction T of the third region A3 is defined as t3. The distance along the width direction W from the portion of the capacitor body 10 where both the first and second internal electrodes 11 and 12 are provided to the first side surface 10c is w2, and the first and second of the capacitor body 10 are the same. The distance along the width direction W from the portion where both of the internal electrodes 11 and 12 are provided to the second side surface 10d is defined as w3. Each of t2 and t3 is preferably larger than w2 and w3. That is, each of t2 and t3 is preferably larger than the larger of w2 and w3. Capacitor having a dimension along the length direction L of the capacitor body 10 of 1.7 mm or less and a dimension along the width direction W of 0.9 mm or less and a capacitance of 1 μF or more ensures the capacitance and is resistant to moisture. From the viewpoints of performance and processing accuracy, it is opposite to the general case that w2 and w3 are set to t2 and t3 or more.

  Note that t2 and t3 can be measured by polishing the capacitor 1 to expose a cross section perpendicular to the length direction L passing through the center of the capacitor body 10 and at the position of the central portion in the width direction W in the cross section. it can. w2 and w3 can be measured at the position of the central portion of the cross section in the length direction L by exposing the cross section perpendicular to the length direction L passing through the center of the capacitor body 10 by polishing the capacitor 1. .

  Conventionally, from the viewpoint of suppressing noise in a mounting structure in which a capacitor is mounted on a mounting board so that the second main surface faces the mounting board, it is preferable to increase the thickness dimension of the third region, The thickness dimension of region 2 is considered to have little effect on squeal. On the other hand, from the viewpoint of increasing the capacitance of the capacitor, it is preferable to increase the thickness dimension of the first region. Therefore, by increasing the thickness dimension of the third region and decreasing the thickness dimension of the second region, the second and second regions are suppressed in order to suppress the noise while suppressing the decrease in the capacitance of the capacitor. Of the three regions, a design that increases the thickness dimension of only the third region is generally employed.

  However, as a result of intensive studies by the present inventors, it was found that not only the third region but also the second region can be made thicker so that squeal can be further suppressed. In the capacitor 1 of the present embodiment, both t2 / t1> 0.07 and t3 / t1> 0.07 are satisfied. Therefore, in the mounting structure 3 on which the capacitor 1 is mounted, squeal is further suppressed.

  In the above-mentioned conventional idea, among the ineffective regions having the required capacitance and the allowable thickness from the outer dimensions, as many regions as possible are allocated to the third region, and the second region is kept to a minimum. Can be considered. However, as a result of intensive studies, the present inventors have found that if the thickness dimension of the second region is too small, squealing is not sufficiently suppressed. From the viewpoint of sufficiently suppressing the squeal, when the dimension along the thickness direction T of the capacitor body 10 is t0, t1 / t0> 0.6 and 1.2> t3 / t2> 0.8 are satisfied. It is preferred that

  If a design is adopted in which the thickness dimension t2 of the second region is reduced and the thickness dimension t3 of only the third region is increased as in the prior art, the first main surface is opposed to the mounting substrate. It is necessary to identify the main surface and the second main surface, that is, to identify the upper and lower surfaces and to align the directions. Therefore, for example, as in Patent Document 1, it is necessary to provide an identification mark such as exposing an internal electrode or providing a layer having a different color on the outer surface of the capacitor. However, the addition of these identification marks has deteriorated the characteristics and reliability of the capacitor and has complicated the manufacture of the capacitor.

  On the other hand, when both t2 and t3 satisfy the above conditions, it is possible to suppress squeal even if the main surface facing the mounting substrate is either the first main surface or the second main surface. Therefore, when the capacitor 1 is mounted or disposed on the tape 20, it is not necessary to identify the first main surface and the second main surface, that is, the upper and lower surfaces. From this viewpoint, it is preferable that t2 and t3 satisfy the condition of 2.0> t3 / t2> 0.5. In that case, even if any of the first main surface and the second main surface faces the mounting substrate, there is little difference in the effect of suppressing the squeal. It is preferable that t2 and t3 are substantially equal. Here, that t2 and t3 are substantially equal means that t3 is 0.9 to 1.1 times t2.

  From the viewpoint of more effectively suppressing noise, it is more preferable that t2 / t1> 0.15 and t3 / t1> 0.15 are satisfied. However, if t2 / t1 and t3 / t1 are too large, the capacitance of the capacitor 1 may be too small. Alternatively, if it is attempted to secure the capacitance of the capacitor 1, the thickness dimension t0 of the capacitor 1 becomes too large, and the mounting posture may become unstable. Therefore, it is preferable that t2 / t1 <0.3. It is preferable that t3 / t1 <0.3.

  When the dimension along the width direction of the capacitor body 10 is w0, it is preferable that t0 and w0 are substantially equal. In that case, the posture stability of the capacitor 1 is improved when the capacitor 1 is mounted and after the capacitor 1 is mounted. In this case, the mounting or taping with the main surface and the side surface being discriminated or oriented in the same direction can be performed by magnetic force using the surface direction of the internal electrode. Here, that t0 and w0 are substantially equal means that w0 is 0.9 to 1.1 times t0.

  However, t0 may be larger than w0. In this case, there is an advantage that mounting or taping with the main surface and the side surface being discriminated or oriented with ease is facilitated by the difference in outer shape.

  Depending on the design conditions of the capacitor body 10, the main surface and the side surface can be identified based on the difference in color intensity between the main surface and the side surface. That is, when at least one of w2 and w3 is smaller than t2 and t3, as shown in FIG. 6, the internal electrodes 11 and 12 are seen through the side surfaces 10c and 10d, and the colors of the side surfaces 10c and 10d are changed. It becomes darker than the color of the main surface. Alternatively, the color of the side surfaces 10c, 10d becomes darker than the color of the main surfaces 10a, 10b due to the diffusion of the inorganic components contained in the internal electrodes 11, 12. Alternatively, the color of the side gap portion, which is a portion between the side surfaces 10c and 10d and the effective region (first region A1), becomes darker than the colors of the second and third regions A2 and A3, and the side surface 10c, The color of 10d is darker than the colors of the main surfaces 10a and 10b. The colors of the side surfaces 10 c and 10 d become darker in a strip shape extending in the length direction corresponding to the internal electrodes 11 and 12. In FIG. 6, hatching is added to the dark portion.

  The reason why the color of the side gap portion is darker than that of the second and third regions A2 and A3 is considered to be as follows. That is, since the thin side gap is close to the outer surface, the pores in the side gap portion are difficult to escape. On the contrary, the thick pores in the second and third regions A2 and A3 are difficult to escape, and the pores are likely to remain. If the pores remain, the color appears light. This is because the remaining pores diffusely reflect light. As shown in FIG. 7, since the thicknesses w1 and w2 of the side gap portions are thinner than the thicknesses t1 and t2 of the second and third regions A2 and A3, the residual rate of pores in the side gap portions is the second and third. It becomes lower than the third regions A2 and A3, and the color of the side surface, which is the outer surface of the side gap portion, becomes lighter on the main surface, which is the outer surface of the second and third regions A2, A3. Therefore, it is possible to distinguish the side surface from the main surface by the difference in color density.

In order to clarify the difference in color intensity, it is preferable that at least one of w2 and w3 is 10 μm or more smaller than t2 and t3, and more preferably 30 μm or less. Alternatively, at least one of w2 and w3 is preferably 80 μm or less, and more preferably 60 μm or less. Alternatively, it is preferable to make the entire color of the dielectric ceramic light and clarify the color difference between the side surface and the main surface. As for the color of the dielectric ceramic, as the Mn content is smaller, the brown color becomes lighter and approaches white, and the color difference becomes clear. Therefore, in order to identify the side surface and the main surface by the difference in color, the Mn content with respect to 100 mol parts of BaTiO ₃ is preferably 0.5 mol parts or less. The Mn content with respect to 100 mol parts of BaTiO ₃ is preferably 0.2 mol parts or less.

  In particular, when the internal electrodes 11 and 12 contain Ni as a main component as a metal component, Ni diffuses into the dielectric, and the difference in color density becomes clearer. Even in this case, the color of the side surfaces 10c and 10d is darker than the color of the main surfaces 10a and 10b.

  The colors of the side surfaces 10c and 10d and the main surfaces 10a and 10b can be confirmed visually or with an optical microscope. The color difference can also be confirmed by observing the cross section of the ceramic body 10 with an optical microscope. The porosity remaining rate is measured as an area ratio by observing a cross section of the ceramic body 10 with a scanning electron microscope (SEM). However, the difference in the remaining rate in which the color difference appears may be buried in the measurement error. The distribution state of Ni by diffusion can be confirmed from an element mapping image obtained by observing with an energy dispersive X-ray (EDX) analyzer attached to the SEM.

  The Mn content is measured as follows. That is, 40 multilayer ceramic capacitors 1 are immersed in a sample bottle containing 30 mL of 0.2 mol / L adipic acid solution. The sample bottle was sealed and left at a temperature of 85 ° C. for 120 hours. After cooling, the multilayer ceramic capacitor 1 is taken out, and the multilayer ceramic capacitor 1 is washed with pure water until the adipic acid solution reaches 50 mL. Next, among these, the ceramic components contained in 5 mL of the eluate are quantified by ICP emission spectroscopy, and the total of detected elution elements is determined in μmol units.

  The reason why the sound pressure of the squeal can be suppressed more by increasing both of the t2 / t1 and t3 / t1 than when increasing only one of them is considered as follows. As can be understood from the comparison between FIG. 8 and FIG. 9, when only t2 / t1 is increased, the binding force on the second region of the capacitor body is increased. For this reason, the force in the thickness direction T acting on the outside from the capacitor on the first main surface is weakened, and the force in the thickness direction T acting on the outside from the capacitor on the second main surface is strengthened by the reaction. As a result, the force toward the capacitor in the length direction L of the second main surface is weakened, so that deformation of the mounting substrate on which the capacitor is mounted is suppressed. On the other hand, when only t3 / t1 is increased, the distance between the first region of the capacitor body and the second main surface is increased. As a result of the second main surface moving away from the first region where distortion occurs, the force toward the capacitor in the length direction L of the second main surface is weakened, thereby suppressing deformation of the mounting substrate on which the capacitor is mounted. Is done. As shown in FIG. 10, when both t2 / t1 and t3 / t1 are increased, a synergistic effect of the reaction of restraint reaction caused by t2 / t1 and the action of thickness caused by t3 / t1 occurs, and t2 The reduction of the force toward the capacitor in the length direction L generated on the second main surface when only / t1 is increased, and the length direction L capacitor generated on the second main surface when only t3 / t1 is increased Further, the force toward the capacitor in the length direction L generated on the second main surface is further reduced than the sum of the reduction in the force toward Thus, it is considered that the squeal is more effectively suppressed by the synergistic effect obtained by increasing both t2 / t1 and t3 / t1. In addition, in this specification, the force along the length direction L applied to the main surface is obtained by evaluating the force toward the center side in the length direction L of the capacitor as a positive direction.

  Hereinafter, the present invention will be described in more detail on the basis of specific examples. However, the present invention is not limited to the following examples, and may be appropriately modified and implemented without departing from the scope of the present invention. Is possible.

Example 1
A capacitor mounting structure was fabricated under the following conditions. The sound pressure of the squeal of the fabricated capacitor mounting structure was measured under the following post-firing design conditions.

[Conditions for capacitors]
Capacitor body dimensions: L dimension 1.10 mm, W dimension 0.59 mm, T dimension 0.69 mm
t1: 520 μm
t2: 85 μm
t3: 85 μm
w2: 55 μm
w3: 55 μm
Number of ceramic parts: 391 Capacitance: 4.7 μF
[Sound pressure measurement conditions]
A capacitor was mounted on a mounting board using solder, and sample S was produced. Next, the sample S was installed in the anechoic box of the measuring apparatus, and an AC voltage of 1 Vpp in a frequency band of 1 kHz to 6 kHz was applied to the capacitor. In this state, the squeak was collected by a sound collecting microphone arranged 3 mm above the multilayer capacitor of sample S. And the maximum sound pressure level of the sound collected with the sound collector and the FFT analyzer (CF-5220 by Ono Sokki Co., Ltd.) was measured.

(Example 2)
Except for the following conditions, a capacitor mounting structure was produced in the same manner as in Example 1, and the sound pressure level of the squeal was measured.

Capacitor body dimensions: L dimension 1.10 mm, W dimension 0.64 mm, T dimension 0.82 mm
t1: 700 μm
t2: 60 μm
t3: 60 μm
w2: 50 μm
w3: 50 μm
Number of ceramic parts: 409 electrostatic capacity: 10 μF

(Example 3)
Except for the following conditions, a capacitor mounting structure was produced in the same manner as in Example 1, and the sound pressure level of the squeal was measured.

Capacitor body dimensions: L dimension 1.60 mm, W dimension 0.91 mm, T dimension 1.11 mm
t1: 820 μm
t2: 140 μm
t3: 140 μm
w2: 70 μm
w3: 70 μm
Number of ceramic parts: 524 Capacitance: 22 μF

(Comparative Example 1)
A capacitor mounting structure was prepared and the sound pressure of the squeal was measured in the same manner as in Example 1 except that t2 was made equal to w2 and the T dimension was reduced accordingly.

(Comparative Example 2)
A capacitor mounting structure was prepared and the sound pressure of the squeal was measured in the same manner as in Example 2 except that t2 was made equal to w2 and the T dimension was reduced accordingly.

(Comparative Example 3)
A capacitor mounting structure was fabricated and the sound pressure of the squeal was measured in the same manner as in Example 3 except that t2 was made equal to w2 and the T dimension was reduced accordingly.

  As a result, the sound pressure level of the capacitor of Example 1 was lower by about 8.1 dB than the sound pressure level of the capacitor of Comparative Example 1. The sound pressure level of the capacitor of Example 2 was about 9.1 dB lower than the sound pressure level of the capacitor of Comparative Example 2. The sound pressure level of the capacitor of Example 3 was about 6.5 dB lower than the sound pressure level of the capacitor of Comparative Example 3.

  Next, the following experiment was conducted to clarify the thickness t2 of the second region and the thickness t3 of the third region that can effectively suppress squeal.

(Comparative Example 4)
Except for the following conditions, a capacitor mounting structure was produced in the same manner as in Example 1, and the sound pressure level of the squeal was measured. The results are shown in Table 1.

Capacitor body dimensions: L dimension 1.75 mm, W dimension 0.85 mm, T dimension 0.85 mm
t1: 780 μm
t2: 40 μm
t3: 40 μm
t2 / t1: 0.05
t3 / t1: 0.05
w2: 100 μm
w3: 100 μm
Number of ceramic parts: 345 Capacitance: 10 μF

Example 4
A capacitor mounting structure was produced in the same manner as in Comparative Example 4 except that the following conditions were satisfied, and the sound pressure level of the squeal was measured. The results are shown in Table 1.

t1: 780 μm
t2: 55 μm
t3: 55 μm
t2 / t1: 0.07
t3 / t1: 0.07

(Example 5)
A capacitor mounting structure was produced in the same manner as in Comparative Example 4 except that the following conditions were satisfied, and the sound pressure level of the squeal was measured. The results are shown in Table 1.

t1: 780 μm
t2: 80 μm
t3: 80 μm
t2 / t1: 0.1
t3 / t1: 0.1

(Example 6)
A capacitor mounting structure was produced in the same manner as in Comparative Example 4 except that the following conditions were satisfied, and the sound pressure level of the squeal was measured. The results are shown in Table 1.

t1: 780 μm
t2: 120 μm
t3: 120 μm
t2 / t1: 0.15
t3 / t1: 0.15

(Example 7)
A capacitor mounting structure was produced in the same manner as in Comparative Example 4 except that the following conditions were satisfied, and the sound pressure level of the squeal was measured. The results are shown in Table 1.

t1: 780 μm
t2: 155 μm
t3: 155 μm
t2 / t1: 0.2
t3 / t1: 0.2

  From the results shown in Table 1, it can be seen that the sound pressure can be reduced to 60 dB or less by setting t2 / t1 and t3 / t1 to 0.07 or more. Further, it can be seen that by setting t2 / t1 and t3 / t1 to 0.15 or more, the sound pressure is reduced to half that of 60 dB, that is, 54 dB or less, which is −6 dB.

1: Capacitor 2: Taping electronic component series 3: Mounting structure 10: Capacitor body 10a: First main surface 10b: Second main surface 10c: First side surface 10d: Second side surface 10e: First end surface 10f: second end face 10g: ceramic part 11: first internal electrode 12: second internal electrode 13: first external electrode 14: second external electrode 20: tape 21: carrier tape 21a: recess 22: Cover tape 30: mounting substrate A1: first area A2: second area A3: third area

Claims (1)

First and second main surfaces extending along the length direction and the width direction, first and second side surfaces extending along the length direction and the thickness direction, and first extending along the width direction and the thickness direction And a capacitor body having a second end surface;
First and second internal electrodes provided in the capacitor body and facing each other with a ceramic portion interposed therebetween;
With
The ceramic part includes a ferroelectric ceramic,
Of the capacitor body, the dimension along the thickness direction of the first region where the first and second internal electrodes are provided is t1,
Of the capacitor main body, the dimension along the thickness direction of the second region located closer to the first main surface than the first region is t2,
Of the capacitor body, when the dimension along the thickness direction of the third region located on the second main surface side of the first region is t3,
A capacitor in which t2 / t1> 0.07 and t3 / t1> 0.07 are satisfied.