US-12620533-B1 - Electronic component and method of manufacturing electronic component

US12620533B1US 12620533 B1US12620533 B1US 12620533B1US-12620533-B1

Abstract

An electronic component includes a functional part, a first cover, and a second cover. The first cover overlaps the functional part from a first side in a first direction. The second cover overlaps the functional part from a second side, the second side being on an opposite side from the first side. The first cover includes one or more first ceramic layers and one or more first conductor layers stacked in an alternating manner with the one or more first ceramic layers. The second cover includes one or more second ceramic layers and one or more second conductor layers stacked in an alternating manner with the one or more second ceramic layers. The configuration of the first cover and the configuration of the second cover are asymmetrical with each other with respect to the functional part.

Inventors

Tatsuya Suzuki
Hirotoshi KII
Satoru NAOKAWA

Assignees

KYOCERA CORPORATION

Dates

Publication Date: 20260505
Application Date: 20250603

Claims (19)

1 . An electronic component comprising: a functional part comprising multiple internal electrodes and multiple dielectric layers stacked in an alternating manner in a first direction; a first cover overlapping the functional part from a first side in the first direction; and a second cover overlapping the functional part from a second side, the second side being on an opposite side from the first side, wherein the first cover includes one or more first ceramic layers, and one or more first conductor layers stacked in an alternating manner with the one or more first ceramic layers, the second cover includes one or more second ceramic layers, and one or more second conductor layers stacked in an alternating manner with the one or more second ceramic layers, the one or more first conductor layers include a first conductor layer that is thicker than any of the multiple internal electrodes; and the one or more second conductor layers include a second conductor layer that is thicker than any of the multiple internal electrodes, and a configuration of the first cover and a configuration of the second cover are asymmetrical with each other with respect to the functional part.
2 . The electronic component according to claim 1 , wherein the first cover and the second cover differ from each other in terms of at least one selected from a group consisting of thicknesses of corresponding layers, materials of corresponding layers, and numbers of conductor layers.
3 . The electronic component according to claim 1 , wherein the first cover is thicker than the second cover, and a total thickness of the one or more first conductor layers is greater than a total thickness of the one or more second conductor layers.
4 . The electronic component according to claim 1 , wherein a thickness of the first conductor layer positioned farthest toward the first side, among the one or more first conductor layers, is greater than a thickness of the second conductor layer positioned farthest toward the second side, among the one or more second conductor layers.
5 . The electronic component according to claim 1 , wherein a thickness of the functional part in the first direction is smaller than both a length of the functional part in a second direction and a length of the functional part in a third direction, the second direction being perpendicular to the first direction and the third direction being perpendicular to the first direction and the second direction.
6 . The electronic component according to claim 1 , further comprising: a first external electrode covering the first cover; and a second external electrode covering the second cover, wherein each of the one or more first conductor layers includes a part exposed to outside the first cover and bonded to the first external electrode, and each of the one or more second conductor layers includes a part exposed to outside the second cover and bonded to the second external electrode.
7 . The electronic component according to claim 1 , further comprising: a first external electrode covering the first cover; and a second external electrode covering the second cover, wherein the first external electrode includes a part that directly contacts the one or more first ceramic layers, and does not contain a co-material with the one or more first ceramic layers, and the second external electrode includes a part that directly contacts the one or more second ceramic layers, and does not contain a co-material with the one or more second ceramic layers.
8 . The electronic component according to claim 1 , wherein an average particle size of metal particles constituting a main component of the one or more first conductor layers and an average particle size of metal particles constituting a main component of the one or more second conductor layers are respectively larger than an average particle size of ceramic particles constituting a main component of the one or more first ceramic layers and an average particle size of ceramic particles constituting a main component of the one or more second ceramic layers.
9 . The electronic component according to claim 1 , wherein a thickness of the first conductor layer positioned farthest toward the first side and exposed toward the first side from the first cover, among the one or more first conductor layers, is 1.2 times or more and 2.5 times or less a thickness of the second conductor layer positioned farthest toward the second side and exposed toward the second side from the second cover, among the one or more second conductor layers.
10 . The electronic component according to claim 1 , wherein the first conductor layer positioned farthest toward the first side and exposed toward the first side from the first cover, among the one or more first conductor layers, is embedded, from the first side, in the first ceramic layer positioned farthest toward the first side, among the one or more first ceramic layers, and the second conductor layer positioned farthest toward the second side and exposed toward the second side from the second cover, among the one or more second conductor layers, is embedded, from the second side, in the second ceramic layer positioned farthest toward the second side, among the one or more second ceramic layers.
11 . The electronic component according to claim 1 , wherein, in perspective view in the first direction, the one or more first conductor layers and the one or more second conductor layers include parts overlapping a region where the multiple internal electrodes overlap each other.
12 . The electronic component according to claim 1 , wherein the one or more first conductor layers comprise: one or more layers of first electrodes located on a third side in a second direction, which intersects the first direction, relative to a center of the first cover in the second direction; and one or more layers of second electrodes located on a fourth side, opposite to the third side, relative to the center of the first cover, and spaced apart from the one or more layers of first electrodes in the second direction, the one or more second conductor layers comprise: one or more layers of third electrodes located on the third side in the second direction, relative to a center of the second cover in the second direction; and one or more layers of fourth electrodes located on the fourth side, relative to the center of the second cover, and spaced apart from the one or more layers of third electrodes toward the fourth side, a total volume of the one or more layers of first electrodes is greater than a total volume of the one or more layers of third electrodes, and a total volume of the one or more layers of second electrodes is greater than a total volume of the one or more layers of fourth electrodes.
13 . The electronic component according to claim 12 , wherein a total thickness of the one or more layers of first electrodes is greater than a total thickness of the one or more layers of third electrodes, and a total thickness of the one or more layers of second electrodes is greater than a total thickness of the one or more layers of fourth electrodes.
14 . The electronic component according to claim 12 , wherein at least one of the one or more first conductor layers has a length in the second direction of the first electrode that is greater than a length in the second direction of each of the one or more layers of third electrodes, and a length in the second direction of the second electrode that is greater than a length in the second direction of each of the one or more layers of fourth electrodes.
15 . The electronic component according to claim 1 , wherein the first cover is thicker than the second cover.
16 . A method of manufacturing an electronic component, comprising: stacking ceramic green sheets to obtain an unfired multilayer body; and firing the unfired multilayer body, wherein the unfired multilayer body includes an unfired functional part comprising multiple internal conductive paste layers that form multiple internal electrodes and multiple ceramic green sheets that form multiple dielectric layers stacked in an alternating manner in a first direction, an unfired first cover overlapping the unfired functional part from a first side in the first direction, and an unfired second cover overlapping the unfired functional part from a second side, the second side being on an opposite side from the first side, the unfired first cover includes one or more first ceramic green sheets, and one or more first conductive paste layers stacked in an alternating manner with the one or more first ceramic green sheets, the unfired second cover includes one or more second ceramic green sheets, and one or more second conductive paste layers stacked in an alternating manner with the one or more second ceramic green sheets, and the one or more first conductive paste layers include a first conductive paste layer that is thicker than any of the multiple internal conductive paste layers; and the one or more second conductive paste layers include a second conductive paste layer that is thicker than any of the multiple internal conductive paste layers, a configuration of the unfired first cover and a configuration of the unfired second cover are asymmetrical with each other with respect to the unfired functional part.
17 . An electronic component comprising: a functional part; a first cover overlapping the functional part from a first side in a first direction; and a second cover overlapping the functional part from a second side, the second side being on an opposite side from the first side, wherein the first cover includes one or more first ceramic layers, and one or more first conductor layers stacked in an alternating manner with the one or more first ceramic layers, the second cover includes one or more second ceramic layers, and one or more second conductor layers stacked in an alternating manner with the one or more second ceramic layers, and a configuration of the first cover and a configuration of the second cover are asymmetrical with each other with respect to the functional part; wherein the one or more first conductor layers comprise: one or more layers of first electrodes located on a third side in a second direction, which intersects the first direction, relative to a center of the first cover in the second direction, and one or more layers of second electrodes located on a fourth side, opposite to the third side, relative to the center of the first cover, and spaced apart from the one or more layers of first electrodes in the second direction, the one or more second conductor layers comprise: one or more layers of third electrodes located on the third side in the second direction, relative to a center of the second cover in the second direction; and one or more layers of fourth electrodes located on the fourth side, relative to the center of the second cover, and spaced apart from the one or more layers of third electrodes toward the fourth side, a total volume of the one or more layers of first electrodes is greater than a total volume of the one or more layers of third electrodes, and a total volume of the one or more layers of second electrodes is greater than a total volume of the one or more layers of fourth electrodes, and wherein the functional part includes multiple internal electrodes and multiple dielectric layers stacked in an alternating manner in the first direction, a thickness of each of the one or more layers of first electrodes is greater than a thickness of each of the multiple internal electrodes, a thickness of each of the one or more layers of second electrodes is greater than the thickness of each of the multiple internal electrodes, a thickness of each of the one or more layers of third electrodes is greater than the thickness of each of the multiple internal electrodes, and a thickness of each of the one or more layers of fourth electrodes is greater than the thickness of each of the multiple internal electrodes.
18 . The electronic component according to claim 17 , wherein the first cover and the second cover differ from each other in terms of at least one selected from a group consisting of thicknesses of corresponding layers, materials of corresponding layers, and numbers of conductor layers.
19 . The electronic component according to claim 17 , wherein a total thickness of the one or more layers of first electrodes is greater than a total thickness of the one or more layers of third electrodes, and a total thickness of the one or more layers of second electrodes is greater than a total thickness of the one or more layers of fourth electrodes.

Description

CROSS-REFERENCE TO RELATED APPLICATION The present application is a Continuation-in-Part of International Application No. PCT/JP2024/045748, filed on Dec. 24, 2024, the entirety of which is incorporated by reference as if fully set forth herein. BACKGROUND OF THE INVENTION 1. Field of the Invention The present disclosure relates to an electronic component such as a multilayer ceramic capacitor and to a method of manufacturing such an electronic component. 2. Description of the Related Art A known multilayer ceramic capacitor includes ceramic layers and internal electrodes stacked in an alternating manner (see, for example, below mentioned International Publication No. 2012/043740). International Publication No. 2012/043740 discloses a configuration in which a base layer is provided on the top surface of a functional part consisting of the ceramic layers and the internal electrodes. International Publication No. 2012/043740 discloses an issue of warping occurring in capacitors due to the sintering shrinkage rates of ceramic components and metal components. In International Publication No. 2012/043740, the base layer is composed of a ceramic containing metal particles in order to solve this issue. SUMMARY OF THE INVENTION In an aspect of the present disclosure, an electronic component includes a functional part, a first cover, and a second cover. The first cover overlaps the functional part from a first side in a first direction. The second cover overlaps the functional part from a second side, the second side being on an opposite side from the first side. The first cover includes one or more first ceramic layers and one or more first conductor layers stacked in an alternating manner with the one or more first ceramic layers. The second cover includes one or more second ceramic layers and one or more second conductor layers stacked in an alternating manner with the one or more second ceramic layers. A configuration of the first cover and a configuration of the second cover are asymmetrical with each other with respect to the functional part. In an aspect of the present disclosure, a method of manufacturing an electronic component includes stacking ceramic green sheets to obtain an unfired multilayer body, and firing the unfired multilayer body. The unfired multilayer body includes an unfired functional part, an unfired first cover, and an unfired second cover. The unfired first cover overlaps the unfired functional part from a first side. The unfired second cover overlaps the unfired functional part from a second side, the second side being on an opposite side from the first side. The unfired first cover includes one or more first ceramic green sheets and one or more first conductive paste layers stacked in an alternating manner with the one or more first ceramic green sheets. The unfired second cover includes one or more second ceramic green sheets and one or more second conductive paste layers stacked in an alternating manner with the one or more second ceramic green sheets. A configuration of the unfired first cover and a configuration of the unfired second cover are asymmetrical with each other with respect to the unfired functional part. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view illustrating a capacitor according to an embodiment; FIG. 2 is a schematic exploded perspective view of the capacitor in FIG. 1; FIG. 3 is a cross-sectional view taken along line III-III in FIG. 1; FIG. 4 is a schematic diagram for describing a method of manufacturing a capacitor; FIG. 5 is a schematic diagram for describing an example of an action of an embodiment; FIG. 6 is a diagram illustrating warping of capacitors according to Comparative Examples and an Example; FIG. 7 is a diagram illustrating warping of capacitors according to other Comparative Examples and another Example; FIG. 8 is a sectional view illustrating another example relating to asymmetry of a capacitor in a vertical direction; and FIG. 9 is a perspective view illustrating another example relating to the arrangement of terminals. DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments according to the present disclosure will be described while referring to the drawings. The drawings used in the following description are schematic drawings. Therefore, the dimensional ratios and so forth in the drawings do not necessarily match the actual dimensional ratios and so forth. There may be cases where the dimensional ratios and so forth do not match from drawing to drawing. Certain shapes or dimensions etc. may be depicted in an exaggerated fashion, and details may be omitted. However, this does not deny the possibility that the actual shapes and/or dimensions may be as depicted in the drawings, or that features of the shapes and/or dimensions may be extracted from the drawings. In the description of an embodiment described relatively later, basically, only the differences from relatively previously described embodiments will be describ