Capacitor and module

Patent metadata

Field	Value
Publication number	US-2018012702-A1
Application number	US-201615544136-A
Country	US
Kind code	A1
Filing date	Jan 26, 2016
Priority date	Jan 29, 2015
Publication date	Jan 11, 2018
Grant date	—

Abstract

The capacitor includes a dielectric body portion including ceramic layers and internal-electrode layers laminated in an alternating manner, and a cover portion provided in a periphery of the dielectric body portion. The cover portion includes pores. A part of the cover portion located in a position in a direction perpendicular to a lamination direction of the ceramic layers and the internal-electrode layers is a side surface cover portion. When the side surface cover portion is divided into three equal regions in a width direction, the regions being a dielectric body portion-side region, a central region, and a surface-side region, the number of the pores is higher in the dielectric body portion-side region than in the central region and the surface-side region.

First claim

1 . A capacitor comprising:
a dielectric body portion comprising ceramic layers and internal-electrode layers laminated in an alternating manner; and a cover portion provided in a periphery of the dielectric body portion, wherein the cover portion comprises pores; a part of the cover portion located in a position in a direction perpendicular to a lamination direction of the ceramic layers and the internal-electrode layers is a side surface cover portion; and when the side surface cover portion is divided into three equal regions in a width direction, the regions being a dielectric body portion-side region, a central region, and a surface-side region, the number of the pores is higher in the dielectric body portion-side region than in the central region and the surface-side region.

2 . The capacitor according to claim 1 , wherein the number of the pores gradually increases from the surface-side region toward the dielectric body portion-side region.

3 . The capacitor according to claim 1 , wherein an average diameter of the pores is greater in the dielectric body portion-side region than in the surface-side region.

4 . The capacitor according to claim 1 , wherein when the dielectric body portion is divided into two equal parts in the lamination direction, the number of the pores in the side surface cover portion differs between a top surface side and a bottom surface side.

5 . The capacitor according to claim 4 , wherein when two parts of the cover portion located on a top surface side and a bottom surface side of the dielectric body portion in the lamination direction are each taken as an outer layer cover portion, the number of the pores differs between the two outer layer cover portions; and an outer layer cover portion of the two outer layer cover portions, the outer layer cover portion having a higher number of the pores, is located on a side where the side surface cover portion having a higher number of the pores is located.

6 . The capacitor according to claim 5 , wherein a ceramic layer of the ceramic layers disposed on a side where the outer layer cover portion having a higher number of pores is located is thicker than a ceramic layer of the ceramic layers disposed on a side where an outer layer cover portion of the two outer layer cover portions, the outer layer cover portion having a lower number of pores, is located.

7 . The capacitor according to claim 5 , wherein an internal-electrode layer of the internal-electrode layers disposed on the side where the outer layer cover portion having a higher number of pores is located has a lower continuity than an internal-electrode layer of the internal-electrode layers disposed on the side where the outer layer cover portion having a lower number of pores is located.

8 . The capacitor according to claim 5 , further comprising:
a pair of external electrodes opposing each other in a direction perpendicular to the lamination direction of the ceramic layers and the internal-electrode layers, wherein the outer layer cover portion having a higher number of the pores is longer, in the direction in which the external electrodes oppose each other, than the outer layer cover portion having a lower number of the pores.

9 . The capacitor according to claim 5 , wherein the outer layer cover portion having a higher number of the pores is longer, in a direction perpendicular to a direction in which the external electrodes oppose each other, than the outer layer cover portion having a lower number of the pores.

10 . A module comprising a capacitor mounted on a surface of a wiring board,
wherein the capacitor is the capacitor according to claim 1 .

Assignees

• Kyocera Corp

Inventors

• Azuma Yusuke
• Seki Hidenobu

Classifications

• H05K2201/10015

  Non-printed capacitor · CPC title

• H05K1/181

  associated with surface mounted components · CPC title

• H01G4/30 Primary

  Stacked capacitors (H01G4/33 takes precedence) · CPC title

• H01G4/248

  the terminals embracing or surrounding the capacitive element, e.g. caps (H01G4/252 takes precedence) · CPC title

• H01G4/1209

  characterised by the ceramic dielectric material (H01G4/1272, H01G4/1281 take precedence) · CPC title