Multilayer ceramic electronic component including plating material of external terminal electrode disposed in voids of inner conductor and method for manufacturing the same

• US 8,310,805 B2
• Filed: 06/10/2009
• Issued: 11/13/2012
• Est. Priority Date: 06/11/2008
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Tashima, Takeshi, Matsumoto, Hiroyuki
• Primary Examiner(s): Sinclair, David M
• Application Number:
  US12/481,694
• Publication Number:
  US 20090310276A1
• Time in Patent Office: 1,252 Days
• Field of Search: 361/321.2, 361/303
• US Class Current: 361/303
• CPC Class Codes: H01G 4/012 Form of non-self-supporting electrodes
• CPC Class Codes: H01G 4/232 electrically connecting two or more layers of a stacked or rolled capacitor
• CPC Class Codes: H01G 4/2325 characterised by the material of the terminals
• CPC Class Codes: H01G 4/30 Stacked capacitors H01G4/33 takes precedence
• CPC Class Codes: Y10T 29/435 Solid dielectric type

Abstract

A multilayer ceramic electronic component includes external terminal electrodes that are formed by direct plating on the first and second side surfaces of a ceramic body including stacked ceramic layers and inner conductors. The external terminal electrodes include base plating films formed so as to cover the exposed portions of inner conductors. Voids are provided that are open to the side surfaces of the ceramic body so as to be adjacent to the ends in the width direction of the exposed portions of the inner conductors. A plating metal defining the base plating films enters the voids and is electrically connected to the inner conductors in the ceramic body.

Claims

1. A multilayer ceramic electronic component comprising:

a ceramic body including a first principal surface and a second principal surface opposing each other, a first side surface and a second side surface opposing each other and connecting the first principal surface to the second principal surface and a third side surface and a fourth side surface opposing each other and connecting the first principal surface to the second principal surface and the ceramic body including a plurality of stacked ceramic layers;

an inner conductor provided in the ceramic body, the inner conductor including an exposed portion having a width on at least the first side surface; and

an external terminal electrode provided on at least the first side surface, the external terminal electrode being electrically connected to the inner conductor;

wherein

the external terminal electrode includes a base plating film that is directly plated on at least the first side surface so as to directly contact and cover the exposed portion of the inner conductor;

voids are provided in a discontinuous manner at a periphery of the inner conductor at which the inner conductor contacts a respective one of the plurality of stacked ceramic layers;

at least one of the voids is open to at least the first side surface of the ceramic body;

the at least one of the voids is arranged adjacent to the exposed portion of the inner conductor in a direction connecting the third side surface to the fourth side surface; and

a plating metal defining the base plating film is disposed in the at least one of the voids that is open to at least the first side surface of the ceramic body, is not disposed in any of the voids other than the at least one of the voids that is open to at least the first side surface of the ceramic body, and is electrically connected to the inner conductor in the ceramic body.

2. A method for manufacturing a multilayer ceramic electronic component including a ceramic body including a first principal surface and a second principal surface opposing each other, a first side surface and a second side surface opposing each other and connecting the first principal surface to the second principal surface and a third side surface and a fourth side surface opposing each other and connecting the first principal surface to the second principal surface and formed by stacking a plurality of ceramic layers, a plurality of inner conductors that are formed in the ceramic body, portions of the plurality of inner conductors being exposed on at least the first side surface of the ceramic body, which are exposed portions, and an external terminal electrode formed on at least the first side surface of the ceramic body so as to be electrically connected to the plurality of inner conductors and to cover the exposed portions of the plurality of inner conductors, comprising the steps of:

forming the ceramic body including the plurality of inner conductors arranged so as to face each other through respective ones of the plurality of ceramic layers and including voids formed in a discontinuous manner at peripheries of the plurality of inner conductors at which the plurality of inner conductors contact the respective ones of the plurality of ceramic layers, at least one of the voids being open to at least the first side surface of the ceramic body, the at least one of the voids being arranged adjacent to the exposed portion of at least one of the plurality of inner conductors in a direction connecting the third side surface to the fourth side surface; and

forming a base plating film on at least the first side surface of the ceramic body by direct plating in a step of forming the external terminal electrode on the ceramic body, such that the base plating film directly contacts and covers the exposed portions of the plurality of inner conductors and a plating metal defining the base plating film enters the at least one of the voids that is open to at least the first side surface of the ceramic body, does not enter any of the voids other than the at least one of the voids that is open to at least the first side surface of the ceramic body, and is electrically connected to the plurality of inner conductors in the ceramic body.

3. The method for manufacturing a multilayer ceramic electronic component according to claim 2, wherein, in the step of forming the ceramic body, the voids are formed when a green ceramic body is fired.