Multilayer ceramic capacitor with dielectric layers containing base metal

Patent metadata

Field	Value
Publication number	US-10147546-B2
Application number	US-201715457060-A
Country	US
Kind code	B2
Filing date	Mar 13, 2017
Priority date	Jun 20, 2016
Publication date	Dec 4, 2018
Grant date	Dec 4, 2018

Abstract

A multilayer ceramic capacitor includes: a pair of external electrodes; a first internal electrode containing a base metal and coupled to one of the external electrodes; a dielectric layer stacked on the first internal electrode and containing a ceramic material and the base metal; and a second internal electrode stacked on the dielectric layer, containing the base metal, and coupled to another one of the pair external electrodes, a concentration of the base metal in each of five regions, which are equally divided regions of a region between locations 50 nm away from the first and second internal electrodes in a stacking direction between the first and second internal electrodes, being within ±20% of an average of the concentrations of the base metal in the five regions, an average grain number in the dielectric layer being three or less in the stacking direction between the first and second internal electrodes.

First claim

What is claimed is:

1. A multilayer ceramic capacitor comprising:
a pair of external electrodes;
a first internal electrode that contains nickel and is coupled to one of the pair of external electrodes;
a dielectric layer that is stacked on the first internal electrode and contains a ceramic material and nickel, the ceramic material including barium and titanium; and
a second internal electrode that is stacked on the dielectric layer, contains nickel, and is coupled to another one of the pair of external electrodes, wherein
a concentration of nickel in each of five regions is within ±20% of an average of the concentrations of nickel in the five regions, the concentration of nickel being an atomic concentration ratio of nickel to barium and titanium, the five regions being obtained by dividing a region of the dielectric layer equally into five in a stacking direction, the region of the dielectric layer being located from a location 50 nm away from the first internal electrode to a location 50 nm away from the second internal electrode in the stacking direction between the first internal electrode and the second internal electrode,
an average number of grains in the dielectric layer is three or less in the stacking direction between the first internal electrode and the second internal electrode, and
the region located from the location 50 nm away from the first internal electrode to the location 50 nm away from the second internal electrode includes both a crystal grain of the ceramic material and a crystal grain boundary of the crystal grain.

2. The multilayer ceramic capacitor according to claim 1 , wherein
the concentration of nickel in each of the five regions is within ±10% of the average of the concentrations of nickel in the five regions.

3. The multilayer ceramic capacitor according to claim 1 , wherein
the concentration of nickel in each of the five regions is within ±5% of the average of the concentrations of nickel in the five regions.

4. The multilayer ceramic capacitor according to claim 1 , wherein
the ceramic material is BaTiO 3 , and
the dielectric layer has a composition in which a ratio of a total molar concentration of one or more of Y, Dy, and Ho to a molar concentration of Ti is 0.01 or greater.

5. The multilayer ceramic capacitor according to claim 1 , wherein
the dielectric layer has a thickness of 0.6 μm or less.

6. The multilayer ceramic capacitor according to claim 1 , wherein
the multilayer ceramic capacitor comprises two or more of the dielectric layer as first dielectric layers and zero or more of a second dielectric layer that is different from the first dielectric layers, and
80% or more of dielectric layers of the multilayer ceramic capacitor are the first dielectric layers.

7. The multilayer ceramic capacitor according to claim 1 , wherein the concentration of nickel is measured by TEM (Transmission Electron Microscope).

Assignees

• Taiyo Yuden Kk

Inventors

• Morita Koichiro
• Taniguchi Katsuya
• Ryu Minoru
• Iwazaki Yoshiki

Classifications

• H01G4/012

  Form of non-self-supporting electrodes · CPC title

• H01G4/0085

  Fried electrodes · CPC title

• H01G4/2325

  characterised by the material of the terminals · CPC title

• H01G4/1227 Primary

  based on alkaline earth titanates · CPC title

• H01G4/30 Primary

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