Multilayer ceramic capacitor

Patent metadata

Field	Value
Publication number	US-9478358-B2
Application number	US-201514732849-A
Country	US
Kind code	B2
Filing date	Jun 8, 2015
Priority date	Jun 12, 2014
Publication date	Oct 25, 2016
Grant date	Oct 25, 2016

Abstract

A multilayer ceramic capacitor that includes dielectric layers made mainly of a perovskite compound containing Ba and Ti and optionally Zr and Hf, and inner electrodes having an average thickness of approximately 0.5 μm or less. The Mg content of the dielectric layers is approximately in the range of 0≦Mg≦0.4 (parts by mole) based on a total of 100 parts by mole of Ti, Zr, and Hf. The proportion of Mg-containing defects in the inner electrodes is approximately 20% or more.

First claim

What is claimed is:

1. A multilayer ceramic capacitor comprising:
a plurality of dielectric layers containing a perovskite compound containing Ba and Ti; and
a plurality of inner electrodes containing Ni as an electroconductive material and a common material, each inner electrode of the plurality of inner electrodes being located in a respective interface between adjacent dielectric layers of the plurality of dielectric layers, wherein
an average thickness of the inner electrodes is 0.5 μm or less,
a first Mg content of the dielectric layers is in a range of 0 parts by mole≦Mg≦0.4 parts by mole based on a total of 100 parts by mole of Ti in the dielectric layers,
a second Mg content in the common material of the inner electrodes is in a range of 1 to 5 parts by mole based on a total of 100 parts by mole of Ti in the inner electrodes, and
Mg is present in defects defined by regions where an inner electrode is discontinuous, a proportion thereof is expressed as follows:
the number of the defects in which the Mg is present/the total number of the defects×100%≧approximately 20%.

2. The multilayer ceramic capacitor according to claim 1 , wherein the perovskite compound further contains Zr and Hf, and
the Mg content of the dielectric layers is in a range of 0 parts by mole≦Mg≦0.4 parts by mole based on a total of 100 parts by mole of Ti, Zr, and Hf.

3. The multilayer ceramic capacitor according to claim 1 , wherein adjacent inner electrodes respectively extend to opposite end faces of the multilayer ceramic capacitor.

4. The multilayer ceramic capacitor according to claim 3 , further comprising an outer electrode on each end face of the multilayer ceramic capacitor and coupled to the inner electrodes extended thereto.

5. The multilayer ceramic capacitor according to claim 1 , wherein the Ti content of the common material is 3 parts by mole to 100 parts by mole of Ni in the inner electrodes.

Assignees

• Murata Manufacturing Co

Inventors

• Kanzaki Taisuke
• Masunari Akio

Classifications

• C04B2235/3206

  Magnesium oxides or oxide-forming salts thereof · CPC title

• C04B35/4682

  based on BaTiO3 perovskite phase · CPC title

• C04B2237/346

  Titania or titanates · CPC title

• C04B2235/3239

  Vanadium oxides, vanadates or oxide forming salts thereof, e.g. magnesium vanadate · CPC title

• C04B2235/3267

  MnO2 · CPC title