Taiyo Yuden Co., Ltd.

Mitsubishi Electric Corporation

Katsuya Taniguchi

Koichiro Morita

Minoru Ryu

Yoshiki Iwazaki

Tsuyoshi Sogabe

Kotaro Mizuno

Chie Kawamura

Jun Nishikawa

Yukihiro Konishi

Yusuke Kowase

Tetsuo Shimura

Koji Ota

Shohei Kitamura

Kazumichi Hiroi

Yuichi Kasuya

Akane Nomura

Takehiro Koyano

Masaki Kondo

Naohiro Ichikawa

A multilayer ceramic electronic device includes a multilayer chip. The multilayer chip has a capacity section and a side margin. The side margin includes boron and silicon, and includes a first section and a second section in order from the capacity section side toward outside. A boron concentration of the first section is larger than a boron concentration of the second section. A segregation degree of silicon in the second section is larger than a segregation degree of silicon in the first section.

Multilayer ceramic electronic device and manufacturing method of the same

A ceramic electronic device includes: a multilayer structure; and a cover layer, wherein a concentration of Mn of the cover layer with respect to a main component ceramic is larger than a concentration of Mn of the dielectric layers with respect to a main component ceramic in a capacity section, wherein an average crystal grain diameter of a first dielectric layer is smaller than that of a second dielectric layer, and a concentration of Mn of the first dielectric layer with respect to the main component ceramic is larger than a concentration of Mn of the second dielectric layer with respect to the main component ceramic, in the capacity section.

Ceramic electronic device and manufacturing method of the same

A selection method includes: obtaining or providing multilayer ceramic capacitors each having a multilayer structure in which each of a plurality of ceramic dielectric layers and each of a plurality of internal electrode layers are alternately stacked; measuring a ratio of (a current value at 10 V/μm when a direct voltage is applied to a plurality of ceramic dielectric layers at 125 degrees C.)/(a current value at 10 V/μm when a direct voltage is applied to the plurality of the ceramic dielectric layers at 85 degrees C.), with respect to each multilayer ceramic capacitor; determining whether the ratio is in a predetermined range; and selecting a multilayer ceramic capacitor or multilayer ceramic capacitors each having a ratio in the predetermined range as a desired multilayer ceramic capacitor.

Method for selecting multilayer ceramic capacitor

A multilayer ceramic capacitor includes: a multilayer structure in which dielectric layers and internal electrode layers are alternately stacked; wherein a main component of the dielectric layers is a ceramic material having a main phase having a perovskite structure (ABO) wherein a B site includes an element solid-solved in the B site and acting as a donor; wherein an A site and the B site of the ceramic material includes a rare earth element, wherein (an amount of the rare earth element substitutionally solid-solved in the A site)/(an amount of the rare earth element substitutionally solid-solved in the B site) is 0.75 or more and 1.25 or less. The amount of the element acting as the donor in the B site is 0.05 to 0.3 atm % relative to a main component element of the B site.

Multilayer ceramic capacitor and ceramic material powder

Ceramic raw material powder includes: a main phase having a perovskite structure, wherein elements acting as a donor and an acceptor are solid-solved in B sites of the perovskite structure, wherein a first relationship of value A&#x3c;value B is satisfied in a center region of each grain of the ceramic raw material powder; a second relationship of value A&#x3e;value B is satisfied in a circumference region of each grain of the ceramic raw material powder, and value A in the second relationship gradually decreases from the circumference region to the center, wherein value A is a value of (concentration of the element acting as a donor)&#xd7;(valence of the element acting as a donor&#x2212;4), and value B is a value of (concentration of the element acting as an acceptor)&#xd7;(4&#x2212;valence of the element acting as an acceptor).

Ceramic raw material powder, multilayer ceramic capacitor and manufacturing method of multilayer ceramic capacitor

An airtightness evaluation device includes a differential pressure gauge to output a pressure difference between two spaces connected to two joints. A system joint for connecting a refrigeration cycle system is connected to one joint of the differential pressure gauge. A pressure vessel is connected to the other joint of the differential pressure gauge. The airtightness evaluation device includes a bypass circuit to connect the system joint and the pressure vessel to each other with bypassing the differential pressure gauge, and a bypass valve to open/close the bypass circuit. The airtightness evaluation device also includes a supply source joint for supplying a pressurization gas to the pressure vessel.

Airtightness evaluation device

A multilayer ceramic capacitor includes: a multilayer structure in which each of a plurality of dielectric layers and each of a plurality of internal electrode layers are alternately stacked, wherein a concentration of a rare earth element in an active region with respect to a main component ceramic of the active region is equal to or more than a concentration of a rare earth element in at least a part of a protective region with respect to a main component ceramic of the protective region, wherein an average ionic radius of the rare earth element of the at least a part of the protective region is equal to or less than an average ionic radius of the rare earth element in the active region.

Multilayer ceramic capacitor having controlled concentration of rare earth element

Multilayer ceramic capacitor and manufacturing method of multilayer ceramic capacitor

Ceramic raw material powder includes: a main phase having a perovskite structure, wherein elements acting as a donor and an acceptor are solid-solved in B sites of the perovskite structure, wherein a relationship of (concentration of the element acting as a donor)&#xd7;(valence of the element acting as a donor&#x2212;4)&#x3c;(concentration of the element acting as an acceptor)&#xd7;(4&#x2212;valence of the element acting as an acceptor) is satisfied, in a center region of each grain of the ceramic raw material powder, wherein a relationship of (concentration of the element acting as a donor)&#xd7;(valence of the element acting as a donor&#x2212;4)&#x3e;(concentration of the element acting as an acceptor)&#xd7;(4&#x2212;valence of the element acting as an acceptor) is satisfied, in a circumference region of each grain of the ceramic raw material powder.

A multilayer ceramic capacitor includes: a multilayer structure in which each of a plurality of dielectric layers and each of internal electrode layers are alternately stacked; wherein a main component of the dielectric layers is a ceramic material, wherein a main phase of the ceramic material has a perovskite structure expressed by a general formula ABO, wherein a B site of the ceramic material includes an element acting as a donor; wherein an A site and the B site of the ceramic material includes a rare earth element, wherein (an amount of the rare earth element substitutionally solid-solved in the A site)/(an amount of the rare earth element substitutionally solid-solved in the B site) is 0.75 or more and 1.25 or less.

A multilayer ceramic capacitor includes: a pair of external electrodes; a first internal electrode containing a base metal and coupled to one of the pair 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 external electrodes, wherein 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, is within &#xb1;20% of an average of the concentrations of the base metal in the five regions, and thicknesses of the first internal electrode and the second internal electrode are 0.2 &#x3bc;m or greater.

Multilayer ceramic capacitor

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 the base metal and a ceramic material mainly composed of barium titanate; and a second internal electrode stacked on the dielectric layer, containing the base metal, and coupled to another one of the external electrodes, wherein a concentration of the base metal in each of five regions, which are equally divided regions between locations 50 nm away from the first and second internal electrodes in a stacking direction between the first and second internal electrodes, is within &#xb1;20% of an average of the concentrations of the base metal in the five regions, and an atomic concentration ratio of Mg to Ti is 0 or greater and less than 0.002 in the dielectric layer.

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 external electrodes, wherein 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, is within &#xb1;20% of an average of the concentrations of the base metal in the five regions, and an average grain size in the dielectric layer is 200 nm or less.

A multilayer ceramic capacitor includes: a pair of external electrodes; a first internal electrode that is coupled to one of the pair of external electrodes; a dielectric layer that is stacked on the first internal electrode and contains BaTiOand Ni; and a second internal electrode that is stacked on the dielectric layer, contains Ni, and is coupled to another one of the pair of external electrodes, wherein Ni is contained in five regions, which are equally divided region 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, and a Ni concentration in at least one of end regions located closest to the first internal electrode and the second internal electrode among the five regions is greater than a Ni concentration in a central region of the five regions by 10% or more.

Mutilayer ceramic capacitor with dielectric layers containing nickel

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 external electrodes, wherein a concentration of the base metal in each of five regions is within &#xb1;20% of an average of the concentrations of the base metal in the five regions, the five regions being obtained by dividing a region from a location 50 nm away from the first internal electrode of the dielectric layer to a location 50 nm away from the second internal electrode of the dielectric layer in a stacking direction between the first and second internal electrodes equally into five.

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Takasaki, Japan

Katsuya Taniguchi