Murata Manufacturing Co., Ltd.

Kazuhisa Uchida

Jun Ikeda

Akito Mori

Yoshito Saito

Akihiro Tsuru

Yoshiyuki Abe

Takehisa Sasabayashi

Akitaka Doi

Naoto Muranishi

Yukie Watanabe

Hideyuki Hashimoto

Shinya Isota

Yuta Oshima

Natsuko Okubo

A multilayer ceramic capacitor includes a multilayer body including dielectric layers and internal electrode layers, and external electrodes. The multilayer body includes side margin portions made of a dielectric. In the internal electrode layers, a width of an extension electrode portion is smaller than a width of a counter electrode portion. The side margin portions each include Ba and Ti as a main component and Mg as a sub component. The Mg content is about 0.2 mol % or more and about 2.0 mol % or less with respect to 100 mol of Ti. The internal electrode layers each include Ni as a main component, and an end portion of the counter electrode portion includes Mg as a sub component. The Mg content is about 0.13 mol % or more and about 0.39 mol % or less with respect to 100 mol of Ni.

Multilayer ceramic capacitor

A multilayer ceramic capacitor includes a multilayer body including the dielectric ceramic layers and the internal electrode layers which are laminated, and external electrodes connected to the internal electrode layers. The multilayer body includes segregation including Si as a main component in a vicinity of an end of the internal electrode layer in a width direction. An average particle size of the dielectric particles in the vicinity of the end of the internal electrode layer in the width direction in the dielectric ceramic layer is smaller than an average particle size of a dielectric particles in a central portion of the internal electrode layer in the width direction in the dielectric ceramic layer.

A multilayer ceramic capacitor includes first dielectric ceramic layers each with a thickness of about 0.48 μm or more and about 0.50 μm or less in the lamination direction, and additional dielectric ceramic layers each with a thickness of about 10 μm or more and about 15 μm or less in the width direction. A number of dielectric particles in each first dielectric ceramic layer in a thickness direction is three or more and six or less. A number of dielectric particles in each additional dielectric ceramic layer in a thickness direction is 100 or more and 150 or less. When the number of dielectric particles in each of first dielectric ceramic layer is N, and the number of dielectric particles in each additional dielectric ceramic layer is N, a ratio of Nto Nis about 1:23.08 or more and about 1:46.15 or less.

A multilayer ceramic capacitor that includes a ceramic body including a stack of a plurality of dielectric layers and a plurality of first and second internal electrodes; and first and second external electrodes provided at each of both end faces of the ceramic body. Each of the plurality of dielectric layers contain Ba, Ti, P and Si. The plurality of dielectric layers include an outer dielectric layer located on an outermost side in the stacking direction; an inner dielectric layer located between the first and second internal electrodes; and a side margin portion in a region where the first and second internal electrodes do not exist. In at least one of the outer dielectric layer, the inner dielectric layer and the side margin portion, the P and the Si segregate in at least one of grain-boundary triple points of three ceramic particles.

A multilayer ceramic capacitor includes a multilayer body including dielectric ceramic layers and internal electrode layers laminated alternately in a lamination direction, and a pair of external electrodes on both end portions in the length direction of the multilayer body and respectively connected to the internal electrode layers. The pair of external electrodes each include a base region covering at least each of the first and second end surfaces, connected to the internal electrode layers, and including Cu as a main component, a cover region on the base region to cover the base region, and including Ag as a main component, and a reaction region between the base region and the cover region including Cu included in the base region and Ag included in the cover region reacting with each other.

A multilayer ceramic capacitor includes a base body including first and second main surfaces, first and second side surfaces, first and second end surfaces, and dielectric layers and internal electrode layers, and external electrodes at the first and second end surfaces, and electrically connected to the internal electrode layers. The base body includes an inner layer, first and second outer layers, first and second side margin portions. The dielectric layers in the inner layer and the first and second outer layers include main crystal grains including barium and titanium, and with respect to 100 parts by mol of titanium, nickel in an amount of about 0.2 to about 3.0 parts by mol, and at least one rare earth element selected from yttrium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium in an amount of about 0.6 parts to about 2.0 parts by mol.

A multilayer ceramic capacitor includes first dielectric ceramic layers each with a thickness of about 0.48 &#x3bc;m or more and about 0.50 &#x3bc;m or less in the lamination direction, and additional dielectric ceramic layers each with a thickness of about 10 &#x3bc;m or more and about 15 &#x3bc;m or less in the width direction. A number of dielectric particles in each first dielectric ceramic layer in a thickness direction is three or more and six or less. A number of dielectric particles in each additional dielectric ceramic layer in a thickness direction is 100 or more and 150 or less. When the number of dielectric particles in each of first dielectric ceramic layer is N, and the number of dielectric particles in each additional dielectric ceramic layer is N, a ratio of Nto Nis about 1:23.08 or more and about 1:46.15 or less.

A multilayer ceramic capacitor includes a laminate including a dielectric ceramic layer and first and second electrode layers laminated in a lamination direction, and first and second external electrodes respectively connected to the first and second internal electrode layers. The laminate includes a central layer portion, a peripheral layer portion sandwiching the central layer portion, and a side margin sandwiching the central layer portion and the peripheral layer portion. The first and second internal electrode layers and the first and second external electrodes include Ni. In a cross section including the lamination direction and a width direction, a Ni content of the peripheral layer portion is larger at a surface portion than at a central portion in a thickness direction, and a Ni content of the side margin is larger at a surface portion than at a central portion in a thickness direction of the side margin.

A multilayer ceramic capacitor includes a laminate including a dielectric ceramic layer and first and second internal electrode layers laminated in a lamination direction, and first and second external electrode connected to the internal electrode layers. The laminate includes a central layer portion, a peripheral layer portion sandwiching the central layer portion, and a side margin sandwiching the central layer portion and the peripheral layer portion. The side margin includes an inner layer and an outer layer. In a cross section including a lamination direction and a width direction obtained by cutting the laminate at the center in a longitudinal direction of the laminate, the ceramic grains in the dielectric ceramic layer between ends of the internal electrode layers in the width direction have a smaller diameter than the ceramic grains in the dielectric ceramic layer at the center of the central layer portion in the width direction.

A multilayer ceramic capacitor that includes outer electrodes and a multilayer body having stacked inner electrode layers and dielectric layers. The dielectric layers in an effective section contain, relative to 100 parts by mole of Ti, 0.7 to 1.2 parts by mole of Si, 0.9 to 1.1 parts by mole of Dy, 0.24 to 0.34 parts by mole of Mg, 0.17 to 0.23 parts by mole of Al, 0.09 to 0.11 parts by mole of Mn, and 0.04 to 0.06 parts by mole of V. The dielectric layers have a Ba/Ti molar ratio of 1.0073 to 1.0083.

In a monolithic ceramic capacitor, ceramic layers defining inner layers are mainly composed of a perovskite compound containing Ba and Ti. A portion of an electrically effective section in the ceramic layers near a connecting portion between the inner electrodes and an outer electrode undergoes mapping analysis by an energy-dispersive method. In regions of the resulting mapping image, the regions extending from the interfaces between the inner electrodes and a corresponding one of the ceramic layers to positions about &#x2153; of the thickness of the ceramic layer in the stacking direction, ((L2&#x2212;L3)/L1)&#xd7;100&#x2267;50 is satisfied, where L1 represents the total length of grain boundaries, L2 represents the total length of grain boundaries where a rare-earth element is present, and L3 represents the total length of portions where the grain boundaries where the rare-earth element is present are overlapped with grain boundaries with a specific element present.

Monolithic ceramic capacitor containing perovskite compound

In a multilayer ceramic capacitor, an inner ceramic layer includes a perovskite-type compound containing Ba and Ti. A region within an electrically effective portion of the inner ceramic layers sandwiched between inner electrodes, which is near an area where inner and outer electrodes connect to each other, is subjected to a mapping analysis using EDS. ((L&#x2212;L)/L)&#xd7;100&#x2267;50 is satisfied, Ldenotes a total length of ceramic grain boundaries detected from a TEM transmission image, Ldenotes a total length of grain boundaries, detected from a mapping image and the TEM transmission image, where the rare earth element is present, and Ldenotes a total length of portions, detected from a mapping image and the TEM transmission image, in which the grain boundaries where the rare earth element is present and grain boundaries where at least one of Mn, Mg, and Si is present are overlapped.

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Nagaokakyo, Japan

Kazuhisa Uchida