A multilayer ceramic electronic component includes an element body formed by alternately stacked internal electrode layers and dielectric layers. The abundance ratio of crystals of the cubic crystal system in grains that form the dielectric layers sandwiched by the internal electrode layers is 25% by mass or higher but no higher than 75% by mass, and the average grain size of the grains that form the dielectric layers sandwiched by the internal electrode layers is 30 nm or larger but no larger than 70 nm. The multilayer ceramic component is intended to maintain a high dielectric constant while offering good DC bias properties.

Provided are a multilayer ceramic capacitor and a method of fabricating the same. The multilayer ceramic capacitor comprises a capacitor body including dielectric layers and internal electrode layers; and an external electrode disposed outside the capacitor body, wherein the dielectric layer includes a plurality of dielectric grains and grain boundaries located between the adjacent dielectric grains, the grain boundary includes a barium titanate-based primary component containing barium (Ba) and titanium (Ti), and inorganic element including silicon (Si), and a standard deviation of atom % of the inorganic element to the total amount of components of the grain boundary is 0.20 to 0.80, and the standard deviation is obtained as the square root of the average of the squares of the deviations.

A dielectric ceramic composition includes main phase grains and a grain boundary between the main phase grains. The main phase grains include a perovskite compound as a main component. The perovskite compound includes at least Ca and Sr as A-site elements and at least Zr and Ti as B-site elements. The dielectric ceramic composition further includes an oxide of at least one additional element. / is 3.0 or more and 6.0 or less, where (unit: parts by mol) denotes a content of the at least one additional element of the dielectric ceramic composition with respect to 100 parts by mol B-site elements, and (unit: parts by mol) denotes a content of the at least one additional element of the grain boundary with respect to 100 parts by mol B-site elements.

A multilayer electronic component includes a body including a dielectric layer and an internal electrode disposed alternately with the dielectric layer, and an external electrode disposed on the body. The internal electrode includes nickel (Ni) and yttrium (Y), and an average thickness of the internal electrode is 50 nm or more to 250 nm or less.

A dielectric composition includes a main phase, first segregation phases, and second segregation phases. The main phase includes a main component having a perovskite crystal structure of ABO.sub.3 (A is one or more selected from Ba, Sr, and Ca, and B is one or more selected from Ti, Zr, and Hf). The first segregation phases include RE (one or more selected from rare earth elements), A, Si, Ti, and O. The second segregation phases include RE, A, Ti, and O and do not substantially include Si. 0.10<S2/S11.50 is satisfied on a cross section of the dielectric composition, where S1 is an area ratio of the first segregation phases, and S2 is an area ratio of the second segregation phases.

Disclosed is a polycrystalline ceramic dielectric comprising: crystal grain bulks made of a barium titanate-based ceramic; and grain boundaries comprising interfaces between the crystal grain bulks, wherein the composition of the grain boundaries is controlled using dopants. By controlling the grain boundary composition using dopants so that the dopants are distributed across a width of 5 nm or less and using a nano-sized, fine-grained barium titanate-based ceramic precursor, the grain boundary structure within the polycrystals may maintain electroneutrality, and their ferroelectricity may be controlled, thereby allowing for smoother polarization reaction. Accordingly, the present disclosure provides polycrystalline ceramic dielectrics that have dielectric properties such as high permittivity and low dielectric losses in a wide frequency range, a small amount of reduction in electric field-dependent relative permittivity, high temperature stability, non-reducibility under a reduction sintering condition, and resulting high insulation resistance, and a preparation method therefor.

A body including a dielectric layer and internal electrodes disposed alternately with the dielectric layer interposed therebetween; and external electrodes disposed on the body, wherein the dielectric layer includes a main component containing calcium (Ca), strontium (Sr), zirconium (Zr) and titanium (Ti) and a sub-component containing manganese (Mn), yttrium (Y) and silicon (Si), wherein the dielectric layer includes a plurality of dielectric grains and grain boundaries disposed between adjacent dielectric grains, and at least a portion of the plurality of dielectric grains has a core-shell structure, a content of yttrium (Y) included in a core relative to 100 moles of zirconium (Zr) included in the core and a shell is defined as Yc, a content of yttrium (Y) included in the shell relative to 100 moles of zirconium (Zr) included in the core and the shell is defined as Ys, and Ys/Yc>9 is satisfied.

A body including a dielectric layer and internal electrodes disposed alternately with the dielectric layer interposed therebetween; and external electrodes disposed on the body, wherein the dielectric layer includes a main component containing calcium (Ca), strontium (Sr), zirconium (Zr) and titanium (Ti) and a sub-component containing manganese (Mn), yttrium (Y) and silicon (Si), wherein the dielectric layer includes a plurality of dielectric grains and grain boundaries disposed between adjacent dielectric grains, and at least a portion of the plurality of dielectric grains has a core-shell structure, a content of yttrium (Y) included in a core relative to 100 moles of zirconium (Zr) included in the core and a shell is defined as Yc, a content of yttrium (Y) included in the shell relative to 100 moles of zirconium (Zr) included in the core and the shell is defined as Ys, and Ys/Yc>9 is satisfied.

A multilayer electronic component includes: a body including a dielectric layer including as a main component one of SrTiO.sub.3 or TiO.sub.2 in which a donor element is substituted for at least one of the element sites excluding the oxygen element (O), and internal electrodes alternately disposed with the dielectric layer in a first direction; and an external electrode disposed on the body; wherein the dielectric layer includes a plurality of dielectric grains, grain boundaries disposed between adjacent dielectric grains, and triple points disposed at a point at which three or more of the grain boundaries contact each other, a first metal oxide disposed at the triple points, and a second metal oxide disposed at the grain boundaries, wherein an atomic percentage of a first metal element included in the first metal oxide may be higher than an atomic percentage of a second metal element included in the second metal oxide.