Dielectric powder, multilayer ceramic electronic device, manufacturing method of dielectric powder and manufacturing method of multilayer ceramic electronic device

A multilayer ceramic electronic device comprising:

• a plurality of dielectric layers that includes a core-shell grain including a core portion and a shell portion including an additive, the core portion has a structure, in which barium titanate is a main component, at least one type of rare earth element is solid-solved at 0.3 at % or more and 2.0 at % or less with respect to titanium, and magnesium is solid-solved at 0.1 at % or more and 1.0 at % or less with respect to titanium;
• a plurality of internal electrode layers, each of which faces each other through each of the plurality of dielectric layers;
• a first external electrode that is electrically connected to part of the plurality of internal electrode layers;
• and
• a second external electrode is electrically connected to another part of the plurality of internal electrode layers.

A manufacturing method of a dielectric powder comprising:

• mixing at least one type of rare earth element, magnesium, barium compound and titanium compound so that an amount of the at least one type of rare earth element is 0.3 at % or more and 2.0 at % or less with respect to titanium and an amount of magnesium is 0.1 at % or more and 1.0 at % or less with respect to titanium;
• forming slurry of which a main component is barium titanate, by solid phase reaction of the at least one type of rare earth element, the magnesium, the barium compound and the titanium compound;
• and
• solid-solving the at least one type of rare earth element in the barium titanate by thermal treatment of the slurry.

A manufacturing method of a multilayer ceramic electronic device comprising:

• forming a ceramic green sheet by adding an additive to a dielectric powder, in which barium titanate is a main component, at least one type of rare earth element is solid-solved at 0.3 at % or more and 2.0 at % or less with respect to titanium, and magnesium is solid-solved at 0.1 at % or more and 1.0 at % or less with respect to titanium;
• forming an internal electrode pattern on the ceramic green sheet;
• forming a multilayer structure by stacking a plurality of the ceramic green sheet on which the internal electrode pattern is formed;
• and
• forming a multilayer chip by firing the multilayer structure so that the multilayer chip includes a plurality of dielectric layers that include a core-shell grain including a core portion and a shell portion including an additive, the core portion having a structure, in which barium titanate is a main component, at least one type of rare earth element is solid-solved at 0.3 at % or more and 2.0 at % or less with respect to titanium, magnesium is solid-solved at 0.1 at % or more and 1.0 at % or less with respect to titanium, and a plurality of internal electrode layers, each of which faces each other through each of the plurality of dielectric layers.