Dielectric ceramic, method of manufacturing dielectric ceramic, and multilayer ceramic capacitor
AssigneeTaiyo Yuden Co., Ltd.
InventorsYukihiro Konishi, Yusuke Kowase, Kazumichi Hiroi, Kotaro Mizuno, Ayumu Sato
Life of this patent
Estimating the term…
Abstract
A dielectric ceramic whose primary component is an ABO3 compound (A contains Ba and B contains Ti) has a per-layer thickness of approx. 0.5 μm or less, where the volume ratio to all dielectric sintered grains of those whose grain size is in a range of 0.02 μm to 0.15 μm is adjusted to a grain size distribution of 1% to 10%. High dielectric constant and high reliability can be achieved at the same time with the dielectric ceramic.
Claims6
A dielectric ceramic whose primary component is an ABO3 compound (A contains Ba (barium) and B contains Ti (titanium)) and which is constituted by dielectric sintered grains, where a volume ratio to total dielectric sintered grains of those whose grain size is in a range of 0.02 μm to 0.15 μm is 1% to 10%.
A method of manufacturing a dielectric ceramic, comprising:
- preparing dielectric green sheets by adding an auxiliary component of 0.1 μm or less in grain size to a material powder for primary component constituted by an ABO3 compound (A contains Ba (barium) and B contains Ti (titanium)) and having a grain size of 0.05 μm to 0.12 μm;
- and
- sintering the dielectric green sheets so that a volume ratio to total dielectric sintered grains of those whose grain size is in a range of 0.02 μm to 0.15 μm becomes 1% to 10%.
A multilayer ceramic capacitor formed by alternately stacking dielectric layers constituted by dielectric sintered grains, and electrode layers, wherein:
- a thickness of each dielectric layer is 0.5 μm or less;
- and
- a primary component of the dielectric layer is an ABO3 compound (A contains Ba (barium) and B contains Ti (titanium)) and a volume ratio to total dielectric sintered grains of those whose grain size is in a range of 0.02 μm to 0.15 μm is 1% to 10%.
Dependencies are inferred from the claim text.