MULTILAYER CERAMIC CAPACITOR
The present invention relates to a multilayer ceramic capacitor which is superior in stability of temperature characteristic of specific permittivity and has a high specific permittivity and a high reliability. Said multilayer ceramic capacitor is characterized in that the dielectric layers include BTZ based dielectric ceramic composition, in which Ti is substituted by 1 to 8 mol % of Zr with respect to Ti, as a main component, dielectric particles constituting the BTZ based dielectric ceramic composition substantially do not have shell structures, and Curie temperature of the BTZ based dielectric ceramic composition is higher than a temperature range of the multilayer ceramic capacitor used.
1 . A multilayer ceramic capacitor in which dielectric layers and internal electrode layers are alternately stacked, wherein
the dielectric layers include BTZ based dielectric ceramic composition, in which Ti is substituted by 1 to 8 mol % of Zr with respect to Ti, as a main component
dielectric particles constituting the BTZ based dielectric ceramic composition substantially do not have shell structures, and
Curie temperature of the BTZ based dielectric ceramic composition is higher than a temperature range of the multilayer ceramic capacitor used.
2 . The multilayer ceramic capacitor as set forth in claim 1 , wherein Curie temperature Tc of the BTZ based dielectric ceramic composition is 85° C.≦Tc≦110° C.
3 . The multilayer ceramic capacitor as set forth in claim 1 , wherein thickness of the dielectric layer is 3 μm or less.
4 . The multilayer ceramic capacitor as set forth in claim 2 , wherein thickness of the dielectric layer is 3 μm or less.
5 . The multilayer ceramic capacitor as set forth in claim 1 , wherein capacitance change rate to temperature is 15% or less at −55 to 85° C., which is the temperature range of multilayer ceramic capacitor used.
6 . The multilayer ceramic capacitor as set forth in claim 2 , wherein capacitance change rate to temperature is 15% or less at −55 to 85° C., which is the temperature range of multilayer ceramic capacitor used.
7 . The multilayer ceramic capacitor as set forth in claim 1 , wherein the BTZ based dielectric ceramic composition is dielectric oxide shown by a general formula (Ba 1-x Ca x ) m (Ti 1-y Zr y )O 3 where 0≦x≦0.06, 0.01≦y≦0.08 and 0.950≦m≦1.050.
8 . The multilayer ceramic capacitor as set forth in claim 2 , wherein the BTZ based dielectric ceramic composition is dielectric oxide shown by a general formula (Ba 1-x Ca x ) m (Ti 1-y Zr y )O 3 where 0≦x≦0.06, 0.01≦y≦0.08 and 0.950≦m≦1.050.