X8R dielectric composition for use with nickel electrodes
Multilayer ceramic chip capacitors which satisfy X8R requirements and which are compatible with reducing atmosphere sintering conditions so that non-noble metals such as nickel and nickel alloys thereof may be used for internal and external electrodes are made in accordance with the invention. The capacitors exhibit desirable dielectric properties (high capacitance, low dissipation factor, high insulation resistance), excellent performance on highly accelerated life testing, and very good resistance to dielectric breakdown. The dielectric layers comprise a barium titanate base material doped with other metal oxides such as BaO, Y 2 O 3 , ZrO 2 , SiO 2 , MgO, MnO, MoO 3 , CaO, Lu 2 O 3 , Yb 2 O 3 , or WO 3 in various combinations.
1. A powder composition for use in forming a dielectric material for use in a multilayer ceramic chip capacitor comprising, prior to sintering, a blend of:
a. BaTiO 3 , and the following, per 100 mole parts of BaTiO 3 :
b. about 0.01 to about 2 mole parts ZrO 2 ,
c. about 1 to about 6 mole parts BaCO 3 ,
d. about 0.05 to about 0.5 mole parts MnCO 3 ,
e. about 0.01 to about 0.4 mole parts MoO 3 ,
f. about 0.05 to about 2.5 mole parts MgO,
g. about 0.5 to about 7 mole parts Y 2 O 3 , and
h. about 0.3 to about 4 mole parts SiO 2 .
2. The composition of claim 1 comprising a blend of:
a. BaTiO 3 , and the following, per 100 mole parts of BaTiO 3 :
b. about 0.1 to about 1.75 mole parts ZrO 2 ,
c. about 2.5 to about 4.5 mole parts BaCO 3 ,
d. about 0.1 to about 0.4 mole parts MnCO 3 ,
e. about 0.02 to about 0.3 mole parts MoO 3 ,
f. about 0.5 to about 2 mole parts MgO,
g. about 1 to about 6 mole parts Y 2 O 3 ,
h. about 1 to about 3 mole parts SiO 2 .
3. A powder composition for use in forming a dielectric material for use in a multilayer ceramic chip capacitor comprising a blend of:
a. BaTiO 3 , and the following, per 100 mole parts of BaTiO 3 :
b. about 1.5 to about 6 mole parts BaCO 3 ,
c. about 0.1 to about 0.5 mole parts MnCO 3 ,
d. about 0.5 to about 2 mole parts MgO,
e. about 0.5 to about 2.5 mole parts of Lu 2 O 3 ,
f. about 0.25 to about 3.5 mole parts Y 2 O 3 , and
g. about 1 to about 4 mole parts SiO 2 .
4. The composition of claim 3 further comprising, per 100 mole parts BaTiO 3 ,
about 0.5 to about 3.5 mole parts ZrO 2 .
5. A powder composition for use in forming a dielectric material for use in a multilayer ceramic chip capacitor comprising a blend of:
a. BaTiO 3 , and the following, per 100 mole parts of BaTiO 3 :
b. about 1.5 to about 6 mole parts BaCO 3 ,
c. about 0.1 to about 0.5 mole parts MnCO 3 ,
d. about 0.5 to about 2 mole parts MgO,
e. about 0.25 to about 3.5 mole parts Y 2 O 3 ,
f. about 1 to about 4 mole parts SiO 2 , and
g. about 0.5 to about 3.5 mole parts ZrO 2 .
6. The composition of claim 3 , further comprising about 0.02 to about 0.3 mole parts MoO 3 .
7. The composition of claim 3 , further comprising about 0.5 to about 3.5 mole parts CaCO 3 .
8. The composition of claim 3 , further comprising about 0.5 to about 2.5 mole parts of Yb 2 O 3 .
9. The composition of claim 3 , further comprising about 0.01 to 0.5 mole parts MoO 3 .
10. The composition of claim 3 , further comprising about 2 to about 4 mole parts WO 3 .
11. The composition of claim 5 , further comprising about 0.01 to about 0.5 mole parts CaCO 3 .
12. The composition of claim 5 , further comprising about 0.5 to about 2.5 mole parts Lu 2 O 3 .
13. The composition of claim 5 , further comprising about 0.5 to about 2 mole parts Yb 2 O 3 .
14. The composition of claim 5 , further comprising about 0.5 to about 2.5 mole parts MoO 3 .
15. The composition of claim 5 , further comprising about 0.01 to 0.5 mole parts WO 3 .