Laminated ceramic capacitor and manufacturing method therefor
AssigneeMurata Manufacturing Co., Ltd.
InventorsHitoshi Nishimura, Masahiro Naito, Tomotaka Hirata, Shinya Isota
Life of this patent
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Abstract
A laminated body that contains a perovskite-type compound containing Sr, Ba, Zr, and Ti and containing; Si; Mn; Al; and V. When the total content of Zr and Ti is 100 parts by mol, the total content m of Sr and Ba meets 100≦m≦105, the Si content a meets 0.1≦a≦4.0, the Mn content b meets 0.1≦b≦4.0, the Al content c meets 0.01≦c≦3.0, the V content d meets 0.01≦d≦0.3, the molar ratio w of Sr and Ba to Sr meets 0.60≦w≦0.95, the molar ratio z of the total of Zr and Ti to Zr meets 0.92≦z≦0.98, w and y meets and the crystal grains are 1.2 μm or less in average grain size.
Claims20
A laminated ceramic capacitor comprising:
- a laminated body comprising a plurality of stacked dielectric ceramic layers and a plurality of internal electrodes at interfaces between adjacent dielectric ceramic layers of the plurality of stacked dielectric ceramic layers;
- and
- an external electrode on an outer surface of the laminated body and electrically connected to the plurality of internal electrodes,
- wherein the laminated body contains:
- Si, Mn, Al, V, and a perovskite-type compound containing Sr, Ba, Zr, and Ti,
- when a total content of Zr and Ti is 100 parts by mol:
- (a) a total content m (parts by mol) of Sr and Ba meets 100≦m≦105,
- (b) a Si content a (parts by mol) meets 0.1≦a≦4.0,
- (c) a Mn content b (parts by mol) meets 0.1≦b≦4.0,
- (d) an Al content c (parts by mol) meets 0.01≦c≦3.0,
- (e) a V content d (parts by mol) meets 0.01≦d≦0.3,
- (f) a molar ratio w of a total of Sr and Ba to Sr meets 0.60≦w≦0.95,
- (g) a molar ratio z (Zr/(Zr+Ti)) of a total of Zr and Ti to Zr meets 0.92≦z≦0.98, and
- the plurality of dielectric ceramic layers each have crystal grains, and the crystal grains are 1.2 μm or less in average grain size.
A laminated ceramic capacitor comprising:
- a laminated body comprising a plurality of stacked dielectric ceramic layers and a plurality of internal electrodes at interfaces between adjacent dielectric ceramic layers of the plurality of stacked dielectric ceramic layers;
- and
- an external electrode on an outer surface of the laminated body and electrically connected to the internal electrodes,
- wherein the laminated body contains:
- Si, Mn, Al, V, and a perovskite-type compound containing Sr, Ba, Zr, and Ti,
- when a total content of Zr and Ti is 100 parts by mol after the laminated body is subjected to dissolution treatment and made into a solution:
- (a) a total content m (parts by mol) of Sr and Ba meets 100≦m≦105,
- (b) a Si content a (parts by mol) meets 0.1≦a≦4.0,
- (c) a Mn content b (parts by mol) meets 0.1≦b≦4.0,
- (d) an Al content c (parts by mol) meets 0.01≦c≦3.0,
- (e) a V content d (parts by mol) meets 0.01≦d≦0.3,
- (f) a molar ratio w of a total of Sr and Ba to Sr meets 0.60≦w≦0.95,
- (g) a molar ratio z of a total of Zr and Ti to Zr meets 0.92≦z≦0.98, and
- the plurality of dielectric ceramic layers each have crystal grains, and the crystal grains are 1.2 μm or less in average grain size.
A laminated ceramic capacitor comprising:
- a laminated body comprising a plurality of stacked dielectric ceramic layers and a plurality of internal electrodes at interfaces between adjacent dielectric ceramic layers of the plurality of stacked dielectric ceramic layers;
- and
- an external electrode on an outer surface of the laminated body and electrically connected to the internal electrodes,
- wherein the dielectric ceramic layers contain:
- Si, Mn, Al, V, and a perovskite-type compound containing Sr, Ba, Zr, and Ti,
- when a total content of Zr and Ti is 100 parts by mol:
- (a) a total content m (parts by mol) of Sr and Ba meets 100≦m≦105,
- (b) a Si content a (parts by mol) meets 0.1≦a≦4.0,
- (c) a Mn content b (parts by mol) meets 0.1≦b≦4.0,
- (d) an Al content c (parts by mol) meets 0.01≦c≦3.0,
- (e) a V content d (parts by mol) meets 0.01≦d≦0.3,
- (f) a molar ratio w of a total of Sr and Ba to Sr meets 0.60≦w≦0.95,
- (g) a molar ratio z of a total of Zr and Ti to Zr meets 0.92≦z≦0.98, and
- the plurality of dielectric ceramic layers each have crystal grains, and the crystal grains are 1.2 μm or less in average grain size.
A method for manufacturing a laminated ceramic capacitor, the method comprising:
- (1) preparing a ceramic slurry by mixing a Si compound, a Mn compound, an Al compound, a V compound, and a powder including a perovskite-type compound containing Sr, Ba, Zr, and Ti,
- wherein in the ceramic slurry, when a total content of Zr and Ti is 100 parts by mol:
- a) a total content m (parts by mol) of Sr and Ba meets 100≦m≦105,
- b) a Si content a (parts by mol) meets 0.1≦a≦4.0,
- c) a Mn content b (parts by mol) meets 0.1≦b≦4.0,
- d) an Al content c (parts by mol) meets 0.01≦c≦3.0,
- e) a V content d (parts by mol) meets 0.01≦d≦0.3,
- f) a molar ratio w of a total of Sr and Ba to Sr meets 0.60≦w≦0.95, and
- g) a molar ratio z (Zr/(Zr+Ti)) of the total of Zr and Ti to Zr meets 0.92≦z≦0.98;
- (2) forming the ceramic slurry into a sheet shape to obtain ceramic green sheets;
- (3) stacking the ceramic green sheets and conductor patterns to form an unfired laminated body;
- and
- (4) firing the unfired laminated body to obtain a laminated body that has a structure with internal electrodes provided at interfaces between adjacent dielectric ceramic layers of a plurality of stacked dielectric ceramic layers, and has crystal grains of 1.2 μm or less in average grain size included in the dielectric ceramic layers.
A method for manufacturing a laminated ceramic capacitor, the method comprising:
- (1) preparing a mixture by weighing and mixing a Si compound, a Mn compound, an Al compound, a V compound, and a powder including a perovskite-type compound containing Sr, Ba, Zr, and Ti, and making the mixture into slurry,
- wherein in the mixture, when a total content of Zr and Ti is 100 parts by mol,
- a) a total content m (parts by mol) of Sr and Ba meets 100≦m≦105,
- b) a Si content a (parts by mol) meets 0.1≦a≦4.0,
- c) a Mn content b (parts by mol) meets 0.1≦b≦4.0,
- d) an Al content c (parts by mol) meets 0.01≦c≦3.0,
- e) a V content d (parts by mol) meets 0.01≦d≦0.3,
- f) a molar ratio w of a total of Sr and Ba to Sr meets 0.60≦w≦0.95, and
- g) a molar ratio z (Zr/(Zr+Ti)) of the total of Zr and Ti to Zr meets 0.92≦z≦0.98;
- (2) forming the slurry into a sheet shape to obtain ceramic green sheets;
- (3) stacking the ceramic green sheets and conductor patterns to form an unfired laminated body;
- and
- (4) firing the unfired laminated body to obtain a laminated body that has a structure with internal electrodes provided at interfaces between adjacent dielectric ceramic layers of a plurality of stacked dielectric ceramic layers, and has crystal grains of 1.2 μm or less in average grain size included in the dielectric ceramic layers.
Dependencies are inferred from the claim text.