High dielectric constant very low fired X7R ceramic capacitor, and powder for making

A method of manufacturing a dielectric ceramic start powder, comprising the steps of:

• a. intensively wet milling from 0.2 to 2.5 weight percent of barium lithium borosilicate flux, from 0.05 to 0.3 weight percent of MnCO3, from about 0.01 to 0.25 weight percent Co3O4, a grain growth inhibitor selected from the group consisting of niobium compounds Nb2O5, BaNb2O6, CaNb2O6, MgNb2O6, LiNbO3, and mixtures thereof such that a weight percent of Nb2O5 ranges from 0.4 wt % to 1.50 wt %, and tantalum compounds, and mixtures thereof, such that a weight percent of Ta2O5 ranges from 0.66 wt % to 2.50 wt %, and a mixture of molar equivalents of the niobium and tantalum compounds;
• and, from 0.4 to 1.2 weight percent of an additive selected from the group consisting of a rare earth oxide, yttrium oxide, a combination of rare earth oxides, and a combination of yttrium oxide and rare earth oxides, such that ions of the rare earth oxide, ions of the yttrium oxide, ions of the combination of rare earth oxides, and ions of the combination of rare earth oxides and yttrium oxide have an average ionic radius of about 0.97, to achieve a particle size below 1.0 micron;
• b. drying the wet milled compounds at about 150° C.;
• then,
• c. granulating and mildly calcining the dried, wet milled compounds at about 500° C. to 600° C.;
• and,
• d. then mixing the calcined, dried, wet milled compounds with at least ninety weight percent essentially pure barium titanate powder having an average particle size of from 0.2 to 1.2 microns.

A multilayer ceramic capacitor that satisfies X7R performance characteristics having at least one electrode buried within a body of the capacitor, and an external terminal connected to at least one electrode, the body comprising:

• a. at least ninety weight percent essentially pure barium titanate powder having an average particle size of from 0.2 to 1.2 microns;
• b. from 0.2 to 2.5 weight percent of barium lithium borosilicate flux;
• c. from 0.05 to 0.3 weight percent of MnCO3;
• d. a grain growth inhibitor selected from the group consisting of niobium compounds Nb2O5, BaNb2O6, CaNb2O6, MgNb2O6, LiNbO3, and mixtures thereof such that a weight percent of Nb2O5 ranges from 0.4 wt % to 1.50 wt %, and tantalum compounds, and mixtures thereof, such that a weight percent of Ta2O5 ranges from 0.66 wt % to 2.50 wt %, and a mixture of molar equivalents of the niobium and tantalum compounds;
• and,
• e. from 0.4 to 1.2 weight percent of an additive selected from the group consisting of a rare earth oxide, yttrium oxide, a combination of rare earth oxides, and a combination of yttrium oxide and rare earth oxides, such that ions of the rare earth oxide, ions of the yttrium oxide, ions of the combination of rare earth oxides, and ions of the combination of rare earth oxides and yttrium oxide have an average ionic radius of about 0.97 angstroms.