Patent ID: 7914755

Claim:
A method of forming a composition-modified barium titanate ceramic powder, with a formula of (Ba 1-α-μ-ν A μ D ν Ca α )[Ti 1-x-δ-μ′-ν′ Mn δ A′ μ′ D′ ν′ Zr x ] z O 3 , where A=Ag or La, A′=Dy, Er, Ho, Y, Yb, or Ga; D=Nd, Pr, Sm, or Gd; D′=Nb or Mo, 0.10≦x≦0.25; 0≦μ≦0.01, 0≦μ′≦0.01, 0≦ν≦0.01, 0≦ν′≦0.01, 0≦δ≦0.01, 0.995≦z≦1, and 0≦α≦0.005 the method comprising: individually forming each of a plurality of water-stable constituent ion chelates, wherein each of the water-stable constituent ion chelates is formed from a constituent ionic species of the ceramic powder, ammonium hydroxide, and a chelate agent, a plurality of water-stable constituent ion chelates including ionic species zirconium, manganese, yttrium, lanthanum, and neodymium, the chelate agent comprising 2-hydroxypropanoic acid or an alpha-hydroxycarboxylic acid selected from the group consisting of 2-hydroxyethanoic acid, 2-hydroxybutanedioic acid, 2,3-dihydroxybutanedioic acid, 2-hydroxy-1,2,3-propanetricarboxylic acid, 2-hydroxybutanoic acid, 2-hydroxypentanoic acid, and 2-hydroxyhexanoic acid; providing a plurality of precursor materials in an aqueous solution, a first precursor material of the plurality of precursor materials comprising Ba(NO 3 ) 2 and calcium nitrate, a second precursor comprising a stable titanium alpha-carboxylic acid chelate, a third precursor material of the plurality of precursor materials comprising the plurality of water-stable constituent ion chelates; combining the plurality of precursor materials in the aqueous solution with a precipitant solution to cause coprecipitation of primary particles of the ceramic powder in a combined solution, the precipitant solution comprising tetraalkylammonium hydroxide, the primary particles comprising the first, second, and third precursors; refluxing the coprecipitated primary particles of the ceramic powder; separating the ceramic powder from the combined solution; and calcining the ceramic powder, the primary particles of the ceramic powder comprising composition-modified barium titanate having a perovskite structure.