Patent ID: 6087287
Filing Date: 2000-07-11
Classification: H01G

Abstract:
A process for the manufacture of a dielectric ceramic which comprises(a) providing a mixture of a major proportion of ABO.sub.3, where A is selected from among Ba, Ba+Ca, and Ba+Ca+Sr, where B is selected from among Ti, Ti+Zr, Ti+R, and Ti+Zr+R, R being one or more rare earth metals selected from among Sc, Y, Gd, Dy, Ho, Er, Yb, Tb, Tm, and Lm, and where O is oxygen, and a minor proportion of Mg;(b) molding the mixture into a shape, and(c) firing the shape to form a ceramic having a multiplicity of crystal grains each having a paraelectric shell enclosing a ferroelectric core, the shells of the crystal grains having a depth ranging from about five percent to about 30 percent of the average size of the crystal grains.