Patent 7842398 was granted and assigned to NGK Insulators on November, 2010 by the United States Patent and Trademark Office.
The dielectric device includes a substrate, a lower electrode, a dielectric layer, and an upper electrode. The lower electrode is bonded onto the substrate. The dielectric layer is bonded onto the lower electrode. The dielectric layer is obtained through thermal treatment of a film layer formed by spraying of a powdery dielectric material and a fine-particulate metal. In the thus-formed film layer, the metal is dispersed in the matrix of the dielectric material. Thermal treatment of the film layer causes migration of the metal in the film layer. This metal migration causes a lower-electrode-adjacent portion and upper-surface-adjacent portion of the dielectric layer to have different metal contents.