The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 23, 1991
Filed:
Jan. 11, 1990
Galeb H Maher, North Adams, MA (US);
MRA Laboratories, Inc., North Adams, MA (US);
Abstract
Disc and multilayer ceramic capacitors having a fine grained barium titanate body having been sintered at less than 1100.degree. C. exhibit a high dielectric constant and a smooth (X7R) temperature coefficient of capacitance. Such capacitors are made by mixing barium titanate powder of less than 0.6 micron average particle size, with around 2 weight percent of a silicate flux serving as a reactivity and sintering promoter and one weight percent Nb.sub.2 O.sub.5 serving as a reactivity and sintering inhibitor. After preparing a green body of this mixture, the body is sintered at about 1100.degree. C. In the case of making a multilayer monolithic capacitor, the buried electrodes contain no more than 30 weight percent palladium, and adjacent pairs of the buried electrodes have been spaced apart as close as 5 microns in capacitors of this fine grained high dielectric constant X7R ceramic leading to very high packing density.