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:
Mar. 28, 2000
Filed:
Jun. 26, 1997
Galeb H Maher, North Adams, MA (US);
Veerabhadrarao Bheemineni, Latham, NY (US);
MRA Laboratories, North Adams, MA (US);
Abstract
Multilayer capacitors with have been made including a cadmium silicate flux by firing in a closed crucible at about 1100.degree. C. to provide a high K and smooth X7R coefficient of K with temperature, but tend to acquire a low insulation resistance in a high temperature life test under voltage. This problem was solved heretofore by the added step of a post-sinter anneal. However, the anneal step adds cost and further complexity to the manufacturing process. Through a number of experiments it has been discovered that by the addition of a very small and critical quantity of a calcium compound such as calcium carbonate or calcium niobate to the start ceramic powder that the unwanted anneal step may be eliminated while maintaining a high insulation resistance in an accelerated life test and with only a very small reduction of dielectric constant or smoothness with temperature