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. 23, 1999
Filed:
May. 27, 1997
Thomas K Dougherty, Playa Del Rey, CA (US);
O Glenn Ramer, Los Angeles, CA (US);
Raytheon Company, El Segundo, CA (US);
Abstract
Oxide materials having a composition described by the formula SrBi.sub.2.00- Ta.sub.2.00-x Nb.sub.x O.sub.9, where x ranges from 0.00 to 2.00 and is controlled to within about 1%, are provided having improved high temperature performance. A batch of the desired composition is initially prepared by conventional processes to provide a nominal composition that may be close to the desired composition, but not the exact desired composition. A portion of the batch is processed to form a thin film, the stoichiometry of which is then analyzed. The batch composition is then modified by adding thereto a quantity of one or more of the constituents to bring the batch composition to the desired stoichiometry. Further improved high temperature performance is achieved with values of x within the range of about 0.10 to 1.9, and more preferably, about 0.4 to 0.7, and most preferably about 0.56. The thus-modified metal organic acid salt solutions provide ceramic thin films having improved electrical properties (particularly consistent properties from batch-to-batch, improved ferroelectric remnant polarization, and much improved high temperature performance) as compared to the thin films prepared from unmodified solutions. The present invention provides for new materials, particularly new niobium-substituted, bismuth-layered structured materials and a process to make these materials on a consistent batch-to-batch basis.