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:
Dec. 14, 1982
Filed:
Aug. 20, 1980
Fujitsu Limited, Kawasaki, JP;
Abstract
A tantalum film capacitor has an .alpha.-tantalum as a lower electrode, a chemical conversion layer of .alpha.-tantalum as a dielectric and an upper electrode, an improvement involving forming a highly nitrogen-doped tantalum film between the .alpha.-tantalum and a substrate, and also, another improvement involving forming a transitional thin tantalum layer between said highly nitrogen-doped tantalum film and said .alpha.-tantalum. The nitrogen concentration of the highly nitrogen-doped tantalum film is from 14 to 30 atomic %. The electrical properties, especially leakage current, are improved over those of the prior art. A disadvantage of the conventional .alpha.-tantalum thin film capacitor, that is the necessity of using an expensive partial glazed Al.sub.2 O.sub.3 substrate, is eliminated, and a non-glazed Al.sub.2 O.sub.3 substrate can be used in the present invention.