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. 27, 2001
Filed:
Apr. 17, 1998
Joseph D. Cuchiaro, Colorado Springs, CO (US);
Akira Furuya, Tokyo, JP;
Carlos A. Paz de Araujo, Colorado Springs, CO (US);
Yoichi Miyasaka, Tokyo, JP;
Other;
Abstract
In a ferroelectric integrated circuit, a hydrogen barrier layer comprising titanium or titanium nitride or both is formed over a metal oxide element to protect it from hydrogen degradation. After hydrogen annealing and other process steps causing hydrogenating or reducing conditions, the hydrogen barrier layer is removed in a two-step etching process. The first etch step is a dry etch, preferably a standard ion-mill etching process, which rapidly removes most of the hydrogen barrier layer. The second step is a wet, chemical etch, preferably using a solution containing NH,OH, H,O,, and H,O, which selectively removes remnants of the hydrogen barrier layer from the circuit by oxidizing a chemical element of the barrier layer. The metal oxide material preferably comprises a layered superlattice compound.