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. 30, 1999
Filed:
Feb. 21, 1997
Kazuhide Abe, Kawasaki, JP;
Shuichi Komatsu, Yokohama, JP;
Mitsuaki Izuha, Chiba, JP;
Noburu Fukushima, Tokyo, JP;
Kenya Sano, Kawasaki, JP;
Takashi Kawakubo, Yokohama, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A thin film capacitor including a first electrode having on its surface a (100) face of cubic system or a (001) face of tetragonal system, a dielectric thin film epitaxially grown on the first electrode and exhibiting a crystal structure which inherently belongs to a perovskite structure of cubic system, and a second electrode formed on the dielectric thin film. Further, the dielectric thin film meets the following relationship V/V.sub.0 .gtoreq.1.01 where a unit lattice volume of true perovskite crystal structure belonging to the cubic system (lattice constant a.sub.0) is represented by V.sub.0 =a.sub.0.sup.3, and a unit lattice volume (lattice constant a=b.noteq.c) which is strained toward a tetragonal system after the epitaxial growth is represented by V=a.sup.2 c, and also meets the following relationship c/a.gtoreq.1.01 where c/a represents a ratio between a lattice constant 'c' in the direction thicknesswise of the film and a lattice constant 'a' in the direction parallel with a plane of the film.