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:
Apr. 13, 2010
Filed:
Sep. 12, 2006
Yoshitaka Nakamura, Tokyo, JP;
Keiji Kuroki, Tokyo, JP;
Yoshitaka Nakamura, Tokyo, JP;
Keiji Kuroki, Tokyo, JP;
Elpida Memory, Inc., Tokyo, JP;
Abstract
A semiconductor storage device is manufactured by the following steps. A cylindrical hole is formed in an interlayer insulating film. Then, a multilayer conductive layer including a first sublayer and a second sublayer is formed over the entire surface of the insulating interlayer including the internal surface of the hole. The second sublayer has a higher nitrogen content than the first sublayer. A cup-like lower electrode is formed by reactive ion etching of the conductive layer under conditions that the second sublayer is etched faster than the first sublayer, so that the conductive layer remains only on the internal surface of the hole, and so that the upper edge of the remaining conductive layer forms an angle of 45° or less with the internal wall of the hole. Then, a capacitor insulating layer and an upper electrode are formed in that order on the lower electrode.