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:
Nov. 09, 1999
Filed:
Jul. 25, 1997
Applicant:
Inventor:
Yoshikazu Tsunemine, Hyogo, JP;
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
438240 ; 438-3 ;
Abstract
In a semiconductor memory device and a manufacturing method thereof, a barrier metal layer having a step h.sub.2 which is smaller than the step h.sub.1 at the upper end of a contact hole is formed on the surface opposite to the contact hole. The barrier metal layer has a nitrogen concentration gradient which becomes higher from its lower layer to its upper layer. A semiconductor memory device provided with a highly planer capacitor lower electrode, and a method of manufacturing the semiconductor memory device can thus be provided.