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:
Jun. 12, 2001
Filed:
Feb. 06, 1998
Applicant:
Inventor:
Naoyuki Yoshida, Tokyo, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 2/976 ; H01L 2/994 ;
U.S. Cl.
CPC ...
H01L 2/976 ; H01L 2/994 ;
Abstract
A semiconductor memory device comprises a bottom electrode of a capacitor connected to a source region of a semiconductor substrate through a contact plug formed in a portion of a through-hole. The remaining portion of the through-hole has a side-wall film, on which a portion of the bottom electrode film is disposed. The two-level structure of the through-hole improves the step coverage of the side-wall film and avoids over-etching of the silicon substrate.