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:
Sep. 22, 1998
Filed:
Jan. 11, 1996
Applicant:
Inventor:
Masanobu Zenke, Tokyo, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
438255 ; 438398 ; 438964 ;
Abstract
On a semiconductor substrate (1), a polysilicon layer (3) of a random crystal structure is formed. The polysilicon layer (3) is treated by an etchant to provide a roughened surface (3a) of the polysilicon layer (3). The roughened surface (3a) is formed along grains of a random crystal structure and extends over all of top and side surfaces of the polysilicon layer (3). Thus, the polysilicon layer (3) serves as a lower electrode (4) having an increased surface area. A capacitor insulator layer (5) is deposited on the lower electrode (4). An upper electrode (6) is deposited on the capacitor insulator layer (5).