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:
Aug. 26, 1997
Filed:
Mar. 27, 1995
Hirohisa Usuami, Higashimurayama, JP;
Kazuyuki Tsunokuni, Koganei, JP;
Masayuki Kojima, Kokubunji, JP;
Kazuo Nojiri, Higashimurayama, JP;
Keiji Okamoto, Kodaira, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi ULSI Engineering Corporation, Tokyo, JP;
Abstract
A process for forming an upper-layer fin and a lower-layer fin of a storage electrode, and a semiconductor integrated circuit device fabricated by the process. When two-layered polycrystalline silicon films are to be sequentially etched to form the upper-layer fin and the lower-layer fin by the dry-etching method using a first mask, the upper polycrystalline silicon film is patterned at first so far as to form the clearance of the upper-layer fins with the minimum working size of the memory cells of a DRAM, to form the upper-layer fin. Next, the lower-layer fin is formed by the dry-etching method using a second mask which has a pattern enlarged in self-alignment from the pattern of the first mask, so that it is given a larger horizontal size than that of the upper-layer fin.