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:
Oct. 05, 1999
Filed:
Jan. 21, 1998
Yoshihiko Okamoto, Tokyo, JP;
Tadashi Yoshida, Hyogo, JP;
Hiroshi Ohnishi, Tokyo, JP;
Kenichi Hanaoka, Tokyo, JP;
Shigeki Nakajima, Tokyo, JP;
Junichi Tsuchimoto, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Ryoden Semiconductor System Engineering Corporation, Hyogo, JP;
Abstract
An amorphous silicon conductive film on a semiconductor wafer is treated with hydrofluoric acid to remove a natural oxide film therefrom, and then a very thin oxide film is formed on the semiconductor wafer. Thereafter, a silane gas is used to form a nucleating film, followed by annealing to cause the surface of the conductive film be roughened. The very thin oxide film is formed in a thickness of 0.5 angstroms to 20 angstroms. The very thin oxide film is alternatively formed either by treatment with an aqueous hydrofluoric acid solution or by flushing treatment. Thus, a roughened surface having a satisfactory roughness is uniformly formed on the surface of a conductive film on a semiconductor wafer.