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. 08, 2009
Filed:
Jan. 29, 2007
Nobuyuki Negishi, Tokyo, JP;
Masatoshi Oyama, Kudamatsu, JP;
Masahiro Sumiya, Hikari, JP;
Hitachi High-Technologies Corporation, Tokyo, JP;
Abstract
It is an object to provide a high-precision method for forming deep holes of elliptic pattern, which can improve hole directionality on the short diameter side, the hole directionality being possibly deteriorated as a result of excessive polymer deposition in the initial etching stage. The insulating film dry etching method is for treating a work on which a mask of elliptic pattern is formed with a fluorocarbon gas, wherein the etching process is divided into a first and second steps after the etching is started, the first step operating to deposit a polymer at a rate set lower than that in the second step, and controlling step time in accordance with ellipticity (long diameter/short diameter ratio) of the elliptic pattern.