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. 21, 2004
Filed:
Feb. 28, 2002
Shuichi Noda, Tokyo, JP;
Oki Electric Industry Co., Ltd., Tokyo, JP;
Abstract
To determine an optimum addition ratio of ethyl alcohol in the etching gas in a plasma etching unit, an ethyl alcohol addition ratio at which the isotropic etching rate of the etching mask is obtained, and on the basis of the obtained ethyl alcohol addition ratio, the optimum addition ratio is determined, by performing an etching process using an etching gas containing ethyl alcohol in the optimum addition ratio, the portions of the bottom antireflective coating which are not covered with the etching mask are removed. Thus, it is possible to provide a novel etching method capable of appropriately removing unnecessary portions of the bottom antireflective coating which are not covered by photoresist without causing much damage to the photoresist used as the etching mask.