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. 06, 2022
Filed:
Apr. 02, 2018
Kanto Denka Kogyo Co.,ltd., Tokyo, JP;
Korehito Kato, Shibukawa, JP;
Yoshihiko Iketani, Shibukawa, JP;
Yukinobu Shibusawa, Shibukawa, JP;
Hisashi Shimizu, Shibukawa, JP;
KANTO DENKA KOGYO CO., LTD., Tokyo, JP;
Abstract
A dry etching gas composition is used which contains a saturated or unsaturated hydrofluorocarbon compound (excluding 1,2,2,3-pentafluorocyclobutane and 1,1,2,2-tetrafluorocyclobutane) represented by a general formula (1):CxHyFz(where x, y, and z are integers that satisfy 2≤x≤4, y+z≤2x+2, and 0.5<z/y<2). Use of the etching gas composition containing the above-described hydrofluorocarbon makes it possible to selectively etch a nitrogen-containing silicon-based film (b1) with respect to a silicon oxide film, a non-silicon-based mask material, or a polycrystalline silicon film.