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. 14, 2025
Filed:
Feb. 14, 2022
Hitachi High-tech Corporation, Tokyo, JP;
HITACHI HIGH-TECH CORPORATION, Tokyo, JP;
Abstract
A method for etching a silicon oxide film at a high selection ratio with respect to a silicon nitride film while a high etching rate of the silicon oxide film is balanced with a low etching rate of the silicon nitride film. The etching processing method is a dry etching processing method for etching a film without using plasma by supplying gas into a process chamber, the film having a side wall of a groove or a hole constituted by respective end parts of laminated film layers formed on a wafer, the laminated film layers including silicon oxide films each sandwiched between silicon nitride films, and in which the silicon oxide films are etched laterally from the end parts with the wafer being set to a low temperature equal to or less than (0.040x−42.0° C.) when a partial pressure of hydrogen fluoride gas is taken as x (Pa).