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:
Nov. 05, 2019
Filed:
Mar. 21, 2017
Canon Kabushiki Kaisha, Tokyo, JP;
Atsunori Terasaki, Kawasaki, JP;
CANON KABUSHIKI KAISHA, Tokyo, JP;
Abstract
A method for processing a silicon substrate includes forming a structure having a bottom surface and a depth of 200 μm or more or 300 μm or more from a first surface of a silicon substrate, forming a protective film on an inner wall of the structure, and performing plasma etching so as to selectively remove the protective film disposed on the bottom surface of the structure with respect to the protective film disposed on the substantially perpendicular side wall of the structure, wherein the plasma etching is performed under the condition in which plasma with a sheath length at least 10 times the depth when the depth is 200 μm or more, or at least 5 time the depth when the depth is 300 μm or more, is generated and a mean free path of ions generated in the plasma is longer than the sheath length.