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:
Apr. 01, 2008
Filed:
Mar. 28, 2006
Applicant:
Masahiro Ogasawara, Nirasaki, JP;
Inventor:
Masahiro Ogasawara, Nirasaki, JP;
Assignee:
Tokyo Electron Limited, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
H01L 21/302 (2006.01);
U.S. Cl.
CPC ...
Abstract
In a first step and a thirst step, etching gases are used which contain fluorocarbon gases having C/F atom number ratios higher than that in a second step. A hole is formed to a midpoint in a silicon oxide film in the first step, the hole is formed until a base SiN film begins to be exposed or immediately before it is exposed in the second step, and overetching is performed in the third step. This enables even a hole having a fine diameter and a high aspect ratio to be formed in an excellent shape.