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. 16, 2003
Filed:
Jan. 18, 2000
Applicant:
Inventors:
Assignee:
Matsushita Electronics Corporation, Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 2/1302 ;
U.S. Cl.
CPC ...
H01L 2/1302 ;
Abstract
An etchant for etching at least one of a titanium material and silicon oxide includes a mixed liquid of HCl, NH F and H O. When the etchant has a NH F/HCl molar ratio of less than one, only the titanium material is etched. When the etchant has a NH F/HCl molar ratio of more than one, only silicon oxide is etched. When the etchant has a NH F/HCl molar ratio of one, the titanium material and silicon oxide are etched at the same rate.