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:
Jan. 18, 2000
Filed:
Oct. 30, 1997
Applicant:
Inventors:
Lawrence D David, Enfield, NH (US);
Lisa A Fanti, Hopewell Junction, NY (US);
Assignee:
International Business Machines Corporation, Armonk, NY (US);
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
252 792 ; 438614 ; 438654 ; 438695 ; 438756 ; 216 13 ; 216 72 ; 216108 ;
Abstract
A process and etchant solution for chemical wet etching of thin film metals in the presence of a protected metal. The etching solution has a pH range of about 2.7 to 4.0. The etching solution may include hydrogen peroxide, potassium sulfate, and potassium EDTA, and it reduces or eliminates the incidence of etch-resistant metal without damaging the protected metal.