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:
May. 20, 2003
Filed:
Apr. 24, 2002
Subhash Gupta, Singapore, SG;
Simon Chooi, Singapore, SG;
Paul Ho, Singapore, SG;
Mei Sheng Zhou, Singapore, SG;
Chartered Semiconductor Manufacturing Ltd., Singapore, SG;
Abstract
An inexpensive and safe copper removal method in the fabrication of integrated circuits is described. Copper is stripped or removed by a chemical mixture comprising an ammonium salt, an amine, and water. The rate of copper stripping can be controlled by varying the concentration of the ammonium salt component and the amount of water in the mixture. Also a novel chemical mixture for stripping copper and removing copper contamination is provided. The novel chemical mixture for removing or stripping copper comprises an ammonium salt, an amine, and water. For example, the novel chemical mixture may comprise ammonium fluoride, water, and ethylenediamine in a ratio of 1:1:1.