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:
Jun. 11, 2002
Filed:
Aug. 19, 1999
Kazumi Sugai, Tokyo, JP;
NEC Corporation, , JP;
Abstract
Disclosed herein is a method for forming an embedded metal wiring comprising the steps of: forming a wiring trench, a barrier metal film and a conductive metal film; exposing the barrier metal film by polishing the conductive metal film by use of a polishing liquid and an oxidizing agent having a first concentration; and forming a wiring by polishing and removing the exposed barrier metal film by use of a polishing liquid and an oxidizing agent having a second concentration lower than the first concentration. The excessive polishing of the conductive metal occurs when an oxidizing agent having a relatively large concentration while such an oxidizing agent is needed when the barrier metal film is polished and removed. In order to attain the smooth removal of the barrier metal film and to prevent the excessive removal of the conductive metal, the oxidizing agent having a lower concentration is employed in the polishing of the conductive metal.