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:
Jul. 01, 2003
Filed:
Oct. 16, 2001
Ming-Yi Lee, Fremont, CA (US);
LSI Logic Corporation, Milpitas, CA (US);
Abstract
A method for blocking formation of a reacted metal layer on a structure in an integrated circuit. The integrated circuit has a source region, a drain region, a gate, an isolation area formed of a material, and a protective layer formed of substantially the same material as the isolation area. The protective layer overlies at least the source region and the drain region. The method is accomplished while reducing an amount of the material of the isolation area that is removed when the material of the protective layer is removed. A blocking layer is deposited on the integrated circuit. The blocking layer is formed of a material that is substantially different from the material of the isolation area and the protective layer. The blocking layer is patterned to selectively cover portions of the blocking layers that overlie at least the structure and selectively expose portions of the blocking layer that overlie at least the source region, the drain region, and the gate. The exposed portions of the blocking layer are etched with an etchant to substantially remove the exposed portions of the blocking layer, and to expose portions of the protective layer. The etchant etches the blocking layer at a substantially greater rate than the protective layer. The exposed portions of the protective layer are etched for a period of time that is just sufficient to remove the exposed portions of the protective layer, but not sufficient to substantially remove any of the material of the isolation area. Portions of the integrated circuit are thereby exposed, including at least the source region, the drain region, and the gate. Metal is deposited on the exposed portions of the integrated circuit. The metal is reacted with at least the source region, the drain region, and the gate to form the reacted metal layer, and unreacted metal is removed from other exposed portions of the integrated circuit and the blocking layer.