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:
Oct. 04, 2005
Filed:
Mar. 30, 2004
Amit P. Marathe, Milpitas, CA (US);
Connie Pin-chin Wang, Menlo Park, CA (US);
Christy Mei-chu Woo, Cupertino, CA (US);
Amit P. Marathe, Milpitas, CA (US);
Connie Pin-Chin Wang, Menlo Park, CA (US);
Christy Mei-Chu Woo, Cupertino, CA (US);
Advanced Micro Devices, Inc., Sunnyvale, CA (US);
Abstract
A composite α-Ta/ graded tantalum nitride /TaN barrier layer is formed in Cu interconnects with a structure designed for improved wafer-to-wafer uniformity, electromigration resistance and reliability, reduced contact resistance, and increased process margin. Embodiments include a dual damascene structure in a low-k interlayer dielectric comprising Cu and a composite barrier layer comprising an initial layer of TaN on the low-k material, a graded layer of tantalum nitride on the initial TaN layer and a continuous α-Ta layer on the graded tantalum nitride layer. Embodiments include forming the initial TaN layer at a thickness sufficient to ensure deposition of α-Ta, e.g., as at a thickness of bout 50 Å to about 100 Å. Embodiments include composite barrier layers having a thickness ratio of α-Ta and graded tantalum nitride: initial TaN of about 2.5:1 to about 3.5:1 for improved electromigration resistance and wafer-to-wafer uniformity.