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. 31, 2000
Filed:
Mar. 18, 1999
Vikram Pavate, San Jose, CA (US);
Seshadri Ramaswami, Saratoga, CA (US);
Murali Abburi, Santa Clara, CA (US);
Murali Narasimhan, San Jose, CA (US);
Applied Materials, Inc., Santa Clara, CA (US);
Abstract
A copper sputtering target is provided for producing copper films having reduced in-film defect densities. In addition to reducing dielectric inclusion content of the copper target material, the hardness of the copper target is maintained within a range greater than 45 Rockwell. Within this range defect generation from arc-induced mechanical failure is reduced. Preferably hardness is achieved by limiting grain size to less than 50 microns, and most preferably to less than 25 microns. The surface roughness preferably is limited to less than 20 micro inches, or more preferably, less than 5 micro inches to reduce defect generation from field-enhanced emission. This grain size range preferably is achieved by limiting the purity level of the copper target material to a level less than 99.9999%, preferably within a range between 99.995% to 99.9999%, while reducing particular impurity levels.