| US 7,468,320 B2 | ||
| Reduced electromigration and stressed induced migration of copper wires by surface coating | ||
| Chao-Kun Hu, Somers, N.Y. (US); Robert Rosenberg, Cortlandt Manor, N.Y. (US); Judith M. Rubino, Ossining, N.Y. (US); Carlos J. Sambucetti, Croton-on-Hudson, N.Y. (US); and Anthony K. Stamper, Williston, Vt. (US) | ||
| Assigned to International Business Machines Corporation, Armonk, N.Y. (US) | ||
| Filed on Jul. 19, 2005, as Appl. No. 11/183,773. | ||
| Application 10/054605 is a division of application No. 09/361573, filed on Jul. 27, 1999, granted, now 6,342,733. | ||
| Application 11/183773 is a continuation of application No. 10/054605, filed on Nov. 13, 2001, abandoned. | ||
| Prior Publication US 2005/0266673 A1, Dec. 01, 2005 | ||
| Int. Cl. H01L 21/44 (2006.01) | ||
| U.S. Cl. 438—656 [438/687; 438/678; 438/660; 438/626; 438/652; 257/E23.154] | 9 Claims |
| 1. A method for forming conductors with high electromigration resistance comprising
forming a layer of dielectric on a substrate,
forming at least one trench in said layer of dielectric,
forming a metal liner in said trench,
forming a conductor selected from the group consisting of copper and copper alloys on said metal liner filling said trench,
forming a planarized upper surface of said conductor planar with the upper surface of said layer of dielectric,
forming a conductive film over said upper surface of said conductor, said conductive film forming a metal to metal metallurgical
bond to provide high electromigration resistance and high resistance to thermal stress voiding,
annealing said substrate in one of an inert or reducing atmosphere at a temperature of at least 300° C. for at least 2 hours
whereby excellent adhesion is obtained between said conductor and said conductive film,
and wherein said conductive film has a thickness of 1 to 20 nanometers and is at least one member selected from the group
consisting of CoWP, CoSnP, CoP, CoB, CoSnB, CoWB, NiB, Pd, In, and W.
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