Electromigration in electroplated Cu(Ag) alloy thin films investigated by means of single damascene Blech structures

• Published in: Microelectronic engineering Vol. 86; no. 12; pp. 2396 - 2403
• Main Authors: Strehle, S., Menzel, S., Jahn, A., Merkel, U., Bartha, J.W., Wetzig, K.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.12.2009; Elsevier
• Subjects: Applied sciences; Atomic structure; Blech structures; Condensed matter: structure, mechanical and thermal properties; CONNECTORS (ELECTRICAL); Copper; Copper–silver alloys; Design. Technologies. Operation analysis. Testing; Diffusion in solids; Drift; Electromigration; Electromigration drift experiments; Electronics; ELECTROPLATING; Errors; Exact sciences and technology; INLAYS; Integrated circuits; LINERS; Microelectronic fabrication (materials and surfaces technology); Microelectronics; MOLECULAR STRUCTURE; Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Single damascene technology; THIN FILMS; Transport properties of condensed matter (nonelectronic); Copper–silver alloys; Blech structures; Electromigration drift experiments; Single damascene technology; Copper-silver alloys; Microelectronics; Failures; Damascene process; Interconnections; Integrated circuits; Thin films; Microelectronic fabrication; Tantalum; Alloying effects; Copper alloys; Electrodiffusion; Chemical mechanical polishing; Silver alloys
• ISSN: 0167-9317; 1873-5568
• DOI: 10.1016/j.mee.2009.04.028

Electromigration failure of copper interconnects in microelectronics evokes a need for materials with improved resistance against electromigration effects. Copper–silver alloy thin films are a promising material for the next generation of interconnects and were investigated with respect to their electromigration resistance. The investigations were done by atom drift experiments by means of Blech structures fabricated in single damascene technology with two different Ta-based liner systems. Electromigration induced atom drift could be demonstrated. The resistance against electromigration of Cu(Ag) films appears to be slightly higher than for pure Cu films. However, significant experimental errors are still present. Additionally, de-alloying effects were observed.