Title :
Engineering gap fill, microstructure and film composition of electroplated copper for on-chip metallization
Author :
Dubin, V.M. ; Thomas, C.D. ; Baxter, N. ; Block, C. ; Chikarmane, V. ; McGregor, P. ; Jentz, D. ; Hong, K. ; Hearne, S. ; Zhi, C. ; Zierath, D. ; Miner, B. ; Kuhn, M. ; Budrevich, A. ; Simka, H. ; Shankar, S.
Author_Institution :
Portland Technol. Dev., Intel Corp., Hillsboro, OR, USA
Abstract :
Electroplated Cu is being used by the major semiconductor manufacturers as an interconnect material, because it offers a lower line resistance and better electromigration performance over conventional Al metallization. This paper describes the mechanism of "super-fill" as well as gap fill, microstructure, and film composition of electroplated copper. A combination of optimized Cu plating additive chemistry and current waveform enable complete gap fill of 0.07-0.1 μm features (AR>10:1) as well as strong [111] texture, large grains (>3 μm) with a large fraction of twin grain boundaries and controlled impurity content in electroplated Cu films. Electroplating process stability was maintained through the on-line analysis (p/t<0.3) of organic and inorganic bath ingredients and their replenishment.
Keywords :
copper; electroplated coatings; electroplating; impurities; integrated circuit metallisation; surface texture; surface topography; twin boundaries; AFM; Auger depth profiling; Cu; SEM; SIMS; TEM; XRD; controlled impurity content; electroplated copper; engineering gap fill; film composition; inorganic bath ingredients; ion channelling; large grains; microstructure; on-chip metallization; on-line analysis; optimised current waveform; optimised plating additive chemistry; organic bath ingredients; process stability; strong texture; super-fill; surface roughness; twin grain boundaries; voltammetry; Additives; Chemistry; Copper; Electromigration; Inorganic materials; Metallization; Microstructure; Semiconductor device manufacture; Semiconductor films; Semiconductor materials;
Conference_Titel :
Interconnect Technology Conference, 2001. Proceedings of the IEEE 2001 International
Conference_Location :
Burlingame, CA, USA
Print_ISBN :
0-7803-6678-6
DOI :
10.1109/IITC.2001.930081
