Title :
Comprehensive electromigration studies on dual-damascene Cu interconnects with ALD WCxNy barriers
Author :
Bruynseraede, C. ; Fischer, A.H. ; Ungar, F. ; Schumacher, J. ; Sutcliffe, V. ; Michelon, J. ; Maex, K.
Author_Institution :
IMEC, Leuven, Belgium
Abstract :
Am important improvement in electromigration (EM) resistance was revealed upon the introduction of atomic-layer-deposited WCN barriers in dual-damascene Cu interconnects. At stress level EM failure were found to increase with WCN thickness and to be consistently superior compared to I-PVD deposited barriers. Although the voiding scenario is identical for both ALD and I-PVD barriers, a reduction of the current density exponent and the activation energy is observed for ALD. In contrast to the influence of WCN barrier thickness on the EM behaviour, the effect of specific pre-clean procedures prior to the ALD process turned out to the less pronounced.
Keywords :
atomic layer epitaxial growth; copper; current density; diffusion barriers; electromigration; integrated circuit interconnections; tungsten compounds; voids (solid); Cu; I-PVD deposited barriers; WCN; WCN barrier thickness; activation energy; atomic-layer-deposited WCN barriers; current density; dual-damascene Cu interconnects; electromigration resistance; electromigration studies; pre-clean procedures; stress level EM failure; voiding scenario; Atomic layer deposition; Copper; Current density; Electromigration; Instruments; Optical wavelength conversion; Stress; Temperature; Testing; Thickness control;
Conference_Titel :
Interconnect Technology Conference, 2004. Proceedings of the IEEE 2004 International
Print_ISBN :
0-7803-8308-7
DOI :
10.1109/IITC.2004.1345666
