Electroless deposition of CoWP: Material characterization and process optimization on 300 mm wafers

International audienceThe use of copper as a metal for interconnections has driven the apparition of new technological solutions. Selective barriers against copper diffusion deposited by electroless reaction bring interests in term of electromigration. In this article, CoWP electroless barriers deposited in a 300 mm Semitool Raider equipment are studied. Good uniformity for a standard thickness of 15 nm is demonstrated. Different growth rates of the barrier as a function of copper grain orientation are observed. The composition of the barrier is constant throughout the film. The deposition is selective, but corrosion phenomena and a superficial metallic contamination on the interline dielectric are revealed. The selectivity of the process is confirmed electrically for 12 nm thick barriers. The impact of copper corrosion on line resistance is addressed through preclean optimization

Alpha-Lipoic Acid Supplementation Restores Early Age-Related Sensory and Endothelial Dysfunction in the Skin

Many changes characterize skin aging, and the resulting dysfunctions still constitute a real challenge for our society. The aim of this study was to compare the skin aging of two rat strains, Wistar and Brown Norway (BN), considered as “poorly aging” and “healthy aging” models, respectively, and to assess the effect of alpha-lipoic acid (LPA), especially on skin microcirculation. To this purpose, various skin characteristics were studied at 6, 12, and 24 months and compared to the results of LPA treatment performed at 12 or 24 months. Skin aging occurred in both strains, but we showed an early occurrence of different age-related disorders in the Wistar strain compared to BN strain, especially regarding weight gain, glycemia dysregulation, basal skin perfusion, endothelial function, and skin resistance to low pressure. LPA treatment tended to improve skin resistance to low pressure in BN but not in Wistar despite the improvement of basal skin perfusion, endothelial function, and skin sensory sensitivity. Overall, this study confirmed the healthier aging of BN compared to Wistar strain and the positive effect of LPA on both general state and skin microcirculation

Electroless deposition of Co-based barriers: selectivity, corrosion and growth properties.

International audienceElcctroless metallic caps are convincing alternatives to standard SiC(N) barriers for the 45 nm technology node and beyond to improve electromigration resistance and limit the dielectric constant of the structures. In this work, particular emphasis is put on possible selectivity issues, corrosion of the copper lines and nucleation/growth properties for two processes (Pd-activated Co\VP and Pd-free CoWB) deprniited in an industrial 300 mm equipment Co\VP process exhibits promising results for 12 nm nominal thickness. For both processes, the control of the preclean step seems to be fundamental to limit copper corrosion. Under optimal conditions, line resistance increase is limited to less than 3 %