Investigation of the enlargement of Ru grains and failure modes analysis in microsecond UV laser annealing
Résumé
Interconnects based on Ru has been considered as a promising candidate to replace Cu-based interconnects for the future technology nodes thanks to its low bulk resistivity (ρ), its short electron mean free path (e-MFP) and the possibility to have a barrier-less integration. In this work, we demonstrate that μs UV Laser Annealing (UV- LA) is an interesting process strategy to reduce the metal line resistance by enlarging grains in thin Ru films. A method based on numerical simulations has been proposed to optimize the LA conditions to lower the Ru film ρ close to the bulk one, while avoiding the apparition of structural damages such as wrinkles or buckling.