Function through structure: An atomistic view on the additive action at copper/electrolyte interfaces

Superfill (bottom-up) phenomena relevant for Damascene processing typically rely on the time-dependent interplay of various organic and inorganic additives with both the metallic copper surface and with cuprous ions as intermediates of the copper electro-reduction in the near-surface regime. In-situ STM, in-situ SXRD (Surface X-Ray Diffraction) measurements combined with DFT calculations provide new insights into the competitive additive-additive and additive-substrate interactions under non-reactive and reactive conditions. These results are discussed in the light of successful fill experiments of sub-50 nm Damascene features.