Surface melting model for Al reflow into submicron contact-holes and vias

A new simulation model for Al reflow into submicron contact-holes and vias is developed for the first time. This model, the surface melting model, introduces surface tension driven mass transport of Al in a surface reflow layer whose thickness depends on the reflow temperature. Using this model in a quasi-3D computational fluid dynamics code, evolution of 3D Al surface topography during the reflow is accurately predicted from the initial Al step coverage and window curvature for a contact-hole. This physically based simulation identifies nature of the Al reflow.<>