Low - k Polyimide/Silica Nanocomposites for Microelectronics Applications

The temperature and frequency dependence of dielectric permittivity of hybrid polyimide/silica nanocomposites, prepared by the in situ generation of crosslinked organosilicon nanophase by sol-gel techniques, was investigated by broadband dielectric relaxation spectroscopy. Dielectric permittivity decreases and its frequency and temperature dependence becomes weaker in the hybrids as compared to pure polyimide. The results are explained in terms of loose inner structure of the spatial aggregates of the organosilicon nanophase and reduced polymer dynamics in the hybrids. Water sorption measurements from the vapor phase show reduced water contents of the nanocomposites with respect to pure polyimide. These results suggest that the hybrids under investigation may have a reasonably good potential as low-k materials for microelectronics applications