Interim oxidation of silsesquioxane dielectric for dual damascene process

摘要

Resist developers can attack some advanced dielectric materials such as silsesquioxane materials which can be used as an insulator between a surface of an integrated circuit chip and wiring layers formed on the surface of the dielectric material. By performing a resist stripping or etching process in which a reactant material is supplied externally or liberated from the dielectric material, an extremely thin surface protective covering of an intermediate material may be formed which is impervious to resist developers or any of a plurality of other materials which may damage the flowable oxide material. A dual Damascene process for forming robust connections and vias to the chip can thus be made compatible with advanced dielectrics having particularly low dielectric constants to minimize conductor capacitance and support fast signal propagation and noise immunity even where conductors are closely spaced to each other.