Process for treating porous low k dielectric material in damascene structure to form a non-porous dielectric diffusion barrier on etched via and trench surfaces in the porous low k dielectric material

摘要

A process for forming a non-porous dielectric diffusion barrier layer on etched via and trench sidewall surfaces in a layer of porous low k dielectric material comprises exposing such etched surfaces to a plasma formed from one or more gases such as, for example, O₂; H₂; Ar; He; SiH₄; NH₃; N₂; CH_xF_y, where x1-3 and y4-y; H₂O; and mixtures of same, for a period of time sufficient to form from about 1 nanometer (nm) to about 20 nm of the non-porous dielectric diffusion barrier layer which prevents adsorption of moisture and other process gases into the layer of porous low k dielectric material, and prevents degassing from the porous low k dielectric material during subsequent processing.