An interconnect structure is provided that includes at least one patterned and cured photo-patternable low k material located on a surface of a patterned and cured oxygen-doped SiC antireflective coating (ARC). A conductively filled region is located within the at least one patterned and cured photo-patternable low k material and the patterned and cured oxygen-doped SiC ARC. The oxygen-doped SiC ARC, which is a thin layer (i.e., less than 400 angstroms), does not produce standing waves that may degrade the diffusion barrier and the electrically conductive feature that are embedded within the patterned and cured photo-patternable low k dielectric material and, as such, structural integrity is maintained. Furthermore, since a thin oxygen-doped SiC ARC is employed, the plasma etch process time used to open the material stack of the ARC/dielectric cap can be reduced, thus reducing potential plasma damage to the patterned and cured photo-patternable low k material. Also, the oxygen-doped SiC ARC can withstand current BEOL processing conditions.