By incorporating an etch control material after the formation of a material layer to be patterned, an appropriate material having a highly distinctive radiation wavelength may be used for generating a distinctive endpoint detection signal during an etch process. Advantageously, the material may be incorporated by ion implantation which provides reduced non-uniformity compared to etch non-uniformities, while the implantation process provides the potential for introducing even very “exotic” implantation species. In some embodiments, the substrate-to-substrate uniformity of the patterning of dual damascene structures may be increased.