Method of anisotropically etching adjacent lines with multi-color selectivity

Embodiments provide anisotropic etch processes for silicon carbon nitride (SiCN) or other materials within multi-color structures with improved selectivity to materials in adjacent lines. Cyclic surface modification and activation processes are used to achieve an anisotropic etch with desired selectivity with respect to other materials in a multi-color structure. For example embodiments, selectivity of a first material, such as SiCN or silicon nitride, with respect to other materials in adjacent lines for the multi-color structure is achieved using the cyclic modification/activation processes. The materials within the multi-color structure can include, for example, silicon, silicon nitride, silicon carbon oxide, silicon oxide, titanium nitride, and/or other materials. For one embodiment, hydrogen is introduced to process chemistry to facilitate the surface modification. For one embodiment, a non-corrosive gas, such as nitrogen trifluoride, is included in the process chemistry with the hydrogen.