Mask formation processing

A method comprising:

• providing sacrificial spacing structures disposed over a substrate structure, the sacrificial spacing structures comprising a sacrificial material and a protective hard mask material, the protective hard mask material being disposed over the sacrificial material of the sacrificial spacing structures;
• disposing a sidewall spacer layer conformally over the sacrificial spacing structures;
• selectively removing the sidewall spacer layer from above the sacrificial spacing structures to expose the protective hard mask material thereof, the selectively removing comprising leaving, at least in part, sidewall spacers along sidewalls of the sacrificial spacing structures;
• providing a protective material layer over the substrate structure;
• and
• removing the exposed protective hard mask material from the sacrificial spacing structures, the protective material layer protecting the substrate structure during the removing of the exposed protective hard mask material from the sacrificial spacing structures, and thereafter, removing the sacrificial material of sacrificial spacing structures, as well as the protective material layer, leaving the sidewall spacers over the substrate structure as a mask.