Masking Process and Structures Formed Thereby

A method comprising:

• forming an inverse mask over a dielectric layer, the inverse mask comprising strips;
• forming a mask layer conformally over the strips;
• removing horizontal portions of the mask layer;
• forming vertical portions of the mask layer adjoining respective sidewalls of the strips to have partially-rounded upper surfaces, the partially-rounded upper surfaces being rounded away from the respective sidewalls of the strips;
• removing the strips;
• forming the vertical portions of the mask layer to have fully-rounded upper surfaces throughout respective lateral widths of the vertical portions, the vertical portions of the mask layer with fully rounded upper surfaces forming a mask;
• and
• forming recesses in the dielectric layer using the mask.

A method comprising:

• forming a titanium nitride inverse mask comprising strips over a dielectric layer;
• conformally depositing an oxygen-containing titanium mask layer over the strips;
• etching the mask layer to remove horizontal portions of the mask layer and to at least partially round surfaces of vertical portions of the mask layer, the vertical portions being adjacent respective sidewalls of the strips, the surfaces being at least partially rounded in a direction away from the respective sidewalls;
• thereafter, simultaneously etching the vertical portions of the mask layer and the strips of the inverse mask to remove the strips and to fully round upper surfaces distal from the dielectric layer, the etching the strips of the inverse mask being at a greater rate than the etching the vertical portions of the mask layer, the fully round upper surfaces being throughout respective widths of the vertical portions;
• and
• forming recesses in the dielectric layer using the vertical portions of the mask layer with the fully round upper surfaces as a mask.