Patent ID: 8921034

Claim:
A method of patterning a base, comprising: forming first masking features over a first region of the base, and forming second masking features over a second region of the base; the first and second masking features comprising pedestals of carbon-containing material capped with silicon oxynitride; forming a protective mask over the second masking features while leaving the first masking features exposed; removing the silicon oxynitride caps from the first masking features while the protective mask remains over the second masking features; forming spacers along sidewalls of the first masking features; removing the protective mask and the carbon-containing material of the first masking features while leaving the second masking features remaining over the second region and while leaving the spacers remaining over the first region; and transferring patterns of the spacers and second masking features into one or more materials of the base to pattern said one or more materials.