Patent ID: 8623770

Claim:
A method for sidewall spacer line doubling on a substrate comprising: providing a substrate; depositing on the substrate a hardmask layer; depositing on the hardmask layer a mandrel layer; patterning the mandrel layer into a plurality of stripes on the hardmask layer, the mandrel stripes having tops and sidewalls; depositing, by thermal atomic layer deposition without plasma assistance and without ozone assistance, a titanium oxide spacer layer on the tops and sidewalls of the mandrel stripes and on the hardmask layer between the mandrel stripes; etching away the spacer layer on the tops of the mandrel stripes and on the hardmask layer between the mandrel stripes, leaving the mandrel stripes and sidewall spacers; etching away the mandrel stripes, leaving stripes of sidewall spacers on the hardmask layer; etching away the hardmask, using the stripes of sidewall spacers as an etch mask; and removing the stripes of sidewall spacers, leaving stripes of hardmask layer on the substrate.