| 摘要 |
Single spacer processes for multiplying pitch by a factor greater than two are provided. In one embodiment, n, where n≧2, tiers of stacked mandrels are formed over a substrate, each of the n tiers comprising a plurality of mandrels substantially parallel to one another. Mandrels at tier n are over and parallel to mandrels at tier n−1, and the distance between adjoining mandrels at tier n is greater than the distance between adjoining mandrels at tier n−1. Spacers are simultaneously formed on sidewalls of the mandrels. Exposed portions of the mandrels are etched away and a pattern of lines defined by the spacers is transferred to the substrate. |
