Analysis of critical dimension uniformity for step and flash imprint lithography

Step and Flash Imprint Lithography (SFIL) is one of several new nano-imprint techniques being actively developed. While SFIL has been shown to be capable of sub-30 nm resolution, critical dimension (CD) control of imprinted features must be demonstrated if SFIL is to become a viable and production worthy lithography technique. In the current study, a Molecular Imprints Imprio-100 system was used to imprint resolution patterns on 200 mm wafers. A characterization of critical dimension uniformity over the all-quartz template was done and compared to the same features printed on wafers. This analysis was performed for 100, 80, 50, and 30 nm features in three ways: over a single die using 64 sites arrayed across a 21 mm field, from field-to-field for 37 die across a single wafer, and from wafer-to-wafer for six wafers. Results show that CD's transfer from template to wafer with a slight positive bias which is greatest for 50 and 30 nm line sizes. Feature profiles printed for this study were more rounded and sloped than in previous studies. Despite this, the maximum calculated component of process variation from the SFIL process itself was calculated to be only 6 nm (3sigma).