Spatial and Orientation Control of Cylindrical Nanostructures in ABA Triblock Copolymer Thin Films by Raster Solvent Vapor Annealing

• DOI: 10.1021/nn303416p
• Publication Date: 2012-10-04T17:36:07Z
• Authors: Jonathan E. Seppala; Ronald L. Lewis; Thomas H. Epps
• Keywords: Raster scan

We present a spatially resolved approach for the solvent vapor annealing (SVA) of block copolymer thin films that permits facile and relatively rapid manipulation nanoscale ordering nanostructure orientation. In our method, localized (point) SVA zone is created through use delivery nozzle. This point can be rastered across film using motorized stage to control local structure orientation in cylinder-forming ABA triblock film. At moderate rastering speeds (∼100 μm/s) (i.e., modest time at given point), displayed ordered cylindrical nanostructures with cylinders oriented parallel substrate surface. As speed was decreased (∼10 μm/s), morphology transformed into surface indicative perpendicular These cylinder orientations also were by multiple times over same region, this effect found when either retrace (overlapping) or crossed-path (orthogonal) geometries. Similar trends obtained from various nozzle diameters accounting differences flux time, illustrating universality approach. Finally, we note "stylus-based" raster technique allows annealed approximately 2 orders magnitude faster than conventional "bell jar" annealing.