Figure 3.

a) AFM topographical image of edge-first writing on PMMA using an applied force F = 300 nN and a line pitch d = 100 nm. The bottom image shows the height profiles of ridge patterns. b) AFM topographical images and height profile of edge scratches (F = 300 nN, d = 40, and 50 nm) on the PMMA surface. c) AFM images of controlled ridge patterns written with d varied between 40 nm on the left to 100 nm on the right, the scale bar is 120 nm. The ridge width measured in each image is shown in the figure below where a transition from an isolated to a proximity regime is evident.