Figure 3.

Influence of the dose accumulation effect on pillars sizes. SEM images of periodic pillars arrays realized with a period of 1.5 $\mathsf{\mu }$m (a) and with a period of 0.6 $\mathsf{\mu }$m (b); (c) pillar diameters as a function of the distance between pillars (the period of the array). The laser power and the writing speed were fixed at 36 mW and 4 $\mathsf{\mu }$m/s, respectively, for all pillars; (d) schematic illustration of the dose accumulation effect due to the short distance between two pillars, which creates a nano-connection between pillars.