Figure 5: Complex bidirectional customization.
From: Enabling complex nanoscale pattern customization using directed self-assembly
(a–c and e–h) SEM images of the prepattern and resulting DSA patterns. (b) and (c) are overlaid with their corresponding false colour-orientation maps. (a) HSQ prepattern incorporating a masking feature outlining the letters ‘IBM’. (b) DSA pattern after PMMA removal for H≈1 L0 after 5 min. thermal annealing at 265 °C. Inset: zoomed-in view of the area with ‘IBM’. (c) DSA pattern after PMMA removal for H≈1.6 L0 after 5 min. thermal annealing at 265 °C. Inset: zoomed-in view of the area with ‘IBM’. (d) Plot of the fraction of the ‘IBM’s featuring defects local to the IBM region for the DSA patterns at H≈0.8, 1.0, 1.2 and 1.6 L0 against the corresponding thermal annealing time period. (e) Zoomed-in view of the area with ‘IBM’ in (a). (f) DSA pattern after PMMA removal for H≈1.2 L0 after 5min. thermal annealing at 265°C over the ‘IBM’ logo based on the prepatterns in (a). (g) Facsimile of the IBM logo in a grating generated through DSA at H≈1.2 L0 based on the prepattern in (a). (h) Tone-inverted IBM logo generated through DSA. Scale bars are 1 μm (a–c) and 100 nm (e–h).
