Fig. 1. Process flowchart of MENSLL (Process A) and NSCL (Process B).

Fig. 2. (a) Simulated structure of FDTD; Electric field distributions for (b) 1200-nm-diameter nanosphere and (c) 600-nm-diameter nanosphere; Electric field distribution in XY plane for tilt exposure with the tilted angle (d) $\alpha =30°$, (e) $\alpha =45°$, (f) $\alpha =60°$. Insets: Electric field distribution in XZ plane.

Fig. 3. Plane-view SEM images for samples after (a) twin exposures when $\alpha =26.6°$ and $\varphi =0°$, 180°, (b) triple exposures when $\alpha =26.6°$ and $\varphi =0°$, 120°, 240°, (c) quadruple exposures when $\alpha =26.6°$ and $\varphi =0°$, 90°, 180°, 270°, (d) quintuple exposures when $\alpha =30°$ and $\varphi =0°$, 90°, 180°, 270°, and $\alpha =0°$ and $\varphi =0°$, (e) twin exposures when $\alpha =45°$ and $\varphi =0°$, 90°, (f) triple exposures when $\alpha =45°$ and $\varphi =0°$, 120°, 240°. The black scale bar is 4 μm.

Fig. 4. SEM images of (a) the nanosphere monolayer after developing, (b) the nanosphere cleared partly, and (c) close-pack nanorings. The black scale bar is 2 μm.

Fig. 5. SEM images of nanring fabricated by shrinking silica spheres for (a) 180, (b) 270, and (c) 360 s. Insets: side view images. The black scale bar is 1 μm.

Fig. 6. SEM images of nanorescents fabricated in the conditions of (a) $\alpha =26.6°$ and shrinking silica spheres for 180 s, (b) $\alpha =45°$ and shrinking silica spheres for 180 s, and (c) $\alpha =26.6°$ and shrinking silica spheres for 270 s. Insets: side view images. The black scale bar is 1 μm.

Fig. 7. SEM images of hierarchical multiple structures with (b) triple exposures when $\alpha =26.6°$ and 0°, 120°, 240°, (c) quadruple exposures when $\alpha =26.6°$ and 0°, 90°, 180°, 270°, (d) quintuple exposures when $\alpha =26.6°$ and $\varphi =0°$, 72°, 144°, 216°, 288°. The black scale bar is 3 μm.