Figure 3
Surface properties of narrow-patterned PDMS used as an alignment layer.
The pattern width was 50 μm. AFM images of narrow-patterned PDMS films fabricated at IB powers of (a) 600 eV, (b) 1200 eV and (c, d and e) 2400 eV. (c) The left side of the PDMS irradiated with the IB and the right side of the PDMS not irradiated with the IB in one sample denoted as region A are shown. (d) A region 15 μm away from the edge of the IB-irradiated site. (e) Centre region between IB-irradiated sites, where an LC is aligned. (f, g, h and i) Schematic depiction of the mechanism for the formation of narrow-patterned PDMS films through IB treatment. (f and g) Top side of narrow-patterned PDMS. The red lines indicate the directions of expansion of the PDMS caused by the heat of the IB irradiation. The blue lines indicate the directions of cooling-induced contraction of the PDMS. (g and i) Lateral side of narrow-patterned PDMS. (j) 3D image corresponding to (c). (k) 3D image corresponding to (b). (l and m) Cross-line profiles of patterned PDMS treated with IB irradiation at 2400 eV and 1200 eV, respectively.
