  Self-assembly of soft materials attracts keen interest for patterning
applications owing to its ease and spontaneous behavior. We report the
fabrication of nanogrooves using sublimation and recondensation of liquid
crystal (LC) materials. First, well-aligned smectic LC structures are obtained
on the micron-scale topographic patterns of the microchannel; then the
sublimation and recondensation process directly produces nanogrooves having
sub-200-nm scale. The entire process can be completed in less than 30 min.
After it is replicated using an ultraviolet-curable polymer, our platform can
be used as an alignment layer to control other guest LC materials.
