Surface nanopatterning by polymer self-assembly: From applied research to industrial applications

Complementary methods have been developed for surface nanostructuring using molecular self-assembly, reactive ion etching and replication techniques. First, controlled surface nanostructures with tunable lateral dimensions from tens of nanometer to tens of micrometers have been produced by polymer self-assembly, over large area and at low cost. The resulting nanostructures could find applications as antireflective layer or as security features for traceability and anti-counterfeiting applications. Second, the as-deposited polymeric surface structures could be used as micro- and nano-patterned etch masks for the transfer of the structure into the underlying material through reactive ion etching. This process leads to more durable structures with tunable aspect ratios from 1:1 to 10:1 in hard materials such as silicon, silicon nitride or quartz. Potential applications of these techniques include the development of superhydrophobic and self-cleaning surfaces for MEMS, as well as the fabrication of nanoporous membranes for ultrafiltration. Polymeric nanopatterns can also be used as mastering tools for replication. Casting, embossing and moulding of self-assembled structures in plastics have all been shown to be possible.