초록 |
We report the directed self-assembly (DSA) of metal nano particles (NPs) on soft line patterns of poly(tetrafluoroethylene) (PTFE). As a bar of PTFE is dragged across a flat Si wafer surface above the melting point of PTFE, topographic line patterns parallel to the dragging direction are produced to the substrate. Then the substrate with the PTFE line patterns is chemically modified with polymer brushes. Afterwards, as metal NPs solution is spin-coated, the NPs are instantly self-assembled between soft PTFE lines. We think that this observation may be due to the synergetic effect of height contrast of soft PTFE lines and surface energy difference imparted by polymer brushes. To investigate the effect of polymer brushes on the DSA of NPs, their chain length and types of monomers are controlled. Finally, by applying RIE process, only uniform arrays of the NPs are remained on the wafer, but all organic components are removed. The DSA of NPs is characterized by using AFM and SEM. |