| 초록 |
We report a new method to control both the nucleation and the growth of SiO2 to form nanopatterns using a tenet biomineralization in nature. Preparing inorganic materials with 3-dimensional and nano-size periodic patterns is the essential steps in designing miniature devices.1 A simple micron-size periodic pattern can be prepared using conventional photolithography.2 On the other hand, complex materials with periodic patterns having sizes below 0.1㎛ cannot be simply constructed using conventional photolithography. Recently, an alternative approach to attain complex nanostructures has been developed by using microphase separated block copolymer as a template.3 The block copolymer can self-assemble to produce periodic nanodomains, such as lamellar, hexagonal, and spherical phases.4 These self-assembled structures with length scales of 10 - 100 nm are ideally suited to control the nucleation, growth, and morphology of inorganic materials,5 and are used for nanoscale patterning.3 To do this, regioselective nucleation is regulated by the difference in interfacial energy between the reaction medium and different nanodomains of the block copolymer.5 Usually, heterogeneous nucleation is favored for the nanodomains which have a lower interfacial energy. Although these methods were successful for two-dimensional nanopatterning, we found that the influence of the morphology of the block copolymer on the nanostructures becomes weaker as the structures build up, so that the boundaries between the patterns become blurred gradually as the thickness increases. To overcome this problem, we have developed a new method to promote the nucleation and growth of SiO2 regioselectively. |
