| 초록 |
The polymer bilayer thin film such as polyvinylpyridine(PVP) layer on top of polystyrene(PS) one on a Si substrate undergoes layer inversion due to both a strong affinity of the PVP for the silicon wafer and a preferential wetting of the PS at air/polymer interface during heating above the glass transition temperatures of the two polymers. Capillary lithography of PS(bottom layer) and PVP(top layer) bilayer spin coated on a Si substrate and subsequent proper heat treatments allowed us to control layer inversion. Variation of bilayer thickness induced by capillary lithography lead to controlled microstructures where bottom layer inversion from PS to PVP occurred in thinner areas while the bilayer remained in thicker regions. We have investigated the effect of size of micropatterns, bilayer thickness, temperature and pressure on micropattern formation and layer inversion morphology. The controlled microstructures are characterized by optical microscopy(OM), atomic force microscopy(AFM) and scanning electron microscopy(SEM). Since the controlled inversion morphology gives rise to a chemically modified patterned surface, it is very useful for selective deposition of submicron sized colloidal particles. |
