| 초록 |
The crystal modifications of ultra-thin P(VDF/HFP) film spin-cast on gold substrate are highly dependent on the types of solvent. Five kinds of solvents (acetone, DMF(N,N-dimethylformamide), DMA(N,N-dimethylaceamide), acetone/DMF (4/6) mixture, and acetone/DMA(3/7)) were used in this study. The crystal modification, chain orientation, and dipole orientation of ultra-thin P(VDF/HFP) films were characterized using infra-red grazing incident reflection absorption spectroscopy (GIRAS). Mixture of β- and γ-crystals was observed for all the spin-cast samples. Acetone produced the greatest amount of β-crystal, whereas DMA yielded the least γ-content and the highest β-content. When the ultra-thin film spin-cast on the gold substrate using acetone as a solvent is corona-poled, changes in β- and γ-crystal contents, CF-dipole orientation, and chain orientation were also evaluated using GIRAS and discussed in details. |
