Papers by Author: Wan Haliza Abd Majid

Abstract: The annealing temperature of 250nm PVDF-TrFE (70:30 mol%) spin coated thin films were optimized. The annealing temperature were varies starting from solvent evaporation (T_s), Curies transition (T_c), up to melting temperature (T_m). The result shows that the dielectric constant increases with the increasing of annealing temperature. Supported with the XRD observation indicating there were an improvement in crystallinity consistently with the increasing of the annealing temperature. Morphological properties of the annealed PVDF-TrFE thin films were observed by utilizing Field Emission Scanning Electron Microscope (FESEM) at 100k magnification. It can be found that, the annealing temperature promotes the development of elongated crystallite structure which known as ferroelectric crystal. However, the presence of nanoscale cracks on the thin film annealed at 160°C (AN160, over T_m) suggesting high possibility to posed defects while in device applications.

Abstract: The molecular organization of the phospholipids Langmuir-Blodgett (LB) films on solid substrates has been studied via Fourier Transform Infra Red (FTIR) spectroscopy. In this study, the formation of well organized ultra thin LB films of phospholipid molecules has been performed by depositing the monolayer onto the solid substrates of silicon wafer. The space filling molecular models of two types of phospholipids have been proposed on the basis of the FTIR spectra.