Low-temperature synthesis and physical characteristics of PS TiO2 hybrid films for transparent dielectric gate applications

We report the low-temperature (100 °C) processing and characteristics of PS TiO2 cross-linked hybrid films, obtained by a simple sol-gel route using titanium butoxide (TB) as the inorganic source, styrene (ST) as the organic source, and 3-trimetoxy-silyl-propyl- methacrylate (TMSPM) as the coupling agent. The films were characterized by FTIR to identify the characteristic chemical groups. TGA determined the content of the organic and inorganic components. AFM and SEM images revealed the homogeneous and smooth surface with very low roughness of the hybrid films. At macroscopic level, the hybrid films were homogeneous with high transparency and high refractive index, determined from optical spectroscopy. These characteristics support the formation of a cross-linked hybrid material with strong bonds between organic and inorganic phases. The hybrid films dielectric characteristics were studied by measuring capacitance-voltage (C V) and current-voltage (I V) curves in metal-insulator-metal (MIM) structures. The dielectric constant measured was 5.2 and leakage current around 10−6 A/cm2.