Effect of surfactant on preparation of poly(4-vinylphenol)/titanium dioxide composite for a gate insulator of organic thin film transistors

摘要

Composite materials of poly(4-vinylphenol) (PVP) and titanium dioxide (TiO2) nanoparticles were fabricated via a spin coating process in order to enhance dielectric properties for a gate insulator application of the OTFT in this study. In order to improve dispersion stability of the TiO2 nanoparticles in the polymeric solution during the process, a surfactant was also adopted onto the solution mixture. The dispersion property was observed by measuring sedimentation time of TiO2 particles in the polymeric solution, and the effect of surfactant on the surface morphology of the dielectric layer was further analyzed by using atomic force microscopy. Dielectric properties of the PVP-TiO2 composite and performance of OTFTs with the PVP-TiO2 composite insulator are presented, along with their effects on device performance with pentacene layer as a semiconductor.