Dielectric, Thermally Stimulated Discharge Current, Pyroelectric and Surface Morphology of Pmma Thin Films Prepared by Isothermal Immersion

Abstract

Metal–Insulator–Metal structure was used to investigate the dielectric, thermally stimulated discharge current(TSDC)and pyroelectric behavior of poly methyl methacrylate(PMMA)thin films prepared by isothermal immersion method. The surface morphology and the structure of the above said films were studied by using atomic force microscopy(AFM)and X-ray diffraction(XRD)respectively. The XRD spectrum of as grown and films annealed at 513 K indicated the amorphous nature. No pits and dendritic features were observed from the AFM spectrum. The only important topographic features observed is the hillocks of about 10–12 nm large with a peak to valley vertical distance of about 0.5–1 nm. Both as grown and films annealed at 513 K showed very smooth surface and amorphous nature. From the TSDC spectrum activation energy(E), capture cross-section(σ), escape frequency(ν)and relaxation time(τ)were calculated. The observed amorphous phase, low loss, dielectric and thermal behavior imply the feasibility of utilizing PMMA thin films as gate dielectric insulator layer in organic thin film transistors(OTFTs), which can find application in flat panel display.