Sol-gel-derived hybrid conductive films for electromagnetic interference (EMI) shielding

Abstract

The conductive nano-sized zinc particles were embedded in an insulating amorphous silica matrix, and the hybrid films were obtained by a sol-gel method. The stable hybrid sol solution was prepared by hydrolysis and condensation of Methyltrimethoxysilane (MTMS) with a one-step acidic catalyst process. Hybrid films were dip-coated on silicon wafer and cured at 120 °C for 60 minutes. The structural characterization of hybrid films were investigated by means of attenuated total reflection infrared (ATR-IR) spectroscopy and X-ray diffraction (XRD). The electrical properties of the films were examined with four-point probe. Hybrid films showed to be relatively dense, uniform and defect free. The conductivity of hybrid films was varied with the different contents of zinc nanoparticles and the thickness of the film. It was observed that there was the percolation threshold for the film’s electrical properties.

Keywords

sol-gel / hybrid films / conductive / EMI shielding

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