Electrical conduction mechanism in plasma polymerized 1-Benzyl-2-methylimidazole thin films under static electric field

The electrical properties of alternating current plasma polymerized 1-Benzyl-2-methylimidazole (PPBMI) thin films were investigated to determine the dominant carrier transport mechanism under static electric field. Fourier transform infrared (FTIR) spectroscopy was employed for structural analysis of the monomer and that of the PPBMI. The FTIR analyses demonstrate that the chemical structure of PPBMI thin films is changed to some extent from that of the monomer. Current density–voltage characteristics were studied over the temperature range from 300 to 423 K for PPBMI thin films of thicknesses 100, 150, 200 and 250 nm in Al/PPBMI/Al sandwich configuration. It is revealed that the dominant conduction mechanism in PPBMI thin films is space charge limited conduction. The activation energy for the conduction mechanism is found to be 0.43 eV. Carrier mobility, free carrier density and trap density are found to be 1.48 × 10 − 18 to 6.35 × 10 − 18 m 2 V − 1 s − 1 , 1.59 × 10 23 to 5.85 × 10 23 m − 3 and 2.50 × 10 24 to 5.00 × 10 23 m − 3 , respectively.