Effect of iodine doping on the electrical transport mechanism in plasma polymerized 2,6-diethylaniline thin films

• Electrical transport mechanism in iodine doped 2,6-diethylaniline thin films.
• The electrical conductivity increased due to iodine doping.
• Poole–Frenkel (PF) conduction is operative rather than Schottky after iodine doping.
• PF conduction may be originated due to the charge transfer complex formation.
• The presence of charge transfer complex is confirmed by a new absorption peak.

The current density–voltage characteristics of pure and iodine doped plasma polymerized 2,6-diethylaniline (PPDEA) thin films of different thicknesses ranging from 150 to 450 nm with aluminum (Al)/PPDEA/Al structure have been investigated at room temperature. The direct current electrical conductivity has showed a higher value due to iodine doping of PPDEA thin film. In contrast to pure PPDEA thin films where the most probable conduction mechanism is electrode limited Schottky type, Poole–Frenkel (PF) conduction mechanism is found to be operative in iodine doped PPDEA thin films. The PF conduction mechanism in iodine doped PPDEA thin films may have generated due to the charge transfer complex formation through donor type monomer and acceptor type iodine. The presence of charge transfer complex is confirmed by a new absorption shoulder/peak in ultraviolet–visible spectrum of iodine doped PPDEA thin film.