RF plasma polymerization and electrical, optical and structural properties of thin films of poly(o-toluidine)

Abstract

Thin films of poly(o-toluidine) (POT) have been prepared by RF plasma polymerization at radio frequency (RF) power input 15 W, making suitable modifications in a RF-sputtering set-up. The deposition rate is found to be 3.33 nm/min. The films are characterized by dc conductivity, UV-Visible, FTIR and XRD techniques. The dc conductivity of the POT thin films has been analyzed in the temperature range 312-435 K and is found to increase with temperature. The Arrhenious plot of dc conductivity shows straight line behaviour. The optical band gap has been estimated to be 1.66 eV from UV-visible absorption spectrum. From FTIR, the formation of POT has been confirmed. It is found that the synthesized polymer is cross-linked. Thickness of the polymer films has been measured to be 200 nm by ellipsometry. XRD shows the amorphous nature of the prepared films.