Understanding the dielectric and electrical transport behaviors of plasma polymerized diethanolamine thin films under alternating electric field

Abstract

A capacitively coupled parallel plate glow discharge reactor has been utilized to develop plasma polymerized diethanolamine (PPDEOA) thin films to look into the alternating current (AC) features of PPDEOA thin films. It is observed that the dielectric constant, epsilon' in PPDEOA thin films enhances by declining the frequency and that increases with increasing temperature. The AC electrical conductivity, sigma(ac) is frequency dependent. The frequency exponent, s values are found to be 0.32 to 1.0 and 1.0 to 1.8 in the lower (10(2)-10(3) Hz) and higher ( > 10(3) Hz) frequencies, respectively. These suggest the presence of hopping conduction in the lower frequency region and other mechanisms in the higher frequency region. The activation energies are derived to be 0.03 to 0.28 eV illustrating the less effect of temperature on them. The real part, M' and imaginary part, M '' of electric modulus vary with frequency. The frequency dependent loss tangent, tan delta is obtained. The epsilon', sigma(ac), and tan delta deviate by the virtue of film thicknesses.