Characterization of low dielectric constant polyaniline thin film synthesized by ac plasma polymerization technique

Abstract

Polyaniline thin films were prepared by ac plasma polymerization technique. Capacitance, dielectric loss, dielectric constant and ac conductivity of these films were investigated in the frequency range from 100 Hz to 1 MHz and in the temperature range from 300 to 373 K. Capacitance and dielectric loss decreased with frequency and increased with temperature. This type of behaviour was found to be in good agreement with an existing model. The ac conductivity σ (ω) was found to vary as ω s with the index s 1. Annealing of polyaniline thin films in high vacuum at 373 K for 1 h was found to reduce the dielectric loss. FTIR studies reveal that the aromatic ring is retained in the polyaniline thin films, which enhances the thermal stability of the polymer films.

Lowkthin films based on rf plasma-polymerized aniline

“…At present, low k materials used in IC technology are based on silicon and they are employed in the form of SiO 2 as ILD/IMD [1,3,4]. Hence, the search for alternative low k materials is in progress and the onus of replacing the SiO 2 -based ILD/IMD is on polymer-based materials [1,5]. Some of the potential candidate materials to be used as ILD/IMD are polyimides, polyindan, poly(aryl ether)s, poly(silsesquioxane)s and poly(benzoxazole)s [1].…”

Transparent Conducting Polymer/Nitride Semiconductor Heterojunction Solar Cells

“…Conductivity in TCPs is generated by a polaron in the -conjugated bond; this polarized state causes a Debye-type dielectric dispersion response against an applied alternating electric field (Cole et al, 1941). Referring to a previous study on the frequency-dependent capacitance of PANI film (Mathai et al, 2002), the characteristics can be analyzed by assuming an equivalent circuit consisting of a frequency-independent capacitive element, C 0 , in parallel with a resistive element, R, both in series with a constant low-value resistance. Based on this model, the frequencydependent capacitance of TCP, C p , is given by the following equation:…”

The thickness dependence of dielectric properties in the plasma polymer thin films

“…Where C is the capacitance of the sample, d is the thickness of the sample, ε 0 is the permittivity [3,29,30] When the frequency dependent dielectric constant for the thin film with thickness of 20 nm was investigated, it was observed that there were two relaxation mechanisms. One of these mechanisms was observed at frequencies lower than 100 Hz and the other mechanism was observed at frequencies higher than 100 Hz.…”

“…[12,13,21,22]. In addition, there are reports on the dielectric properties of [2,23,24] and on the comparison of their dielectric properties with the structural properties of plasma polymers [25][26][27][28][29]. However, there are no reports on of the pPEO dependent on the film thicknesses.…”