Spin-cast thin films of polyaniline

Abstract

Thin films of polyaniline have been spin cast from solutions of formic acid in concentrations of up to 3 wt.% which give thicknesses between 80 and 250 nm. These films have been patterned using positive photoresist and etched in an oxygen plasma. Silicon wafers with 200 nm of dry thermal oxide and 100 nm of sputtered silicon nitride were used as substrates. Platinum leads in a four-probe configuration were built on top of the insulators and the polyaniline was spun on top of these. Different adhesion promoters were examined for electrical interference. The spin-cast films are sufficiently electroactive to allow for the growth of polyaniline on top of them by electrochemical means.