Electrodeposition of insulating poly(phenylene oxide) films with variable thickness

Ability to control key characteristics of electrodeposited polymers plays a vital role for their applications. In this work the results on tailoring the thickness of electronically insulating poly(phenylene oxide) (PPO) type polymer films have been showed. Pinhole-free PPO films with variable thickness in the range of 10–50 nm were grown by controlling the potential applied during the electrochemical polymerization on the surface of titanium nitride (TiN) substrates. The insulating properties of the PPO film were confirmed by testing its permeability to redox species by cyclic voltammetry. Thermal stability of the PPO films with different thicknesses was investigated by in-situ spectroscopic ellipsometry up to 400 °C in various environments. This insight is important for the optimization of the PPO anneal conditions in order to remove the residual solvent and potentially improve the polymer chains stacking. Our results provide the basis for electrodeposition of PPO films with variable thickness for diverse applications.status: publishe