Conductive Transparent TiNx/TiO2 Hybrid Films Deposited on Plastics in Air Using Atmospheric Plasma Processing

The successful deposition of conductive transparent TiNx/TiO2 hybrid films on both polycarbonate and silicon substrates from a titanium ethoxide precursor is demonstrated in air using atmospheric plasma processing equipped with a high-temperature precursor delivery system. The hybrid film chemical composition, deposition rates, optical and electrical properties along with the adhesion energy to the polycarbonate substrate are investigated as a function of plasma power and plasma gas composition. The film is a hybrid of amorphous and crystalline rutile titanium oxide phases and amorphous titanium nitride that depend on the processing conditions. The visible transmittance increases from 71% to 83% with decreasing plasma power and increasing nitrogen content of the plasma gas. The film resistivity is in the range of approximate to 8.5x101 to 2.4x105 ohm cm. The adhesion energy to the polycarbonate substrate varies from approximate to 1.2 to 8.5 J/m2 with increasing plasma power and decreasing plasma gas nitrogen content. Finally, annealing the film or introducing hydrogen to the primary plasma gas significantly affects the composition and decreases thin-film resistivity.