Phases and physical properties of carbon nitride thin films prepared by pulsed laser deposition

Pulsed laser deposition combined with atomic beam techniques have been exploited to grow carbon nitride thin films with controlled nitrogen composition. The nitrogen composition in the thin films was found to increase as the laser fluence was decreased for laser ablation at both 532 and 248 nm wavelengths. Analysis of these carbon nitride materials shows that over a wide range of conditions the film growth rate determines the overall nitrogen composition, although at the lowest growth rates the composition saturates at a value close to 50% nitrogen. Infrared spectroscopy indicates that a cyanogen-like impurity is present in all of the films with nitrogen composition greater than 30%, and that the amount of this impurity increases with increasing nitrogen content. However, the cyanogen-like impurity phase was eliminated by a thermal annealing process to yield a single phase material. Systematic studies of the carbon nitride film electrical resistivity and thermal conductivity as a function of nitrogen composition will be discussed.