Highly photoconductive amorphous carbon nitride films prepared by cyclic nitrogen radical sputtering

We report on the growth of amorphous carbon nitride films sa-CNxd showing the highest conductivity to date. The films were prepared using a layer-by-layer method sa-CNx :LLd, by the cyclical nitrogen radical sputtering of a graphite radical, alternated with a brief hydrogen etch. The photosensitivity S of these films is 105, defined as the ratio of the photoconductivity sp to the dark conductivity sd and is the highest value reported thus far. We believe that the carriers generated by the monochromatic light (photon energy 6.2 eV) in the a-CNx :LL films are primarily electrons, with the photoconductivity shown to increase with substrate deposition temperature. © 2004 American Institute of Physics. [DOI: 10.1063/1.1792384]