Evidence for continuous areas of crystalline β-C3N4 in sputter-deposited thin films

Carbon nitride films have been deposited using Penning-type opposed target de reactive sputtering. These films show large (>10 mu m(2)) continuous areas of nanocrystalline material in an amorphous matrix. Electron diffraction shows the nanocrystalline areas to have crystallography consistent with the beta-C3N4 phase. Film chemistry analysis using Rutherford backscattering and Raman spectroscopy indicates that only carbon, nitrogen, and trace levels of hydrogen are present. Given this film chemistry and the fit of diffraction data to that predicted for the beta-C3N4 structure, it seems likely that the sputtering parameters used have, indeed, produced continuous regions of the elusive beta-C3N4 phase.