Carbon nitride thin films formed by low energy ion beam deposition with positive and negative ions

Carbon nitride became an attractive system for the search of new functional materials since the existence of crystalline carbon nitride was predicted in 1989. Up to now the research in this field is focused mainly on the realization of the hexagonal phase of C3N4, whose properties have been proposed to be of low-compressibility, having a high thermal conductivity, a high optical band gap and insulating character. Ion beam deposition with mass analyzed positive and negative ions is a new technique for depositing thin films under well characterized conditions, With the Positive And Negative ion Deposition Apparatus (PANDA) the simultaneous deposition of low energy carbon and nitrogen ions under ultrahigh vacuum conditions is possible. Depositions were performed on silicon wafers under change of ion species and transport ratios. Rutherford backscattering was used as well as infrared and Raman spectroscopy in order to get compositional and structural information of the deposited thin films. The results are presented together with an overview of carbon nitride solids reported in the literature.