A new approach for the growth of copper nitrides thin films by thermal evaporation using nitrogen as source gas

Thin films of copper nitride (Cu 3 N) were successfully synthesized by thermal evaporation method. The Cu powder was evaporated on glass substrate ina horizontal glass tube furnace having central temperature 1000 °C under a vacuum of 10 −2 m Torr for 25 mints. After evaporation of Cu powder, the temperature of tube furnace was set as 300 °C and nitrogen gas was flown into a tube furnace at a rate of 100 sccm for different time durations of 2–8 h respectively. XRD data demonstrated that only one XRD peak (53.916°) of Cu 3 N phase was observed for sample prepared using nitrogen gas flow time duration 2 h. But as we increased the time duration for nitrogen flow, three diffraction peaks at 2theta 23.005°, 32.9° and 38.228° were observed, which are related due to the (100), (111) and (200) planes of Copper Nitride. The intensity of Cu 3 N related diffraction peaks was found to be increased with increasing the time duration which suggested that good crystal quality was observed in the sample having the time duration of 8 h. We argued that for large time durations of nitrogen gas flow, the surface diffusion of the adatom is increased causes the nitrogen atoms react with free Cu atoms to form Cu 3 N thin films. Raman spectroscopy data demonstrated peaks of Cu 3 N structure at 487 and 608 cm −1 for samples prepared using 6 and 8 h time duration. SEM data further confirmed our XRD and Raman data that sample prepared using 8 h time duration has best crystal quality. The XPS and FTIR measurements were also performed on 8 h annealed sample to further justified the presence of Cu 3 N structure.