Treatment of nanocrystalline diamond films by nitrogen implantation using PIII processing

The influence of N 2 Plasma Immersion Ion Implantation (PIII) on undoped nanocrystalline diamond (NCD) films grown on silicon substrate by CVD process using a hot filament reactor was systematically studied. Before and after the implantation, NCD films were investigated using scanning electron microscopy (SEM), high resolution X-ray diffraction (HRXRD) and Raman scattering spectroscopy. Significant changes in the film surface morphologies due to the plasma implantation treatment were observed. The NCD morphology changed from “cauliflower-like” to a smoother surface after the nitrogen-plasma immersion. The Raman spectra are similar for the three kind of electrodes before and after PIII of 15 and 30 min. Although a small difference among the ratios concerning the D and G Raman band intensities ( I D/ I G) may be observed that seems to increase after the plasma treatment, associated to the disorder increase caused by nitrogen incorporation in the sp 2 phase. Electrochemical response also showed that implanted NCD films had their electrical conductivity improved while the electron transfer kinetics decreased for such NCD films after 15 and 30 min of N 2 implantation.