Si-related color centers in nanocrystalline diamond thin films

The successful growth of nanocrystalline diamond (NCD) thin films with optically active Si-related color centers was realized on glass and molybdenum substrates by the microwave plasma chemical vapor deposition (CVD) with focused or linear antenna plasma reactors. Diamond coatings were characterized by Raman spectroscopy, scanning electron microscopy, and photoluminescence (PL) spectroscopy. Increased of a-Si interlayer thickness resulted in reduction of stress in NCD film and increased renucleation of NCD films. The PL spectra showed that the Si-color center is only observed in the focused plasma system. The influence of the substrate material as well as the a-Si interlayer on the density of Si-related color center was not confirmed in our setup.